NIHR DC Discover

NIHR Signal Regular use of fluoride mouthrinse is an option to reduce tooth decay in school children

Published on 8 November 2016

doi: 10.3310/signal-000327

A reduction in tooth decay of about 27% can be expected from the supervised regular use of fluoride mouthrinsing by school children.

Tooth decay has a significant impact on health and wellbeing. It is more common in disadvantaged communities and can be prevented by good oral hygiene and diet with reduced sugar intake. Children and young people are encouraged to brush their teeth regularly with fluoride toothpaste and some schools in the UK have supervised programmes to encourage this.

This review included 37 trials where children received supervised mouthrinsing in schools, but did not compare this with supervised toothbrushing.

Current guidance recommends daily use of mouthrinses for children aged eight and over with dental health concerns. These findings suggest there may be a role for extending use as an option to children who don’t already brush their teeth.

Local authority commissioners and practitioners might consider where mouthrinsing sits in current childhood oral health promotion initiatives. Many of these trials were published 30 or more years ago when dental decay was more common.

The place of this school intervention alongside other ways of getting fluoride to the tooth surface will depend on local circumstances and particularly what other ways children might be receiving fluoride.

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Why was this study needed?

Tooth decay is the most common chronic condition in children and young people. A third of all children starting school each year have signs of tooth decay and in 1973, this figure was more than nine in ten. Nevertheless tooth extractions are the biggest reason children are admitted to hospital for general anaesthetics in the UK and rates are increasing.

Tooth decay can have many effects including pain and potential school absence, withdrawal from social activities and tooth extraction. Tooth decay tends to be more common in deprived areas and is an important issue in addressing health inequalities.

Decay happens when mouth bacteria break down dietary sugars producing acids which erode the tooth enamel. Fluoride has been shown to prevent this process. Fluoride mouthrinses are commonly used by adults and are sometimes promoted for older children, as part of a package of interventions including regular tooth brushing, flossing and advice on sugar intake. It is important to understand the best advice to offer for schools, parents and local authority commissioners of oral public health.

This Cochrane review is an update of a 2003 review, and is part of a series of reviews looking at different fluoride interventions to prevent tooth decay.

What did this study do?

This updated review found one new trial in addition to 36 identified in 2003. Trials examined supervised mouthrinsing in schools in 15,813 children aged five to 14 years. Most trials compared a fluoride mouthrinse to a placebo, the remaining five compared with no treatment. Trials assessing mouthrinsing against other fluoride applications were excluded.

Trials were of at least one year’s duration, though the fluoride concentration and frequency of mouthrinsing varied, from almost daily to only a few times a year. The main outcome explored was the rate of tooth decay.

Many trials dated from the 1970s and 1980s. The lack of a clear explanation on aspects such as how participants were allocated to the randomised groups means that we can only be moderately confident in the results. Amongst the 37 trials included, thirteen trials were conducted in the USA, with its different health system, and four in the UK.

What did it find?

  • Fluoride mouthrinse reduced tooth decay by 27% on average (95% confidence interval [CI] 23% to 30%), as measured by a reduction in the number of decayed, missing, and filled tooth surfaces. This was from pooled analysis of 35 trials in permanent tooth surfaces, which had broadly consistent findings.
  • Looking at permanent teeth, fluoride mouthrinse significantly reduced the number of decayed, missing, and filled teeth (rather than surfaces) by 23% (95% CI 0.18 to 0.29). This was from pooled analysis of 13 trials, also with broadly consistent findings.
  • Variables such as baseline dental health, fluoride concentration, rinsing frequency, or exposure to fluoride toothpaste or fluoridated water had no apparent influence on the results.
  • There was limited data on other outcomes, including adverse effects.

What does current guidance say on this issue?

NICE public health guidance suggests that local authorities and health and wellbeing commissioning partners or head teachers consider supervised tooth brushing scheme for primary schools in high risk areas  and if resources are limited, prioritise reception and year one (up to age seven).

Public Health England recommends that fluoride mouthrinses containing at least 1,350ppm fluoride are prescribed for children aged eight years and above if they have tooth decay or their dentist has other cause for concern (for example, if they have a brace). Mouthrinses should be used daily, in addition to twice daily brushing with toothpaste. It is emphasised that mouthrinsing is carried out at a different time from toothbrushing to avoid washing away the protection of the fluoride-containing toothpaste.

What are the implications?

The regular use of fluoride mouthrinses by children could be an important factor in preventing tooth decay for those that cannot brush their teeth. Though these studies did not compare mouthrinses to other fluoride treatments, there may be a case for commissioners and public health practitioners to consider mouthrinsing as one part of good oral hygiene for children.

