拔牙创愈合对正畸牙移动的影响

目的 比较尖牙在不同愈合期的拔牙区内移动后根尖的吸收情况和牙槽骨高度的变化，为临床上选择拔牙区内正畸牙移动的最佳时机提供参考。方法 选取20例需拔除上颌双侧第一前磨牙矫治的错畸形患者的40颗上颌尖牙为研究对象，在拔除上颌第一前磨牙后1周和12周开始随机牵引上颌不同侧尖牙向远中移动，至尖牙与上颌第二前磨牙接触后，拍摄尖牙的根尖定位片，测量尖牙根尖吸收等级和牙槽骨水平高度。结果 在拔除上颌第一前磨牙后1周和12周移动上颌尖牙，尖牙的根尖吸收情况和牙槽骨水平高度没有统计学差异（P>0.05）。结论 拔牙创的愈合对移动牙齿的根尖吸收和牙槽骨水平高度没有明显影响，可以考虑拔牙后早期移动牙齿。

Changes of Orthodontic Tooth in Different Healing Extraction Sites

Objective To compare the canines root resorption and alveolar bone height when they were moved into different healing extraction sites. Methods Twenty patients with overjet were treated by extracting the maxillary first premolars. By random determination, distalization of different lateral upper canines started after 1 week and 12 weeks. Every 4 weeks use a force of approximately 100 g to distalize the canines. The experiment was ended when bilateral canines have contacted with the second maxillary bicuspids completely. Periapical radiography of the canine in the end of the distalization was made. Results External apical root resorption and alveolar bone height of the canines have no significant difference between the different healing extraction sites. Conclusion Tooth extraction site healing has not much effect on the canine external apical root resorption and alveolar bone height, when it was distalization. In practice, tooth movement into extraction sites can start early.