Das Maneesha, Kumar G Anil, Ramesh Sindhu, Garapati Surendranath, Sharma Deepak
Department of Conservative Dentistry and Endodontics, Saraswati-Dhanwantari Dental College and Hospital Parbhani, Maharashtra, India.
J Contemp Dent Pract. 2013 Mar 1;14(2):183-7. doi: 10.5005/jp-journals-10024-1297.
Smear layer is a negative factor which prevents adhesion of the filling material to the dentinal walls. Recent advances in dental research have incorporated lasers as a potential adjunct in root canal treatment by removing the smear layer before filling the root canal system, enhancing the adhesion of sealers to dentin and improving the sealing ability.
To evaluate the microtensile bond strength of AH-Plus resin-based sealer to dentin after treatment with 980 nm diode and 1,064 nm neodymium-doped:yttrium aluminum garnet (Nd:YAG) laser in vitro.
Thirty specimens prepared for three groups namely group I (control), group II (980 nm diode-lased specimens) and group III (Nd:YAG-lased specimens). One tooth from each group was observed under scanning electron microscope for evaluation of intracanal root dentin morphology. Remaining specimens were used for making microsections by hard tissue microtome. Specimens for groups II and III were lased with 980 nm diode and 1,064 nm Nd:YAG laser. AH Plus sealer was applied onto specimens and mounted onto Instron universal testing machine for microtensile bond strength testing. Results were subjected to statistical analysis using one-way analysis of variance (ANOVA) and Tukey's test.
Group III Nd:YAG had maximum mean microtensile bond strength values (11.558 ± 0.869), followed by group II diode (9.073 ± 0.468) and group I control (6.05 ± 0.036). Statistically significant differences were seen among all the groups. SEM analysis shows removal of smear layer in both groups II and III.
Both Nd:YAG and diode laser were more effective than control group in improving the microtensile bond strength of AH Plus sealer to dentin.
Lasers have the potential to increase the adhesiveness of root canal sealer to dentin surface, thereby improving the quality of root canal obturation.
玷污层是阻碍充填材料与牙本质壁黏附的一个不利因素。牙科研究的最新进展已将激光作为根管治疗中的一种潜在辅助手段,即在充填根管系统之前去除玷污层,增强封闭剂与牙本质的黏附力并提高封闭能力。
在体外评估经980nm二极管激光和1064nm掺钕钇铝石榴石(Nd:YAG)激光处理后AH-Plus树脂基封闭剂与牙本质之间的微拉伸粘结强度。
制备30个样本,分为三组,即第一组(对照组)、第二组(980nm二极管激光照射样本)和第三组(Nd:YAG激光照射样本)。每组取一颗牙齿在扫描电子显微镜下观察根管内牙根牙本质形态。其余样本用硬组织切片机制作薄片。第二组和第三组样本分别用980nm二极管激光和1064nm Nd:YAG激光照射。将AH Plus封闭剂应用于样本上,并安装在英斯特朗万能试验机上进行微拉伸粘结强度测试。结果采用单因素方差分析(ANOVA)和Tukey检验进行统计学分析。
第三组Nd:YAG的平均微拉伸粘结强度值最高(11.558±0.869),其次是第二组二极管激光照射组(9.073±0.468),第一组对照组最低(6.05±0.036)。所有组之间均存在统计学显著差异。扫描电子显微镜分析显示第二组和第三组的玷污层均被去除。
Nd:YAG激光和二极管激光在提高AH Plus封闭剂与牙本质的微拉伸粘结强度方面均比对照组更有效。
激光有潜力增加根管封闭剂与牙本质表面的黏附性,从而提高根管充填质量。