Lopes Fabiane Carneiro, Roperto Renato, Akkus Anna, Silva Sousa Yara Teresinha Corrêa, Sousa-Neto Manoel D
Department of Restorative Dentistry, School of Dentistry of Ribeirão Preto, University of São Paulo - USP, Ribeirão Preto, SP, Brazil.
Department of Comprehensive Care, School of Dental Medicine, Case Western Reserve University - CWRU, Cleveland, Ohio.
Microsc Res Tech. 2018 Sep;81(9):973-979. doi: 10.1002/jemt.23060. Epub 2018 Oct 8.
The aim of this study was to evaluate the chemical and morphological effects of different lasers as a final surface treatment for endodontic therapy through energy dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) respectively. Twenty-five maxillary canines were selected and instrumented with K3 system. Roots were randomly distributed into five groups (n = 5) according to the surface treatment: GI (distilled water), GII (NaOCl + EDTA), GIII (NaOCl + EDTA + 980 nm diode laser), GIV (NaOCl + EDTA+ 1,064 nm Nd:YAG laser), and GV (NaOCl + EDTA+ 2,780 nm Er, Cr:YSGG laser). Lasers were applied for 20 s and samples were bisected, exposing the treated surface and then subjected to elements quantification by EDS and morphological evaluation by scanning electron microscope (SEM). EDS data were submitted to ANOVA-two way, and SEM scores were submitted to two-way Kruskal-Wallis and Dunn's tests. The EDS analysis showed no difference for the chemical elements and Ca/P ratio between groups (p > .05). Statistical analysis showed more intense results for GV and less intense results for GI (p < .05). The GIII showed an amorphous organic matrix surface, while GV provided greater removal of intertubular dentin forming craters, and GIV promoted dentin fusion. The EDS method used in this study was not able to verify any chemical changes in root canal dentin; Nd:YAG, Er, Cr:YSGG, and 980 nm diode laser were capable of modifying the dentin morphology, correlating characteristics features for each one, which are essential clinical knowledge to establish the correct indication for each case. RESEARCH HIGHLIGHTS: EDS was not able to verify any chemical changes in root canal dentin after 980 nm diode, Nd:YAG and Er;Cr:YSGG laser treatments Nd:YAG, Er, Cr:YSGG, and 980 nm diode laser modified dentin morphology, correlating characteristics features for each one.
本研究的目的是分别通过能量色散X射线光谱法（EDS）和扫描电子显微镜（SEM）评估不同激光作为牙髓治疗最终表面处理的化学和形态学效果。选取25颗上颌尖牙，用K3系统进行预备。根据表面处理方法将牙根随机分为五组（n = 5）：GI组（蒸馏水）、GII组（次氯酸钠+乙二胺四乙酸）、GIII组（次氯酸钠+乙二胺四乙酸+980 nm二极管激光）、GIV组（次氯酸钠+乙二胺四乙酸+1064 nm钕:钇铝石榴石激光）和GV组（次氯酸钠+乙二胺四乙酸+2780 nm铒铬:钇钪镓石榴石激光）。激光照射20秒后，将样本一分为二，暴露处理过 的表面，然后通过EDS进行元素定量分析，并通过扫描电子显微镜（SEM）进行形态学评估。EDS数据进行双向方差分析（ANOVA），SEM评分进行双向Kruskal-Wallis检验和邓恩检验。EDS分析显示，各组之间的化学元素和钙磷比没有差异（p＞0.05）。统计分析显示，GV组的结果更明显，GI组的结果不明显（p＜0.05）。GIII组显示出无定形有机基质表面，而GV组能更有效地去除管间牙本质，形成凹坑，GIV组促进牙本质融合。本研究中使用的EDS方法无法验证根管牙本质的任何化学变化；钕:钇铝石榴石激光、铒铬:钇钪镓石榴石激光和980 nm二极管激光能够改变牙本质形态，将各自的特征关联起来，这是确定每个病例正确适应症的重要临床知识。研究亮点：980 nm二极管激光、钕:钇铝石榴石激光和铒铬:钇钪镓石榴石激光治疗后，EDS无法验证根管牙本质的任何化学变化；钕:钇铝石榴石激光、铒铬:钇钪镓石榴石激光和980 nm二极管激光改变了牙本质形态，将各自的特征关联起来。
