Araújo M G, Berglundh T, Lindhe J
Department of Periodontology, Faculty of Odontology, Göteborg University, Sweden.
J Clin Periodontol. 1998 Mar;25(3):253-9. doi: 10.1111/j.1600-051x.1998.tb02436.x.
The aim of the present study was to describe the periodontal tissue that formed after GTR when different resorbable barriers were applied to degree III furcation defects. The study was performed in 5 foxhound dogs. The 2nd and 4th premolars in both sides of the mandible were extracted. Degree III furcation defects were produced in the 3rd mandibular premolars. 5 weeks later, GTR therapy using a barrier composed by a polylactide-glycolide copolymer was performed on one quadrant (group A). In the contralateral quadrant, a barrier made of polylactide and citric acid ester (group B) was used. The dogs were sacrificed 6 months after reconstructive therapy. Tissue blocks containing the experimental teeth were excised, demineralised in EDTA and embedded in paraffin. Serial sections were cut in the mesio-distal plane and parallel with the long axis of the roots. The microtome was set at 7 microm. The sections were stained in hematoxyline and eosin. From each biopsy, 3 sections representing the central part of the furcation were selected for light microscopic examination. In the healed furcation sites, descriptive histological analysis and histomorphometric measurements of the newly formed tissues were performed. In both groups the root surface of the healed furcation defects was covered by a cellular, extrinsic-intrinsic fibers type cementum. The composition of the newly formed periodontal ligament was similar in both groups. The proportions of bone, bone marrow and periodontal ligament, however, were substantially larger in group A than in group B. In Group B, an area in the previous furcation defect was consistently occupied by a granuloma. It is suggested that the presence of the granuloma in the healed furcation defect prevented bone regrowth.
本研究的目的是描述在III度根分叉病变应用不同可吸收屏障进行引导组织再生（GTR）后形成的牙周组织。该研究在5只猎狐犬身上进行。拔除下颌两侧的第二和第四前磨牙。在下颌第三前磨牙制造III度根分叉病变。5周后，在一个象限使用由聚丙交酯-乙交酯共聚物组成的屏障进行GTR治疗（A组）。在对侧象限，使用由聚丙交酯和柠檬酸酯制成的屏障（B组）。重建治疗6个月后处死实验犬。切除包含实验牙的组织块，用乙二胺四乙酸（EDTA）脱矿并石蜡包埋。在近远中平面并与牙根长轴平行切取连续切片。切片厚度设定为7微米。切片进行苏木精和伊红染色。从每次活检中，选择3个代表根分叉中央部分的切片进行光学显微镜检查。在愈合的根分叉部位，对新形成的组织进行描述性组织学分析和组织形态计量学测量。在两组中，愈合的根分叉病变的根面均被细胞性、外源性-内源性纤维型牙骨质覆盖。两组中新形成的牙周膜组成相似。然而，A组中骨、骨髓和牙周膜的比例明显大于B组。在B组中，先前根分叉病变区域持续被肉芽肿占据。提示愈合的根分叉病变中肉芽肿的存在阻止了骨再生。
