Can government-supported preventive fluoride varnish application service reduce pulp-involved primary molars?

Objectives Fluoride varnishes are reported to reduce 37-43% of dental caries; however, it remains unclear whether they can prevent severe decay. The study investigated the association between the government-supported preventive fluoride varnish application service (FVAS) and the risk of undergoing treatments of pulp-involved primary molars. Methods Children who were younger than 6 years and did not receive any dental treatment between the first and last services within 2 years were defined as the "preventive-FVAS group." After the matching process, 45,296 children were selected for further analysis until the end of 2013. The log-rank test and Cox proportional hazard models were employed to estimate the effects of preventive-FVAS on the treatments of pulp-involved primary molars, including pulpectomy and early extraction before the age of 8 years. Results After adjusting for confounding factors, adjusted hazard ratios for the treatments of pulp-involved primary molars for children who received preventive-FVAS were 0.96 (95% CI = 0.92-1.00) for initiation of pulpectomy, 0.93 (95% CI = 0.86-1.00) for completion of pulpectomy, and 0.87 (95% CI = 0.82-0.92, P < 0.0001) for early extraction, especially for those who received three or more FVAS. Conclusions Although preventive-FVASs were associated with a 4-13% decreased risk of undergoing treatments of pulp-involved primary molars within a lower risk subset, we suggest the implementation the current Taiwan government-supported FVAS program needs to be modified. Further studies are warranted to evaluate whether it would be a better strategy if the program focused only on the high-risk group.