自酸蚀偶联剂不同作用时间对托槽与牙面剪切粘接强度影响的研究

Effects of priming time of self-etching primer on shear bond strength of orthodontic brackets

目的测量自酸蚀偶联剂不同作用时间下托槽与牙面间剪切粘接强度,以探讨正畸临床上运用自酸蚀偶联剂粘接托槽的最佳作用时间.方法选择48颗正畸减数的恒双尖牙,随机分为四组,自酸蚀偶联剂作用时间分别为:5秒、15秒、30秒和60秒.所有样本均用光固化粘接剂粘接托槽.半小时后测量四组的剪切粘接强度(Shear bond strength,SBS)及粘接剂残留指数(Adhesive remnant index,ARI),并通过扫描电子显微镜观察树脂-牙釉质界面形态学改变.结果四组托槽与牙面平均剪切粘接强度范围5.1609 Mpa～5.5146 Mpa,组间剪切粘接强度无显著性差异(p＞0.05);ARI评分表明:自酸蚀偶联剂作用时间为60秒时,牙面上残留的粘接剂明显多于其他三组;电镜观察结果显示:随着自酸蚀偶联剂作用时间的延长,树脂突的形态更规则,结构更致密.结论自酸蚀偶联剂作用时间在5～60秒范围内较厂家推荐时间延长或缩短均不会影响其剪切粘接强度.

Objective To investigate the effect of different priming time on the shear bond strength （SBS） of orthodontic brackets promoted by a new self-etching primer system. Methods Fourty-eight healthy premolars were randomly divided into four equal groups according to four different priming time： 5 seconds, 15 seconds, 30 seconds, and 60 seconds. Stainless steel brackets were bonded in each test group with a light-cured composite resin （Transbond^XT 3M）. The shear bond strength and the adhesive remnant index （ARI） were determined in the first 30 minutes after bonding. Scanning electron microscopic （SEM） observation was also performed to examine the effect of priming time on the morphology of the resin-enamel interface. Results The shear bond strength ranged from 5. 1609 MPa to 5. 5146 MPa, and no statistically significant difference was detected among the four groups; There was more residual adhesive remained on the teeth when the priming lime was extended to 60 seconds. SEM observation revealed that a more uniform appearanle resin tags were formed when the priming time was extended. Conclusions The priming time within 5-60 seconds had no apparent effect on the shear bond stength of orthodontic brackets when using the new self-etching primer system.