Schools may play an important role in helping to develop healthy habits as all trials involved supervised mouthrinsing. It is unclear whether children may be motivated to continue by themselves. The lack of safety information and the fact that many trials dated from 30 or more years ago and quality may further limits the interpretation of these findings.

Citation and Funding

Marinho VCC, Chong LY, Worthington HV, et al. Fluoride mouthrinses for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2016;(7):CD002284. 

This review was supported by the NIHR, via Cochrane Infrastructure funding to Cochrane Oral Health.

Why was this study needed?

Tooth decay is the most common chronic condition in children and young people. A third of all children starting school each year have signs of tooth decay and in 1973, this figure was more than nine in ten. Nevertheless tooth extractions are the biggest reason children are admitted to hospital for general anaesthetics in the UK and rates are increasing.

Tooth decay can have many effects including pain and potential school absence, withdrawal from social activities and tooth extraction. Tooth decay tends to be more common in deprived areas and is an important issue in addressing health inequalities.

Decay happens when mouth bacteria break down dietary sugars producing acids which erode the tooth enamel. Fluoride has been shown to prevent this process. Fluoride mouthrinses are commonly used by adults and are sometimes promoted for older children, as part of a package of interventions including regular tooth brushing, flossing and advice on sugar intake. It is important to understand the best advice to offer for schools, parents and local authority commissioners of oral public health.

This Cochrane review is an update of a 2003 review, and is part of a series of reviews looking at different fluoride interventions to prevent tooth decay.

What did this study do?

This updated review found one new trial in addition to 36 identified in 2003. Trials examined supervised mouthrinsing in schools in 15,813 children aged five to 14 years. Most trials compared a fluoride mouthrinse to a placebo, the remaining five compared with no treatment. Trials assessing mouthrinsing against other fluoride applications were excluded.

Trials were of at least one year’s duration, though the fluoride concentration and frequency of mouthrinsing varied, from almost daily to only a few times a year. The main outcome explored was the rate of tooth decay.

Many trials dated from the 1970s and 1980s. The lack of a clear explanation on aspects such as how participants were allocated to the randomised groups means that we can only be moderately confident in the results. Amongst the 37 trials included, thirteen trials were conducted in the USA, with its different health system, and four in the UK.

What did it find?

  • Fluoride mouthrinse reduced tooth decay by 27% on average (95% confidence interval [CI] 23% to 30%), as measured by a reduction in the number of decayed, missing, and filled tooth surfaces. This was from pooled analysis of 35 trials in permanent tooth surfaces, which had broadly consistent findings.
  • Looking at permanent teeth, fluoride mouthrinse significantly reduced the number of decayed, missing, and filled teeth (rather than surfaces) by 23% (95% CI 0.18 to 0.29). This was from pooled analysis of 13 trials, also with broadly consistent findings.
  • Variables such as baseline dental health, fluoride concentration, rinsing frequency, or exposure to fluoride toothpaste or fluoridated water had no apparent influence on the results.
  • There was limited data on other outcomes, including adverse effects.

What does current guidance say on this issue?

NICE public health guidance suggests that local authorities and health and wellbeing commissioning partners or head teachers consider supervised tooth brushing scheme for primary schools in high risk areas  and if resources are limited, prioritise reception and year one (up to age seven).

Public Health England recommends that fluoride mouthrinses containing at least 1,350ppm fluoride are prescribed for children aged eight years and above if they have tooth decay or their dentist has other cause for concern (for example, if they have a brace). Mouthrinses should be used daily, in addition to twice daily brushing with toothpaste. It is emphasised that mouthrinsing is carried out at a different time from toothbrushing to avoid washing away the protection of the fluoride-containing toothpaste.

What are the implications?

The regular use of fluoride mouthrinses by children could be an important factor in preventing tooth decay for those that cannot brush their teeth. Though these studies did not compare mouthrinses to other fluoride treatments, there may be a case for commissioners and public health practitioners to consider mouthrinsing as one part of good oral hygiene for children.

Schools may play an important role in helping to develop healthy habits as all trials involved supervised mouthrinsing. It is unclear whether children may be motivated to continue by themselves. The lack of safety information and the fact that many trials dated from 30 or more years ago and quality may further limits the interpretation of these findings.

Citation and Funding

Marinho VCC, Chong LY, Worthington HV, et al. Fluoride mouthrinses for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2016;(7):CD002284. 

This review was supported by the NIHR, via Cochrane Infrastructure funding to Cochrane Oral Health.

Fluoride mouthrinses for preventing dental caries in children and adolescents

Published on 30 July 2016

Marinho, V. C.,Chong, L. Y.,Worthington, H. V.,Walsh, T.

