Introduction

Implementing the best available evidence and enabling positive sustainable change in practice is an enviable goal for anyone providing healthcare services. In this final article of a three-part series, we will discuss applying the evidence and methods of evaluating the outcome, as the final two parts of taking an evidence-based approach. These final two parts are arguably the most important but are often perceived as the two most difficult to achieve.

In general dental practice there are any number of barriers to implementing effective change, including the healthcare system, the will of staff, patient expectations and time available. That said, this stage does not need to be overly complex but it does need to be planned and there are a number of tools we can use to deliver evidence-based dentistry to each and every patient. This article is focused on giving some practical advice and pointers.

Systems thinking

Any challenge is easier when it is broken down into smaller chunks. So think of what you are trying to achieve, then the process that takes place to get to that goal and the system it is part of. Everything we interact with is a system, and there are processes within that system. As soon as we walk out the door in the morning we begin to interact with systems and we start processes.

The footpath network is part of a national infrastructure system that we interact with, queuing for a coffee at the train station is part of a small local system, the surgery at work is a complex local system with many interacting and moving parts. Within these systems there are various different processes; for example, the footpath network has a series of pedestrian crossings, the process to crossing the road will often start by pushing a button and waiting for the green man on the traffic lights, but, of course, it is often a lot more complex than this.

In order to understand the system and how best to implement evidence within a system you need to be able to map the processes you are thinking of changing and determine what might influence the application of evidence. This is called process mapping. Once you have the map, then you can think about the possible barriers to applying the best evidence and equally think about what would enable application of best evidence. The ultimate system makes it easy to do the right thing without relying on humans to do so. Equally, an effective system can make it difficult to do the wrong thing.

Figure 1 illustrates how a process map for crossing the road might look. This map is very simple and doesn’t take into account all potential choices or influences, but it should give you an idea of how to go about constructing a process map (see below).

Let’s return to our clinical example of our paediatric patient in practice whose parent has withheld consent for fluoride varnish application. After completing parts 1,2 and 3 of an evidence-based approach, (1: Asking the right question, 2: Searching for the best available evidence, 3: Critically appraising the evidence), and based on the evidence found, we are confident that for this child, fluoride varnish application would be the best approach to prevent decay. The current barrier to you doing so is the lack of consent from the parent. We need a pragmatic solution to the problem, and providing the information only at the time of application at chair side may not be the best solution. There are many different elements of the system and processes that lead up to that point that could influence the outcome. The appointment booking, check-in, walking to the chair, interaction between you the child and the parent. How many members of staff have been parts of the process? Any change will need to take the system, processes and staff into account. Likewise, there have been a number of tools used, including IT, telephones and dental instruments that also need to be taken into account. A good way to visualise the process and possibly facilitate brainstorming sessions with staff is to again create a process map, similar to Figure 2 (below). This figure is quite obviously simplified, as in reality there are many more influences and choices!

So thinking of the system, the processes and the current barrier, how about if a leaflet had gone out with the appointment in advance that explained the benefits of the treatment to the parent, would it have helped? This could be a change idea to test out in the practice. There are a number of ways that you could implement and evaluate this change.

We will look at a few methods at our disposal. First: Quality improvement methodology.

What is quality improvement (QI)?

QI is an approach we can use to build change into processes and systems that is sustained. It is a new kid on the block in dentistry, but it has been around in healthcare for more than 30 years and for much longer in industry.

The first formal introduction to QI in Scottish dentistry was through the Scottish Patient Safety Programme
in 2016.

Our healthcare colleagues working in the acute and other Scottish primary care services have been doing QI for just over 10 years now. We have some catching up to do, but the benefit is that we can learn from those that have gone before. There are plenty of QI success stories published in a bespoke journal for QI, BMJ quality and safety.

QI methodology and science take a pragmatic approach to implementation of change in a system, focused on tests of change and clear measures so we understand the implications of any change. This controlled approach to implementing change is ideal for use in dental practices. QI is also ideal for finding ways to implement best practice that is supported by evidence.

There is a level of skill and knowledge required to maximise all the QI tools available. NES has developed a number of useful resources that can be accessed online to help navigate QI.

Changes to the SDR in October 2017 mean that dentists can now include quality improvement work where
this would have been traditionally audit activity.

Peer review

Another method to achieve the final two parts of an evidence-based approach might be to use peer review. This is a process of collaborative working with colleagues to establish a group that facilitates peer-to-peer discussion. It involves practitioners outside your practice and could bring a fresh point of view to the processes in your practice. NES has laid out some advice on the requirements of a peer review group on their website.

If done correctly this approach can be used to fulfil quality improvement hours.

One way to use peer review to improve care might be for discussion and implementation of the updated SDCEP guidance on paediatric dentistry that has recently been published1.

You could establish a local group of dentists to come together and discuss the guidance, using it as your standard of care and benchmarking against it, then working together to make changes that will benefit patients and improve the quality of care.

In our example of using a leaflet as a test of change, the practice down the road might have more success in winning parents over because they give the leaflet out with appointment letters rather than when they arrive at the reception desk. Or they might have more experience of paediatric dentistry and could share some tips on behavioural management and helping kids accept treatment.

Behaviour change models

Sometimes implementation can come up against a lot of barriers and it seems like there is no path through all the issues and reasons not to change. Susan Michie’s research group at University College London has produced a number of models and theories that could be helpful.

The TRIADS (translational research in a dental setting) team uses some of these methods alongside guidance development and implementation of SDCEP guidance 2. Thinking about barriers to change, it is sometimes down to the physical confines of the working environment or maybe it is the people within it. There are various methods for helping to work through the barriers and understand how to break them down and facilitate positive behaviour change.

The theoretical domains framework is made up of 14 domains that can help you understand what the barriers are by providing a framework to create questions from3.

For example, the first domain is knowledge, questions in this domain might look like: Do practitioners know that new SDCEP guidance for paediatrics has been published? The second domain is skills; a question in this domain might be: Do dentists in the practice know how to place a Hall crown?

Once you gain answers to these questions you can begin the frame ideas and develop facilitators that will enable application of evidence-based practice and guidance. That might be issuing each practitioner with the guidance and arranging a team meeting to discuss it, changing pro-formas on the surgery operating system to include risk assessments that hadn’t been previously included or arranging for the practice to have a training day on fitting Hall crowns. You can only come up with effective solutions if at first, you understand the real underlying barriers. You can read more about the TDF in a free open access journal.

Evaluating the outcome further

All of the approaches above have evaluation built in. The usual go-to mechanism for measuring and evaluating change tends to be a traditional style audit of pre- and post-intervention data collection. This is an effective method of evaluating an outcome, but it only gives a snapshot, usually of quantitative data, of an ongoing and dynamic system. This type of audit activity still has a place to ensure standards are met and identify areas where there could be improvements but we shouldn’t be restricted to it.

There are many other ways of evaluating outcomes and presenting evidence of effective change. It is important though, to distinguish between process measures and outcome measures. In the fluoride varnish example, a process measure might be the number of successful applications of varnish applied, but the outcome measure would be the reduction in caries rate or continued prevention of caries for the patient. Having the ultimate health outcome in mind throughout the project is important, as after all everything the project is striving to achieve is improve the quality of care we provide to patients and improve their health.

Qualitative feedback from staff on a new process is an important measure when evaluating outcomes and could be gathered in staff meetings or in questionnaire form. Staff often come up with pragmatic and innovative ideas that might not have been thought of previously.

Gathering patient feedback is another very valuable measure. The Scottish Government’s Health and Social Care standards provide some useful questions and themes to base outcome markers on 4. An example of the headline outcomes in the document are ‘I have confidence in the people who support and care for me’ and ‘I am fully involved in all decisions about my care and support’. The document is worth a read; the standards are meant to compliment already existing standards set out by various legislative bodies.

Staff and patient feedback could be combined with quantitative data as part of the evaluation of a project in your practice. Returning to QI, the method of quantitative data collection in QI uses a sustained approach to data collection. QI has a programme of active data collection taking place throughout the change process. Instead of collecting large amounts of data at two time points, QI asks that you collect smaller amounts of data at more regular time points. This provides greater levels of regular feedback that can help you understand the implications of any changes you have made earlier.

Conclusion

The three articles we have published in this magazine should give you a good basis for moving forward and practicing evidence-based dentistry. Providing high-quality care and sustaining it is the end goal. Backing up your clinical decision-making and informing your treatment plans with evidence will inevitably help you achieve that. Hopefully the top tips in these articles help you to do that.

If you are further interested in the implementation of evidence in practice and want to be part of testing ideas more formally, then the Scottish Dental Practice-Based Research Network will be of interest to you, check out their website to find out about their current projects how to get involved.


Authors

Niall McGoldrick BDS, MFDS RCPS(Glasg); Derek Richards BDS, FDS, MSc, DDPH,FDS(DPH)


References

  1. SDCEP. www.sdcep.org.uk. [Online] 2018. [Cited: July 20, 2018.].
  2. The translation research in a dental setting (TRiaDS) programme protocol. al, Jan E Clarkson et. 57, s.l. : Implementation Science, 2010, Vol. 5.
  3. A guide to using the Theoretical Domains Framework of behaviour change to investigate implementation problems. Lou Atkins, Jill Francis, Rafat Islam, Denise O’Connor, Andrea Patey, Noah Ivers, Robbie Foy, Eilidh M.Duncan, Heather Colquhon, Jeremy M. Grimshaw, Rebecca Lawton, Susan Michie. 77, s.l. : Implementation Science, 2017, Vol. 12
  4. Scottish Government. Health and Social Care Standards. Edinburgh: The Scottish Government, 2017. 978-1-78851-015-8.

Abstract

A paediatric dental avulsion is not a clinical scenario that you will be faced with on a daily basis in general practice. Being confident in the steps required to manage a paediatric dental avulsion may reduce the stress of the situation and will allow for the most effective treatment to be provided in a timely manner. When managing a paediatric trauma, a clear, structured history and initial assessment will allow for the most appropriate treatment to be administered quickly, ensuring that no potential child protection concerns are missed. The initial assessment should establish; any head injury concerns, whom the child is with, the nature and timing of the injury and the child’s medical and tetanus status. The extra oral dry time and the stage of the tooth’s development will affect your subsequent management and the tooth’s long-term prognosis. This article is going to highlight the key factors that should be taken into consideration when assessing and managing an acute paediatric dental avulsion.


Introduction

The management of acute paediatric dental trauma within general practice doesn’t occur on a daily basis, so when it does occur it can be a daunting experience. The blood, tears & worried parents will inevitably create a more stressful encounter than a routine treatment appointment. Being confident in the initial history taking and clinical steps required to manage the patient’s care will reduce the stress and will improve the long-term prognosis of the damaged teeth. This article aims to highlight the key factors that should be considered when you are presented with a paediatric dental avulsion.

Twenty-five per cent of children experience dental trauma 1, ranging from concussion to complex dental trauma affecting multiple teeth. The maxillary incisors are most commonly affected, most commonly affecting the 7–14 age group. The main aetiology includes sport, falls and fights 2. Other factors that can increase an individual’s risk of dental trauma include; the presence of a skeletal overjet or incompetent lips 3,4.

Avulsions account for 0.5 – 3 per cent of dental trauma 5. Although they are not the most common form, they are associated with a poor long-term prognosis and the initial management can have a significant input towards the short and long-term outcomes 6,7.

From the moment the child walks through the surgery door, your initial assessment should commence. Key factors that have to be taken into consideration include; the risk of head injury, the child’s medical history and tetanus status, the nature of the injury, the time from the trauma to the replantation, the child’s social and dental history, whether the tooth has an open or closed apex, the storage medium and the risk of infection.

Having an extra oral dry time of less than an hour will significantly affect the tooth’s long-term prognosis and will influence the management of the avulsion. Furthermore, an open apex will significantly improve the tooth’s long-term survival. The loss of neurovascular blood supply to the pulp following an avulsion is detrimental to survival. The International Association of Dental Trauma (IADT) Guidelines recommends the elective root canal treatment of all permanent teeth with a closed apex to prevent infection
and resorption 8.

Non-accidental injury should also be kept in mind when assessing any child presenting with a dental trauma injury. A study looking at 390 clinical case records of children with suspected physical abuse showed that 59 per cent of children had orofacial signs of the abuse 9. It may be necessary to discuss the patient’s case with the child’s named person or with the local social work department. If you deem the child to be in imminent danger the case may require escalation to the local police service.

Head injury/airway

Has there been any associated head injury or loss of consciousness? Is the child conscious and breathing with no threat to their airway? Any concerns over potential head/ c-spine injury or any compromise to the patient’s airway will require attention from the local Emergency Department. Ask about any nausea, sickness or loss of memory that may have occurred since the time of injury and rule out these potential concerns at the start of the consultation.

Medical history

As with any consultation, any relevant medical conditions that may affect the subsequent management of the patient should be considered. Does the child have a bleeding disorder? Do they have any allergies to the metal wire you may plan to place or to the antibiotics you would consider prescribing? Are they asthmatic and already in distress over their current injury? If they are asthmatic, ibuprofen may not be an appropriate analgesia for when they are discharged home. If the child is immunosuppressed or has a cardiac defect immediate replantation may not be the most appropriate treatment option. Acute specialist input will likely be required.

These factors should all be considered before planning clinical treatment.

