Interrelationship between epithelial and connective tissue attachments during wound healing of the periodontal tissues.

本研究的目的是研究牙周组织伤口愈合过程中上皮组织和结缔组织附着物之间的相互关系。在大鼠上颌第一磨牙和第二磨牙之间插入弹性橡胶。一周后取出橡胶，用手术刀在暴露的根表面的最顶端区域做一个缺口。饲喂粉末状饲料，取下弹性橡胶后立即至24周处死。光镜、免疫组化、电镜观察牙周组织再生变化。切除一周后，大部分暴露的根表面被渗出细胞和炎症细胞覆盖，尽管再生的上皮细胞形成口袋上皮。4周后，缺口被袋上皮细胞填满，根表面在更顶端的位置被长连接上皮覆盖。随着时间的推移，长连接上皮的长度和宽度有减小的趋势。拔牙20周后，缺口根表面被结缔组织覆盖，结缔组织在排列和形态上与牙周韧带非常相似。免疫组化研究显示，层粘连蛋白对上皮附着体基底层呈阳性，纤维连接蛋白对结缔组织附着体基底层呈阳性。由此提示，大鼠暴露根表面的结缔组织附着可以取代长连接上皮形成的上皮附着。

The purpose of this study was to investigate the interrelationship between epithelial and connective tissue attachments during wound healing of the periodontal tissues. Elastic rubber was inserted between the first and second molars of the maxilla in rats. The rubber was removed after one week, and a notch was made on the most apical region of the exposed root surface using a scalpel. The animals were fed a powdered fed, and sacrificed from immediately to 24 weeks after the removal of the elastic rubber. Regenerative changes of the periodontal tissues were observed light microscopically, immunohistochemically and electron microscopically. One week after the removal, the majority of the exposed root surface was covered by exudate and inflammatory cells although regenerative epithelial cells revealed to form a pocket epithelium. The notch was filled by epithelial cells of the pocket epitheium and the root surface was covered by a long junctional epithelium at the more apical site after four weeks. The long junctional epithelium tended to decrease in length and width with the passage of time. Twenty weeks after the removal, the notched root surface was covered by connective tissue which was closely similar in arrangement and morphology to the periodontal ligament. Immunohistochemical studies showed that laminin was positive to the basal lamina of the epithelial attachment and fibronectin was positive to that of the connective tissue attachment. From these results it is suggested that the epithelial attachment forming by a long junctional epithelium can be replaced by connective tissue attachment on the exposed root surface in rats.