Biological control for the rate of orthodontic tooth movement and root resorption

正畸牙齿移动取决于牙齿上的机械应力，但存在各种问题，例如牙根吸收、治疗时间长、疼痛、由于多托槽系统而导致的不良口腔卫生等。因此，对牙齿移动和支抗控制应建立生物学和生理学控制，而不仅仅依赖于机械应力.为抑制实验性牙移动后的复发，我们在牙槽骨压力侧局部注射1，25（OH）_2D_3或TGF-β。1，25（OH）_2D_3注射组对复发无影响。而24，25（OH）_2D_3或TGF-β治疗组则表现为破骨细胞少，成骨细胞成骨活跃。压力侧骨体积和成骨面积增加，骨吸收面积和破骨细胞数量减少. HVJ脂质体法是一种高效、 关于我们 与腺病毒载体介导的基因递送相比，无毒的体内基因转移。本实验旨在探讨HVJ脂质体法制备大鼠实验性牙齿移动模型的最佳条件。(1)采用HVJ-脂质体法将荧光素酶基因转染至小鼠骨髓间充质细胞。进行荧光素酶报告基因测定以评价递送速率。(2)采用HVJ-脂质体法将β-半乳糖苷酶基因（LacZ）导入大鼠上颌，在实验性牙齿移动过程中进行表达。在基因导入后三天，进行X-gal染色以评估递送。这些研究表明HVJ脂质体基因转染对实验性牙齿移动是有效的.用HVJ脂质体转染CTGF基因后，进行大鼠实验性牙齿移动。分别于牙齿移动后第1、3、5、7、15天解剖上颌骨。采用原位杂交和免疫组化技术检测牙周组织中CTGF的表达。少

Orthodontic tooth movement depends on the mechanical stress onto the tooth, but there are various problems, such as root resorption, long treatment period, pain, undesirable oral hygiene due to the multibracket system and others. Therefore, the biological and physiological control for the tooth movement and the anchorage control, not depending only on the mechanical stress should be established.1. Trying to suppress the relapse of the tooth after experimental tooth movement, we locally injected 1,25(OH)_2D_3 or TGF-β in the pressure side of the alveolar bone. 1,25(OH)_2D_3, injected group had no effect on the relapse. On the other hand, 24,25(OH)_2D_3 or TGF-β delivered group suppressed the tooth relapse showing few osteoclasts, but active bone formation by osteoblasts. Furthermore, in these groups the bone volume and bone formation surface in the pressure side increased, and resorption surface and the number of osteoclasts decreased.2. HVJ liposome method is developed an efficient and … More nontoxic in vivo gene transfer compared to adenoviral vector-mediated gene delivery. Following experiments were performed to examine the optimum conditions of HVJ lipoeome method for experimental tooth movement model in rats.(1) Luciferase gene was delivered to mesenchymal cells, isolated from bone marrow in mouse femur, by using HVJ-liposome method in vitro. Luciferase reporter assay was performed to evaluate delivery rate.(2) During experimental tooth movement in rats, β-galactoeidase gene (LacZ) was delivered to the maxillae by using HVJ-liposome method. Three days after gene introduction, X-gal staining was performed to evaluate the deliveryate. These studies indicated that the gene delivery by using HVJ-liposome was efficient to the experimental tooth movement.3. Experimental tooth movement was performed after CTGF gene was delivered by using HVJ-liposome in rat. After 1,3,5,7 and 15 days of tooth movement, the maxillary bones were dissected. In situ hybridization and immunohistochtemistry were performed to analyze the expression of CTGF in periodontal tissue. Less