Frequently asked questions on the new research
1. What are the main conclusions from LISTERINE®’s new research?
The peer reviewed clinical studies published this year in the American ‘Journal of Dental Hygiene’ (2022), demonstrated that LISTERINE®, when added to brushing and flossing reduces interproximal plaque by 28.4% when compared to brushing and flossing alone*1.
Additionally, Listerine was shown to achieve a 4.6x greater interproximal plaque reduction above the gumline versus flossing that was performed by a dental hygienist**2.
2. What was the methodology of the new research?
Johnson & Johnson Consumer Health conducted two studies with 350+ subjects that were randomised, controlled, examiner-blind, parallel group clinical studies with supervision provided by a dental professional at an American Dental Association-qualified site.
Milleman and colleagues evaluated the efficacy of various oral hygiene regimens in the prevention and reduction of plaque above the gumline. 213 subjects were examined for oral soft tissue tolerance and Modified Turesky Plaque Index (TPI) at baseline. After a dental prophylaxis, subjects were randomly assigned to one of the following treatment regimens to use throughout the study:
1. Brush only (control),
2. Brush + rinse,
3. Brush + floss, or
4. Brush + floss + rinse
LISTERINE® Cool Mint® Mouthwash, Reach® Unflavoured Waxed Dental Floss, and Colgate® Cavity Protection Toothpaste were used in this study. Flossing instructions were given, and subjects demonstrated competency. Product use was supervised through video phone calls once daily on weekdays, with the second daily and weekend product uses unsupervised. Subjects were examined at 4 and 12 weeks. Bosma and colleagues evaluated the efficacy of rinsing with LISTERINE® and brushing versus dental flossing and brushing in the prevention and reduction of plaque above the gumline under once-daily supervision.
Examinations included oral soft tissue assessment and Modified Turesky Plaque Index (TPI), at baseline, at week 4 and week 12. This 12-week study randomised 156 subjects into four groups: brushing plus LISTERINE® Cool Mint® under supervision, brushing and flossing under supervision, brushing and flossing by a hygienist, and brushing plus hydroalcohol (5%) mouthwash under supervision. All subjects were supervised once daily, Monday to Friday at the clinic. Second oral hygiene instances on weekdays, and twice daily oral hygiene instances on weekends at home were unsupervised and recorded in diaries.
3. Who conducted the research?
Johnson & Johnson Consumer Health placed both these studies with Salus Research, Inc. in Fort Wayne, Indiana, US, which is an internationally known clinical research team specialising in the independent evaluation of oral health care products. Both studies were subsequently peer reviewed and published in the American ‘Journal of Dental Hygiene’.
4. What does this mean for my patients?
It is widely accepted that the bacteria present in dental plaque are a major cause of caries and periodontal disease, and that prevention of these conditions requires removal of that plaque.
Whilst the standard recommendation is to brush the teeth and clean interdentally, evidence suggests that the adjunctive use of a mouthwash may provide benefits beyond mechanical cleaning alone.
For patients who brush and floss, adding LISTERINE® reduces interproximal plaque by 28.4% vs brushing and flossing alone.*1 For patients who don’t floss, LISTERINE® is shown to reduce interproximal plaque above the gumline by 4.6x vs floss.**2
*Sustained plaque reduction above the gumline with continual twice daily use for 12 weeks after a dental cleaning. Flossing underwent once daily supervision on weekdays. Use LISTERINE® as part of a 3-step routine.
**Sustained plaque reduction above the gumline with continual twice daily use for 12 weeks after a dental cleaning. Flossing was performed by a dental hygienist.
1. Milleman J, et al. Comparative effectiveness of toothbrushing, flossing and mouthrinse regimens on plaque and gingivitis: a 12-week virtually supervised clinical trial. Journal of Dental Hygiene 2022; 96(3): 21-34
2. Bosma ML, et al. Efficacy of flossing and mouth rinsing regimens on plaque and gingivitis: a randomised clinical trial. Journal of Dental Hygiene 2022; 96(3): 8-20