나노 및 마이크로 수산화인회석 함유 구강양치액의 재광화 효과 비교

Abstract

Objectives: The aims of this study were to compare the remineralizing effect of hydroxyapatite depending on the particle size and to evaluate the combined effects of nano-HAp and fluoride on an early caries lesion in human enamel. Methods: Forty-eight specimens with average VHN of 25-45 were selected from the demineralized enamel and assigned to 8 groups. The treatment solutions consisted of experimental and remineralizing solution and specimens were incubated in a simple infusion model. The treatment solutions consisted of 0%, 1%, 5%, and 10% nano-HAp in distilled water or the same concentrations in a 0.05% NaF solution. In order to verify the remineralizing effect on the microhardness of enamel, each specimen was immersed into the treatment and the remineralizing solution for 12 hours each(total 24 hours) and the VHN was evaluated. This step was repeated making a total of 48 hours. Transmission and scanning electron microscope were used to identify the change in the enamel surface. Statistical significance was identified by one-way ANOVA followed by a Duncan's studentized range test using the Window SPSS 12.0 statistical package program. Results: The degree of remineralization according to the VHN values was higher in the NaF groups than in the distilled water groups. The remineralizing effect increased with increasing treatment and remineralizing time. In addition, the VHNs of the demineralized enamel increased with increasing HAp concentration. The remineralizing effect was more observed in nano-HAp than micro-HAp(P<0.05). SEM showed that the microstructure of the enamel surface was changed by NaF and nano-HAp. In particular, the enamel surfaces in the nano-HAp groups showed filling of the micro pore structure. Conclusion: Nano-HAp has more remineralizing effect than micro-HAp. In addition, HAp appears to have a synergistic remineralizing effect with the fluoride.