青少年正畸上颌切牙不同内收方式对牙槽骨形态的影响

Effect of different adduction methods of maxillary incisor in adolescents on the shape of alveolar bone

目的 :探讨青少年正畸上颌切牙不同内收方式对牙槽骨形态的影响。方法 :收集2018年6月—2019年6月福建医科大学附属协和医院收治的颌骨前突畸形82例患者的328颗上颌切牙,135颗切牙纳入倾斜内收组,193颗切牙纳入控根内收组。拍摄锥形束CT(CBCT),测量患者上颌切牙内收情况及牙槽骨高度、厚度、骨密度变化。采用SPSS 18.0软件包对数据进行统计学分析。结果:倾斜内收组治疗后上颌切牙切缘至腭中垂面长度(IE-MP)、上颌切牙长轴与腭平面后下角(LAI-PP)变化值显著大于控根内收组(P<0.05),倾斜内收组上颌切牙根尖至腭中垂面长度(RA-MP)变化值显著小于控根内收组(P<0.05)。倾斜内收组治疗后L1、L2、L3、P1、T1显著低于治疗前(P<0.05),治疗后P2、P3、T2、T3显著高于治疗前(P<0.05);控根内收组治疗后L1、L2、L3显著高于治疗前(P<0.05),治疗后P1、P2、P3、T1、T2、T3显著低于治疗前(P<0.05);倾斜内收组治疗前、治疗后的L2、L3、P3、T3变化量显著高于控根内收组(P<0.05),倾斜内收组治疗前、治疗后的L1、P1、P2、T1、T2变化量显著低于控根内收组(P<0.05)。2组治疗前、治疗后6个月的上、下颌牙槽骨骨密度相比,差异无统计学意义(P>0.05)。结论:青少年上颌切牙大范围内收时,倾斜内收组唇侧根尖区、腭侧牙槽嵴区及控根内收组腭侧牙根颈部均为牙槽骨吸收高风险区。

PURPOSE: To explore the influence of different adduction methods of maxillary incisor in adolescents on the shape of alveolar bone. METHODS: Three hundred and twenty-eight maxillary incisors were collected from 82 patients with jaw protrusion deformity treated in Union Hospital of Fujian Medical University from June 2018 to June 2019. 135incisors were included in the oblique adduction group, and 193 incisors were included in the root control adduction group.All patients took cone-beam CT(CBCT) to measure the adduction of the maxillary incisor and the changes in alveolar bone height, thickness, and bone density. Statistical analysis was performed with SPSS 18.0 software package. RESULTS: The length of the maxillary incisor to the mid-palatine vertical surface(IE-MP), the long axis of the maxillary incisor and the posterior inferior angle of the palatal plane(LAI-PP) in oblique adduction group were significantly greater than root control adduction group(P<0.05). The length of the maxillary incisor from the apex of the maxillary incisor to the mid-palatine vertical surface(RA-MP) in the oblique adduction group was significantly smaller than the root control adduction group( P<0.05). Postoperative L1, L2, L3, P1, T1 of the oblique adduction group were significantly lower than preoperative values( P<0.05), and postoperative P2, P3, T2, and T3 were significantly higher than preoperative value(P<0.05). Postoperative L1,L2, and L3 of the root control adduction group were significantly higher than those before operation(P<0.05), and postoperative P1, P2, P3, T1, T2, and T3 were significantly lower than those before operation(P<0.05). The changes of L2, L3,P3, T3 of the oblique adduction group were significantly higher than the control root adduction group(P<0.05), and the changes of L1, P1, P2, T1, T2 of the oblique adduction group were all significantly lower than the control root adduction group(P<0.05). There was no significant difference in bone mineral density of the upper and lower jaws between the two groups before and 6 months after operation(P>0.05). CONCLUSIONS: When adolescents’ maxillary incisors are retracted in a wide range, the labial apical area, the palatal alveolar ridge area of the oblique adduction group, and the palatal root neck of the root control adduction group are all high-risk areas for alveolar bone resorption.