中文摘要：

目的：探讨牙周膜干细胞（periodontal ligament stem cells,PDLSCs）复合脱细胞真皮基质（acellular dermal matrix,ADM）对犬附着龈缺损模型再生修复效果,评估其用于附着龈缺损治疗的可行性.方法：原代培养犬PDLSCs,采用免疫磁珠法分离PDLSCs,将Brdu标记的PDLSCs与生物支架材料ADM复合,体外培养5天后植入犬附着龈缺损模型部位.8w时大体测量修复前后附着龈宽度、面积,Brdu免疫组化标记细胞的迁移、分化及转归,组织学观察PDLSCs-ADM复合物修复再生犬附着龈缺损效果.结果：PDLSCs-ADM复合体移植后8w,新生附着龈呈粉红色,与原黏膜组织形成明显界限,其宽度及面积增加量明显高于对照组.组织学结果显示ADM-PDLSCs组上皮结构类似正常附着龈,为复层鳞状上皮,但上皮钉突粗大、圆钝,无角化层.固有层血管、细胞成分较对照组明显增多,胶原纤维丰富.免疫组化显示ADM-PDLSCs组Brdu标记的阳性细胞在上皮基底层及黏膜下层表达,而ADM对照组无表达.结论：PDLSCs复合ADM较ADM单独使用能显著提高犬附着龈缺损修复效果,本实验为牙龈缺损的生物再生修复提供了有效途径.

英文摘要：

Objective： To explore the therapic effects of periodontal ligament stem cells （PDLSCs） in combination with acellular dermal matrix （ADM） on defects in dog attached gingival. Methods： Dog PDLSCs were cultured and isolated by irnmunomagnetic cell selection technique, then the Brdu positive PDLSCs for cell tracking were seeded on scaffold of ADM. After incubated for 5 days, the constructs were transplanted to rebuild the defects of dog attached gingival models. The newly formed attached gingival were observed by gross and histological observation after 8 wks post-operation. Im- munohistochemical analysis of Brdu was performed as a cell tracking technique for migration, differentiation and formation of PDLSCs. Results： 8 wks after the PDLSCs-ADM constructs transplanted, the newly formed attached gingival were ob- served at the sites of defects in pink color, which is significantly different from the original gingival. The increase of the length and the area of the newly formed tissue in the PDLSCs-ADM group is statistically larger than that of the ADM group and natural gingival group. The histological observations showed that there was gingival epthelial-like tissue around the de- fects with connective tissue covered with stratified squamous epithelium. However, the epithelium rete pegs in the PDLSCs-ADM is stronger and shorter than those of the ADM group and the normal group and no layer of keratinization formed. Moreover, more cells, blood vessels and fiber bundles could be found in the PDLSCs-ADM group than the two oth-er groups. Irnmunohistochemical staining showed that the Brdu positive cells could only been found in the stratum basale of the epithelial layer and connective tissue of the PDLSCs-ADM group. Conclusion： PDLSCs combined with ADM may sig- nificantly promote the regeneration and restoration of attached gingival defects on dogs, and this may provide available and useful way for gingival defect by bioengineering technique.