慢性根尖周炎微生物群落与临床症状的相关性分析

Correlation between clinical symptoms and microflora in root canals of chornic apical periodontitis

目的:应用PCR-DGGE技术对27例慢性根尖周炎患牙根管内的微生物群落进行检测,并分析其与临床症状产生的关系。方法:采集患牙根管内细菌样本,提取DNA,进行PCR-DGGE分析。结果:有症状组样本中优势菌属为10种,无症状组为14种。嗜血杆菌属、真杆菌属在有症状组中检出率高于无症状组(P<0.05);链球菌属、乳酸杆菌属在无症状组中检出率高于有症状组(P<0.05);脱硫球茎菌属为牙菌斑中罕见菌属,在无叩痛组中检出率高于有叩痛组(P<0.05),故认为其也为慢性根尖周炎的优势菌之一。结论:慢性根尖周炎患牙的根管中,嗜血杆菌属、真杆菌属与临床症状的产生有正相关性;链球菌属,乳酸杆菌属与临床症状的缺失有正相关性;脱硫球茎菌属与叩痛的产生有负相关性。

AIM ： To detect preponderant bacterium in the root canals of chornic periapical periodontitis by a polymerase chain reaction-denaturing gradient gel electrophoresis （PCR-DGGE） approach, and to analyze the rela- tionship between the bacterial presence and the clinical symptoms. METHODS： Tuenty-seven clinical samples were collected from the root canals of teeth with chronic periapical periodontitis. DNAs were extracted from the samples and identified by PCR-DGGE. RESULTS： Ten dominant microbial species were detected in symptomatic group, while 14 were detected in asymptomatie group. The detection rates of Haemophilus sp. and Flexistipes sp. were higher in symp- tomatic cases while Streptococcus sp. and Lactob^illus sp. were lower （ P 〈 0.05 ）. Desulfobulbus sp was rarely detected in subgingival plaque and was first detected in this study, indicating that it might be one of the dominant microbial spe- cies in chronic periapical periodontitis. The detection rate of Desulfobulbus sp. was higher in knock pain-free cases （ P 〈 0.05 ）. CONCLUSION ： In chronic periapical periodontitis samples, Haemophilus sp. and Flexistipes sp. show positive relationship with the presence of clinical symptoms while Streptococcus sp. and Lactobacillus sp. have positive relationship with the asymptoms. Desulfobulbus sp. has negative relationship with the presence of pain at percussion. DGGE is proved to be a powerful tool to analyze poly-microbes in root canals.