Cochrane Database Syst Rev Volume 7 , 2016

BACKGROUND: Fluoride mouthrinses have been used extensively as a caries-preventive intervention in school-based programmes and by individuals at home. This is an update of the Cochrane review of fluoride mouthrinses for preventing dental caries in children and adolescents that was first published in 2003. OBJECTIVES: The primary objective is to determine the effectiveness and safety of fluoride mouthrinses in preventing dental caries in the child and adolescent population.The secondary objective is to examine whether the effect of fluoride rinses is influenced by:* initial level of caries severity;* background exposure to fluoride in water (or salt), toothpastes or reported fluoride sources other than the study option(s); or* fluoride concentration (ppm F) or frequency of use (times per year). SEARCH METHODS: We searched the following electronic databases: Cochrane Oral Health's Trials Register (whole database, to 22 April 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 3), MEDLINE Ovid (1946 to 22 April 2016), Embase Ovid (1980 to 22 April 2016), CINAHL EBSCO (the Cumulative Index to Nursing and Allied Health Literature, 1937 to 22 April 2016), LILACS BIREME (Latin American and Caribbean Health Science Information Database, 1982 to 22 April 2016), BBO BIREME (Bibliografia Brasileira de Odontologia; from 1986 to 22 April 2016), Proquest Dissertations and Theses (1861 to 22 April 2016) and Web of Science Conference Proceedings (1990 to 22 April 2016). We undertook a search for ongoing trials on the US National Institutes of Health Trials Register (http://clinicaltrials.gov) and the World Health Organization International Clinical Trials Registry Platform. We placed no restrictions on language or date of publication when searching electronic databases. We also searched reference lists of articles and contacted selected authors and manufacturers. SELECTION CRITERIA: Randomised or quasi-randomised controlled trials where blind outcome assessment was stated or indicated, comparing fluoride mouthrinse with placebo or no treatment in children up to 16 years of age. Study duration had to be at least one year. The main outcome was caries increment measured by the change in decayed, missing and filled tooth surfaces in permanent teeth (D(M)FS). DATA COLLECTION AND ANALYSIS: At least two review authors independently performed study selection, data extraction and risk of bias assessment. We contacted study authors for additional information when required. The primary measure of effect was the prevented fraction (PF), that is, the difference in mean caries increments between treatment and control groups expressed as a percentage of the mean increment in the control group. We conducted random-effects meta-analyses where data could be pooled. We examined potential sources of heterogeneity in random-effects metaregression analyses. We collected adverse effects information from the included trials. MAIN RESULTS: In this review, we included 37 trials involving 15,813 children and adolescents. All trials tested supervised use of fluoride mouthrinse in schools, with two studies also including home use. Almost all children received a fluoride rinse formulated with sodium fluoride (NaF), mostly on either a daily or weekly/fortnightly basis and at two main strengths, 230 or 900 ppm F, respectively. Most studies (28) were at high risk of bias, and nine were at unclear risk of bias.From the 35 trials (15,305 participants) that contributed data on permanent tooth surface for meta-analysis, the D(M)FS pooled PF was 27% (95% confidence interval (CI), 23% to 30%; I2 = 42%) (moderate quality evidence). We 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 in metaregression analyses. A funnel plot of the 35 studies in the D(M)FS PF meta-analysis indicated no relationship between prevented fraction and study precision (no evidence of reporting bias). The pooled estimate of D(M)FT PF was 23% (95% CI, 18% to 29%; I(2) = 54%), from the 13 trials that contributed data for the permanent teeth meta-analysis (moderate quality evidence).We found 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. AUTHORS' CONCLUSIONS: 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.

Most trials involved mouthrinses containing sodium fluoride at a concentration from 100 to 3,000 parts per million (ppm), or 0.02% to 0.66%. Public Health England recommends mouthrinses containing 0.05% sodium fluoride – at least 1,350 ppm.

Toothpaste containing between 1,350 and 1,500 ppm of fluoride is thought to be most effective. Children under three years of age are advised to brush twice daily use a smear of toothpaste containing at least 1,000 ppm of fluoride; children aged three to six years, a pea-sized amount. Above this age the recommendation is as for adults, using toothpaste with a concentration of 1,350 to 1,500 ppm.

All children aged three and over, or younger if there is concern, are also advised to have a varnish containing 2.2% sodium fluoride applied to teeth two or more times a year.

Expert commentary

School-based fluoride rinsing programmes have long been used in North America. This review confirms that fluoride mouthwashes are effective in preventing dental caries when used in such schemes. However, in the UK, school-based tooth brushing schemes are preferred as a means of increasing exposure to fluoride in at-risk children. While there may be merit in comparing mouthrinses with other community based preventive strategies as the authors suggest, rinsing lacks the secondary socialisation aspects of tooth brushing schemes, in encouraging good oral hygiene practices in children who may not otherwise be exposed to regular tooth brushing.

Ivor G Chestnutt, Professor and Hon Consultant in Dental Public Health, Cardiff University