Er,Cr:YSGG激光制洞对光固化复合树脂边缘微渗漏的影响

The effect of Er,Cr:YSGG laser irradiation on the microleakage of composite resin restorations

目的:比较在自酸蚀黏结剂的应用条件下,Er,Cr:YSGG激光制备与传统牙钻制备离体牙牙颈部洞对光固化复合树脂边缘微渗漏的影响。方法:将20个因正畸拔除的新鲜完整无龋损、无隐裂、无充填物的前磨牙随机分为两组(n=10),分别使用牙钻和Er,Cr:YSGG激光制备牙颈部洞。窝洞制备后均匀涂覆FL-BOND,用TPH复合树脂进行分层充填,打磨、抛光,37℃生理盐水中存放7 d后,进行500次温度循环实验(5±2)℃—(55±2)℃。将上述所有样本置0.5%碱性品红液中室温浸泡24 h后,沿牙体长轴通过修复体正中纵行剖开,采用染料渗入法和扫描电镜方法观察充填体微渗漏情况,运用SPSS 11.0软件包进行统计学处理。结果:牙钻制备组与激光组相比,无论牙合壁还是龈壁的染料渗入评分和边缘微缝隙宽度均无显著性差异(P>0.05)。结论:在自酸蚀黏结剂的应用条件下,Er,Cr:YSGG激光制洞不能显著减少光固化复合树脂边缘微渗漏的发生。

AIM:To compare the microleakage of Class V resin composite restorations following Er,Cr:YSGG laser and high-speed rotary preparation using a self-etch adhesive system.METHODS:Twenty orthodontically extracted human premolars were randomly divided into two groups(n=10) and Class V cavities were prepared in the teeth with Er,Cr:YSGG laser or bur.The cavities were then coated with FL-BOND adhesive system and TPH resin composite was used for restoration.After finishing and polishing,the teeth were stored for seven days in distilled water at 37 ℃ before they were subjected to thermocycling for 500 times(5±2℃-55±2℃).Then they were stained in a solution of 0.5% basic fuchsion at room temperature and sectioned in a buccolingual plane through the centre of the restorations.The marginal microleakage was observed by dye penetration method and SEM.The data was analyzed with SPSS11.0 software package.RESULTS:Microleakage test and the space between the restorations and tooth structure revealed that there were no statistical differences between bur+FL-Bond group and Er,Cr:YSGG+FL-Bond group(P>0.05).CONCLUSION:Er,Cr:YSGG laser irradiation do not reduce the microleakage of composite resin restorations significantly using a self-etch adhesive system.