Haemostasis

Bleeding is often associated with dental trauma. This can be active bleeding or a clotted wound with a bloodstained face. Regardless of whether the bleeding is fresh or residual staining, this can be distressing for the patient and the accompanying adult. Active bleeding may be from a tooth socket or from an associated laceration. Once the source of the bleeding has been identified, haemostasis should be achieved through the use of local anaesthetic, pressure and sutures as required. This can be challenging if the child is already distressed. If the child has a bleeding disorder achieving haemostasis may be difficult. This may necessitate a prompt referral to secondary care.

History

When taking a history for a paediatric trauma case it is firstly important to establish who is with the child – parents, carers, teacher etc. Time should be taken to listen to the history provided from both the child and their accompanying adult.

It is very important to find out when the injury occurred. Time is of extreme importance when planning treatment and discussing prognosis. If the tooth has been avulsed, the transport medium should also be established: water, milk, saliva, dry?

Once aware of when the injury occurred it is important to carefully find out where and how the injury happened. Was the child accompanied at the time of the injury? Does the story match with the clinical presentation? Does the child’s account match the history provided by the accompanying adult? Was the environment clean or dirty? Clear documentation of this discussion is crucial.

It is important to compare the story with the injury to assess whether the two coincide. If the presentation is delayed find out if there is a legitimate reason for this delay in presentation. Follow the local practice policy to raise concerns if you are suspicious of the injury and associated circumstance. Under the new GIRFEC Guidelines, each child should have a named person. They can be contacted and the incident shared in a confidential manner if you are at all concerned.

When sharing information, the ‘golden rules’ should be followed 10:

  • Adhere to the principles of the Data Protection Act 1998
  • Share information that is necessary, relevant and proportionate
  • Record why information has been requested or shared
  • Make the child, young person or family aware of why information is being shared (unless there are child protection concerns).

Immunisations

Is the child’s tetanus up to date? They may require a booster if they are not up to date with their vaccinations or if it is out of date.

Standard vaccination protocol: The primary course of tetanus vaccination consists of three doses of a tetanus vaccination given within one-month intervals. At three years four months old the child should receive a tetanus booster. A second booster should then be given at age 14.

If in doubt, advise a medical review by their GMP.

Antibiotics

There is minimal evidence supporting the use of antibiotics following an avulsion. The prescription of antibiotics is at the discretion of the clinician. Factors that can influence this are highlighted in the British Society of Paediatric Dentistry Avulsion Guidelines 11.

  • There has been additional contamination of the tooth or soft tissues.
  • There is injury to multiple teeth, soft tissues or other parts of the body which may necessitate the need for antibiotics on their own or as a result of the combination of these injuries.
  • To facilitate the safe delivery of subsequent surgery or
  • The medical status may make the child more prone to infections.

Dental history

Find out the child’s level of dental anxiety, previous treatment and how likely they will cope with the required treatment. In this acute instance, the main priority is to replant the tooth as time efficiently as possible, if patient compliance will allow for this. It is also important to consider the subsequent treatment. If the patient is unlikely to cope with the treatment in general practice or if the treatment required involves specialist input, e.g. an MTA plug for an open apex, prompt referral will ensure no treatment delay is encountered.

Social History

When recording the child’s social history make a note of who they live with and which nursery/ school they attend. This information may be required if external services are being involved. Ensure they are registered with a GP and that you have their details.

Management

The International Association of Dental Traumatology (IADT) Guidelines 12, updated in 2012, give clear guidance on the management of paediatric trauma.
A summary is provided below:

General Trauma Advice

  • A soft diet for one-two weeks depending on the nature of the trauma
  • Avoidance of sports
  • Continuing with oral hygiene measures, using a soft tooth brush
  • The use of chlorhexidine mouthwash twice a day for seven days
  • Analgesia – paracetamol and ibuprofen as required.

Deciduous Teeth

If a deciduous tooth has been avulsed don’t replant the tooth. Discuss with the child and the parents the potential risk of damage to the permanent successor. Discuss:

  • Delayed eruption/failure of eruption
  • Decalcification
  • Discolouration.

Provide general trauma advice and arrange a review appointment.

Closed Apex

(Permanent teeth)

a) Tooth has been replanted prior to the patient’s arrival

  1. Clean the gingiva and surrounding area, ensuring there are no lacerations or associated injuries.
  2. Use clinical and radiographic assessment to ensure the tooth is in the correct position.
  3. Place a flexible splint which will be in place for two weeks.
  4. Assess tetanus status.
  5. Prescribe a course of antibiotics if deemed appropriate.
  6. Give general trauma advice.
  7. Start root canal treatment in 7–10 days.

b) Extra oral dry time <60mins

  1. Hold the tooth by the crown and gently clean the root surface using saline.
  2. Use local anaesthetic to provide suitable anaesthesia.
  3. Gently irrigate the socket.
  4.  Assess for lacerations or loose bone.
  5. Replant the avulsed tooth gently back into the socket.
  6. Use clinical and radiographic assessment to ensure the tooth is in the correct position.
  7. Place a flexible splint which will be in place for two weeks.
  8. Assess tetanus status.
  9. Prescribe a course of antibiotics if deemed appropriate.
  10. Give general trauma advice.
  11. Start root canal treatment in 7–10 days.

c) Extra oral dry time >60mins

  1. Clean any soft tissue from the tooth’s root using gauze
  2. Root canal treatment can be carried out at this stage or following reimplantation
  3. Two per cent sodium fluoride solution can be used to soak the tooth for 20 min if you have this available
  4. Use local anaesthetic to provide suitable anaesthesia
  5. Gently irrigate the socket
  6. Assess for lacerations or loose bone
  7. Replant the avulsed tooth gently back into the socket
  8. Use clinical and radiographic assessment to ensure the tooth is in the correct position
  9. Place a flexible splint which will be in place for four weeks
  10. Assess tetanus status
  11. Prescribe a course of antibiotics if deemed appropriate
  12. Give general trauma advice
  13. Start root canal treatment in 7–10 days (if it hasn’t already been carried out).

Open apex

(Permanent teeth)

a) Tooth has been replanted prior to the patient’s arrival

  1. Clean the gingiva and surrounding area, ensuring there are no lacerations or associated injuries.
  2. Use clinical and radiographic assessment to ensure the tooth is in the correct position.
  3. Place a flexible splint which will be in place for two weeks.
  4. Assess tetanus status.
  5. Prescribe a course of antibiotics if deemed appropriate.
  6. Give general trauma advice.

b) Extra-oral dry time <60mins

  1. Hold the tooth by the crown and gently clean the root surface using saline.
  2. Use local anaesthetic to provide suitable anaesthesia.
  3. Gently irrigate the socket.
  4. Assess for lacerations or loose bone.
  5. Replant the avulsed tooth gently back into the socket.
  6. Use clinical and radiographic assessment to ensure the tooth is in the correct position.
  7. Place a flexible splint which will be in place for two weeks.
  8. Assess tetanus status.
  9. Prescribe a course of antibiotics if deemed appropriate.
  10. Give general trauma advice.

c) Extra oral dry time >60mins

  1. Clean any soft tissue from the tooth soot using gauze
  2. Root canal treatment can be carried out at this stage or following re-implantation
  3. Two per cent sodium fluoride solution can be used to soak the tooth for 20 minutes if you have this available.
  4. Use local anaesthetic to provide suitable anaesthesia.
  5. Gently irrigate the socket.
  6. Assess for lacerations or loose bone
  7. Replant the avulsed tooth gently back into the socket.
  8. Use clinical and radiographic assessment to ensure the tooth is in the correct position.
  9. Place a flexible splint which will be in place for four weeks.
  10. Assess tetanus status.
  11. Prescribe a course of antibiotics if deemed appropriate
  12. Give general trauma advice.
  13. Start root canal treatment in 7–10 days (if it hasn’t already been carried out).

Summary of key learning points

  • Take a thorough history for all paediatric trauma patients taking into consideration; potential head injury, the child’s medical history and tetanus status, the nature of the injury, the time from the trauma to the replantation, whether the tooth has an open or closed apex, the storage medium, the risk of infection, any suspicion of NAI.
  • Don’t replant deciduous teeth
  • All permanent teeth with a closed apex should have a root canal treatment commenced within 7–10 days (IADT Guidelines)
  • Permanent teeth with an open apex which have an extra oral dry time > 60mins should have a root canal treatment commenced within 7–10 days (IADT Guidelines)
  • Avulsions with an extra oral dry time of <60 minutes should be splinted for two weeks (IADT Guidelines)
  • Avulsions with an extra oral dry time >60 minutes should be splinted for four weeks (IADT Guidelines)
  • General trauma advice including oral hygiene, sports avoidance and a soft diet should be given to all paediatric dental trauma patients.

Conclusion

This article has covered the key considerations required for the acute management of a paediatric dental avulsion. Following these steps will allow for the effective, timely management of your patients care, improving the long-term prognosis of the tooth and ensuring no potential child protection concerns are missed.

Authors: F. Capaldi, Paediatric Dental Core Trainee, Glasgow Dental Hospital; C. Park, Consultant in Paediatric Dentistry, Glasgow Dental Hospital


References

  1. Glendor U. Epidemiology of traumatic dental injuries – a 12 year review of the literature. Dent Traumatology 2008:24(6):603-11
  2. Gutmann JL, Gutmann MS. Cause, incidence and prevention of trauma to teeth. Dent Clin North Am. 1995;39:1-13
  3. Cortes MI, Marcenes W, Sheiham A. Prevalence and correlates of traumatic injuries to the permanent teeth of school children aged 9-14 years in Belo Horizonte, Brazil. Dental Traumatology. 2001;17:22-26.
  4. Burden DJ. An investigation of the association between overjet size, lip coverage, and traumatic injury to maxillary incisors. Eur J Orthod. 1995;17:513–7.
  5. Andreasen JO, Andreasen FM. Avulsions. In: Andreasen JO, Andreasen FM, Andersson L, editors. Textbook and color atlas of traumatic injuries to the teeth, 4th edn. Oxford, UK: Wiley Blackwell; 2007. p. 444–88
  6. Andersson L, Bodin I. Avulsed human teeth replanted within 15 inutes – a long-term clinical follow-up study. Endod Dent Traumatol 1990;6:37–42.
  7. Andreasen JO, Borum MK, Jacobsen HL, Andreasen FM. Replantation of 400 avulsed permanent incisors. 2. Factors related to pulpal healing. Endod Dent Traumatol 1995;11:59–68.
  8. Andersson L, Andreasen JO, Geoffery Heithersay et al. Guidelines for the evaluation and management of traumatic dental injuries. II. Avulsion of permanent teeth. Dent Traumatology 2013. V 3 7 / N O 6 1 5 / 1
  9. Cairns A, Mok J, Welbury R. Injuries to the head, face, neck and mouth of physically abused children in a community setting. International Journal of Paediatric Dentistry. 2005 vol 15, 5 310 – 318.
  10. Scottish Government. 2018. GIRFEC information sharing. [ONLINE] Available at: https://www.gov.scot/ [Accessed 30 August 2018].
  11. P. F. Day, T. A. Gregg. Treatment of avulsed permanent teeth in children. British Society of Paediatric Dentistry Guidelines 2005.
  12. International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 2. Avulsion of permanent teeth Dental Traumatology 2012;28:2 88-96

With the introduction of the first intraoral scanner, CEREC (Chairside Economical Restoration of Esthetic Ceramics) by Dentsply Sirona in 1985, dentistry was offered an exciting alternative to conventional means of impression-taking. Since then, digital technology has developed, resulting in faster, more accurate and smaller scanners than ever before.

As of writing, approximately 15 separate intraoral scanners are available from a variety of companies – all competing within a fierce, growing market. In 2014, the global intraoral scanner market was valued at US$55.3 million, estimated to expand with an annual growth rate of 13.9 per cent from 2015 to 2022 1.

Intraoral scanners have gained traction within the orthodontic speciality, with restorative dentistry following suit. Intraoral scanning technology aims to address fundamentally multiple contemporary clinical issues, including the intuitively error-prone volumetric changes of impression materials and the expansion of dental stone.

This review will provide an overview of the advantages, limitations and clinical applicability of intraoral scanners and serve as an introduction for those unfamiliar with this technology.

Firstly, it is pertinent to discuss the technology of intraoral scanners. The objective of an intraoral scanner is to record precisely the 3D geometry of an object, to allow this to be subsequently used to produce customised dental devices. The fundamentals of intraoral scanning relate to structured light being cast upon an object to be scanned by a handheld device. Images of the object of interest are then captured by image sensors within the handheld scanner and processed by software. This results in the production of a point cloud which is further analysed by software to create a 3D surface model, also known as a mesh 2. The most widely used output file is the STL (stereolithography/standard tessellation language 3).

Numerous technologies exist to process scan data including: triangulation, confocal, active wavefront sampling (AWS) and stereophotogrammetry.

Triangulation works by the concept that the point of a triangle (object of interest) can be calculated knowing the positions and angles of images from two points of view.

Confocal technology relates to the acquisition of focused and defocused images from selected depths – the sharpness of the image infers distance between points and is related to the focal length of the lens 4.

AWS needs a camera and an off-axis aperture module. The module moves around a circular path centred on a point of interest – the distance and depth information are derived from a pattern produced by each point5.

Stereophotogrammetry estimates all co-ordinates through analysing images using an algorithm – relying on passive light projection and software as opposed to active light projection and expensive hardware.

