常用粘结剂与桩核材料的不同搭配使用微渗漏发生率及程度的比较

Contrast study of microleakage incidence and extent of collocation uses of several clinical and frequently used cements and dowel materials

目的:评价不同核材料修复后的牙齿经铸造金属全冠修复后边缘微渗漏的发生率及程度,为临床选择合理的粘接材料、桩核材料及其配伍提供依据。方法:将90颗大小相似的完好磨牙随机分为9个实验组,分别为银汞核树脂粘接组、银汞核聚羧酸粘接组、银汞核玻璃离子粘接组、铸造核树脂粘接组、铸造核聚羧酸粘接组、铸造核玻璃离子粘接组、树脂核树脂粘接组、树脂核聚羧酸粘接组和树脂核玻璃离子粘接组。对离体牙进行铸造金属全冠及固定尺寸的Ⅱ类洞牙体预备后,分别用3种不同的核材料(树脂、银汞、铸造合金)充填窝洞。常规方法铸冠,用3种不同的粘结材料(聚羧酸ZP、玻璃离子CX、树脂C&B)进行粘固。经温度循环、染色、包埋后,片切标本,镜下观察冠边缘及核下微漏情况。结果:树脂粘接组三种核材料核-牙界面微漏程度差异无统计学意义,聚羧酸及玻璃离子粘接组、银汞核与树脂核下微漏指标小于铸造核(P<0.05),树脂粘结组冠边缘微漏程度小于聚羧酸锌和玻璃离子粘结组(P<0.05)。结论:树脂粘接剂抗微漏性能优于玻璃离子与聚羧酸锌粘结剂;树脂核在预先对粘结面处理后,其抗微漏性能与银汞核近似,优于铸造合金核。

Objective To evaluate the microleakage degree of complete cast-metal crowns cemented onto teeth that were rebuilt with different core materials and provide some evidences for clinical application.Methods Ninety extracted molar teeth were randomly divided into nine groups as follows： amalgam / super bond CB,amalgam/ zinc polycarboxylate,amalgam/ glass-ionomer CX,gold/ super bond CB,gold/ zinc polycarboxylate,gold/ glass-ionomer CX,composite/ super bond CB,composite/ zinc polycarboxylate,composite/ glass-ionomer CX.Tooth preparations for complete veneer cast crowns were completed.A classⅡcavity preparation with fixed dimension was made in each tooth.Three different core materials（composite resin,amalgam,cast-gold） were filled in them.The artificial crowns were cast and cemented onto teeth by using three different cements（composite resin super bond CB,glass ionomer CX,zinc polycarboxylate）.The specimens were thermocycled and dyed.They were then embedded in epoxy resin and sectioned.The degree of microleakage was evaluated and scored.Results In super bond CB group,the three different cores showed no significant difference in core base microleakage.In zinc polycarboxylate group and glass-ionomer CX group,the core base microleakage in amalgam and composite were significantly different from those in gold（P0.05）.The crown microleakage degree of composite resin was lower than those of glass ionomer and zinc polycarboxylate（P0.05）.Conclusion The microleakage degree of composite resin is less than those of glass ionomer and zinc polycarboxylate,and the microleakage of amalgam and composite resin is also lower than that of cast-gold core materials.