Dental anxiety commonly presents a barrier for patients in achieving oral health. The Scottish Health Survey 2009 found that 20 per cent of women and 11 per cent of men surveyed were ‘very nervous’ about visiting the dentist1. Clearly, this barrier of anxiety and phobia must be addressed in order that access to high-quality care is an achievable goal for all.
Numerous techniques are available to the dental profession to assist patients in accessing and accepting dental treatment they require. Non-pharmacological behaviour management techniques such as acclimatisation, desensitisation and positive reinforcement are essential in treating patients with dental anxiety. However, for a significant proportion of patients, non-pharmacological techniques will require to be supplemented with conscious sedation in order that treatment can be carried out with a minimum level of stress.
The General Dental Council defines conscious sedation as: “A technique in which the use of a drug or drugs produces a state of depression of the central nervous system enabling treatment to be carried out, but during which verbal contact with the patient is maintained throughout the period of sedation. The drugs and techniques used to provide conscious sedation for dental treatment should carry a margin of safety wide enough to render unintended loss of consciousness unlikely. The level of sedation must be such that the patient remains conscious, retains protective reflexes, and is able to understand and to respond to verbal commands.” 2
The Scottish Dental Clinical Effectiveness Programme guidance on ‘Conscious Sedation in Dentistry’ gives the following indications for the use of conscious sedation techniques:
- Dental anxiety and phobia
- Prolonged or traumatic dental procedures
- Medical conditions potentially aggravated by stress
- Medical conditions affecting the patients ability to co-operate
- Special needs3.
With an ageing population and an increasing demand for advanced and complex treatment plans, a diverse range of people, including both adult and child patients, will require a form of dental sedation at some point in their lifetime.
A number of methods are available for the delivery of pharmacological agents that will induce a state of sedation in patients including intravenous midazolam, oral midazolam and relative analgesia (RA) using nitrous oxide. These methods all have an important place in a general practice; however, a further method of delivery of midazolam through an intranasal atomiser could prove an invaluable form of sedation, particularly for children and adults with a needle phobia.
Delivering midazolam through the nose is a simple and convenient method, as access is easy, delivery is painless and the risk of a needlestick injury to the sedationist is avoided. The olfactory mucosa is in direct contact with the brain and CSF allowing the medication absorbed to directly enter the brain.
This method avoids ‘first pass metabolism’ by the portal circulation and, as such, the administered drug is not subject to destruction by hepatic enzymes. Overall, this allows for a bioavailability of between 55-100 per cent. Midazolam should be delivered in a low-volume and high-concentration solution, as large volumes are likely to be unpleasant for the patient.
Atomisation of the drug results in a higher bioavailability than either spray or drops. The broad 30-micron spray is designed to ensure excellent mucosal coverage and the highest bioavailability possible. Mucosal Atomisation Devices (MAD) (fig 1) are single use, disposable and can fit onto a standard syringe. In an atomised form, midazolam has a bioavailability of up to 85 per cent, with a clinical onset of action of around five to 10 minutes. About 40 minutes of useful sedation are available for clinical procedures to be carried out.
Intranasal midazolam has been studied extensively, with hundreds of studies published regarding its effectiveness in sedation, particularly in relation to paediatric patients. It is also highly valuable in the treatment of acute seizures and status epilepticus.
A study by Wood in Society for the Advancement of Anaesthesia in Dentistry Digest aimed to determine whether a combination of intranasal midazolam and RA sedation was a ’practical alternative’ to general anaesthesia. A clinical audit of 100 cases on paediatric patients aged three to 13 years who had been referred for GA were treated with a combination of intra-nasal midazolam and RA.
The study found that 96 per cent of the required dental treatment was successfully completed using this technique. No clinically relevant oxygen desaturation occurred during the procedures and the study concluded that in selected cases, this technique provides a safe alternative to general anaesthesia 5.
A study in the Australian Dental Journal 2012 by Özen et al aimed to evaluate the outcomes of moderate sedation alone or combined with different dosages and administration routes of midazolam in unco-operative paediatric patents. The study examined 240 children and randomly allocated them to one of four groups where midazolam was administered intra-nasally, orally or sedation was achieved with nitrous oxide only.
The highest success rate (87 per cent) was found in the group who received 0.2mg/kg intra-nasally. The authors were able to conclude that the evidence indicates a sufficient basis to justify the use of this technique in primary care “as part of the spectrum of anxiety and behaviour management for this group”.
