EFFECT OF 6-MONTHLY APPLICATIONS OF CHLORHEXIDINE VARNISH ON INCIDENCE OF OCCLUSAL CARIES IN PERMANENT MOLARS - A 3-YEAR STUDY

Objectives: The aim of this study was to assess the effect of a chlorh exidine varnish on occlusal caries incidence when applied 6-monthly in to the fissures of erupting and freshly erupted permanent molars. Meth ods: In a double-blind clinical trial, 332 children aged 5/6 and 11/12 . years attending a Child Dental Health Centre were randomly assigned to a control and an experimental group. Criteria For inclusion in the study were that all first permanent molars in 5-6-year-olds and all se cond permanent molars in 11-12-year-olds either had recently erupted, or were in a stage of eruption, or would erupt within half a year. At baseline, counts of dmfs/DMFS and mutans streptococci in saliva were r ecorded. During a maximum of 3 years, every 6 months the occlusal surf aces of molars in the experimental group received a 40% chlorhexidine varnish application, whereas those in the control group received a pla cebo varnish application. Results: Data of 316 children were analysed and ANOVA showed no significant occlusal caries reduction in this samp le of Dutch 5/6- and 11/12-year-old children. After stratification int o low and high caries risk groups, a statistically significant caries- reducing effect on occlusal caries in permanent molars was found in th e group of children with greater than or equal to 10(6) mutans strepto cocci per mi saliva (P<0.05). Conclusion: Six-monthly application of c hlorhexidine varnish has no caries-reducing effect on occlusal caries in recently erupted permanent molars in a population with low caries p revalence. (C) 1998 Elsevier Science Ltd. All rights reserved.