Technical Development for Making the Artificial Dental Root with Periodontal Ligament

本研究的目的是建立一种功能接近天然牙的人工牙根。在研制钛人工根表面牙周膜的过程中，我们对牙周膜细胞的体内外特性进行了研究。主要研究结果如下：1.研究结果。用改进的方法可获得人PDL细胞的原代培养，成功率达90%以上。2.人PDL培养细胞可吸附在钛表面。3.Cell-Tak涂层可促进人PDL细胞在钛表面的吸收。4.在添加10%人血清的培养液中，PDL细胞的生长速度最快。5.抛光和喷砂处理的钛表面适合PDL细胞的生长。6.PDL细胞产生的因子能抑制体外培养的外周血淋巴细胞和单核细胞向破骨细胞的诱导。7.牙槽骨来源的牙龈细胞和成骨细胞不产生该抑制因子。8.牙周病损组织中某些细菌的刺激可增加PBL诱导的破骨细胞数量，但加入PDL细胞培养液后，细菌刺激的PBL诱导的破骨细胞数量明显减少。9.与PBL共培养不抑制PDL细胞的ALPase活性。10.与牙周细胞相比，PDL细胞的ALPase活性和胶原合成显著增加。11.10代细胞的传代对PDL细胞的分化功能无不良影响，钛的浇注系统、包埋剂的研制以及直浇道和通风口的设计也得到了技术上的改进。

The purpose of this study is the establishment of artificial dental root, which is functionally close to the natural teeth. In the process of the developing technique to make periodontal ligament (PDL) on the surface of titanium artificial root, we investigated the character of PDL cells invitro or in vivo. The main results observed were as follows.1. The primary cultivation of human PDL cells could be obtained at the rate of success 90% or more with our improved method. 2. Human PDL cultured cells could be adsorbed on the titanium surface. 3. Cell-Tak coating could accelerate the absorbance of human PDL cells onto titanium surface. 4. The growth velocity of PDL cells was the most accelerated in the medium supplemented with 10% human serum. 5. The polished and glass beads-sandblasted titanium surface were appropriate for the growth of PDL cells. 6. The factor produced from PDL cells could suppress the induction of osteoclast from the cultured peripheral blood lymphocytes and monocytes (PBL). 7. Gingival cells and osteoblast originated from alveolar bone didn't produce this suppressing factor. 8. Although number of osteoclast induced from the PBL could be increased by the stimulation of some bacteria from periodontal lesion, the addition of the culture fluid of PDL cells significantly decreased the induction of osteoclast from PBL stimulated with bacterias. 9. ALPase activity of PDL cells was not suppressed by co-culture with PBL. 10. As compared with gingival cells, ALPase activity and collagen synthesis of PDL cells was remarkably higher. 11.10th Passage of cells did not show in any defective effect on differentiating function of PDL cells.Concerning casting system of titanium, development on the investment and the technical improvement on design of sprue and vent were also attained.