关键词: 再矿化牙本质, 微拉伸强度, 全酸蚀, 自酸蚀, Remineralization of dentin, micro-tensile bond strength, total- etching, self-etching

Abstract: Objective The research selected totaletching and selfetching adhesives to compare their bond strength with the remineralized dentin in different etching time periods, which could provide certain theoretical instructions for a better controlling of etching time under clinical situations. Methods Collect 40 human molars of which chronic caries had reached the middle level of dentin. Get rid of decalcified dentin caused by caries lesion, and keep remineralized dentin. Section all teeth into three parts by paralleling the long axis, and then etch them with 35% Gluma etching reagent (or reagent) for 20, 40 and 60 seconds. Use totaletching and selfetching dentin adhesives respectively on dentin, and then build up the crown with resin. Cut the teeth into rectangular shape samples with a cross section of about 1 mm2 with a lowspeed saw, and observe them under a stereoscope microscope to distinguish normal dentin and remineralized dentin. Besides, bond strength was inspected with microtensile testing instrument. Results As to remineralized dentin, the microtensile bond strength in 40 s group was higher than that in the 20 s group and that in the 60 s group (P>0.05); but there was no significant difference between the 20 s group and 60 s group(P>0.05). Conclusions Etching time exerts an influence on the bond strength of remineralized dentin. There should be expanded etching time spans for remineralized dentin.