不同表面处理方法对非龋性硬化牙本质超微结构的影响

EFFECTS OF DIFFERENT SURFACE TREATMENT METHODS ON ULTRASTRUCTURE OF NON-CARIOUS SCLEROTIC DENTINE

目的:探讨两种牙体预备方法对非龋性硬化牙本质超微结构的影响。方法:20颗咬合面有典型硬化牙本质的磨牙随机分为四组:A组用高速涡轮牙钻预备,B组用牙钻预备后35%磷酸酸蚀15s,C组用Er,Cr:YSGG激光预备,D组用激光预备后35%磷酸酸蚀15s。扫描电镜观察各组磨牙硬化牙本质表面的超微结构。结果:A组硬化牙本质表面较平整,有玷污层;B组酸蚀后硬化牙本质表面变得粗糙,玷污层被去除,可见硬化结晶柱突出于牙本质小管口。C组硬化牙本质表面粗糙,管间牙本质有蜂窝状改变,牙本质小管突出;D组酸蚀后牙本质小管开口增大,有硬化结晶柱突出。结论:使用Er,Cr:YSGG激光预备非龋性硬化牙本质能明显改善其表面形态,结合35%磷酸酸蚀可获得更佳的粘接表面。

Objective： To investigate the effects of different tooth preparation methods on ultrastructure of non-carious sclerotic dentine. Methods： 20 molar teeth with typical sclerotic dentin on the occlusal surface were randomly divided into 4 groups： Teeth in group A were prepared with high-speed turbine dental drill; Teeth in group B were prepared by dental drill and 35% phosphoric acid for 15s; Teeth in group C were prepared by Er, Cr：YSGG laser; Teeth in group D were prepared by laser and 35% phosphoric acid for 15s. Scanning electron microscope was used to observe the ultrastmcture of the sclerotic dentin surface. Results： Group A： the sclerotic dentin surface was relatively fiat, and covered by smear layer. Group B： the sclerotic dentin sttrface became rough, the smear layer had been removed and sclerotic column protruded from dentinal tubules. Group C： the sclerotic dentin surface was rough, the intertubular dentin were honeycombing changed, and the dentinal tubules protruded. Group D： the opening of dentinal tubules increased and sclerotic column protruded. Conclusions： Prepare the dentin surface by Er, Cr.YSCJG laser can obviously improve the non-carious sclerotic dentine surface, combined 35% phosphoric acid etching at the same time can obtain a better bonding surface.