Gingivitis is a reversible condition when gums become red, swollen and can bleed easily. Gingivitis is also very common – studies suggest that as many as 50% to 90% of adults in the UK and USA suffer from it. In susceptible people gingivitis may lead to periodontitis, which is not reversible. In periodontitis inflammation is accompanied by loss of ligaments and bone supporting the teeth. If untreated it may eventually lead to tooth loss. Severe periodontitis is the sixth most widespread disease globally.
It is recognised that maintaining a high standard of oral hygiene is important for the prevention and treatment of gingivitis. Toothbrushing is the main method for maintaining good oral hygiene. Other cleaning methods commonly used include dental floss, interdental brushes and scaling and polishing carried out by a dental professional. Some people have difficulty controlling plaque build-up and preventing gingivitis using only conventional tooth cleaning. Therefore people sometimes use mouthrinses containing chlorhexidine in addition to conventional tooth cleaning. These mouthrinses are readily available over the counter; prescriptions generally not being required outside the USA.
What was the research?
A systematic review to examine whether the use of chlorhexidine mouthrinse (a broad spectrum antiseptic) in addition to other conventional tooth cleaning helps to control and improve gingivitis (inflammation of the gums). Does the frequency of rinsing or the concentration of the solution affect the result and are there any undesirable side effects?
Who conducted the research?
The research was conducted by a team led by Patrice James from Cork University Dental School, Ireland, on behalf of Cochrane Oral Health. Helen V. Worthington, Carmel Parnell, Mairead Harding, Thomas Lamont, Andrea Chung, Helen Whelton and Philip Riley were also on the team.
What evidence was included in the review?
51 randomised controlled trials were selected for inclusion in this review. They analysed a total of 5345 participants, the evidence in this review is up to date as of 28 September 2016. Generally study participants were children and adults who had gingivitis or periodontitis, were able to use usual tooth cleaning methods and were healthy. We did not exclude studies where some or all participants had medical conditions or special care needs as we considered the use of mouthrinses with chlorhexidine to be particularly relevant to them. The included studies assessed the effects of chlorhexidine mouthrinse used for at least 4 weeks in addition to conventional tooth cleaning on gingivitis in children and adults.
What did the evidence say?
There is high-quality evidence that the use of mouthrinses containing chlorhexidine in addition to usual toothbrushing and cleaning for 4 to 6 weeks or 6 months leads to a large reduction in the build-up of plaque. There is also high-quality evidence of a moderate reduction in gingivitis in people with a mild level of it, although because the level of disease was already low this is not considered clinically important. The nature of the available evidence does not allow us to determine the level of reduction of gingivitis in people with moderate to severe levels of it.
There was no evidence that one concentration or strength of chlorhexidine rinse was more effective than another.
Rinsing for 4 weeks or longer causes tooth staining, which requires scaling and polishing carried out by a dental professional. Other side effects have been reported, including build-up of calculus (tartar), temporary taste disturbance and temporary shedding of/damage to the lining of the mouth.
How good was the evidence?
One study was assessed as being at unclear risk of bias, with the remaining 50 being at high risk of bias, however this did not affect the quality assessments for gingivitis and plaque as we believe that further research is very unlikely to change our confidence in the estimate of effect.
What are the implications for dentists and the general public?
Chlorhexidine mouthrinse is indicated in particular clinical situations for short periods of time. Using chlorhexidine mouthrinse for longer periods of time in individuals with special care needs who cannot maintain an adequate level of plaque control using mechanical cleaning methods alone must be carefully weighed against the adverse effects associated with its use.
What should researchers look at in the future?
Further well-conducted randomised controlled trials are needed to investigate the effect size for adjunctive chlorhexidine mouthrinse use in individuals with moderate or severe levels of gingival inflammation, as the majority of the studies included in the main analysis of the Gingival Index at 4 to 6 weeks and 6 months involved healthy participants with low levels of gingivitis.
James P, Worthington HV, Parnell C, Harding M, Lamont T, Cheung A, Whelton H, Riley P. Chlorhexidine mouthrinse as an adjunctive treatment for gingival health. Cochrane Database of Systematic Reviews 2017, Issue 3. Art. No.: CD008676. DOI: 10.1002/14651858.CD008676.pub2.
This post is an extended version of the review’s plain language summary, compiled by Anne Littlewood at the Cochrane Oral Health Editorial Base.