Effects of fluoride‐ and chlorhexidine‐containing varnishes on plaque composition and on demineralization of dentinal grooves in situ

Abstract

The aim of the study was to compare the effects of Cervitec, containing 1% chlorhexidine (CHX) and 1% thymol, Fluor Protector, containing 0.1% fluoride, their 1:1 mixture, and a placebo varnish on the percentage of mutans streptococci and lactobacilli in plaque and on the underlying dentin demineralization, as assessed by microradiography. Bovine dentine discs, fitted with three parallel grooves, received one of the varnish treatments into the first groove and on the adjacent part of the dentin surface. Volunteers (n=23) wore the discs fixed to their partial dentures for four consecutive 3 wk periods. Microbiological analysis of plaque accumulated in the grooves showed no difference between groups. Fluoride varnishes (Fluor Protector and mixed varnish) had a significantly larger inhibitory effect on mineral loss in the treated groove than Cervitec or placebo. All treatment varnishes had more pronounced effect in panelists (n=14) with higher degree of demineralization (mineral loss in placebo group ≥1,200 vol%×μm). In these panelists, CHX‐containing varnishes showed an inhibitory effect on demineralization in all grooves, also in the two non‐varnished grooves. As fluoride varnishes had the largest localized effect on demineralization, and CHX varnishes were showing a peripheral effect, a combined treatment could be the preferred method to obtain an optimal caries preventive effect in caries‐prone individuals.