锥形束CT观察无托槽隐形矫治儿童安氏Ⅱ类2分类错合牙颞下颌关节形态变化研究

CBCT observation on morphological changes of temporomandibular joint in children with class Ⅱ division 2 malocclusion treated by bone anchorage swing appliance

摘要:

目的 通过锥形束CT（CBCT）观察无托槽隐形矫治器矫治儿童安氏Ⅱ类2分类错颞下颌关节形态的变化。方法 选取2016年1月—2020年10月南昌市第三医院收治的82例安氏Ⅱ类2分类错患儿作为研究对象，按照不同的矫治器分为对照组和研究组，每组41例。对照组采用自锁托槽矫治器，研究组采用无托槽隐形矫治器。两组患儿矫治前后通过CBCT观察颞下颌关节相关角度、面高、关节间隙及髁突变化情况。结果 两组患儿矫治前后上牙槽座角（SNA）、下牙槽座角（SNB）、上下牙槽座角（ANB）、下颌平面角（MP-FH）、蝶鞍中心与颏顶连线与眼耳平面相交的下前角（Y轴角）、全面高（N-Me）、上面高（N-ANS）、下面高（ANS-Me）差值的比较，差异均无统计学意义（P >0.05）；研究组矫治前后上中切牙长轴与前颅底（SN）平面相交的下内角（U1-SN）、上中切牙长轴与鼻根点-上牙槽座点连线交角（U1-NA）的差值均高于对照组（P <0.05）；两组矫治前后关节上间隙、前间隙、后间隙及髁突高度、髁突内外径、髁突前后径差值的比较，差异均无统计学意义（P >0.05）。结论 无托槽隐形矫治器、自锁托槽矫治器用于安氏Ⅱ类2分类错颞下颌关节，相关参数有一定变化，髁突有向前移动趋势，无托槽隐形矫治器比自锁托槽矫治器更适用于安氏Ⅱ类2分类错患儿，可在相同矫治时间内获取更佳的矫治效果。

Abstract:

Objective To observe the morphological changes of temporomandibular joint in children with Angel's class Ⅱ classification 2 malocclusion with Cone beam computed tomography (CBCT).Methods A total of 82 children with Class Ⅱ and 2 classifications were selected from January 2016 to October 2020 in our hospital. They were divided into control and study groups by random number table, with 41 cases in each group. The control group was treated with self-locking brackets, and the study group was treated with bracketless invisible aligners. CBCT was used to measure the relative angle, face height, joint space, and condyle mutation of the temporomandibular joint before and after treatment in the two groups.Results There was no statistically significant difference in the upper alveolar seat angle (SNA), lower alveolar seat angle (SNB), upper and lower alveolar seat angle (ANB), mandibular plane angle (MP-FH) lower front angle (Y-axis angle), the overall height (N-Me), the upper height (N-ANS), and the lower height (ANS-Me) difference before and after treatment between the two groups (P > 0.05). The difference values of the lower inner angle of the intersection between the long axis of the upper central incisor and SN plane (U1-Sn) and the intersection angle between the long axis of the upper central incisor and the root of the nose and the upper alveolar seat (U1-NA) in the study group were higher than those in the control group before and after treatment (P < 0.05). There were no significant differences in suprarticular space, anterior space, posterior space, condyle height, internal and external diameter, and anterior and posterior diameter between the two groups before and after treatment (P > 0.05).Conclusion Bracketless invisible aligners and self-locking bracket appliances were used in children with Class Ⅱ and Class Ⅱ malocclusion with certain changes in temporomandibular joint parameters, and the condyles tended to move forward. The locking bracket appliance is more suitable for children with angelic Class Ⅱ and Class Ⅱ malocclusion, and can obtain better orthodontic effect within the same orthodontic time.