摘要
目的探讨氢氧化钙根管内封药对慢性根尖周炎根管内细菌的作用。方法采集5例慢性根尖周炎患者感染根管3个阶段的细菌样本,分别为治疗前、氢氧化钙封药2周、取出氢氧化钙封入无菌干棉球2周。采用PCR-DGGE技术检测根管内细菌变化,并对其中3例进行克隆测序分析。结果 5例样本共检测出41条谱带,其中治疗前均有条带,条带数3～7条,平均为5.4条;氢氧化钙封药2周均无条带;取出氢氧化钙封入无菌干棉球2周,3例有条带,条带数为4～7条,平均为5.1条;另2例5条带。将33条带进行纯化、克隆、测序分析,平均每条带含2.2种细菌;共得到30种不同菌属,分别属于不同菌门,12种属于厚壁菌门(占40%),其他细菌属于拟杆菌门(5种,16.7%),放线菌门(4种,13.3%),变形菌门(3种,10%),脱铁菌门(2种,6.67%)梭杆菌门(1种),螺旋体门(1种),2种未知菌属。其中包含9种未培养出的细菌。结论氢氧化钙作为感染根管消毒药物,能使细菌量急剧减少,但不能杀灭所有细菌,若根管不能及时封闭,残留细菌仍可能会继续增殖。
Objective To evaluate the antibacterial effect of calcium hydroxide in infected root canals.Methods Five teeth with asymptomatic endodontic infections and chronic periodontitis were included.Bacterial samples were taken from the five teeth before treatment（S_1）,after a 2-weeks medication with calcium hydroxide paste（S_2）,and following a 2-weeks＂hollow canal＂period（S_3）.DNA was extracted,and part of 16S rDNA of all bacteria was amplified by PCR and separated by DGGE.Thirty-three visible bands of 3 samples were excised,purified,cloned and sequenced.Results A total of 41 visible bands were detected by DGGE.At S_1,all samples displayed bands（indicating bacteria）.The number of bands ranged from 3 to 7 with a mean of 5.4.At S_2,none of the samples showed bands.At S_3,3 samples harbored bands,and the number of bands ranged from 4 to 7,with a mean of 5.1.16SrDNA sequence analysis of the excised bands demonstrated 30 taxa,among which,12 taxa（40%） belong to Firmicutes.The other phyla were Bacteroidetes（5 taxa）,Actinobacteria（4 taxa）,Proteobacteria（3 taxa）,Deferribacteres（2 taxa）,Fusobacteria（1 taxa）,Spirochaetes（1 taxa） and 2 unknown bacteria.Proteinobacteria and treponem were only present at S_3.Conclusion Calcium hydroxide has a decent antibacterial ability and can decrease bacterial load.But It fails to render the root canal bacteria free.When the canal is left unobturated, remanant bacteria would survive and multiply.
出处
《北京口腔医学》
CAS
2011年第6期312-317,共6页
Beijing Journal of Stomatology
基金
国家自然科学基金(30872877)
北京市自然科学基金(7102069)
关键词
感染根管
氢氧化钙
变性梯度凝胶电泳
测序
Infected root canal
Calcium hydroxide
Denaturing gradient gel electropheresis（DGGE）
Sequencing