Advantages Limitations
Enhanced patient comfortInitial learning curve
Gag reflex managementUnable to displace soft tissue – marginal inaccuracies
No physical study models requiring storageExpensive hardware/annual software agreement
Streamlined workflowUnpredictable for extended edentulous sites
Predictable for single teeth/implants/short span bridgework (<5 units)Unable to register dynamic soft tissue relationships
Immediate preperation feedback in high magnification (undercut/margin depths)Requires laboratory familiar with digital technology
Improved patient communication

No matter the imaging processing technology, this data is then constructed into a virtual 3D model. The major challenge of this is rendering a point of interest taken at multiple angles. Accelerometers within the handheld scanner allow distances and angles to be measured between images, with extreme points eliminated statistically, culminating in the production of an STL file suitable for further use to create the custom dental device6.

The accuracy of an intraoral scan is paramount for a well-fitting custom dental prosthetic. This is assessed through the values of “trueness” – being the measured deviation from the actual value and “precision” – the repeatability of multiple measurements.

These terms were defined by the International Organization for Standardization – standard 5725-1. Studies investigating the accuracy of intraoral scanners should ideally include both measurements, to adequately represent both how “correct” a scanner is, as well as how predictably similar its measurements are.

In 2016 8, Ender and co-workers, and other studies, demonstrated intraoral scanner trueness of between 20 m and 48µm and precision between 4µm and 16µm 9-11.

Later, in 2017, Imburgia et al 7 reported scanner trueness and precision in the region of 45µm and 20µm respectively for the most accurate scanners tested. To put these figures into perspective, conventional impression trueness and precision is generally reported in the region of 20µm and 13µm respectively12-14. In its totality, the literature currently reports intraoral scanning is at least as accurate as conventional methods of impression-taking, subject to the complexity of the clinical case 11,15,16.

A common finding is that of partial scans being the most reliable and accurate, when compared to full arch scans2,17,18. When scanning over five units (implants or teeth), the data would suggest scanning is not as predictable as conventional impressions7.

Full arch scans are shown to suffer distortion, specifically at the distal end of the scan 17, 19, 20. Therefore, the scanning of extended preparations or the edentulous mandible is at high risk of error. Shorter scan distances therefore yield the most accurate results9, 21. A clinically acceptable marginal gap for an indirect restoration may be defined at below 100µm22-25.

It is evident that intraoral scanners can achieve errors of consistently less than this value (in single tooth and limited span situations), giving clinical validity.

Advantages

Intraoral scanning provides many advantages for the clinician within single unit, tooth or implant supported restoration or full arch appliance (such as orthodontic retainers or aligners 26-28) situations. Digital records of the patient obviate the need to store plaster models. This has positive implications for storage and consumable costs 27. This data also allows the clinician to easily and accurately monitor changes within the dentition over time – for example, tooth wear or orthodontic relapse 5. It has been evidenced by multiple authors7, 11, 27, 29. that intraoral scanning results in less patient discomfort compared to conventional impressions.

Patients also prefer scanning to conventional methods of impression-taking 28,30 and gag reflexes can be avoided. There is a modest improvement in chairside time 30,31 with a reported average scan time of between four and 15 minutes4, however, greater time saving is gained through the elimination of certain following laboratory steps. A small quadrant scan is ideal for a single restoration 9,32.

Scans of prepared teeth can be scrutinised by the clinician at extreme magnification and software overlays of undercuts/preparation depths are available, with potential for improved clinical outcomes as a result. Files can be directly emailed to the laboratory – thus avoiding the need to physically post an impression. The dental technician can also assess the impression in real time and request another scan to be taken – avoiding an extra visit for the patient 33,34.

Certain problematic sections can be retaken thus avoiding the need to retake a full impression. Patients are shown to feel more involved with treatment and are interested in scanning technology – serving as a good advertising tool35-37.

Limitations

Limitations exist within the practice of intraoral scanning however. As previously mentioned, scanning is currently predictable only within limited parameters. Full arch implant retained prostheses, extended bridgework and complete dentures are currently not supported by compelling evidence. In relation to complete dentures, a predictable dynamic impression of soft tissue borders, muscle attachments and mucosal compressibility is currently severely limited by technology 2.

There is an accepted learning curve in relation to intraoral scanning. It has been reported that subjects with a greater affinity for the world of technology will find the technology easier to adopt than those without this affinity 36,38,39. Issues arise in the detection of deep margins of prepared teeth39 as light cannot record the ‘non visible’ areas of the preparation 2 as normally conventional impression material may be able to displace the gingival margin and record valuable data, following the retraction process. As with conventional impressions, blood or saliva may obscure important margins 40.

With good technique and speed, it has been reported one can overcome many of the reported limitations15,29. The issue of reflective restorations or teeth may also arise. This can result in disruption of the matching of points of interest within the software – resulting in an inaccurate 3D model. This can be counteracted by changing the orientation of the scanner to increase diffuse light, using a camera with a polarizing filter or coating the teeth in powder. Powder coatings (aluminium oxide) can add a variable thickness of up to 90µm41 and further issues arise if taking a full arch scan as powder inevitably gets mixed with saliva – resulting in time spent cleaning teeth and reapplying powder 29.

The scan path can also affect the quality of the scan42 and can result in lost tracking. This should ideally be at a constant distance from the point of interest and moved in a fluid manner, avoiding jerky or fast movements – this can be clinically challenging6. When scanning and tracking is lost, one should return to an area easily recognisable by the software – for example, the occlusal surface of a molar – to predictably re-establish tracking. If scanning a complete arch, multiple small interocclusal records appear to be the most predictable method of achieving accurate articulation or a small scan of the anterior sextants, as described by a 2018 study 32.

The initial expense and management costs of hardware may also be prohibitive – the average intraoral scanner costs between £13,000 and £31,000. An annual update agreement may also exist to “unlock” STL files for use of the laboratory – this again has an associated cost.

As more scanners reach the market, it is likely these costs will become more competitive and attractive to new adopters.

Conclusion

In conclusion, intraoral scanning presents a viable alternative to (and occasionally outperforms) conventional impression techniques within the confines of strict case criteria. Despite being in its late “innovator” and “early adopter phase”, intraoral scanning has shown great potential within restorative dentistry, orthodontics and more recently guided implant surgery (combined with CBCT) 43. Many of its limitations can be circumvented with good clinical technique. Technology, potentially prohibitive costs and market inertia currently prevent its routine use in a wide array of clinical situations.


Author

M Paterson, Specialty Registrar in Restorative Dentistry/Honorary Clinical Lecturer,
Glasgow Dental Hospital & School

 


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Arvind Sharma, BDS(Dund), MSc(Endo), MJDFRCS(Eng), MFDSRCPS(Glas)


Arvind Sharma presents the second and final part of a structured critical review to evaluate the question whether the use of cone beam computed tomography (CBCT) in endodontics has an influence on clinical decision-making.

Methodology

The methodology of this review is based on the aforementioned steps, as suggested by Boland et al 2014. Below is a brief summary of the methods used.

The following structure was therefore employed:

  1. Inclusion criteria
  2. Exclusion criteria
  3. Search engines
  4. Search strategy with literature search
  5. Study selection
  6. Quality assessment
  7. Data extraction.

The topic considered was discussed with my supervisor and also with my peers to solicit their views.

The author attended a British Endodontic Society conference held in London in March 2015 and met Dr Patel (one of the speakers that day) when the topic of this review was discussed.

The author and Dr Patel corresponded by email, and Dr Patel suggested that there is a lack of evidence in this field due to lack of clinical studies and suggested that a systematic review would be difficult in his opinion. This led the author and his supervisor to consider a structured critical review instead.

Due to the aforementioned reasons and since the author’s time and resources are limited, a traditional systematic review was not possible. It was decided, therefore,  to design and conduct a structured critical review of the literature to answer the question posed.

F&T LevelStudies Identified
3-Diagnostic Thinking Efficacy4
4-Therapeutic Efficacy3
5-Patient Outcome Efficacy1

Table 4: Summary of included studies with associated F&T hierarchy levels

 

The review question was then formalised as a statement of my intention of the structured critical review. This was developed from what was found through the available evidence to what I further planned to find out. A theoretical approach, exploring factors that lead to a process, was to be taken.

Results

The search identified eight publications that qualitatively or quantitatively assessed the use of CBCT in endodontics combined with clinical decision-making with respect to three levels of a six-tiered hierarchical model. (Level 3 diagnostic thinking efficacy, Level 4 therapeutic efficacy and Level 5 patient outcome efficacy).

The following table (table 3), shows the final eight papers that were included in this study along with the F&T hierarchy levels.

As can be seen from the above table (table 4), four papers were identified investigating the diagnostic thinking efficacy, three papers investigating the therapeutic efficacy and one paper investigating patient outcome.

Of all the eight studies, six concluded that CBCT made an influence in clinical decision-making and two  did not.

Meta-analysis

A meta-analysis was not performed. Only a narrative summary of the data is presented since the included studies did not meet the criteria for conducting a meta-analysis. The differences across the trials, including inconsistent patient characteristics presented in some of the papers, small sample sizes, diversity in protocols (interventions and comparators were not uniform across all studies), and the inconsistency in reporting outcomes (not all studies reported the same results), including statistical data (not present in one study), precluded a statistical synthesis of the included trial results.

Discussion

The aim of this structured critical review was to answer the question, “does the use of CBCT in endodontics influence clinical decision making?” Of the eight studies chosen for this review, 75 per cent concluded that CBCT did influence decision-making whereas 25 per cent of studies concluded that CBCT did not influence clinical decision-making.

From the evidence analysed in this review, CBCT appears to have a positive influence in clinical decision-making in endodontics. However, when data was extracted, the six studies (75 per cent) did show limitations, which will be discussed below.

Although the literature search provided an abundance of evidence on CBCT, the evidence available relating to the review question was limited. When considering the hierarchy of evidence (randomised controlled trials being the most robust form of study) and application of the inclusion criteria to the results of the searches there was a lack of studies in this area with only nine studies meeting criteria. One of the reasons for this is due to ethical considerations in relation to the exposure of patients to radiation when taking a CBCT for an in-vivo trial/study. So, although CBCT is being more commonly used in clinical endodontic practice, the number of in-vivo studies is lacking. This was further confirmed by personal communications with the well-published author and committee member of the European Society of Endodontology, Dr Shanon Patel.

The limited literature search was further compounded by the fact that Fryback and Thornbury Levels 3, 4 and 5 were applied and this resulted in fewer relevant studies. A number of studies were found but were mainly on levels 1 (technical quality of image) and 2 (diagnostic accuracy, sensitivity and specificity). The inclusion criteria of human, English language and in-vivo studies again limited the number of studies since published animal and foreign language studies were excluded. Applying a search for ‘all studies’ gave a wider net for the search with non-relevant studies due to their hierarchical level of evidence being excluded. This was the case with Kurt et al 2003, which was a cross-sectional observational study.

Considering the available studies, the author believes that all or at least a representative sample of the available evidence relating to the study question was obtained.

StudyStudy TitleF&T Levels
1. Abuabara et al 2012Efficacy of clinical and radiological methods to identify second mesiobuccal canals in maxillary first molars3
2. Balasundaram et al 2012Comparison of Cone-beam computed tomography and periapical radiography in predicting treatment decision for periapical lesions:
a clinical study
3
3. Davies et al 2015The detection of periapical pathoses using digital periapical radiography and cone beam computed tomography in endodontically retreated teeth-part 2:
a one- year post-treatment follow-up
3 + 4
4. Ee et al 2014Comparison of endodontic diagnosis and treatment planning decision using cone-beam volumetric tomography versus periapical radiography4
5. Hashem et al 2015Clinical and radiographic assessment of the efficacy of calcium silicate indirect pulp capping: a randomised controlled clinical trial3
6. Kurt et al 2014Outcomes of periradicular surgery of maxillary first molars using a vestibular approach: a prospective, clinical study with one year of follow-up5
7. Mota de Almeida et al 2014The impact of cone beam computed tomography on the choice
of endodontic diagnosis
4
8. Mota de Almeida et al 2014The effect of CBCT on therapeutic decision-making in endodontics4

Table 3: The final eight papers included in this study

 

Overall, on a hierarchy of evidence, since only two randomised controlled trials were included, the evidence gathered was not of the highest calibre. The included studies all had limitations that were either discussed by the individual authors or were identified during this review’s quality assessment process. The limitations identified included, small sample sizes in most studies, history and clinical information (signs and symptoms) not always provided, the number and clinical experience of observers varied from novice to most skilled, the radiation dose used with the CBCT modality was not always validated, the resolution of CBCT images was not always discussed as image enhancement may or may not have affected the image quality and hence results and detailed statistical data were not disclosed in three studies.

In one study where periradicular surgery was being performed, a microsurgical approach was not used, which is now accepted as the gold standard in retrograde endodontics, both in Europe and North America. The ability, for example, to identify artefacts due to beam hardening that could be misdiagnosed as a carious lesion is an important point. Therefore, image interpretation is still an area that requires further training especially for less experienced clinicians.

There were limitations with this structured critical review study with respect to the time that was spent on the literature search, the final selection of the chosen studies, the quality assessment and data extraction. This was mainly due to the part-time nature of this study and there only being one individual, namely the author, executing the various stages of this structured critical review.

It is the author’s opinion that by having more than one individual working on various aspects of this study, bias may have been eliminated, leading to a more rigorous study process.

The limitations were related to the methodological part of this study. Specifically:

  • Inclusion/exclusion criteria-language bias, publication bias was considered in a limited way with the use of one researcher
  • Literature search resources – three search engines only being employed
  • Search strategy – one researcher, using mainly electronic databases only and study selection
  • Quality assessment only being performed by one researcher
  • Data extraction only being performed by one researcher and was not cross-checked by another person. However, data was put aside for one week and then checked again to compare that the sets of the data were the same.

