应用正畸移动装置在牵引成骨新成骨中移动牙的动物模型的建立

目的探讨应用自制正畸移动装置在牵引成骨新成骨中移动牙的方法的可行性，建立动物模型，为临床应用提供客观理论依据。方法将六只成年（12～15月龄）雄性小尾寒羊（绵羊）的下颌两侧随机分组，随机选择一侧为实验组，另一侧为对照组。实验组按照骨成熟期分为一周组、两周组、三周组、四周组（非成熟骨组）和半年组、一年组（成熟骨组）。对照组分为常规对照和空白对照。非成熟组对侧为常规对照，成熟骨组对侧为空白对照。实验组在下颌第一双尖牙的近中牙槽嵴位置行手术骨皮质切开，放置牵引成骨器，术后5天开始牵引成骨，每12小时牵引加力一次，1．2mm／d，牵引6天，在第一双尖牙近中形成7．2mm新生骨段；分别在一周、两周、三周、四周和半年、一年后，在第一双尖牙近中约2cm位置牙槽嵴顶植入种植钉作为支抗，使用正畸轻力移动牙齿的方法应用镍钛拉簧牵引第一双尖牙向近中移动，力值约100g（0．98N），3周后第一双尖牙移入牵引成骨骨段。常规对照组，使用同样正畸方法牵引第一双尖牙向近中移动3周。结果实验组牙齿顺利移动进入牵引成骨骨段，松动度Ⅰ度，局部牙龈红肿、轻度炎症，X线检查示无X尖周病变、无明显牙根吸收。结论使用正畸力在牵引成骨新成骨中移动牙齿的方法切实可行，本研究所建立的动物模型可以应用于后续的研究中。

Experimental tooth movement through bone regenerated after distraction osteogenesis in sheep

Objective To establish animal model of orthodontic tooth movement through bone regenerated after distraction osteogenesis .Methods The experiment was carried out in 6 adult male sheep, with one side of jaws served as experiment or control side.Experimental groups were randomly divided into one-week group、two-week group、three-week group、four-week group (immature group) and half year group、 one year group (mature group).Control groups were divided into conventional control group and blank group.Immature group had conventional control and mature group had blank control.In experimental groups, 7mm of mandibular distraction osteogenesis was created.After one week,two week, three week, four week half year and one year consolidation periods, first premolar was moved mesially into the regenerated bone with l00g of orthodontic force for 3 weeks.In conventional control group, the same method was used for tooth movement Clinical and X-ray examination, were carried out.Results All the teeth in experimental groups were moved into the regenerate bone well.No apparent root resorption was found.Conclusions Orthodontic tooth movement through bone regenerated after distraction osteogenesis was possible.