EDTA预处理硬化牙本质对树脂粘结强度的影响

目的：采用微拉伸试验比较EDTA（Ethylene Diamine Tetraacetie Acid,乙二胺四乙酸）预处理硬化牙本质前后的离体牙树脂粘结强度。方法：选择24颗具有典型楔状缺损的离体牙,12颗离体牙的楔状缺损处为Ⅲ级以上硬化牙本质,其余12颗为正常牙本质。以平分楔状缺损为标准对离体牙进行纵剖,随机分为硬化牙本质对照组A与实验组B;正常牙本质对照组C与实验组D。实验组均使用EDTA（Glyde File Prep EDTA）预处理牙本质表面,再行自酸蚀树脂粘结。测定4组样本的微拉伸粘结强度。结果：微拉伸实验显示测得A、B、C、D,4组样本的微拉伸强度分别为（9.49±2.23）MPa、（10.50±2.16）MPa、（10.89±4.76）MPa、（10.99±5.21）MPa。实验组B的粘结强度显著高于对照组A,有统计学意义（P〈0.05）;而实验组D的粘结强度略高于对照组C,但无统计学意义。结论：利用EDTA预处理能提高硬化牙本质的自酸蚀树脂粘结强度,但对正常牙本质无明显作用。

Effect of EDTA Pretreatment on Bond Strength of the Adhesives to Sclerotic Dentin

Objective:To evaluate the micro-tensile bond strength(μTBS)of adhesives to sclerotic dentin in non-carious cervical lesions pretreated with EDTA(Ethylene Diamine Tetraacetie Acid).Methods:The anterior teeth and premolars with non-carious typical cervical lesions which extracted for periodontitis were collected.The cervical lesions of 12 teeth were sound dentin,and the other 12 were of scale Ⅲ sclerotic dentin.All the teeth were cut into two parts longitudinal to the cervical lesions and then were randomized into 4groups respectively:Group A(control group of sclerotic dentin),Group B(test group of sclerotic dentin),Group C(control group of sound dentin)and Group D(test group of sound dentin).The surfaces of cervical lesions in Group B and D were pretreated by EDTA.Then the cervical lesions were resin-restored with a self-etching adhesive.μTBS of four groups were measured.Rusults:μTBS of group A,B,C,D was 9.49±2.23Mpa,0.50±2.16Mpa,0.89±4.76Mpa and 10.99 ±5.21Mpa.The mean bond strength of group B was significantly higher than group A.There were no statistics differences between group C and D.Conclusion:The bond strength of sclerotic dentin is effectively enhanced by pretreated with EDTA before self-etching adhesive,but it doesn’t work in sound dentin.