微手术正畸治疗骨性Ⅲ类错伴下前牙区牙槽骨发育不良的效果评价

Exploration for micro-osteotomy assisted orthodontic treatment of skeletal Class Ⅲ malocclusions with alveolar hypoplasia in the lower anterior region

目的:探讨微手术正畸对骨性Ⅲ类错伴下前牙牙槽骨发育不良的术前去代偿正畸临床策略,检查矫正后下前牙槽骨和牙周组织健康状况的改善程度,提出临床对策,治疗牙槽骨发育不良。方法:从2009—2012间于上海交通大学附属第九人民医院口腔颅颌面科求治的成人连续病例中,选取下前牙区牙槽骨发育不良且有正颌手术适应证的骨性Ⅲ类错畸形为研究对象,按照是否接受微手术正畸治疗进一步分为2组。10例接受者纳入微手术组(G1组),12例不接受者纳入对照组(G2组)。通过锥形束CT(cone beam computed tomography,CBCT)测量2组术前正畸前、后左侧中、侧切牙牙根长度,唇舌侧牙槽骨高度及厚度。采用SAS 8.02软件包对数据进行统计学处理。结果:G1组术前正畸结束,唇侧牙槽骨高度降低2.60 mm,舌侧降低2.22 mm;根尖唇侧厚度增加3.05 mm,舌侧减小0.88 mm,根尖水平总牙槽骨厚度增加2.13 mm,与G2组有显著差异。较之G2组,更好地控制了术前正畸去代偿过程中下前牙牙根的吸收及牙槽骨高度、厚度的丧失。结论:微手术正畸用于下前牙区牙槽骨发育不良的骨性Ⅲ类错术前去代偿,能够有效降低治疗过程中牙周破坏(牙根吸收、牙槽骨吸收、穿孔等)的风险,克服下颌牙槽骨对去代偿竖直牙的限制,提高此类患者术前正畸的安全性。

PURPOSE： To investigate the changes of periodontal conditions after micro-osteotomy assisted lower incisor decompensation for skeletal Class Ⅲ malocclusions with alveolar hypoplasia in the lower anterior region.METHODS： The sample consisted of 22 cases diagnosed as skeletal Class Ⅲ malocclusions with alveolar hypoplasia in the lower anterior region,selected from consecutive patients of Department of Oral Cranio-maxillofacial Science of Shanghai Ninth People＇s Hospital during 2009-2012.The samples were divided into 2 groups,G1 comprised 10 patients who accepted micro-osteotomy assisted lower incisor decompensation;G2 comprised 12 patients who chose traditional presurgical decomposition.The changes of periodontal conditions of both groups were evaluated with the help of cone-beam CT（CBCT）.Data was processed using SAS8.02 software package.RESULTS： For subjects in G1,during the microosteotomy assisted pre-surgical orthodontics,no significant difference was found in the amount of root resorption of lower incisors.But labial and lingual vertical alveolar bone loss were 2.60 mm and 2.22 mm;alveolar bone thickness increased by 3.05 mm on the labial side and decreased by 0.88 mm on the lingual side（P0.05）.Better periodontal conditions were reserved compared with those of G2.CONCLUSIONS： Micro-osteotomy assisted pre-surgical orthodontics was much safer than traditional orthodontics for skeletal Class Ⅲ malocclusions with alveolar hypoplasia in the lower anterior region.