With all of the above limitations considered, it is the author’s opinion that a thorough and reproducible literature search was performed using appropriate and relevant search terms, quality assessment of the chosen studies enabled the most appropriate studies to be used for data extraction purposes and since the conclusions reached for this critical review process are similar to other reviews in this field of study, the author is confident that the review process was conducted with appropriate methodology, is clear, reproducible, thorough and transparent.

Although the overall findings of this review seem to suggest that CBCT is influential in clinical decision-making, it is the author’s opinion that the findings cannot be generalised and applied to the everyday clinical practice of endodontics. There was disparity in the studies in terms of their design, sample size, age range, male-female ratio, setting, sample definition, F&T level, examiners used (experience and number of) and use of statistical data, which means it is difficult to make an absolute comparison of outcomes and reach a definitive conclusion based on the chosen studies. CBCT does have an important place in endodontic clinical decision-making but its use should still be limited as ESE recommend.

In conclusion, this critical review has shown that although most of the available evidence appears to show that CBCT does influence clinical decision-making in endodontics, high-quality longitudinal studies are lacking, and more research is required. Based on the current available evidence, the ESE guidelines seem appropriate and should be applied accordingly. The studies by Balasundaram et al 2012, Davies et al 2015 and Mota de Almeida et al 2014 all looked at the detection of periapical radiolucencies and, as discussed earlier, did not concur with their results. CBCT has a useful place in clinical decision-making in endodontics but its use should be kept for complex cases where radiographs do not give sufficient information. This would resonate with the ESE guidelines.

As discussed earlier, there are implications in using CBCT, namely, cost of equipment, training required for the use and interpretation of CBCT and importantly the radiation dose the patient is exposed to. No doubt, CBCT can be relevant and useful in endodontics and can have an influence in clinical decision-making, which in turn may help a patient with complex symptoms that routine investigative methods have proved limited. However, the overall consensus of the studies do not recommend the routine use of CBCT in endodontics but recommend its consideration when other methods of diagnosis prove to be inconclusive in reaching a definitive diagnosis. Again, this would in line with guidelines produced by the ESE. Looking into the future, if CBCT equipment can expose the patient to less radiation, perhaps in line with the amount produced by intra-oral radiographs, its use may well increase particularly if coupled with a more affordable price tag. Increasing CBCT education at undergraduate and postgraduate level would improve knowledge and application in the clinical setting. This would ultimately give the clinician more tooth detail, which could in turn improve patient care and the reputation of endodontics as a dental discipline amongst patients.

Conclusions

This structured critical review has shown that there is limited evidence on the influence of CBCT in clinical decision-making in endodontics. The available evidence does however seem to suggest that there is a place, although limited, for CBCT use in endodontics with decision-making. Application of ESE guidelines should be followed until further research can be carried out in this interesting and clinically relevant imaging modality


Verifiable CPD questions

Aims and objectives

To give the reader an understanding of CBCT as a modern imaging tool and its application in endodontics

To provide details of the evidence surrounding clinical decision making in endodontics

To highlight the clinical applications where use of CBCT in endodontics would be advantageous

Learning outcomes

To understand the basics of how CBCT works
and its clinical application in endodontics

To be able to recognise when the use of CBCT
may help clinical decision-making

Example question

What kind of process was used to carry
out the research?

a) Systemic review?

b) Randomised controlled trial?

c) Structured critical review?

d) Questionnaire?

How to verify your CPD

Go online to www.sdmag.co.uk and click on the CPD tab to access all our CPD Q&As and certificates.


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LOFTHAG-HANSEN, S., HUUMONEN, S., GRNDAHL, K. and GRNDAHL, H., 2007.Limited cone-beam CT and intraoral radiography for the diagnosis of periapical pathology. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, 103(1), pp. 114-119.

MOTA DE ALMEIDA, F J, KNUTSSON, K. and FLYGARE, L., 2014. The effect of cone beam CT (CBCT) on therapeutic decision-making in endodontics. Dentomaxillofacial Radiology, 43(4), pp. 564-572, (20130137).

MOZZO, P., PROCACCI, C., TACCONI, A., MARTINI, P.T. and ANDREIS, I.B., 1998. A new volumetric CT machine for dental imaging based on the cone-beam technique: preliminary results. European radiology, 8(9), pp. 1558-1564.

NG, Y., MANN, V. and GULABIVALA, K., 2010. Tooth survival following non-surgical root canal treatment: a systematic review of the literature. International endodontic journal, 43(3), pp. 171-189.

PATEL, S., WILSON, R., DAWOOD, A. and MANNOCCI, F., 2012. The detection of periapical pathosis using periapical radiography and cone beam computed tomography–Part 1: pre-operative status. International endodontic journal, 45(8), pp. 702-710.

PATEL, S., DURACK, C., ABELLA, F., ROIG, M., SHEMESH, H., LAMBRECHTS, P. and LEMBERG, K., 2014. European Society of Endodontology position statement: The use of CBCT in Endodontics. International endodontic journal, 47(6), pp. 502-504.

PATEL, S., DURACK, C., ABELLA, F., SHEMESH, H., ROIG, M. and LEMBERG, K., 2015. Cone beam computed tomography in endodontics–a review. International endodontic journal, 48(1), pp. 3-15.

POPE, O., SATHORN, C. and PARASHOS, P., 2014. A comparative investigation of cone-beam computed tomography and periapical radiography in the diagnosis of a healthy periapex. Journal of endodontics, 40(3), pp. 360-365.

REIT, C. and KVIST, T., 1998. Endodontic retreatment behaviour: the influence of disease concepts and personal values. International endodontic journal, 31(5), pp. 358-363.

RIGOLONE, M., PASQUALINI, D., BIANCHI, L., BERUTTI, E. and BIANCHI, S.D., 2003. Vestibular surgical access to the palatine root of the superior first molar: “low-dose cone-beam” CT analysis of the pathway and its anatomic variations. Journal of endodontics, 29(11), pp. 773-775.

ROSEN, E.D., TASCHIERI, SILVIO D D S, DEL FABBRO, M., BEITLITUM, I.D. and TSESIS, I.D., 2015. The Diagnostic Efficacy of Cone-beam Computed Tomography in Endodontics: A Systematic Review and Analysis by a Hierarchical Model of Efficacy. Journal of endodontics, 41(7), pp. 1008-1014.

SACKETT, D.L., ROSENBERG, W.M., GRAY, J.A., HAYNES, R.B. and RICHARDSON, W.S., 1996. Evidence based medicine: what it is and what it isn’t. BMJ: British Medical Journal, 312(7023), pp. 71.

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Day One

Ms B attends as a new patient at a local dental surgery complaining of sensitivity in a number of teeth. A dental associate – Mr W – arranges bitewing radiographs and these show extensive distal caries at LR6 and caries in a number of other teeth. He advises that LR6 is of most concern and recommends treatment by an amalgam filling, given the size and depth of the caries. Ms B insists on a composite filling as it looks more “natural”. Mr W agrees but records his discussion with the patient regarding the pros and cons of composite versus amalgam filling in this particular case.

Day Seven

Mr W places an extensive composite filling at LR6 but moisture control is difficult as Ms is intolerant of dental dam, has excess saliva and there is gingival bleeding due to the size of the cavity. Ms B is also phobic and “fidgety” and keeps closing her mouth. Mr W informs the patient that given the extent of the cavity and difficulty of the procedure, root canal treatment (RCT) may be necessary in the future if the tooth does not “settle”. Ms B is also advised that a small amount of decay remains, again due to the size of the cavity.

Four months later

Ms B attends a different dentist complaining of pain in LR6. The dentist also notes untreated caries in three other teeth. A radiograph reveals decay under the filling at LR6 and the dentist undertakes the first stage of RCT and the tooth is appropriately dressed.

Two weeks later

The patient returns to the new dentist and undergoes root canal treatment on LR6 and another appointment is scheduled to carry out further restorations on the other untreated caries, including crowning of LR6.

A letter of claim for clinical negligence is received by Mr W from solicitors acting on behalf of Ms B. It alleges incomplete removal of caries at LR6 and also inadequate moisture control resulting in a reduced bond in the composite filling causing recurrent caries and chronic pain with later irreversible pulpitis necessitating root canal treatment.

Ms B claims damages amounting to the cost of the RCT and crowning of LR6 as well as loss of earnings due to time off work due to chronic pain.

MDDUS obtains copies of the patient notes and all relevant radiographs and sets out a letter of response based on a detailed case report. It is argued that Mr W carried out the initial restoration on LR6 in very challenging circumstances and to the best of his ability – as would any reasonable and competent general dental practitioner.

Moisture control was difficult given the problems of a phobic patient, restricted access and intolerance of dental dam. Mr W used high aspiration, cheek retraction and cotton wool to absorb moisture the best he could. To the extent there may have been a reduced bond this was more likely to do with the extent of the cavity and use of a composite filling rather than amalgam as was advised by the dentist. Amalgam may not be as aesthetically pleasing, but it will restore a tooth even in the presence of moisture whereas with composite materials moisture control is essential as bonding is actively to the tooth substance.

In regard to causation, MDDUS argues that the root canal treatment could not be the result of any act or omission by Mr W. The patient presented with extensive caries in LR6 and rejected the dentist’s advice on an amalgam filling and – on the balance of probabilities – would have thus required root canal treatment at LR6 in any event.

It is clear that not all the decay was removed in Mr W’s restoration of LR6, but it would not be unreasonable to leave some decay, restore the tooth appropriately, advise the patient accordingly and keep the tooth in question under review both clinically and radiographically.

MDDUS sends the letter of response and receives notification that the case is being dropped.

Key points

  • Keep records of discussions with patients in support of shared decision-making and consent.
  • Advise patients of likely prognosis even with adequate treatment.
  • Consider being more proactive in advising patients on the “best” treatment option.

 


About the author

Aubrey Craig is head of dental division at MDDUS. For more information, go to www.mddus.com

Due to its powerful regenerative properties, platelet rich growth factor Endoret (PRGF) is being increasingly used in many fields of medicine, such as plastic surgery and dental implantology.

It has been shown to reduce scarring, rejuvenate damaged facial tissue, and accelerate wound healing. Endoret (PRGF) is proven to promote angiogenesis, cell migration, cell proliferation and the secretion of growth factors active in the wound healing cascade, while at the same time decreasing inflammation and pain.

Through this simple case report, I would like to show how Endoret (PRGF) can be applied in the field of dental implantology to make treatment outcomes more predicable by optimising healing conditions.

Preparation of platelet rich growth factor (Endoret)

Step one is to collect a small quantity of the patient’s blood. Four collection tubes, each containing 9ml of blood, are filled. A total of 36ml is usually sufficient for most implant cases (Fig 1) However, in larger cases where more augmentation is required it is usual to collect eight tubes (72ml).

Once the blood has been collected, the patient is asked to return to the waiting area while the fractionation process is carried out which takes about 15 minutes. The collection tubes are transferred to the centrifuge machine (Fig 2). At the end of the eight-minute cycle, the collection tubes are immediately returned to their stand. It is important that this is done carefully with minimal disruption to the blood, which is now separated into four distinctive bands.

Each tube is now marked. The erythrocytes are heaviest and lie in the bottom half.

Next is a thin buffy layer approximately 0.5cm thick. This is the leukocyte fraction which must be avoided as these cells will evoke pain and inflammation.

In the top half of the tube is the liquid fraction of interest. Concentrated in platelets, plasma and growth factors, this straw-coloured layer is itself divided into two fractions: 1 and 2.

While fraction 1 (F1) is richer in the fibrin, which will create the collagen matrix for wound healing, fraction 2 (F2) contains the greatest concentration of platelets and protein markers. It is these protein markers which signal to the regenerative cells and trigger their activity.

Marking each tube, a safe distance of 0.5cm from the visible upper limit of the buffy layer, you then measure two centimetres up and mark the tube again. This threshold divides the most superior layer F1 from the second layer F2 (Fig 3).

Using the plasma transfer device, F1 and F2 are then separated into labelled collection tubes F1 and F2. Without activation, these fractions will remain viable for up to four hours.

At this point, I will normally ask for the patient to return and we follow the usual asepsis protocol for surgery and deliver the local anaesthetic and or intravenous sedation where required. When placing implants, I always require two dental surgery assistants, one sterile and the other non-sterile.

Depending on the planned length of the procedure, I will indicate to my assistants when F1 and F2 should be activated with calcium chloride (Fig 4). Once activated the fractions are transferred into sterile glass bowls and placed into a special oven that incubates them at body temperature for 15-25 minutes (Fig 5).

Endoret (PGRF) is used in three distinct forms. There is the clot (F2), into which autogenous bone collected during implant site preparation is added, and also xenograft in situations where more augmentation is required (Fig 6).

There is the fibrin membrane (F1), which is placed on top of F2 (Fig 7). This stimulates fibroblasts which accelerates wound closure and often creates thicker mucosal biotype.

The liquid form of Endoret (PRGF) is used to promote healing after ridge-splitting procedures, and to improve implant integration by up to 40 per cent when the implant surface is coated immediately before placement.

In this simple case, all three forms of Endoret (PRGF) were used to achieve a small lateral augmentation of the implant site, as well as promote osseointregration of the implant and wound closure by primary intention.

A number 15 scalpel was used to make a palatally inclined incision at the site of the missing upper right first premolar. This cut was extended mesially and distally around the adjacent teeth without relieving incisions.

A number 12 scalpel was then used to make a periosteal releasing incision in the pocket flap created being mindful of the proximity of the infra-orbital nerve.