At Clyde Dental Practice, we have used the intra-nasal route to sedate adult needle-phobic patients and also to manage dental anxiety in children. All patients referred to the practice attend for an initial sedation assessment appointment at which a full medical history is taken, including baseline oxygen saturation, and heart rate and blood pressure are recorded.
Dental history, including reasons for dental anxiety, is noted. Options for sedation are discussed with the patient and with children and their parents/guardian. Written consent for both sedation and treatment is signed and scanned into the practice computer system.
Where intra-nasal sedation is being used, the patient’s weight is recorded and used to calculate the dose of midazolam required, for example, a child of 40kg at 0.2mg/kg, 8mg of midazolam, giving a volume of 0.2ml of a solution of 40mg/1ml (fig 2). This high concentration/low volume results in greater bioavailability. Volumes over 1ml result in run off out of the nostril, lower bioavailability and poor patient experience.
Intra-nasal midazolam is given in conjunction with inhalation sedation of nitrous oxide and oxygen. Following administration of intra-nasal anaesthesia, it is not uncommon for children to cough and cry. Parents are advised in advance to expect this. Despite the low volume of drug being given, some of this can run into the patient’s oropharynx and it can taste unpleasant. Combining midazolam with lignocaine helps minimise any discomfort from intra nasal administration.
Onset of action takes approximately 10 minutes. Oxygen saturation and heart rate are monitored throughout treatment until discharge from recovery. Duration of sedation is between 30-45 minutes, allowing most routine treatment to be undertaken on child patients. The degree of sedation can be variable, particularly in child patients, and restlessness is more common than with adult IV sedation. Intra-nasal midazolam results in retrograde amnesia, helping patients to forget or have little memory of their treatment.
The combination of intra-nasal midazolam with inhalation sedation is considered to be an advanced form of sedation by SAAD and should be restricted to those with postgraduate training in sedation. At Clyde Dental, a sedationist separate from the operating dentist is used. As with other forms of sedation, intra-nasal is not a replacement for general anaesthesia. Patients must be willing to co-operate and accept the need for dental treatment. Intra-nasal sedation provides another option to help manage anxious patients.
In summary, the use of intra-nasal midazolam is clearly shown in the literature to be a highly effective method of sedation. However, it is essential that practitioners using this advanced technique undertake an adequate level of training. Cases should be carefully selected in order to achieve a high level of success with this technique. Sedation should be used in conjunction with effective communication and non-pharmacological behaviour management techniques.
About the author
Clive graduated from Glasgow University in 1993 and is currently a partner at Clyde Dental Practice, Ivy Cottage Dental Practice and Commonwealth Dental Practice. He has been very active in post-graduate education, having achieved the following qualifications: DGDP(UK) 1996, MGDS(Glas) 1999, FFGDP(UK) 2002, Diploma in Conscious Sedation (Newcastle) 2004, Diploma in Implant Dentistry RCS 2007 and Fellowship in Dental Surgery (RCS Ed) 2011.
He is a visiting GDP supervising undergraduates in the restorative department at Glasgow Dental School, teaches on the Scottish Dental Implant Year Course and lectures on CBCT in dental practice. He was previously a diploma tutor for the West of Scotland MFDGP(UK)/MJDF study group and remains involved with the FGDP(UK).
His practices welcome patient referrals for restorative and oral surgery under conscious sedation (intravenous and inhalation). Clive accepts referrals for implant dentistry including bone grafting and sinus augmentation.
1. ‘The Scottish Health Survey 2009 – Dental Health’ http://www.scotland.gov.uk/Publications/2010/09/23154223/24. Accessed 28/10/2012.
2. General Dental Council. Maintaining Standards. Guidance to dentists on professional and personal conduct. Published 1997, modifed 1998.
3. SDCEP ‘Conscious Sedation in Dentistry – Dental Clinical Guidance.’ May 2006.
5. The safety and efficacy of intranasal midazolam sedation combined with inhalation sedation with nitrous oxide and oxygen in paediatric dental patients as an alternative to general anaesthesia – M Wood (http://www.ncbi.nlm.nih.gov/pubmed/20151606). Accessed 29/10/12.
6. Outcomes of moderate sedation in paediatric dental patients (http://www.ncbi.nlm.nih.gov/pubmed/22624753). Accessed 29/10/12.