漂白剂对牙釉质和树脂黏结强度的影响

Effect of tooth bleaching agents on the shear bond strength of enamel to composite resin

目的:比较漂白后不同时间黏结操作时,釉质与复合树脂黏结后的剪切强度,评价漂白对黏结的影响。方法:18颗人磨牙切取釉质共36片,按照随机数字表法随机分为4组。1组:漂白2周+即刻黏结;2组:漂白2周+延迟7d黏结;3组:漂白2周+延迟14d黏结;4组:生理盐水2周+即刻黏结。万能材料试验机测量剪切强度。结果:对照组为(24.4±3.7)MPa,漂白后即刻黏结,釉质剪切强度为(14.2±2.5)MPa,与漂白前有明显差异(P=0.000,95%CI7.6344～12.8478)。7d后剪切强度有所恢复,为(19.0±2.0)MPa,但与漂白前仍有差异(P=0.000,95%CI2.8322～8.0456),约14d后,剪切强度可恢复至漂白前水平,为(21.9±2.5)MPa(P=0.056,95%CI-7.0031～5.1434)。结论:漂白后即刻黏结,牙齿与树脂的黏结强度会降低。延迟黏结时间2周,黏结强度可以恢复。

AIM:To compare the shear bond strength of enamel to composite resin in different post treatment time periods after tooth bleaching. METHODS: Thirty six enamel specimens obtained from 18 human molars were randomly divided into 4 Groups (n=9): group 1 (adhesion immediately after bleaching); group 2 (adhesion at the 7th day after bleaching); group 3(adhesion at the 15th day after bleaching); group 4 (adhesion without bleaching).The former three were bleached for 1 weeks, and the later one was infused with normal saline for 2 weeks. RESULTS: The shear bond strength of the group 1 was (14.2± 2.5) MPa, significantly lower than that of the control group [(24.4± 3.7) MPa](P=0.000, 95% CI, 7.6344- 12.8478).While the strength of the group 2 recovered to (19.0± 2.0) MPa, there was also a significant difference from that of the control group( P=0.000, 95% CI, 2.8322- 8.0456) . After 14 days the shear strength was (21.9± 2.5) MPa, which was close to that of the control group ( P=0.056, 95% CI, - 7.0031- 5.1434) .