Abstract: PURPOSE: To investigate the effect of dental varnish containing fluoride either with casein phosphopeptide-amorphous calcium phosphate(CPP-ACP) or bioglass on root caries. METHODS: The active roots collected in Peking University People's Hospital from April 2017 to October 2018 were randomly divided into group A, group B, group C, and group D, each with 18 teeth. All groups received toothbrushing containing fluoride, in addition, group B received another 5% sodium fluoride, group C added 5% sodium fluoride + CPP-ACP, and group D added 5% sodium fluoride + bioglass. The severity, surface roughness and mineral concentration of root caries before and after brushing were observed. SPSS 23.0 software package was used to determine the correlation between root severity and surface roughness. RESULTS: After 50 days of brushing, the hardness of group B, C and D was significantly improved (P<; 0.05), and was significantly better than that of group A (P<; 0.05). The hardness was the highest in group D after 50 days of brushing, followed by group C and B, with significant difference(P<; 0.05). The surface roughness scores of group B and C were significantly higher than those of group A and D after 7 days of brushing(P<; 0.05). The surface roughness scores of group B were significantly higher than those of group A, C and D after 14 days of brushing(P<; 0.05). The surface roughness scores of group D were significantly higher than those of group B and C after 50 days of brushing(P<; 0.05). The severity score of root caries in group A was negatively correlated with surface roughness (P<; 0.05). The mineral concentration of each group was increased 50 days after brushing (P<; 0.05). CONCLUSIONS: Application of dental varnish containing fluoride either with CPP-ACP or bioglass can effectively prevent root caries. Compared with CPP-ACP, bioglass is more stable, and can effectively improve the mineral concentration on tooth surface.

Key words: Dental varnish containing fluoride, CPP-ACP, Bioglass, Root caries