Cementoblast delivery for periodontal tissue engineering
Cementoblast delivery for periodontal tissue engineering
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DOI：
10.1902/jop.2004.75.1.154
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发表时间：
2004-01-01
影响因子：
4.3
通讯作者：
Somerman, MJ
中科院分区：
文献类型：
--
作者：
Zhao, M;Jin, QM;Somerman, MJ
背景：牙周病后可预测的牙周再生是治疗的主要目标。这个概念的调查证明的目的是评估成牙骨质细胞和牙囊细胞的能力，以促进牙周再生的啮齿动物牙周开窗model.Methods：颊侧的第一下颌磨牙的远端根剥脱的牙周膜（PDL），牙骨质，和表面的牙本质通过一个骨窗创建双边在12只无胸腺大鼠。将治疗的缺损分为三组：1）单独载体（PLGA聚合物海绵），2）载体+卵泡细胞，3）载体+成牙骨质细胞。通过可生物降解的PLGA聚合物海绵将培养的小鼠初级卵泡细胞和永生化的成牙骨质细胞递送到缺损处，并在术后3周和6周取回下颌骨进行组织学评价。原位杂交，骨涎蛋白（BSP）和骨钙素（OCN）的基因表达，并进一步做了3周的标本histomorphometric analysis.Results：3周后，组织学与载体单独处理的缺陷表明，PLGA颗粒，纤维组织，和新形成的骨缺损区域内分散。用载体+毛囊细胞处理的缺损具有相似的外观，但骨形成较少。相比之下，在用载体+成牙骨质细胞治疗的缺损中，在愈合部位观察到矿化组织，并向牙根面、PDL区域延伸，并且侧向超出骨的颊板包膜。此时，在任何组中均未观察到PDL-骨纤维附着。原位杂交结果显示，成牙骨质细胞形成的矿化组织中BSP和OCN基因均呈强信号，证实其为牙骨质或骨。在第3周观察到的变化在第6周也观察到。成牙骨质细胞治疗和载体单独治疗的缺损表现出完整的骨桥和PDL形成，而卵泡细胞治疗的缺损显示出最小的成骨证据。两组根面均无沿着新牙骨质形成。成牙骨质细胞处理的缺损填充有小梁矿化组织，与3周时观察到的相似，但更成熟。此外，PDL区域保持有组织良好的胶原纤维，将相邻骨连接到牙根表面上观察到的骨水泥样组织薄层。在两个6周的成牙骨质细胞处理的标本中的植入物的浅表部分观察到肿瘤的变化，可能部分是由于SV 40转化的性质的植入cellline.Conclusions：这项试点研究表明，成牙骨质细胞有显着的能力，通过聚合物海绵传递时，诱导牙周伤口矿化，而植入的牙囊细胞似乎抑制牙周愈合。这些结果证实了不同类型的细胞在体内的选择性行为，并支持成牙骨质细胞作为更好地了解牙周再生和牙骨质形成的工具的作用。
Background: Predictable periodontal regeneration following periodontal disease is a major goal of therapy. The objective of this proof of concept investigation was to evaluate the ability of cementoblasts and dental follicle cells to promote periodontal regeneration in a rodent periodontal fenestration model.Methods: The buccal aspect of the distal root of the first mandibular molar was denuded of its periodontal ligament (PDL), cementum, and superficial dentin through a bony window created bilaterally in 12 athymic rats. Treated defects were divided into three groups: 1) carrier alone (PLGA polymer sponges), 2) carrier + follicle cells, and 3) carrier + cementoblasts. Cultured murine primary follicle cells and immortalized cementoblasts were delivered to the defects via biodegradable PLGA polymer sponges, and mandibulae were retrieved 3 weeks and 6 weeks post-surgery for histological evaluation. In situ hybridization, for gene expression of bone sialoprotein (BSP) and osteocalcin (OCN), and histomorphometric analysis were further done on 3-week specimens.Results: Three weeks after surgery, histology of defects treated with carrier alone indicated PLGA particles, fibrous tissue, and newly formed bone scattered within the defect area. Defects treated with carrier + follicle cells had a similar appearance, but with less formation of bone. In contrast, in defects treated with carrier + cementoblasts, mineralized tissues were noted at the healing site with extension toward the root surface, PDL region, and laterally beyond the buccal plate envelope of bone. No PDL-bone fibrous attachment was observed in any of the groups at this point. In situ hybridization showed that the mineralized tissue formed by cementoblasts gave strong signals for both BSP and OCN genes, confirming its nature as cementum or bone. The changes noted at 3 weeks were also observed at 6 weeks. Cementoblast-treated and carrier alone-treated defects exhibited complete bone bridging and PDL formation, whereas follicle cell-treated defects showed minimal evidence of osteogenesis. No new cementum was formed along the root surface in the above two groups. Cementoblast-treated defects were filled with trabeculated mineralized tissue similar to, but more mature, than that seen at 3 weeks. Furthermore, the PDL region was maintained with well-organized Collagen fibers connecting the adjacent bone to a thin layer of cementum-like tissue observed on the root surface. Neoplastic changes were observed at the superficial portions of the implants in two of the 6-week cementoblast-treated specimens, possibly due in part to the SV40-transformed nature of the implanted cell line.Conclusions: This pilot study demonstrates that cementoblasts have a marked ability to induce mineralization in periodontal wounds when delivered via polymer sponges, while implanted dental follicle cells seem to inhibit periodontal healing. These results confirm the selective behaviors of different cell types in vivo and support the role of cementoblasts as a tool to better understand periodontal regeneration and cementogenesis.