Dental caries is the most prevalent chronic disease. It affects 60-90% of school-aged children and a majority of adults. Approximately 2.4 billion people have untreated decay in permanent teeth. Fluoride mouthrinses have been used for 5 decades for caries prevention in children and a number of reviews of its effectiveness have been conducted including an earlier version of this review published in 2003.

The primary aim of this updated Cochrane Review was to determine the effectiveness and safety of fluoride mouthrinses in preventing dental caries in the child and adolescent population.

Methods

Searches were conducted in the Cochrane Oral Health’s Trials Register,the Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase, CINAHL, LILACS (Latin American and Caribbean Health Science Information Database, BBO (Bibliografia Brasileira de Odontologia; Proquest Dissertations and Theses, Web of Science Conference Proceedings US National Institutes of Health Trials Register (http://clinicaltrials.gov) and the World Health Organization International Clinical Trials Registry Platform.

At least two reviewers screen studies for inclusion abstracted data from studies and assessed risk of bias. The primary measure of effect was the prevented fraction (PF), the difference in mean caries increments between treatment and control groups expressed as a percentage of the mean increment in the control group. Random-effects meta-analyses were conducted where data could be pooled. Potential sources of heterogeneity were explored in random- effects meta-regression analyses.

Results

• 37 trials involving 15,813 children and adolescents were included.
• 28 studies were at high risk of bias and 7 were at unclear risk of bias.
• All of the studies tested supervised mouthrinse use in schools with 2 also including home use.
• Sodium Fluoride rinse on a daily or fortnightly bases basis and at two main strengths, 230 or 900 ppm F, respectively was most commonly used.
• 35 trials (15,305 participants) contributed data on permanent tooth surface for meta-analysis, the D(M)FS pooled PF =27% (95%CI; 23% – 30%; I² = 42%) (moderate quality evidence).
• Meta-regression found no significant association between estimates of D(M)FS prevented fractions and baseline caries severity, background exposure to fluorides, rinsing frequency or fluoride concentration
• There was no relationship between prevented fraction and study precision (no evidence of reporting bias).
• The pooled estimate of D(M)FT PF = 23% (95% CI, 18% to 29%; I² = 54%), from the 13 trials (moderate quality evidence).
• There was limited information concerning possible adverse effects or acceptability of the treatment regimen in the included trials.
• Three trials incompletely reported data on tooth staining, and one trial incompletely reported information on mucosal irritation/allergic reaction.
• None of the trials reported on acute adverse symptoms during treatment.

Conclusions

The authors concluded:-

This review found that supervised regular use of fluoride mouthrinse by children and adolescents is associated with a large reduction in caries increment in permanent teeth. We are moderately certain of the size of the effect. Most of the evidence evaluated use of fluoride mouthrinse supervised in a school setting, but the findings may be applicable to children in other settings with supervised or unsupervised rinsing, although the size of the caries-preventive effect is less clear. Any future research on fluoride mouthrinses should focus on head-to-head comparisons between different fluoride rinse features or fluoride rinses against other preventive strategies, and should evaluate adverse effects and acceptability.

Comments

The use of fluoride has been an important element of caries prevention for many years and mouthwash is an effective delivery system. This updated Cochrane review provides a detailed updating of the 2003 review, which showed clear evidence of a caries-inhibiting effect of fluoride mouthrinse in the permanent teeth of children. This update includes just one new trial so the overall result is the same, in that the average caries reduction in terms of decayed, missing and filled tooth surfaces (DMFS) in permanent teeth of about 27% (95%CI 23-30%).   One important issue raised in the discussion is that the body of this evidence is from studies conducted in the 1960s and 1970s when exposure to fluoridated toothpaste was not as widely available as it is today. This is an area considered by the authors and addressed in the meta-regression analysis, which looked at, initial level of caries severity, background exposure to fluoride and fluoride concentration and frequency of use, although no clear relationship was demonstrated. However they do suggest the evidence is applicable to current practice as.

the eight trials from the 1980s and 1990s show no evidence of smaller treatment effects.

Links

Primary paper

Marinho VCC, Chong LY, Worthington HV, Walsh T. Fluoride mouthrinses for preventing dental caries in children and adolescents. Cochrane Database of Systematic Reviews 2016, Issue 7. Art. No.: CD002284. DOI: 10.1002/14651858.CD002284.pub2.