In Vitro Effect of Strontium-Doped ۴۵S۵ Bioglass and Nd:YAG Laser on Microhardness of Demineralized Enamel

Background: This study aimed to assess the effect of strontium-doped ۴۵S۵ bioglass (BG) and Nd:YAGlaser on the microhardness of demineralized enamel.Materials and Methods: In this in vitro, experimental study, ۶۵ sound enamel samples were preparedof human premolars and polished, and then immersed in a demineralizing solution for ۱۰ weeks. Thesamples were randomly divided into ۵ groups of control, BG, laser, laser plus BG, and BG plus laser.Two samples of each group underwent assessment of surface morphology under a scanning electronmicroscope. Finally, the microhardness of samples was measured using a Vickers hardness tester, and datawere analyzed by ANOVA.Results: The mean microhardness of the BG group was significantly higher than that of other groups(P < ۰.۰۵). The lowest microhardness was noted in the control group. The difference in microhardnesswas significant between laser and laser plus BG groups (P < ۰.۰۵). Further, the BG plus laser group hada significant difference in microhardness with BG and control groups (P < ۰.۰۵). The difference betweenlaser plus BG and control groups was also significant in this respect (P < ۰.۰۵). Eventually, maximummorphological changes were observed in the BG group.Conclusions: Overall, BG seems to be effective for the treatment of incipient enamel caries. It effectivelyincreases enamel microhardness and decreases mineral loss while preserving the integrity of the enamel surface.

Keywords:

Bioactive glass , Laser , Enamel , Microhardness , Caries