Cochrane reviews of randomized trials of fluoride therapies for preventing dental caries.

AIM: To present the evidence summarized in the Cochrane fluoride reviews.

STUDY DESIGN: An overview of the results of selected systematic reviews.

METHODS: Relevant systematic reviews published in the Cochrane Database of Systematic Reviews (CDSR) were identified by searching 'The Cochrane Library issue 4, 2008', using the terms 'Fluoride' and 'Caries'. Complete Cochrane reviews assessing the effectiveness of any fluoride-based intervention for preventing caries were selected, and their main features and findings were reviewed.

RESULTS: 14 papers were identified of which 11 were relevant full-text reviews. The results were assessed of 7 reviews published from 2002 to 2004 concerning the relative effectiveness of 4 topical fluoride treatments (toothpastes, gels, varnishes and mouthrinses) in preventing caries in children and adolescents. Comparisons in these reviews were made against non-fluoride controls, against each other, and against different combinations. Findings from 4 reviews published between 2004 and 2006, assessing other fluoride modalities (slow release devices, milk), specific comparison/site (fluoride varnishes versus sealants in occlusal surfaces), and particular population and caries outcome (fluorides for white spot lesions in orthodontic patients) were also assessed. The 7 reviews confirm a clear and similar effectiveness of topical fluoride toothpastes, mouthrinses, gels and varnishes for preventing caries, and show that additional caries reduction can be expected when another topical fluoride is combined with fluoride toothpaste. Evidence is insufficient to confirm the effectiveness of slow release fluoride devices and fluoridated milk. The comparative effectiveness of other modes of delivering fluoride, such as to orthodontic patients is also as yet unclear. Fissure sealants appear more effective than fluoride varnish for preventing occlusal caries but the size of the difference is unclear.

CONCLUSIONS: The benefits of topical fluorides are firmly established based on a sizeable body of evidence from randomized controlled trials. The size of the reductions in caries increment in both the permanent and the primary dentitions emphasizes the importance of including topical fluoride delivered through toothpastes, rinses, gels or varnishes in any caries preventive program. However, trials to discern potential adverse effects are required, and data on acceptability. Better quality research is needed to reach clearer conclusions on the effects of slow release fluoride devices, milk fluoridation, sealants in comparison with fluoride varnishes, and of different modes of delivering fluoride to orthodontic patients.