摘要
目的:通过牙支持式牵引装置配合牙槽手术建立快速整体内收上颌前牙及前颌骨的动物模型,研究其可行性.方法:成年比格犬6只,拔除上颌双侧尖牙,实施减阻-牵引措施,术后即刻加载0.5 mm/d,连续加力12 d;并分别于加力停止后,固定4 wk后静脉空气栓塞处死各3只.所有实验动物均于加力前、处死前拍摄X光头影测量片及根尖片,并进行标本测量.结果:前牙整体后退4.54 mm,后牙支抗丧失1.31mm,上颌前牙顺时针旋转3.40°,上颌前颌骨缩短1.34 mm,但上颌骨内收量各犬之间变异很大,且未见明显牙根吸收、牙齿松动、骨坏死等不良并发症.结论:采用牙槽外科辅助的方法可达到快速整体内收上颌前牙的目的,但对上颌前颌骨内收的影响不大.
Abstract
AIM: To investigate whether whole anterior maxillary teeth and premaxillary could be distracted rapidly aided by alveolar surgery. METHODS: Bilatery maxillary canines were extracted and anterior maxillary osteotomy was performed in 6 beagles. After cementing the routine tooth-borne appliance,the distraction device was force loaded by 0. 5 mm/d to retract the whole anterior maxillary teeth for 12 d. Three animals were executed immediately after distraction was completed and the other 3 were executed 4 weeks after the fixture. Cephalometric and periapical films were taken before force loading and execution. RESULTS: Tooth and radiograph measurement indicated that the anterior teeth moved 4.54 mm on average and the posterior teeth moved 1.31 mm. The anterior teeth rotated 3.4 degree clockwise. The average skeleton movement was 1.34 mm,but there were big variations between dogs. No apparent complications such as root resorption,loosening of tooth or bone necrosis occurred. CONCLUSION: Alveolar surgery can increase the orthodontic tooth movement of whole anterior teeth,but it has no apparent effect on premaxillary.
基金项目
广东省医学科学研究基金(A2006103)
广东省自然科学基金(8151026003000008)