脉冲Nd:YAG激光对复合树脂与牙体硬组织密合度的影响

Effect of pulse Nd:YAG laser on the adaptation of resin to dental hard tissue

目的 :探讨脉冲 Nd:YAG激光对复合树脂与牙体硬组织之间密合度的影响 ,为临床上解决微渗漏提供参考依据。方法 :收集离体的人前磨牙 60个 ,随机分成 6组。分别选择牙合壁和龈壁作为观察对象 ,按分组分别对洞壁进行表面处理 ,复合树脂充填 ,观察染料的渗入情况。结果 :牙合壁 6个组中 ,不处理组的微渗漏百分数 ( MP)显著高于其它 5组 ( P<0 .0 5 ) ,激光 +酸蚀组的 MP显著低于激光组、酸蚀 +激光组及不处理组( P<0 .0 5 ) ;其余 4组间无显著差异 ( P>0 .0 5 )。龈壁 6个组中 ,无论釉牙骨质界上或下 ,激光组、1 0 -3液组和酸蚀组之间均亦无显著性差异 ( P>0 .0 5 )。对比观察中 ,牙合壁的密合度优于龈壁 ;釉牙骨质界上的龈壁优于釉牙骨质界下的龈壁。结论 :脉冲 Nd:YAG激光照射可在一定程度上改善牙合壁的密合度 ,激光照射后再酸蚀能更好地防止微渗漏。脉冲 Nd:YAG激光照射龈壁 ,不仅能提高洞壁的密合度 ,并能较好地封闭洞壁表面的牙本质小管口 ,减少有害物质对牙髓的不良刺激 ,具有一定的临床应用价值。

AIM:To study the effect of pulse Nd:YAG laser on the adaptation of resin to dental hard tissue and to offer helpful reference for clinic on solving the microleakage.METHODS:60 human premolars were selected and divided into six groups randomly.For occlusal margin and gingival margin of each cavity were examined respectively.The cavities were conditioned as the design for each group and the resin was filled.The teeth interfaces were observed at ×10 magnification.RESULTS:Of the six occlusal groups, the microleakage percentage of the no-treatment group was highest and significantly higher than that of the other five groups(P<0.05).The microleakage percentage of lased+etched group was lowest and significantly lower than that of the lased group,the etched+lased group and the no-treatment group (P<0.05) .There was no statistical difference in the other four groups.Of the six gingival groups,there was no statistical difference between the lased group,the 10-3 solution group and the adaptation of the etched group (P>0.05),whether the gingival margins were above or below CEJ.The adaptation of the occlusal margins was better than that of the gingival margins and the adaptation of the gingival margins above CEJ was better than that below CEJ.CONCLUSION:The pulse Nd:YAG laser can improve the adaptation of occlusal margin to resin, especially in the group lased first then etched. For the gingival margins,the irradiation of the pulse Nd:YAG laser could not only improve the adaptation but also seal the orifices of dentinal tubules,which reduced stimulations to dental pulp through the dentinal tubules.