After the creation of the pilot hole using a drill with irrigation at 1800rpm, the remainder of the osteotomy was created following a biological drilling protocol advocated by Professor Eduardo Anitua, Scientific Director of BTI Biotechnology Institute.

This involves preparation without irrigation at speeds of between 50 and 150 rpm. A high level of control can be maintained at these low speeds while biologically viable autogenous bone debris can be collected from the drill flutes, which is transferred to the F2 for later augmentation.

Immediately before implant placement, the selected implant’s entire surface was dipped in liquid Endoret (PRGF). The liquid was also injected into the osteotomy. Engine placement of the Implant then proceeded as per normal protocol.

Lateral augmentation was completed easily and safely without the need for a membrane and in this case, without xenograft either. The F2 clot containing the collected autogenous bone drill debris was first placed against the bone (Fig 8). In situations where more lost bone volume needs to be replaced, a second clot of F2 containing xenograft is layered on top of the autogenous layer. Finally, the F1 fibrin membrane was placed on top (Fig 9).

The wound was closed with three interrupted sutures, which were removed after four days (Fig 10).

The autologous nature of Endoret (PRGF) means it has many applications in dentistry beyond the simple implant case described here.

In the atrophic maxilla where residual bone height below the sinus is very low, Endoret (PRGF) in combination with short implants can be used in a transalveolar elevation approach to gain 2-3mm of additional bone height very safely. Such an approach is now being used widely to avoid more traditional and invasive methods such the lateral window technique.

In the field of oral surgery accelerated and improved healing has obvious benefits; for example, the avoidance of dry socket through socket preservation with Endoret (PRGF), and the treatment of bisphosphonate osteoradionecrosis where necrotic bone has been resected.

Combining Endoret (PRGF) with traditional guided bone regeneration procedures significantly reduces the incidence of wound dehiscence as well as eliminating the need for costly and technique sensitive collagen membranes. When mixed with xenografts such as Bio Oss, Endoret (PRGF) will attract the osteogenic cells necessary to promote true bone formation.

Backed up by more than 15 years of research, and with more than 700,000 patients treated from 20 countries without adverse effects being reported, the applications for Endoret (PRGF) in surgical dentistry are wide-ranging, predictable and safe.

 


About the author

Dr Jerome P Sullivan BDS, DipImpDent RCS (Eng), PG cert sed UCL qualified from Manchester University in 1993. He graduated with a diploma in dental implantology from the Royal College of Surgeons (UK) in 2011 and was awarded an inaugural gold medal for the high standard of his clinical cases. He has become increasingly involved in the field of platelet rich growth factor, and he now uses this technique to deliver implant solutions to patients with complex dental needs

 


More information

For more information please contact Info@gracefielddental.ie

Periodontitis is a term that refers to a heterogeneous group of diseases characterised by loss of the tooth-supporting tissues. It is well established that periodontal diseases are of an infectious nature and the impact of dental plaque biofilms on the etiology of periodontal diseases has been studied in details. In fact, certain bacterial pathogens are considered to play a significant role in the pathogenesis of periodontitis, formation of the periodontal pocket, destruction of the connective tissue and resorption of the alveolar bone.

Therefore, the primary cause of periodontitis is bacteria, and when the quantitative and qualitative change in bacterial composition in the oral cavity is such that homeostasis cannot be maintained any longer, the host response appears to be impaired and the activity of the tissues become abnormal.

A publication from Hasturk et al. (2007) outstandingly defined the possible pathogenesis of the periodontal infections; in fact, Hasturk and co-workers suggested that while the etiology of periodontitis is bacteria, the pathogenesis is inflammatory.

In other words, the interaction between the pathogenic bacteria and the host’s defence system could lead to the development of an inflammatory process.

Once periodontitis is established, the inflammatory infiltration of periodontal tissues is composed of different immunological cell types. These cells produce a large repertoire of specific types of cytokines and chemokines, which could play a significant role in the pathogenesis of periodontitis. Some of these, together with the end products of periodontal tissue destruction, could act as possible biomarkers and eventually could have diagnostic value by identifying patients with enhanced disease susceptibility and sites with active disease. They could also serve as surrogate end points for the monitoring of the patient treatment effects and treatment status, to tailor the maintenance care based on the biological needs of the subjects.

These biological mediators could support the clinical measurements already used in the routine diagnosis of periodontal diseases such as probing pocket depth, bleeding on probing, clinical attachment levels, plaque index and radiographs quantifying alveolar bone level. Nevertheless, they are often of limited usefulness because they are indicators of previous periodontal disease rather than the present disease activity. In addition, current periodontal examination procedures performed at single visit cannot determine whether or not sites are currently undergoing additional attachment loss.

As various immunopathogenic mechanisms are involved in the disease process of periodontitis, a combination of indicators is needed to improve the specificity of periodontal disease diagnosis. On the basis of the current understanding of the complexity of periodontitis, the identification of one single diagnostic marker for all forms of periodontal disease seems illusionary.

Nevertheless, researchers have been searching actively for unequivocal markers of periodontitis in different biological sources such as blood or serum, subgingival plaque sample, gingival crevicular fluid (GCF) and saliva to develop a simple test, to be used as chairside test or home-use device, to determine whether a patient suffers from periodontitis and needs therapy, as opposed to another patient who needs no intervention even though he/she has gingivitis and/or to establish a “custom-made” frequency of recall appointments.

The aim of this literature review is to summarise data from the literature on periodontal disease markers with special focus on saliva.

Saliva and candidate biomarkers of periodontal diseases

Saliva is a mirror of the body that contains a large number of proteins and peptides that are responsible for maintaining the integrity of the oral cavity (see table opposite page).

Saliva also meets the demand for inexpensive and easy-to-use diagnostic aids due to the non-invasive and simple nature of its collection. It can be collected with or without stimulation. The collection of gland specific saliva (from parotid, submandibular and sublingual gland) can allow differences in the amount of fluid and constituents of each gland to be determined. Differently, whole saliva consists of a mixture of oral fluids, and includes secretions of the major and minor salivary glands and constituents of non-salivary origin, such as derivates from GCF, serum and blood cells in case of bleeding gingiva or oral wounds, and expectorated bronchial secretions. It might also contain bacteria, bacterial products, viruses, fungi, desquamated epithelial cells and food debris.

The use of saliva for diagnosis of periodontal disease activity has been the subject of considerable research activity; in fact, it contains locally and systemically derived markers of periodontitis, thus offering the basis for a specific test. Several potential markers have been investigated to produce an assay system suitable for use in dental practices.

The main candidates in the search for biomarkers of periodontal disease activity fall into different general categories:

  1. Inflammatory and immune products
  2. ost-derived enzymatic and non-enzymatic proteins
  3. 3 Connective tissue degradation products
  4. 4 Products of bone resorption
  5. 5 Human salivary proteome and transcriptome
  6. 6 Substances associated with putative pathogens.

Inflammatory and immune products

While the bacterial infection triggers the destructive process, the host immune response to the bacterial challenge is responsible for the molecular processes leading to periodontal tissue destruction. The interaction between the pathogenic bacteria and their (toxic) components and the host defence system could lead to the development of periodontal pockets, loss of connective tissue, and bone resorption. Once periodontitis is established, the inflammatory infiltration is composed of different cell types, such as neutrophils, T and B lymphocytes, and macrophages migrating into the perivascular connective tissue.

The substances released by the inflammatory immune cells as well as by resident fibroblasts endothelial cells and others during the disease process include a large repertoire of molecules, such as antibodies, complement proteins, acute phase proteins and a broad range of inflammatory mediators (i.e. cytokines, chemokines, arachidonic acid metabolites etc.).

A recent investigation found that salivary level of MIP-1α was significantly correlated with Aggregatibacter actinomycetemcomitans positive students who developed periodontal disease six to nine months before radiographic detection of bone loss. MIP-1α level was also significantly associated with increasing probing depth and the number of pockets > 6mm (Fine et al. 2009).

Host-derived enzymatic and non-enzymatic proteins

Non-enzymatic proteins have been examined in a number of studies to investigate whether or not there was a relation between periodontal disease and these proteins in saliva. For example, platelet-activating factor (PAF), a potent phospholipid inflammatory mediator, was identified in the mixed saliva of subjects with periodontal disease. Salivary PAF levels have been found to be significantly higher in untreated chronic periodontitis patients compared to controls (Garito et al. 1995). Its levels correlate with clinical indices of disease severity and extent of the disease. Furthermore, a longitudinal evaluation of the effect of periodontal therapy on salivary PAF levels in chronic adult periodontitis patients was studied and initial salivary PAF levels were found to be decreased following supragingival plaque control and further reduced following scaling and root planning (Rash et al. 1995).

Saliva contains also numerous enzymes that degrade proteins, proteoglycans, lipids and carbohydrates. Enzymes in saliva can originate from GCF, salivary glands, microorganisms, epithelial cells and polymorphonuclear leukocytes (PMNs). PMNs are an important cell type in host defense against periodontopathogenic bacteria. Their primary role of phagocytosis of microorganisms may promote local tissue destruction by the release of tissue-degrading enzymes. In fact, PMNs granules contain hydrolytic neutral enzymes, such as elestase, cathepsin B, cathepsin D, glucuronidase. Matrix metalloproteinases (MMPs), peroxidase, lysozyme, lactoferrin, and many other enzymes are also sheltered in PMNs granules. Some of these are now discussed below.

MMPs represent a neutrophil granule content, which are involved in many biological processes, including the tissue destruction in periodontitis. MMPs degrade mostly components of the extracellular matrix (ECM) and many non-ECM molecules. The major MMPs in neutrophils are MMP-8 and -9 and these are the main collagen-degrading enzymes in saliva. Since MMPs can potentially cause tissue damage, their activity is controlled by four members of the tissue inhibitor of metallo-proteinase family (TIMP). The presence of MMPs in saliva has been studied comprehensively with ELISA techniques. The levels of MMP-1, -3, -8 and -9 and their endogenous inhibitor, TIMP-1, in saliva of patients with adult periodontitis were compared to localised juvenile periodontitis and controls. Both MMP-1 and TIMP-1 were detected in all studied saliva samples, but interestingly no significant differences were detected between adult periodontitis and healthy control groups (Ingman et al. 1996).

Antioxidant activity and capacity

PMNs and macrophages produce reactive oxygen species (ROS) within their phagolysosomes and these may spill over into the tissues during phagocytosis or when they degenerate. This may cause bystander tissue damage around these cells. ROS have a great capacity to damage cells and tissues and are scavenged for within the tissues by antioxidants.

The antioxidant capacity of saliva has been investigated in healthy and chronic periodontitis patients. The major aqueous antioxidant component of whole saliva was found to be uric acid with lesser contributions from ascorbic acid and albumin. Using biochemical methods, the antioxidant capacity of the saliva was not found to be compromised in chronic periodontitis patients, and this was attributed to increased salivary flow and antioxidant flow from GCF.

Another research group investigated pheripheral (serum) and local (saliva) total antioxidant (TAO) capacities of chronic periodontitis and healthy patients using an enhanced chemiluminescent assay (Chapple et al. 1997). There were no differences in the serum TAO capacities but the salivary TAO capacities were significantly lower in the chronic periodontitis group compared with the healthy group. Thus the saliva of chronic periodontitis patients may have reduced TAO capacity, which could result from increased ROS production by inflammatory cells. The enhanced chemiluminescent assay provides a rapid simple method of measuring the total antioxidant defense in small volumes of biological fluid and hence could have diagnostic use. More work on its relationship to the progression of periodontal disease, and its capacity as biomarker needs to be done before this could be properly assessed.

Another enzymatic category, which has received the attention of periodontal researchers, is represented by enzymes released by dead cells (cytosolic enzymes). Aspartate amino transferase (AST) and lactate dehydrogenase (LHD) are soluble cytoplasmic enzymes that are confined to the cell cytoplasmic enzymes, and they can be released by dead or dying cells. Since cell death is an integral and essential component of periodontal tissue destruction, these enzymes should be released during this process and should pass with the inflammatory exudates into GCF and saliva.

While we do not have relevant studies on AST in saliva, a recent report demonstrated an increased LDH salivary activity in association with periodontal disease, specifically with the presence of calculus and pockets greater than 5mm (de La Peña et al. 2007). Clearly these markers are yet to be further investigated for their potential as salivary biomarkers for periodontitis.

Of the potential markers, PMNs-derived enzymes appear to be worthy of further study. The concentrations of host-derived elastase, chitinase and -glucuronidase are increased in patients with periodontitis and decrease following therapy (Lamster et al. 2003).

However, at the present state of knowledge, their salivary levels are not predictive of disease activity, which is the basic requirement of a diagnostic test.

 


About the author

Dr Fabiano Galassi D.D.S. M.Sc. (ACTA) Periodontology and Implant Dentistry. Practice limited to periodontology and implant dentistry. He received his Dental Degree from “La Sapienza” University of Rome. After two years general practice, he moved to Dublin where he continued working as a general practitioner until 2008.

Dr Galassi graduated with Honours from the MSc programme in Periodontology and Implant Dentistry at the Academic Center for Dentistry in Amsterdam (ACTA), in 2011. Has great interest in dental research, and he has published in peer-reviewed journals and written some chapters for periodontology textbooks.

As a member of the European Federation of Periodontology (EFP) and the Italian Federation of Periodontology (SIdP) Dr Galassi is now working at the Seapoint Clinic and Gleville Dental and his focus is on the treatment of periodontal disease, bone regeneration, cosmetic periodontal plastic surgery and implant dentistry.

