Kaiwar Anjali, Usha H L, Meena N, Ashwini P, Murthy Chethana S
Department of Conservative Dentistry and Endodontics, V.S. Dental College and Hospital, Bangalore, Karnataka, India.
Indian J Dent Res. 2013 Jan-Feb;24(1):14-8. doi: 10.4103/0970-9290.114916.
The aim of this study is to verify the disinfection of diode laser, following chemo-mechanical procedures against Enterococcus fecalis.
Crowns of 30 extracted premolar teeth were sectioned at the cemento- enamel junction. The canals were shaped using step-back technique to K-file #40. The teeth were randomly assigned to three groups and placed into nutrient broth containing bacterial suspension of Enterococcus fecalis. Group A received no laser radiation. Specimens of group B and C were treated with diode laser (Sirona) with energy set at 1.5 and 3 W, respectively. After laser irradiation, the teeth were placed in vials, which contained 2 mL of the nutrient broth. The vials were incubated at 37°C for 24 h. Grown colonies were identified by standard methods.
Statistical analysis used was the nonparametric Kruskal-Wallis test, with comparison using the Bonferroni methods of means.
Higher mean CFU/mL is recorded in Group A (without laser disinfection) followed by Group B (with 1.5 W laser disinfection) and Group C (with 3 W laser disinfection), respectively. The difference in CFU/mL between the three groups is found to be statistically significant ( P < 0.001).
The results of this research show that the 980 nm diode laser can eliminate bacteria that has immigrated into dentin, thus being able to increase the success rate in endodontic therapy.
本研究旨在验证在化学机械治疗程序后，二极管激光对粪肠球菌的消毒效果。
30颗拔除的前磨牙在牙骨质-釉质界处进行切割。使用逐步后退技术用K锉#40对根管进行预备。将牙齿随机分为三组，并置于含有粪肠球菌细菌悬液的营养肉汤中。A组未接受激光照射。B组和C组的样本分别用能量设置为1.5W和3W的二极管激光（西诺德）进行处理。激光照射后，将牙齿放入含有2mL营养肉汤的小瓶中。将小瓶在37°C下孵育24小时。通过标准方法鉴定生长的菌落。
所用统计分析方法为非参数Kruskal-Wallis检验，采用Bonferroni均值比较法。
A组（无激光消毒）记录的平均菌落形成单位/毫升（CFU/mL）最高，其次是B组（1.5W激光消毒）和C组（3W激光消毒）。发现三组之间CFU/mL的差异具有统计学意义（P<0.001）。
本研究结果表明，980nm二极管激光能够消除侵入牙本质的细菌，从而提高牙髓治疗的成功率。
