LAUSR

Objectives The aim of this study was to compare the antibacterial activity of fluoride varnishes containing different agents in children with severe early childhood caries (S-ECC). Materials and methods The study was conducted in 92 children with S-ECC. Patients who completed dental treatment under general anaesthesia were included in the study. Patients were divided randomly into four groups: 5% sodium fluoride (SF) control group ( n  = 23), 5% SF with tricalcium phosphate (TCP) ( n  = 23), 5% SF with xylitol-coated calcium and phosphate (CXP) ( n  = 23) and 5% SF with casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) ( n  = 23). Saliva mutans streptococci (MS) and lactobacilli (LB) levels were evaluated by taking saliva samples at baseline (T 0 ), 1 month (T 1 ) and 3 months (T 2 ) after treatment. Results All groups showed a significant decrease in MS and LB levels at T 1 ( P  < 0.05) except the CXP group. Only the TCP group exhibited significantly decrease MS and LB levels indicating less than 10 5  CFU at both T 1 and T 2 compared with the other groups ( P  < 0.05). Conclusion Fluoride varnish with TCP provided significantly more reduction in MS and LB levels than other fluoride varnishes. Clinical relevance Fluoride varnish with TCP had a significant antibacterial effect against cariogenic bacteria until the end of the third month. Long lasting antibacterial effect provides additional advantage for reducing bacteria levels in children. Clinical Trials registration number NCT03625310