上皮根鞘在无细胞牙骨质和细胞牙骨质形成中的作用研究

目的 观察无细胞牙骨质和细胞牙骨质发育时上皮根鞘细胞的增殖、凋亡的表达,探讨上皮根鞘在非细胞牙骨质和细胞牙骨质形成不同作用.方法 TUNEL法检测牙根发育中上皮根鞘细胞凋亡的情况.比较非细胞和细胞牙骨质形成时上皮根鞘细胞和牙周膜细胞的凋亡阳性表达指数,取α=0.05水准.SP免疫组化法检测增殖细胞核抗原(PCNA).结果 小鼠出生后第9天,无细胞牙骨质形成阶段,上皮根鞘细胞与牙周组织凋亡阳性表达指数未见显著性差异;出生后第19天,牙根根1/3为细胞牙骨质所覆盖,此时上皮根鞘细胞凋亡阳性表达指数高于牙周组织(P<0.05).结论 细胞凋亡调控上皮根鞘细胞的转归;上皮根鞘细胞在无细胞牙骨质和细胞牙骨质形成中的作用不尽相同.

Role of Hertwig’s epithelial root sheath in acellular and cellular cementogenesis

Objective To analyze apoptosis,proliferation and expression of mineralization related factors in HERS(Hertwig’s epithelial root sheath) and to evaluate role of HERS in acellular and cellular cementogenesis.Methods Apoptosis was identified by TUNEL method.Differences between the two groups were analyzed using t-test.SP immunohistochemical method was used to detect the expression of PCNA.Results Apoptosis in cellular cementogenesis was significant difference between HERS and PDL(periodontal ligament)(P< 0.05).Conclusion Apoptosis plays an essential role in fate of HERS.Roles of HERS in acellular and cellular cementogenesis are not the same.