Inhibition of dental caries around composite resin containing ursolic acid

Abstract

Inhibition of dental caries around composite resin containing ursolic acidYu-Kyoung Won, D.D.S.Department of Dental Science, Graduate School, Yonsei University(Directed by Prof. Chan-Young Lee, D.D.S., M.S., Ph.D.)1. ObjectiveRecurrent caries formation around existing restorations represents the primary reason for replacement of composite resin restorations. Use of the antimicrobial restorative material to inhibit the bacterial biofilm formation can be one way to prevent the recurrent caries around restoration. The aim of this study is to compare the degree of caries-like lesion formation around experimental composite containing different concentrations of ursolic acid.2. Materials and methodsFour different concentrations of ursolic acid (0, 0.1, 0.2, 0.5 wt%) were added to Filtek Z350 (3M ESPE, St Paul, MN, U.S.A.). Standard cavities (2mm x 3.5mm x 2mm) were prepared on the buccal and lingual surfaces of twelve extracted human molars and restored with these composite resins (n=6) containing antibacterial substances. Caries-like lesions were produced on the experimental teeth using S. mutans-induced artificial caries system. Specimens were incubated in a mixture of saliva and medium containing 1% carbohydrate at 37℃ for 5 days. Demineralization of dental enamel around the margins of restorations were analyzed with quantitative light-induced fluorescence(QLF). The demineralized specimens were photographed with QLF-D BiluminatorTM 2 (Inspektor Research Systems bv, Amsterdam, Netherlands) and the fluorescence images of white spot area 1mm around the restorations were analyzed using image analysis software QA2 (Inspektor Research Systems bv, Amsterdam, Netherlands).3. ResultsAfter 5 days of incubation, all the specimens showed the production of white spot lesions. For QLF analysis results, the total loss of fluorescence radiance of dental enamel around the margins of restorations was significantly less in the 0.5% ursolic acid-containing composite group compared with 0.1% ursolic acid-containing composite group and control group (p<0.05). 4. ConclusionFollowing the limitation of this experiment, composite resin containing 0.5% ursolic acid might inhibit the secondary caries induced by S. mutans around restoration.