 


References

Chapple, I.L., Mason, G.I., Garner, I., Matthews, J.B., Thorpe, H.G., Maxwell, S.R., & Whitehead, T.P. (1997). Enhanced chemiluminescent assay for measuring the antioxidant capacity serum, saliva, and crevicular fluid. Annals of Clinical Biochemistry 34, 412-421.

  • de La Peña, V.A., Diz Dios, P. & Tojo Sierra, R. (2007). The relationship between lactate dehydrogenase activity in saliva and oral health status. Archive of Oral Biology. 52, 911-915.
  • Fine, D.H., Markowitz, K., Furgang, D., Fairlie, K., Ferrandiz, J., Nasri, C., McKieran, M., Donnelly, R. & Gunsolley J. (2009). Macrophage inflammatory protein-1α: a salivary biomarker of bone loss in a longitudinal cohort study of children at risk for aggressive periodontal disease? Journal of Periodontology 80, 106-113.
  • Garito, M.L., Prihoda, T.J. & McManus, L.M. (1995). Salivary PAF levels correlate with the severity of periodontal inflammation. Journal of Dental Research 74, 1048–1056.
  • Hasturk, H., Kantarci, A., Goguet-Surmenian, E., Blackwood, A., Andry, C., Serhan, C.N. & Van Dyke, T.E. (2007). Resolvin E1 regulates inflammation at the cellular and tissue level and restores tissue homeostasis in vivo. Journal of Immunology  179, 7021-7029.
  • Ingman,T., Tervahartiala, T., Ding, Y., Tschesche, H., Haerian, A., Kinane, D.F., et al. (1996). Matrix metalloproteinases and their inhibitors in gingival crevicular fluid and saliva of periodontitis patients.  Journal of Clinical Periodontology 23, 1127-1132.
  • Lamster, I.B., Kaufman, E., Grbic, J.T., Winston, L.J. & Singer, R.E. (2003). Beta-glucuronidase activity in saliva: relationship to clinical periodontal parameters. Journal of Periodontology 74, 353–359.
  • Rasch, M.S., Mealey, B.L., Prihoda, T.J., Woodards, D.S. & McManus, L.M. (1995). The effect of initial periodontal therapy on salivary platelet-activating factor levels in chronic adult periodontitis. Journal of Periodontology 66, 613–623.

Patients suitable to undergo conscious sedation (CS) include those with moderate-severe anxiety, a swallow/gag reflex or a mild learning/physical disability such as cerebral palsy. Well-controlled medical conditions such as asthma, epilepsy, gastro-oesophageal reflux and mild hypertension are exacerbated by stress, making CS hugely beneficial. 1

Hospital-based intravenous (IV) CS helps patients with severe systemic disease or disability to avoid unnecessary general anaesthesia (GA). However, a small percentage of patients will still simply not tolerate dental treatment without being ‘knocked out’, making GA essential to facilitate dental treatment.

An in-depth medical, dental and social history is mandatory at a visit before treatment. It is important to ascertain the patient’s degree of dental anxiety. This helps determine the most suitable sedation technique as some patients with severe needle phobia are unable to tolerate cannulation making inhalation sedation the best option for them.2

General health considerations

ASA Physical Status Classification3

  • ASA 1 – Heathy person – suitable for IV/inhalation sedation
  • ASA 2 –Patient with mild systemic condition – mild disease with minimum functional limitation – generally suitable for IV/inhalation sedation in primary care
  • ASA 3 – Patient with severe systemic condition – significant functional limitations such as with COPD – may be suitable for inhalation sedation in primary care, but otherwise careful evaluation for hospital-based sedation
  • ASA 4 – severe systemic disease constantly threatening life – myocardial infarction or stroke <six months ago – anaesthetist-led team
  • ASA 5 – Moribund.

Age

Age is not an absolute contraindication to sedation but older patients are more sensitive
to sedatives.4 The incidence of delirium following treatment with midazolam was 10 per cent higher in the elderly.5 Elderly patients also tend to have poorly tethered, friable veins, which may be more susceptible to cannulation damage. IV sedative agents in children <12 is not recommended unless provided by a paediatric specialist. Disinhibition in adolescents is common and even slight over-sedation can lead to rapidly deteriorating respiratory depression.6

Cardiovascular System

There should be no elective surgery if the diastolic value is >110 mmHg. However, when measuring blood pressure always consider the risk of “white coat hypertension”.

Patients with controlled/uncontrolled hypertension have a more labile haemodynamic profile during CS making hypotensive swings more likely.7

It has been shown that there is little evidence that a BP < 180mmHg/110mmHg causes perioperative complications. However, a BP>180/110mmHg is linked to perioperative ischaemia, arrhythmias and cardiovascular lability. There is no clear evidence that deferring anesthesia lowers perioperative risk. The intraoperative BP should be within 20 per cent of best BP estimate.8

Dentists must evaluate pre-operatively for the presence of target organ damage such as coronary artery disease. Target organ damage lowers the treatment thresholds for raised BP.9 

A study examining the cardiovascular effects of epinephrine with IV midazolam examined 75 patients with heart disease treated in two groups.The rate-pressure product (RPP) was used to indicate myocardial ischemia. This is the systolic BP x heart rate = RPP, which is a reliable indicator of myocardial oxygen consumption. Ischemic changes were demonstrated in patients with an RPP of >12,000, increasing their CS risk. The pressure rate quotient, which is mean BP divided by heart rate, also assesses a patient’s suitability for CS. The results of this study indicated that treatment with midazolam and epinephrine does not generate significant ischemic risk. It is important that the lowest effective dose of local anaesthetic containing epinephrine is used and that intravascular injections are avoided.10

Cardiovascular system
ASA According to Blood Pressure (BP):
<140 systolic and <90 diastolicASA IPrimary care suitable
140-160/90-94mmHgASA IIPrimary care suitable
160-199/95-115mmHgASA IIISpecialist unit
200 systolic and >115 diastolicASA IVIn-patient services

NYHA classification of angina

0 Healthy
1 No hindrance to normal physical exertion
2 Slight limitation, angina with fast walking, ascending stairs, excitement
3 Significant limitation of regular movement. Angina on climbing a normal staircase
4 Angina with minimal activity/rest.

Increased stress levels exacerbate angina, making sedation and good local anaesthesia important in reducing heart rate.  Unstable angina contraindicates elective treatment. Patients with angina that affects normal daily activity such as NYHA 3 are unsuitable for sedation in primary care. If the GP/cardiologist confirms stability of angina then NYHA 2 patients can progress with elective sedation.11

Post MI

At six months post-infarctiona patient is classed as ASA 3. The risk of re-infarction is 16 per cent. Elective sedation in well-controlled patients reduces stress, helping to lower risk.

Post-percutaneous coronary intervention (PCI)

Patients must wait three months after stenting before elective sedation. Angina must always be successfully controlled before treatment.1

Classification of cardiac functional reserve capacity

  • Class 1: Able to climb a normal flight of stairs without stopping. Can continue walking with no rests – safest for IV CS
  • Class 2: Climbs without rest. Rests on top – safest for IV CS
  • Class 3: Climbs with rest during ascent – outpatient CS unsuitable
  • Class 4: Unable to climb stairs.

Patients with palpitations

Patients with benign palpitations benefit from the stress reduction produced by CS. A patient with malignant palpitations, however, must be treated in hospital. Any individual with an automated implantable cardioverter-defibrillator is unsuitable for treatment in primary care. A hospital setting is mandatory for patients with a pacemaker or those following AV node/conduction pathway ablation surgery. Wolff-Parkinson-White syndrome is an absolute contraindication to sedation.1

Respiratory disease

Midazolam has a greater effect on the respiratory system compared to the cardiovascular system. Healthy patients who present with respiratory infections on the day of treatment should be rescheduled. Careful assessment of the patient’s disease and functional reserve will indicate the most suitable setting for CS. It must be remembered that opioids act synergistically with sedation with regards to respiratory depression.12

Dyspnoea grading system12

0 Healthy
1 Mild dyspnoea
2 Moderate – limited outdoor movement – hospital management safest
3 Marked dyspnoea on minimal exertion indoors – unsuitable for outpatient sedation
4 Dyspnoea while resting – unsuitable for outpatient sedation.

Asthma

The dentist must ensure the asthmatic is well controlled. A mild asthmatic is considered ASA 2; however, an untreated Grade 2 is unsuitable for treatment in primary care. Hospital management is necessary for ASA 3 patients who have frequent episodes/attacks. It must be borne in mind that theophylline can interact unfavourably with IV midazolam. Inhalation sedation can be a safer option due to guaranteed oxygen levels.13

COPD

Extreme caution is needed with COPD patients who suffer with emphysema or bronchitis. A patient with chronic bronchitis is ASA 3. Midazolam results in dose-related respiratory depression, which is more exaggerated in COPD patients. Hospital treatment of the patient in an upright position with supplemental oxygen is required due to the increased risk of hypoxia.

If a patient needs supplemental oxygen at home or has severe orthopnoea or a productive cough then sedation is contraindicated.12

Renal system impairment

Hepatic microsomal oxidation is responsible for midazolam’s biotransformation. This is susceptible to factors such as old age, hepatic cirrhosis and drugs (cimetidine) as they reduce the oxidative capacity. A high regular intake of alcohol increases midazolam clearance.

Renal failure causes a build-up of metabolites which prolongs sedation. CS is contraindicated in cases of advanced liver disease.1

Patients undergoing haemodialysis or continuous ambulatory peritoneal dialysis are unsuitable for sedation.

Haemodialysis patients swing from being centrally underfilled where they are at risk of hypotension to centrally overfilled. Day 2 is considered the safest time to treat but outpatient CS is still best avoided. Post-renal transplant patients with good renal function may be suitable for hospital-based CS.11

Methadone and midazolam are both metabolised by the cytochrome P450 3A pathway. Chronic methadone use leads to the induction of this pathway with more rapid midazolam metabolism and higher dosage requirements.14

Neurological disease

IV midazolam helps to reduce involuntary movement in patients with multiple sclerosis and Parkinson’s disease making dental treatment more comfortable. Many patients will have reduced swallowing capacity so sitting the patient upright with adequate suction is vital. Controlled epileptics are suitable for CS although more research is needed to develop clearer guidelines. Liaising with the GP/neurologist confirms if the patient has a driving licence and when the last three seizures occurred. Anti-epileptic drugs such as phenytoin can increase or decrease plasma concentration of sedatives.11

Recovered stroke victims may experience a re-emergence of symptoms when benzodiazepines are administered. Light sedation can trigger a re-occurrence of symptoms such as right-sided paralysis and dysphasia. Sedation is contraindicated for one year after a stroke.15

Haematological disorders

Sedation should be avoided in patients with sickle cell anaemia and thalassaemia. This cohort are high risk for reduced oxygen tension with respiratory depression or over-sedation. Inhalation sedation is preferred.16

Pregnancy

The second trimester is the safest time to treat, but the mother’s metabolism is altered due to the increased demands of the baby. This makes sedation unpredictable. There are also foetal teratogenic risks.12

Intellectual or physical impairment

Patients with mild learning disabilities are suitable for sedation. Severe learning or physical difficulties require management by an anaesthetist-led team.17

Endocrine diseases

Diabetes

HbA1c helps identify pre-diabetic patients. It also helps recognise diabetics at risk of complications. A BM check of >5mmol/l pre-treatment is advisable.18

Pre-operative starvation can upset blood sugar levels. The evidence for fasting is low so a degree of clinical judgement required.19 Well-controlled diabetics are best treated in the morning to avoid interference with their insulin routine. Poorly controlled diabetics requires hospital management. Inhalation sedation can be a safer option as it is easily reversible.16

Adrenal insufficiency

Patients on long-term steroids must be treated in an anaesthetist-led facility to avoid an adrenal crisis.13

Thyroid disease

Hyperthyroidism can cause tachycardia and atrial fibrillation. Hypothyroidism can cause bradycardia, making CS unpredictable.12

Specific drug considerations

Cardiac medication: Ace inhibitors, beta blockers, calcium channel blockers and nitrates enhance the hypotensive effect of midazolam20

Erythromycin effects metabolism of midazolam21

Midazolam interacts with herbal medicine potentiating CNS depression22

Opioids such as heroin can cause significant respiratory depression with midazolam. Veins are often unusable1

Cocaine adversely effects respiratory/cardiovascular control with sedation1

Cannabis makes oxygen saturation levels unpredictable during sedation1

Central nervous system depressants for mental health conditions can act synergistically with benzodiazepines. Tolerance may have developed in these patients similar to recreational drug users.20

Assessment of vital signs

Blood pressure, oxygen saturation, BMI, heart and respiratory rate must provide a satisfactory baseline indicating fitness for sedation. Sometimes a screening may reveal an unknown condition requiring further investigation by a GP before sedation can be performed.16 It is important to predict a patient’s risk for conscious sedation. Hospital-based sedation is advisable in the following instances:

  • Baseline SaO2 is <95 per cent
  • Patients with respiratory disease such as COPD
  • Patients classified as ASA 3-4

Patients with a history of more than one attempt for previous intubation.23

BMI

A patient with a BMI of <35kg/m2 is suitable for primary care CS. Caution is advised with a BMI of 35-40kg/m2 especially if the patient has co-morbidities such as hypertension and diabetes.

