Objective: The aim of this study was to explore the theoretical framework of cells and the forms of osteogenesis in the mechanism by which demineralized dentin matrix (DDM) induces osteogenesis.
Methods: A total of 24 New Zealand rabbits were used in this study. A total of 4 erector spinae bags were created in each animal. A total of 3 erector spinae bags were implanted with DDM by random selection, whereas the remaining one erector spinae bag was not implanted with DDM. The rabbits were sacrificed after 1, 2, 3, 4, 8, 12, 16, and 20 weeks, and the samples were obtained. The samples were examined by hematoxylin-eosin (HE), tartrate-resistant acid phosphatase (TRAP), and immunohistochemical staining to identify the mesenchymal stem cells, osteoblasts, chondrocytes, and osteoclasts.
Results: The results of HE staining showed that in the third week, cartilage- and bone-like matrices, as well as the osteoblast-like cells, were observed. The results of immunohistochemical staining showed that the expressions of CD44, alkaline phosphatase (ALP), and collagen Ⅱ were statistically significant (P<0.05).
Conclusions: DDM has good histocompatibility and osteoinduction. In addition, induced ectopic osteogenesis mode mainly occurs in the endochondral bone.
目的 探讨脱矿牙本质基质（DDM）诱导成骨机制的细胞理论框架和成骨方式。方法 在24只新西兰大耳白兔双侧竖脊肌区制备4个肌袋位点，随机选取3个位点为实验位点，植入DDM，另一位点为对照位点，不植入任何材料。术后1、2、3、4、8、12、16和20周处死动物，制作组织标本，应用苏木精-伊红（HE）染色、抗酒石酸酸性磷酸酶（TRAP）染色和免疫组织化学染色对间充质干细胞、成骨细胞、软骨细胞及破骨细胞进行鉴定分析。结果 HE染色显示：3周时，实验组可见软骨样基质、骨样基质和成骨样细胞。免疫组化染色显示：各时间点CD44、碱性磷酸酶（ALP）和Ⅱ型胶原表达有统计学意义（P<0.05）。结论 DDM具有良好骨诱导性和组织相容性，其诱导成骨的主要方式可能为软骨内成骨。.
Keywords: chondrocytes; demineralized dentin matrix; mesenchymal stem cells; osteoblast; osteoinduction.