Cardoso Flávia Goulart da Rosa, Martinho Frederico Canato, Ferreira Nádia de Souza, Prado Renata Falchete do, Manhães-Júnior Luiz Roberto Coutinho, Rocco Marco Antônio, Valera Marcia Carneiro
Department of Restorative Dentistry, Institute of Science and Technology, UNESP - Univ Estadual Paulista, São José dos Campos, SP, Brazil.
Department of Dentistry, Endodontic Division, University of Taubaté - UNITAU, Taubaté, SP, Brazil.
Braz Dent J. 2019 Mar-Apr;30(2):117-122. doi: 10.1590/0103-6440201902239. Epub 2019 Apr 4.
This clinical study was conducted to correlate the levels of endotoxins and culturable bacteria found in primary endodontic infection (PEI) with the volume of root canal determined by using Cone Beam Computed Tomography (CBCT); and to evaluate the bacterial diversity correlating with clinical features. Twenty patients with PEI were selected and clinical features were recorded. The volume (mm3) of root canal was determined by CBCT analysis. Root canal samples were analyzed by using kinetic LAL-assay test to determine the levels of endotoxins and anaerobic technique to determine the bacterial count (CFU/mL). DNA was extracted from all samples to determine bacterial diversity and quantified by using Checkerboard-DNA-DNA- Hybridization. Culturable bacteria and endotoxins were detected in 100% of the root canal samples. Linear regression analysis revealed a correlation between root canal volume and presence of anaerobic bacteria (p<0.05). Positive correlations were found between bacteria species and presence of different clinical features (p<0.05). After grouping the bacteria species into bacterial complexes, positive associations were found between green, orange and red complexes with presence of sinus tract (p<0.05). This clinical study revealed that larger root canals hold higher levels of culturable bacteria in PEI. Thus, the interaction of different virulent bacteria species in complexes seems to play an important role in the development of clinical features.
本临床研究旨在将原发性牙髓感染（PEI）中发现的内毒素水平和可培养细菌与使用锥形束计算机断层扫描（CBCT）确定的根管容积相关联；并评估与临床特征相关的细菌多样性。选择了20例PEI患者并记录其临床特征。通过CBCT分析确定根管容积（mm³）。使用动态鲎试剂法检测根管样本以确定内毒素水平，采用厌氧技术确定细菌计数（CFU/mL）。从所有样本中提取DNA以确定细菌多样性，并使用棋盘式DNA-DNA杂交法进行定量。在100%的根管样本中检测到可培养细菌和内毒素。线性回归分析显示根管容积与厌氧菌的存在之间存在相关性（p<0.05）。发现细菌种类与不同临床特征的存在之间存在正相关（p<0.05）。将细菌种类分组为细菌复合体后，发现绿色、橙色和红色复合体与窦道的存在之间存在正相关（p<0.05）。这项临床研究表明，在PEI中，较大的根管含有更高水平的可培养细菌。因此，复合体中不同毒力细菌种类的相互作用似乎在临床特征的发展中起重要作用。
