Use of fluoride varnish with functionalized tricalcium phosphate for prevention of early childhood caries: A randomised clinical trial

The aim of this study is to compare the caries-preventive effect of 5% sodium fluoride (NaF) varnish with and without functionalized tricalcium phosphate (fTCP) on young children with untreated active caries. This 24-month, double-blind, parallel-designed, randomised controlled trial recruited 408 three-year-old children with untreated active carious lesion. Dental caries was diagnosed at the cavitation level according to WHO criteria, with carious lesions categorized as active if gentle probing revealed softness. A tooth surface was scored as sound in the absence of treated or untreated clinical dental caries. Recruited children were block-randomized into two intervention groups based on caries status (dmfs=1–3 or >3). Group A received semi-annual application of a NaF varnish on all tooth surfaces. Group B received semi-annual application of a NaF varnish with fTCP on all tooth surfaces. Silver nitrate was applied on carious tooth surface before varnish application to promote caries arrest. Per protocol analysis was performed. At the 24-month evaluation, 356 children (87%) and 29,628 tooth surfaces (87%) were assessed. No significant difference was found in the attrition rate between groups (p = 0.30). At child level, no significant difference was found in the incidence rate of dental caries (86% vs. 82%, p = 0.38), the increment of mean dmft score (2.7 vs. 2.5, p = 0.50) and mean dmfs scores (4.8 vs. 4.3, p = 0.37) between groups. At tooth surface level, Group A had more sound tooth-surface becoming carious (865 vs. 742; 5.7% vs. 5.1%; p = 0.035). However, results of the generalized estimating equation model indicated treatment protocols were not significant related to the incidence of carious surfaces (p = 0.197) after adjusting clustering effect and confounding factors. When applied semi-annually to children with active caries, the 5% NaF varnish with fTCP and the conventional NaF varnish showed equivalent preventive efficacy in children with active caries.