两种自酸蚀处理剂处理牙本质和牙釉质的电镜观察

SEM Evaluation of Etching Effects of Two Self-etching Primers on Enamel and Dentin

目的 比较两种自酸蚀处理剂Non RinseConditioner(NRC)和ClearfilSEBondprimer(SE)处理牙本质及釉质的超微结构差异 ,及延长处理时间对黏结面脱矿的影响。方法 18颗人的第三磨牙切取牙釉质 (未经打磨 )及牙本质各 18片 ,分别随机分成 6组。 1组 :NRC处理 2 0s ;2组 :NRC处理 2 0s后水冲洗 ;3组 :NRC处理 6 0s后水冲洗 ;4组 :SE处理 2 0s;5组 :SE处理 2 0s后水冲洗 ;6组 :SE处理 6 0s后水冲洗。扫描电镜观察。结果 SE处理牙釉质及牙本质脱矿效果均较NRC弱。SE处理牙本质未经水冲洗组可见较厚的玷污层残留。NRC处理后未经水冲洗组可见较薄的玷污层残余。两者处理时间延长均可加强脱矿效果。用于釉质时 ,NRC处理相同时间 ,水冲洗组脱矿效果弱于未经水冲洗组。结论 SE侵蚀性弱于NRC ,提示近髓角区可优先选择SE。经吹干、未完全挥发的NRC可持续作用 。

Objective To compare with the effects of two self etching primers with Non Rinse Conditioner (NRC) and Clearfil SE Bond primer (SE) on the micromorphology of tooth enamel and dentin.Methods Unground enamel specimens obtained from 18 extracted third molars were randomly classified into six groups ( n =3), and treated as follows: Group 1:NRC/20*!s; Group 2:NRC/20*!s+rinsing; Group 3:NRC/60*!s+rinsing; Group 4:SE/20*!s; Group 5:SE/20*!s+rinsing; Group 6:SE/60*!s+rinsing. Same treatments were applied to flatened dentin specimens (six groups, n =3). All the treated surfaces were examined by SEM.Results Compared with NRC, less enamel and dentin demineralization caused by SE was observed. SEM examination revealed a thin smear layer within the surface dentin conditioned by NRC without rinsing, while specimens conditioned by SE without rinsing provided thick smear layers. More demineralization might be obtained with prolonged conditioning time. With the same application time spent on enamel, the rinsing with water appeared less effective.Conclusion NRC was more aggressive than SE, which could only partly dissolve smear layer. It was suggested that SE was preferred to be used in the region close to the pulp. NRC remains which were not volatilized might continue after air blowing. So it was recommended to apply adhesives right after NRC conditioning.