ẢNH HƯỞNG CỦA THỜI GIAN SOI MÒN VỚI ACID PHOSPHORIC 37% LÊN ĐỘ NHÁM BỀ MẶT CỦA MEN RĂNG VĨNH VIỄN TRÊN THỰC NGHIỆM

Abstract

Objective: This study aimed to investigate the impact of etching time using 37% phosphoric acid on the surface roughness of permanent tooth enamel. We employed a 4K VHX-7000 stereoscopic microscope to assess enamel roughness through the Sa value in individuals aged from 12 to 18 years old. The research was conducted at the School of Dentistry, Hanoi Medical University in 2023. Subjects and methods: We collected 60 premolars from participants aged from 12 to 18 and divided them into four groups: Group 1 (control) - No etching, Group 2- Etching for 15 seconds, Group 3 - Etching for 25 seconds, Group 4 - Etching for 30 seconds. Using the VHX-7000 electron microscope, we measured enamel surface roughness at predetermined positions. Subsequently, we evaluated and compared the obtained Sa values. Results: Our findings revealed that enamel surface roughness (Sa) decreased as the etching time increased. Statistically significant differences were observed between the non-etching group and the 15-second, 25-second, and 30-second etching groups. However, no significant differences were found among the 15-second, 25-second, and 30-second etching groups when compared to each other. Conclusion: Increasing the enamel etching time to 15 seconds, 25 seconds, and 30 seconds led to a gradual reduction in surface roughness. Notably, after 15 seconds of etching, a discernible difference in roughness was observed compared to the initial level. However, extending the etching time to 25 seconds and 30 seconds did not yield further differences compared to the 15-second duration.