持续性根尖周炎患牙根管外细菌定植状态的观察  

Status of extraradicular bacterial colonization in teeth with persistent periapical periodontitis

作　　者：王兢兢[1] 王娟[2,3] 

机构地区：[1]南京市妇幼保健院口腔科,江苏南京210004 [2]南京医科大学口腔疾病研究江苏省重点实验室 [3]南京医科大学附属口腔医院牙体牙髓科,江苏南京210029

出　　处：《口腔医学》2015年第2期85-88,共4页Stomatology

基　　金：国家自然科学基金青年基金(81300868);江苏省高校自然科学研究项目(13KJB320008);江苏高校优势学科建设工程资助项目(2014-37)

摘　　要：目的了解根管外细菌在持续性根尖周炎患牙根尖区根面上的定植状态,以探讨根管外生物膜在持续性根尖周感染致病机制中的意义。方法采用扫描电镜与组织病理学染色相结合的方法,观察正畸拔除牙（5例）和持续性根尖周炎（10例）患牙根尖区根管外生物膜的分布和结构。拔牙和根尖外科手术过程获得的根尖样本经洗涤、固定和冷冻干燥后,用扫描电镜（无损伤性）观察根尖区外表面的超微结构。同样的样本再经过脱钙和横断面连续组织切片后,进行细菌Brown＆Brenn染色观察。结果在扫描电镜下,正畸拔除牙的根尖区结构无异常。所有持续性根尖周炎患牙的根尖区呈现病变状态,根尖区几乎没有胶原纤维的覆盖,牙骨质暴露和吸收,其表面观察到根管外生物膜结构。细菌Brown＆Brenn染色结果显示,根管外生物膜由大量基质成分包裹的红染的革兰阴性菌和呈紫色的革兰阳性菌相互交织排列形成,其厚度约为18～30μm。结论根管外细菌以生物膜形式定植在持续性根尖周炎患牙根尖区外表面,根管外生物膜的存在有可能是导致持续性根尖周感染的重要因素之一。Objective To investigate the presence and distribution of extraradicular biofilm on the apical root surfaces of human teeth with persistent periapical periodontitis. Methods Ten apex samples of single-rooted teeth with persistent periapical periodontitis were collected during root-end surgery. Five single-rooted teeth extracted for orthodontic reasons were selected as controls. All samples were initially evaluated using scanning electron microscopy after freeze-drying. The same samples were then processed with Brown and Brenn- modified Gram staining. Results The root outside surfaces of teeth extracted for orthodontic reasons was covered by fibers and there was no cementum resorption or microorganisms. Extraradicular biofilm and cementum resorption were found in all teeth with persistent periapical periodontitis. The extraradicular bacteria were predominantly rods and filaments, and surrounded by a varying amount of amor- phous extracellular material. Conclusions The extraradicular biofilm may be one of the important factors which cause persistent peria- pical periodontitis.

关 键 词：持续性根尖周炎 根管外生物膜 扫描电镜 

分 类 号：R780.2[医药卫生—口腔医学]