The standard dental chair has an upper weight limit of 140kg making referral to hospital sometimes necessary for the use of a DIACO chair which can hold 500kg. Successful cannulation can be difficult due to the effects of increased adipose tissue on vein morphology.24

Sleep apnoea is more common in individuals with a BMI of >35. Sedation is an absolute contraindication in patients with obstructive sleep apnoea(OSA). The pharyngeal airway dilator muscles are highly sensitive to benzodiazepines.25 The STOP-BANG questionnaire is a useful screening tool for identifying potential cases of OSA.26

Malampatti system

This is a visual assessment of the distance from the base of the tongue to the soft palate. A Class 3 or 4 patient is at increased risk of airway obstruction. The patient must be asked to protrude their tongue. It is important to document the level of visibility of the back of the mouth.27

A difficult airway can also be judged if the thyromental distance is <6.5cm. A short, fat neck and receding jaw is an airway risk. Males are more susceptible to airway obstruction.28

Indications for inhalation sedation (IS)

IS can be used from the age of three. 29 Patients who are allergic to benzodiazepines or those tolerant to them due to treatment for anxiety/insomnia are suitable for IS. In patients previously addicted to benzodiazepines IV, CS can reactivate dependence making inhalation sedation safer.30

Contraindications to IS

IV sedation suits mouth-breathers, anyone taking methotrexate due to the anti-folate effects of IS and also someone who had vitreoretinal surgery within 12 weeks. Severe autism or ADHD patients are unsuitable for IS due to compliance difficulties. A hearing impediment reduces the hypnotic suggestion aspect of IS treatment making CS more effective.16

Non-titratable sedation techniques

If titratable techniques are deemed inappropriate then oral or intranasal sedation may be considered. Special care dental patients with challenging behaviour benefit greatly from these advanced techniques.31

Conclusion

A treatment plan is devised by combining the information gathered during history-taking and the clinical exam. The patient must be of sound mind to give their valid written consent at a visit separate to treatment. If needed, the presence of a responsible adult escort must be possible.32 Careful consideration regarding the nature of the patient’s disease and functional capacity is essential. The dentist has a duty of care to predict patients at risk of complications with CS such as cardiac, respiratory or neurological deterioration. After risk stratification, the optimum timing and setting for treatment must be decided to ensure patient safety.

There will always be a place in dentistry for general anaesthesia, especially for treatment plans involving extensive work on multiple teeth that make multiple sedation visits impractical and overall more expensive. Also in certain sedation cases, patients can move unpredictably, compromising the quality of the dentistry performed, which may necessitate the use of general anaesthesia.

 


References

  1. Stoelting, R.K. (2015) Pharmacology and Physiology in Anesthetic Practice. 5th edn. Philadelphia, Lippincott Williams & Wilkins.
  2. Standards for Conscious Sedation in the Provision of Dental Care; Report of the Intercollegiate Advisory Committee for Sedation in Dentistry. (IACSD). 2015.
  3. ASA http://www.asahq.org/ accessed 19/12/17.
  4. Yano H, Iishi H, Tatsuta M, Sakai N, Narahara H, Omori M. Oxygen desaturation during sedation for colonscopy in elderly patients. Hepatogastroenerology 1998 Nov-Dec; 45(24): 2138-41
  5. Weinbroum AA, Szold O, Ogorek D, Flaishon R. The midazolam-induced paradox phenomenon is reversible by flumazenil. Epidemiology, patient characteristics and review of the literature. Eur J Anaesthesiol 2001 Dec; 18(12): 789-97.
  6. Wilson KE, Thorpe RJ, Mc Cabe JF, Girdler NM. Complications Associated with IV Midazolam Sedation in Anxious Dental Patients.Primary Dental Care 2011:18(4):161-166
  7. European Society of Hypertension(ESH) and of the European Society of Cardiology(ESC).Guidelines for the management of arterial hypertension. Journal of Hypertension 2013, 31(7), 1281-1357.
  8. Fleisher LA et al. AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Non-cardiac Surgery. Journal of American College of Cardiology 2007 Volume 50, Issue 17: e242.
  9. Howell SJ, Sear JW, Foex P. Hypertension, hypertensive heart disease and perioperative cardiac risk. British Journal of Anaesth 2004 92(4): 570-83
  10. Middlehurst R, Coulthard P. The effect of midazolam sedation on indicators for myocardial ischemia. Oral Surg Oral Med Oral Pathol, Oral Radiol-Endod Oct 1999;88(4):400-5.
  11. Malamed S.F. (2010) Sedation: A Guide to Patient Management. St Louis, Mosby.
  12. Hines RL, Marschall KE. Stoelting’s Anesthesia and Co-existing disease. 7th edition Elsevier.
  13. Royal College of Surgeons of England (2013) Safe Sedation Practice for Healthcare Procedures: Standards and Guidance. London, The Academy of Medical Royal Colleges.
  14. Rab-Khan A, MacLeod D, Prichard JS. Marked increase in benzodiazepine requirements during bronchoscopy in HIV positive intravenous drug abusers. Ir Med J. 1992 Mar; 85(1): 37-8.
  15. Lazer RM, Fitzsimmons BF, Marshall RS, Mohr JP, Berman MF. Midazolam challenge re-induces neurological deficits after transient ischemic attack. Re-emergence of stroke deficits after Midazolam challenge. Stroke 2003 Mar; 34(3): 794-6.
  16. N.M. Girdler, C.M.Hill, K.E.Wilson. Conscious Sedation for Dentistry. Wiley Blackwell. Second Edition.
  17. Scottish Government(2000) Adults with Incapacity(Scotland) Act 2000. Online at: www.legislation.gov.uk (accessed Dec 15, 2017).
  18. www.diabetes.co.uk accessed 22nd Dec 2017
  19. Conscious Sedation in Dentistry. Dental Clinical Guidance. Scottish Dental Clinical Effectiveness Programme. June 2017.
  20. Tang DM, Simmons K, Friedenberg FK. Anti-hypertensive therapy and risk factors associated with hypotension during colonoscopy under conscious sedation. J Gastrointestin Liver Dis. 2012 Jun; 21(2): 165-170.
  21. Drugwise.org.uk accessed 02/01/2018.
  22. Tweddell P, Boyle C. Potential Interactions with herbal medicines and midazolam.Dental Update April 2009 Apr; 36(3): 175-8.
  23. Lazzaroni M, Bianchi-Porro G. Premedication, preparation and surveillance. Endoscopy 1999 Jan; 31(1): 2-8.
  24. WHO http://apps.who.int/bmi/index.isp?introPage=intro 3.html accessed 28/12/17.
  25. Reilly D, Boyle CA, Craig DC. Obesity and dentistry: a growing problem. Br Dental J 2009 Aug 22: 207(4):171-5.
  26. Chung F, Abdullah HR, Liao P. STOP-BANG Questionnaire: A Practical Approach to Screen for Obstructive Sleep Apnea. Anesthesiology 2008;108: 812-21.
  27. Mallampati S.R., Gatt S.P., Gugino, L.D., Desai, S.P., Waraksa, B., Freiberger, D. and Liu, P.L. A clinical sign to predict difficult tracheal intubation: a prospective study. Canadian Anaesthetists’ Society Journal 1985; 32(4). 429-434.
  28. Samsoon GLT, Young TRB(1987). Difficult tracheal intubation: a retrospective study. Anaesthesia 42: 487-490.
  29. Wilson, K.E.(2013) Overview of paediatric dental sedation: 2. Nitrous oxide/oxygen inhalation sedation. Dental Update. 40, 822-829.
  30. Blain K.M.& Hill, F.J.(1998) The use of inhalation sedation and local anaesthesia as an alternative to general anaesthesia for extractions in children. British Dental Journal, 184(12), 608-611.
  31. Manley, M.C., Ransford, N.J., Lewis, D.A., Thompson, S.A. & Forbes, M. Retrospective audit of the efficacy and safety of the combined intranasal/intravenous sedation technique for the dental treatment of adults with learning disability. British Dental Journal 2008 205(2): E3; 84-85.
  32. Johnston C&Liddle, J. The Mental Capacity Act 2005: a new framework for healthcare decision making. Journal of Medical Ethics 2007; 33(2), 94-97.

 


About the author

Dr Laura Fee graduated with an honours degree in dentistry from Trinity College, Dublin, where she was awarded the Costello medal for undergraduate research on cross-infection control procedures. She is a member of the Faculty of Dentistry at the Royal College of Surgeons. She has a Certificate in Implant Dentistry from Northumberland Institute of Oral Medicine and has been awarded the Diploma in Implant Dentistry with the Royal College of Surgeons Edinburgh.

In the first article, we explored how to establish a research question using the PICO (Population, Intervention, Comparator and Outcome) method and discussed the hierarchy of evidence. At this point in the search for evidence to support our practice, we know the question we need answered and also understand how different types of research can help to answer our questions.

We now need to think about where to find the evidence and how to assess the quality of what we find.

First let’s revisit the five steps to an evidence-based approach.

Establishing an evidence-based approach has five steps

  1. Asking answerable questions (ASK)
  2. Searching for the best evidence (AQUIRE)
  3. Critically appraising the evidence (APPRAISE)
  4. Applying the evidence (APPLY)
  5. Evaluating the outcome (ASSESS).

This article will explore points 2 and 3 of establishing an evidence-based approach to healthcare.

Question 2: Searching for the best evidence (AQUIRE)

The search for evidence

There are a number of databases that can be used to find the evidence. Which database you choose to search depends on what type of resource or evidence you require. In this section, we will introduce and explore the use of databases that host most of the information required in day-to-day practice. Three of the most commonly used databases are included in Table 1.

There are other databases available for searches of more specific topics that can be accessed through the knowledge network; for example, PsychINFO is a good database to search for psychology and behavioural science-related topics. You can see the full list of databases on offer here: www.knowledge.scot.nhs.uk

DatabaseType of evidenceKey features
PubMedSystematic Reviews, Primary ResearchAbility to create an account and save search results for later use
Cochrane LibrarySystematic ReviewsIncludes plain language summaries of reviews; useful for translating evidence for use at chair side
TRIPGuidelines, Systematic Reviews, Primary ResearchDisplays results in the style of hierarchy of evidence, reducing search time
Table 1: Commonly used evidence databases

Searching for systematic reviews and guidelines

It is always a good idea to start your search for evidence at the top of the evidence pyramid. As we discussed previously, systematic reviews and randomised control trials are the level of evidence we would require in order to think about changing our practice. At the end of our first article, we briefly discussed guidance documents. The guidance produced by SDCEP, NICE and SIGN are all evidence-based and the groups will have come to their recommendations after a thorough process.

SDCEP methods

Dr Doug Stirling is Programme Manager of the Guidance Development Group, Scottish Dental Clinical Effectiveness Programme, NHS Education for Scotland. Here he tells us more about the work of the SDCEP team and the methods they use.

Who is involved in guidance development? What is the skill mix in a guidance team?

The SDCEP team operates within NHS Education for Scotland’s Dental Directorate. Each guidance project is assigned an SDCEP project lead, who manages the project and is responsible for the methodology employed, and an administrator who helps to co-ordinate the project. For each project we also convene a Guidance Development Group comprising external individuals who are representatives of groups with a particular interest in the topic. Typically this will include various relevant branches of the dental profession and patients, and may also include other healthcare discipline relevant to the topic.

How rigorous is the process of appraising the evidence? 

Each guidance project aims to answer a number of questions. SDCEP identifies the latest evidence that is relevant to these questions, focusing on systematic reviews and other evidence-based guidelines. To assess the quality of evidence in systematic reviews, SDCEP now uses GRADE (Grading of Recommendations, Assessment, Development and Evaluation), which is a widely accepted system for grading both evidence and recommendations in clinical guidelines. More information on the GRADE system can be found at www.gradeworkinggroup.org 

We appraise guidelines using the AGREE II checklist, again an internationally recognised tool for assessing guideline quality and reliability. Find out more at www.agreetrust.org

Recommendations in SDCEP guidance result from a rigorous consideration of not only relevant research evidence, but also other factors, including, the balance of risks and benefits, patient’s views and preferences, practitioner perspectives and the practicalities.

The process SDCEP uses to develop its guidance has now been accredited by NICE (the National Institute for Health and Care Excellence), which should give users added confidence in the reliability of the guidance as an aid to their decision-making.

How does the SDCEP guidance apply to a general dental practitioner? 

The vast majority of dental care is delivered in primary care practice. Recognising this, most SDCEP guidance is primarily directed towards dentists and their teams working in general dental practice. However, the guidance is also likely to be of interest to those in training, dental educators, and secondary care and public health practitioners.

Do we always need to follow the guidance? 

Healthcare staff have the right, and indeed the duty, to make decisions that are in the best interests of their patients with their consent. SDCEP guidance is provided to inform some of these decisions. There is no obligation to follow a recommendation in the guidance if a health professional feels that it is in the best interests of an individual patient not to do so.

However, it would be advisable to document a departure from recommended practice in the patient’s clinical notes, including the reason for this.

Further information about SDCEP guidance development: www.sdcep.org.uk/how-we-work/ or to find out more about GRADE

TRIP database

Screenshot: the search function of TRIP database

TRIP (Translating Research Into Practice) is a useful resource for searching for the results of systematic reviews, randomised controlled trials and guidelines. You might think of it as a high-quality Google for health-care research. It is an online database that has a few very useful search tools. You can do a single-word search, which is similar to a Google search, but you can be more specific and use the search function established around a PICO question. Shown in Figure 1 below. The database displays results and categorises the level of evidence in a hierarchy. It is similar to the hierarchy of evidence discussed in the first article. This makes it easy to identify what type of evidence the study is before you spend time reading it.

Searching for journal articles

TRIP will also produce results from primary research but another useful database that you should understand how to use is PubMed.

