银汞粘结对牙尖无基釉抗折的影响——体外实验

Effect of Amalgam bondign to cusp enamel reinforcement vitro test

目的 确定Scotch -bondMP粘结剂对增加银汞充填后牙尖无基釉抗折力的作用。方法 取健康新鲜离体、牙体的近远中径及颊舌径一致、牙尖高度相等的双尖牙 2 0颗。磨除近远中邻面 ,使之近远中径为 4mm ,在颊牙尖釉质层下制备 4mm× 4mm× 3mm的洞型并随机分成两组。实验组在洞璧上涂一层粘结剂 ,自然固化 6 0秒后填入调拌好的银汞合金 ,对照组仅填入银汞合金。 37℃生理盐水中保存 1周 ,在Instron测试机上测定使牙尖折裂的力。结果 实验组和对照组的力值分别为 775 .7± 5 5 1.7和 5 89.7± 30 2 .0 (牛顿 ) ,但统计学检验无显著性差异。结论 Scotch

Objective Determining cusp enamel reinforcement of Scotch bond MP to bonded amalgam teeth. Methods 20 fresh extracted,same size in mesiodistal and height of cusp,1st up premolars were taken for this study.The tooth preparations were enamel wall of test cavities were treated with Scotch bond,then amalgam was condensed,the others were filled with amalgam only.After one week store in 37 ℃ NaCl solution,the breaking strenth were measured with an Instron. Results Mean force for fracture of test and control groups was 775.7 N and 589.7 N separately analysis showed that deviation of means had no statistical significance( P > 0.05 ). Conclusion Reinforcement of cusp statistical nobase enamel with amalgam by Scotch bond was limited.