β-磷酸三钙复合自体骨髓修复兔牙槽骨缺损区牙齿移动的实验研究

Orthodontic tooth movement in alveolar bone defects repaired with β-TCP/bone marrow:an experimental study in rabbits

目的:对比观察在正畸力作用下,牙齿在β-磷酸三钙(β-TCP)复合自体骨髓和单纯β-TCP修复后的牙槽骨缺损区的移动情况。方法:选择新西兰大白兔6只,拔除双侧下颌第一磨牙,扩大牙槽窝,建立牙槽骨缺损实验动物模型。采用自身左右对照设计,采用完全随机化分组将一侧分为实验组,采用β-TCP复合自体骨髓修复牙槽骨缺损,另一侧为对照组,单纯使用β-TCP修复牙槽骨缺损。两组均覆盖BME-10X胶原膜。术后12周,以下前牙作支抗,每侧加力80 g,牵引双侧下颌第二磨牙向近中移动,加力8周后处死,测量牙齿移动距离,并通过影像学和组织学切片观察对比分析两组牙齿移动区域牙槽骨等牙周组织的变化。结果:术后12周,施以正畸力,第二磨牙可以在实验组和对照组牙槽骨缺损修复区正常移动。实验组移动距离为(1. 99±0. 11) mm,对照组移动距离为(2. 80±0. 19) mm,差异有统计学意义(P <0. 05)。结论:在正畸力作用下,牙齿可以在牙槽骨缺损修复区正常移动。

Objective：Observed under orthodontic force,the tooth in theβ-TCP alone or in combination with bone marrowsituation after repair of alveolar bone defect area. Methods：Six New Zealand rabbits were used. The first mandibular molars on each side were removed. The extraction sockets were expanded bilaterally to establish the experimental animal mod- el of alveolar bone defects and randomly filled by β-TCP combined with bone marrow on one side（ test group）, and β-TCP a- lone on the other side（ control group）. All the defects were covered with a resorbable membrane（ BME- 10X）. Twelve weeks after operation, by using the mandibular incisor as anchorage, orthodontic tooth movement was initiated 8 weeks to allow mesi- al movement of the 2 nd mandibular molars for the remaining rabbits. The applied force was 80 g. Then, all the rabbits were sacrificed for radiographic and histological analysis and the tooth movement distance was measured. Results：At 12 weeks af- ter surgery, the orthodontic force was applied and the second molars were able to move normally in the repair area of the alve- olar bone defects in the experimental group and the control group. The moving distance of the experimental group was （ 1.99 ± 0. 11 ） mm, and the moving distance of the control group was （ 2. 80 ± 0. 19 ） mm. There was statistically significant difference between two groups （P 〈 0. 05 ）. Conclusion：The osteogenic effectiveness of β-TCP/bone marrow for alveolar bone defects is better than β-TCP alone and bone marrow can enhance the new bone formation.