Table 1_Wear resistance of three direct resin composites in artificial Saliva at varying pH levels.docx

ObjectiveTo investigate the wear resistance of three resin composites in artificial saliva at varying pH levels.
MethodsThree resin materials—Coltene BRILLIANT™NG, 3M ESPE™Filtek™P60, and Kerr Sonicfill™2—were selected and subjected to reciprocating friction tests in artificial saliva with pH values of 2, 6.8, and 8. Wear volume was measured using a three-dimensional profilometer, and statistical analysis was performed using two-way ANOVA to compare differences in material loss among the resin groups and natural tooth enamel, considering both material type and pH as factors. Surface morphology of worn samples was analyzed via SEM.
ResultsWear scar analysis revealed no statistically significant differences in wear volume among groups under pH 6.8 artificial saliva. In pH 2 artificial saliva, Group A (P60 resin) exhibited the highest wear volume, while Group B (Kerr SonicFill resin) showed the lowest wear volume, closely resembling that of natural enamel. Under pH 8 conditions, Group A again demonstrated the highest wear volume, whereas Group C (Coltene resin) exhibited the lowest. Group B (Kerr SonicFill) displayed wear volumes comparable to natural enamel (Group D). P60 resin showed significantly greater wear volume in pH 2 and pH 8 compared to pH 6.8. Kerr SonicFill resin exhibited lower wear volume in pH 2 than in pH 6.8 and pH 8, with no significant difference between pH 6.8 and pH 8. Coltene resin displayed higher wear volume in pH 2 and pH 6.8 compared to pH 8, but no significant difference was observed between pH 2 and pH 6.8. Natural enamel showed significantly greater volume loss at pH 8 compared to pH 6.8.
ConclusionUnder the tested *in vitro* conditions, Kerr SonicFill resin demonstrated wear behavior most comparable to natural enamel across varying pH environments, showing stable performance. This suggests it could be a suitable choice for dental restorations requiring durability under varying pH conditions, though direct extrapolation to clinical performance requires caution. The increased wear of natural enamel at alkaline pH was an interesting finding warranting further study.