PubMed is a search engine that searches the online database MEDLINE. It includes more than 27 million records. Here you will find a range of evidence. As we demonstrated in the first article, the results can be confusing at first and the searches can result in a lot of irrelevant material. We will discuss how best to use the search function later but will first look at the fundamentals of searching scientific databases.

PubMed can be accessed by typing ‘pubmed’ into any search engine or by visiting www.ncbi.nlm.nih.gov/pubmed

Free text searching and Boolean connectors

Having a systematic approach to your search will make finding relevant papers a lot easier and quicker. Most of the pointers demonstrated in this section can be broadly applied in other online searches.

You could decide to free text the search tab as you might use a search engine such as Google. This approach can often result in a large amount of unfiltered results, similar to a search for a hotel room without any information on location, standard or length of stay.

If you know the title of the exact paper you are looking for, then you could simply type this into the search box at the top of the page. You can tailor the search; for example, if you only have some of the information about a specific paper, such as the author.

A better way to search, and the best way to get the most out of the search engines, is to use Boolean search methods.

This approach still uses free text in the search but introduces AND, OR and NOT. The AND, OR and NOT are known as Boolean connectors. They all have specific functions and can help to widen or narrow your search.

Let’s use our example in article 1 to explore the Boolean connectors. Our original question was about whether or not fluoride varnish has an effect on caries rate in children. The formulation of a PICO question resulted in this:

  • Population, patient or problem: Children
  • Intervention or treatment: Fluoride varnish
  • Comparison: No treatment
  • Outcome: Caries.

Using AND

To construct a search for Pubmed we could use the following:

  • Children AND “Fluoride varnish” AND Caries

This would produce results from papers that contain all three search terms. This is a method for narrowing a search.

Phrase searching and using speech marks

You may also have noticed that the words “fluoride varnish” have speech marks either side of them. This is another useful way of narrowing a search for a specific phrase. The speech marks instruct the search engine to only include studies that have the entire phrase. If we had searched without the speech marks then we would have papers returned that include fluoride as a standalone word from varnish and not specific to our question

Using OR

Using OR can help to widen a search. For example, if we were interested in fluoride treatments other than fluoride varnish we might search the following:

  • Children AND (“Fluoride varnish” or “Fluoride mouthwash”) and Caries

This would produce results from papers that contain all our original three search terms but also include studies that look at fluoride mouthwash. Again, note the use of the speech marks to search for the entire phrase.

Truncation

Truncation is useful when you want to expand a search. An example might be in periodontics. By using the trunk of the word Periodont and then adding * to the end will return results for Periodontist, Periodontal, etc.

Controlled language searches

A more advanced way of searching the database is to use controlled language searches. MEDLINE uses Medical Subject Heading, known as MeSH. Those studying for higher level degrees may wish to use this method in their searches. Speaking to the university librarian or doing a short course would be the best way to learn more on this topic. A useful tip about PubMed is that you can register for a free account and save your searches as you go. You can also access the free online tutorials that will help you understand how to get the most out of the database.

Subscriptions/access to resources

Guidelines produced in the UK by groups such as SDCEP, SIGN and NICE are free and open access. They are readily available online. The Cochrane library is also free and open access in the UK and other countries who contribute to it, while it is also available in some developing countries. Some journal articles may be free but most will be only be available through subscription to the journal itself or via an institution of which you are a member.

All NHS employees are entitled to free registration on OpenAthens, which will give you access to The Knowledge Network that is maintained by NHS Education for Scotland. That includes general dental practitioners with an NHS contract. It is a gateway platform to accessing full text articles. If you register then you can access most articles that are returned in searches on PubMed; then you simply enter you username and password once the pay wall appears.

You can register at the address here: www.athensregistration.scot.nhs.uk

Royal College Library

If you are a member of a royal college then you have an entire library service at your disposal. Royal colleges offer members the services of a librarian who can help with literature searches and also source books that may be relevant to your search. Be sure to explore this service that is part of your membership subscription.

Specialist societies and unions

Many specialist societies have subscription services for their members. The BDA also has an extensive library and journal service for use by members which can be accessed remotely through their website.

Question 3: Critically appraising the evidence (APPRAISE)

Not every article published in a journal is a game changer. Sometimes this is easy to spot when reading an article, but other times it may be less clear as authors try to convince you about their work. Understanding the hierarchy of evidence and having some basic skills in critical appraisal will help you when trying to decide how seriously to take a new recommendation or proposed change in practice. Having critical appraisal skills can have wide-reaching benefits beyond the surgery.

At this point, we have defined our search question and found the papers we think are relevant. We know about the hierarchy of evidence, but how do we decide which ones to use? Do they all meet the same standard? Are the results valid? Do they apply to the patients I see on a day-to-day basis? Do the results include the negative outcomes of the treatment?

These questions are important to consider, how we act on the evidence will affect our patients.

Using a systematic approach to appraising the evidence in front of you is always the best way. There are a range of appraisal tools available and some are available for free download from the Centre of Evidence-based Dentistry website:  www.cebd.org

The best way to understand critical appraisal is to practice it. If you are brand new to it, then there are a number of ways you can get help to get started. This could be by attending face-to-face or online courses, reading a book or attending a journal club.

Online e-modules and tutorial videos

Terry Shaneyfelt is a teacher of evidence-based medicine; he has produced a number of YouTube videos that are useful when trying to get your head around critical appraisal. Simply search YouTube for ‘Terry Shaneyfelt’ and click on his playlists where you will see the critical appraisal section.

If you wanted to spend some time and do an online e-module then you can access one provided by the Critical Appraisal Company. There is a cost associated and the course takes six to eight hours, but it gets good reviews.

Journal clubs 

Most dentists in core or specialist training will have access to a journal club in their place of work. If there isn’t one, why not take the lead and get one started over a lunchtime once a month? There are other journal clubs that anyone can attend, such as the Edinburgh Dental Journal club that meets regularly at the Royal College of Surgeons of Edinburgh. Search for them on Facebook© to find out when the next meeting is.

Conclusion

Hopefully, after reading these first two articles you now have a basic understanding of the skills needed to practice evidence-based dentistry. We have introduced you to a range of resources that can help you to further develop your skill and knowledge. The best way to get better at using databases for searching and critical appraisal is to get on and do it. Look out for your local journal club or go online and make the most of the many free resources there are to hand.

The next and final article will focus on applying the evidence and evaluating outcomes in your practice.

 


About the authors

Portrait of Niall McGoldrickNiall McGoldrick BDS, MFDS RCPS(Glasg)

Neil is a specialty registrar in dental public health and is currently studying for his masters of dental public health at the University of Dundee. He graduated from Dundee Dental School in 2013 and then went onto complete longitudinal dental foundation training and dental core training in a range of specialities in Scotland including a placement with the SDCEP. He is a co-founder of the Scottish Charity, Let’s Talk About Mouth Cancer that is focused on the early detection of mouth cancer. He has received multiple awards for his work both inside and out of the NHS. Most recently, he received a National Award, NHS Young Achiever, from NHS Scotland and Scottish Government.

Portrait of author Derek RichardsDerek Richards BDS, FDS, MSc, DDPH,FDS(DPH)

Derek is a consultant in dental public health, editor of the Evidence-based Dentistry Journal and director of the Centre for Evidence-based Dentistry now based at the Dental Health Service Research Unit in Dundee. He holds honorary senior lectureships at Dundee and Glasgow Dental Schools and is a specialist advisor to the Scottish Dental Clinical Effectiveness Programme (SDCEP). He has been involved with a wide range of evidence-based initiatives both nationally and internationally since 1994. He is a co-author of the book, Evidence-Based Dentistry: Managing Information for Better Practice (Quintessential of Dental Practice) and the chief blogger for the Dental Elf website.

 


Bibliography

Derek Richards, Jan Clarkson, Debora Matthews, Rick Niederman. Evidence-based Dentistry: managing Information for Better Practice. London: Quintessence Publishing; 2008

Jan Clarkson, Jayne E Harrison, Amid I Ismail, Ian Needleman, Helen Worthington. Evidence Based Dentistry For Effective Practice. London: Martin Dunitz; 2003

 

 

Database Type of evidence Key feature
PubMed Systematic Reviews, Primary Research Ability to create an account and save search results for later use
Cochrane Library Systematic Reviews Includes plain language summaries of reviews; useful for translating evidence for use at chair side
TRIP Guidelines, Systematic Reviews, Primary Research Displays results in the style of the hierarchy of evidence, reducing search time

 

FIGURE 1: A screenshot of the PICO input section on TRIP. It can be accessed by typing TRIP database into any search engine or via www.tripdatabase.com 

 

A new patient in her early 30s attended for a check-up. A routine radiograph revealed caries under the amalgam filling on the upper right second premolar (UR5). When advised the tooth needed treatment, the patient revealed she had been unhappy with how it looked. The filling was very visible and shiny when she smiled. The dark appearance of the tooth also made her self-conscious. The patient had thought treatment would be long and expensive, so she hadn’t bothered to ask.

The options were to have another amalgam filling or a composite restoration. The patient was advised that further composite treatment could be needed buccally to mask any remaining grey discolouration, if she was not satisfied with the outcome. As she was concerned about the appearance of the tooth, the patient did not want an amalgam filling and decided to have the composite restoration.

 

Preparation

After a local anaesthetic was given, rubber dam was placed, with a clamp on the UR6, exposing the UR 4, 5 and 6. This was secured in place with floss ties. The old amalgam and caries were removed. The final portion of discoloured dentine was left behind as it was very deep, but the pulp was not exposed and it was still firm.

A sectional matrix band was then positioned mesially on the UR5, with a wedge and separation ring (V-ring). Initially, the enamel periphery alone was etched with 37 per cent phosphoric acid for 15 seconds. Etch was applied to the rest of the cavity for a further 15 seconds, before rinsing. A cotton pledget was used to protect the dentine during the drying process, to ensure dry enamel and moist dentine.

A two-bottle adhesive, with separate primer and adhesive, was used to complete the preparation. The dentine was primed and left for 30 seconds. The adhesive was placed on both the enamel and dentine, and allowed to sit for
30 seconds before curing.

 

Restoration

In this case, Venus Pearl composite was used. This material exhibits good levels of opacity to block out discolouration and excellent handling for posteriors, making it a very easy-to-use product.

In this restoration, a small amount of Venus Flow base liner was placed and cured. This was to mask the greyness and dark discolouration from the base of the cavity. Next a thin layer of Venus Pearl A2 shade was applied to build up the mesial wall against the matrix. The height was built up to the level of the adjacent marginal ridge. The material was then manipulated with a sharp probe at a 45 degree angle. This ensured the edge of the wall was not straight and the natural curved shape of the marginal ridge was maintained. The dentine mass was built up in increments with Venus Pearl ODC shade.

Enamel A2 shade was placed over the occlusal surfaces cusp by cusp. Complete separation of the masses was achieved by creating fissures down to the dentine layer, using a sharp probe. Secondary anatomy was manipulated into the unset material before light curing.

A mix of Venus Color ‘corn’ and ‘choco’ stains was applied to the fissures using a probe, and pressed in with a long- bristle brush. The excess was wiped away with a conventional micro-brush and the stain was cured. Highlights were placed on the ridges using Venus Color ‘white’ mixed with a little ‘corn’, to give a milky colour. Final adjustments were carried out before rough, dry polishing. The restoration was then sealed with a protective clear coating, covered with glycerine and cured.

 

Outcome

In this case, the clinical outcome was good. The tooth is regularly monitored for vitality and the patient has had no problems with it. As the caries was so deep, in the long term the tooth may require root canal treatment, but it is currently sound. The patient was delighted with the result after having endured an unsightly amalgam filling for years.

FIGURE 1: A routine X-ray revealed caries under the amalgam filling in the upper right 5

 

FIGURE 2: The UR5 filling was very visible when she smiled and the dark appearance made her self-conscious

 

FIGURE 3: The old amalgam and caries were removed following rubber dam placement

 

 

FIGURE 4: Kulzer Venus Pearl A2 shade was applied to build up the mesial wall

 


FIGURE 5: Separation of the masses was achieved by creating fissures down to the dentine layer and then stain was applied

 

FIGURE 6: The patient was delighted with the result after having endured an unsightly amalgam filling for years

 


 

About the author

Dr Monik Vasant BChD MSc is a highly experienced clinician with a special interest in minimally invasive aesthetic dentistry. He has trained under many of the world’s leading clinicians and has an MSc in aesthetic and restorative dentistry.

He is the director of Freshdental,with sites in Central London and Greater Manchester.

Monik lectures globally on minimally invasive and adhesive dentistry. His highly regarded direct composite course “Totally composite” is held throughout the UK and internationally.  He also runs a year long minimally invasive aesthetic dentistry course entitled ‘Totally Aesthetics’.

Monik is a global key opinion leader for several dental companies and has co-authored several books on various aspects of general practice.

Contact monik@freshdental.co.uk or for course information and bookings, visit www.monikvasant.co.uk

Follow Monik on Instagram @drmonik

 


 

Monik is the keynote speaker at the Scottish Dental Show 2018, to be held at Braehead Arena on 27 and 28 April. He will be presenting two lectures on Friday 27 April, ‘Composite artistry’ and ‘Composites and digital dentistry’.

To find out more and to register for your FREE delegate pass that will get you access to 140 exhibition stands and more than 50 lecture and workshops sessions, with up to NINE hours of vCPD, visit www.sdshow.co.uk

 

Top tips for practicing evidence-based dentistry: Part 3