摘要目的 本研究对51例接受正畸正颌联合治疗的骨性Ⅲ类错(牙合)患者,其治疗前后及治疗中的X线头颅侧位片进行分析计算,探究切牙角度及软组织侧貌在各治疗阶段的变化,分析拔牙设计对疗效的影响.方法 选取进行正畸正颌联合治疗的成年骨性Ⅲ类错(牙合)患者51例,根据上颌拔牙与否分为两组,拔牙组:上颌两侧分别拔除一颗前磨牙,21例;非拔牙组:上颌未拔牙,30例.取治疗前(T0)、正颌术前一月(T1)、治疗后(T2)三个阶段的头颅侧位片,选择骨性指标9项,牙性指标10项,软组织指标15项,使用SPSS 19.0进行头影测量分析.结果 拔牙组及非拔牙组的骨性Ⅲ类错(牙合)患者术前颅颌面形态无明显差异,但采用拔牙术前去代偿的患者的上前牙唇倾度、切端突度在术前正畸减小更明显(U1-NA/°减小4.38°,U1-NA/mm减小2 mm),而非拔牙组术前去代偿中上前牙唇倾度和突度变化不明显;两组下颌切牙均去代偿明显(L1-NB/°分别增大12.4°和9.52°),下唇厚度均变薄.拔牙组治疗完成后上下唇突位置均较非拔牙组更靠后,其ANB角术前术后变化更明显.结论 颅面骨形态相似的骨性Ⅲ类错(牙合)畸形患者,正畸正颌联合治疗术前正畸采用上颌拔牙去代偿,其术前上颌去代偿会更充分,可能更有利于正颌手术改善Ⅲ类骨面型的软硬组织形态.

abstractsObjective To investigate the changes in incisor inclination and soft tissue profile before and after surgical-orthodontic treatment and the effect of extraction treatment planning on the curative effect of skeletal class Ⅲ patients.Methods The subjects consisted of 51 skeletal Class Ⅲ patients treated with the surgical-orthodontic approach.They were divided into 2 groups:extraction group (n=21) had an extraction of the maxillary premolars,and non-extraction group (n=30) had no extractions.Lateral cephalograms were analyzed before treatment (T0),1 month before surgery (T1),and after debonding (T2).9 items of hard tissue indexes,10 items of dental indexes and 15 items soft tissue indexes were selected.After the measurement of variables,SPSS 19.0 was used to analyze and compare the data.Results The cephalogram analyses showed that there was no obvious difference between extraction group and non-extraction group before treatment.In pre-operation treatment,maxillary incisors' decompensation and the decrease of protrusion were more obvious in the extraction group (U1-NA/° reduced by 4.38°,U1-NA/mm reduced by 2 mm);conversely,there was an increasing trend of compensation of maxillary incisors in the non-extraction group.The mandibular incisors in both groups were significantly decompensated(L1-NB / ° increase of 12.4 ° and 9.52 °respectively) and the lower lip thickness was thinner.After treatment,the position of upper and lower lip in the extraction group were more posterior than those in the non-extraction group,and the changes of ANB Angle were more obvious after surgery.Conclusions For skeletal Class Ⅲ patients with similar craniofacial features,pre-surgery extraction decompensates incisor inclination better,which may results in greater improvement of soft and hard tissue morphology after orthognathic surgery.