双颌前突畸形正畸治疗后颅面硬组织变化的研究

Changes of Cranio-facial Hard Tissue after Orthodontic Treatment in Bimaxillary Protrusive Patients

目的 研究正畸治疗对双颌前突患者硬组织矢状及垂直向的影响。方法 对24例广东籍双颌前突患者在拔除4个第一双尖牙后,采用标准方丝弓矫治技术进行矫治,并对矫治前后硬组织侧貌的变化进行分析。结果 ①上下颌骨问关系无明显变化,上下前牙突度和倾斜度明显减小。②前后面高明显增加,但前后面高间的比值及反映下颌平面倾斜度的MP-FH无明显变化。③上下磨牙高度随前后面高的增加而明显增加。④上前牙高度明显增加,下前牙高度明显减小。结论 双颌前突畸形正畸治疗中垂直向及矢状向支抗可得到较好控制。

Objective The aim of this study is to investigate the changes of hard tissue profile in anterior-posterior and vertical direction in bimaxillary protrusion patients after orthodontic treatment. Methods A total of 24 bimaxillary protrusion patients (male 8, female 16), aged from 11.2 to 29.0 (average 16.9 years old), were selected to be treated with standard edgewise technique consisted of 4 first premolars extraction. Cephalometrics were taken before and after treatment. The changes of hard tissue profile were studied using the computer-aid X-ray cephalometric analysis. Results 1 .The length of the maxillary and the mandible increased significantly, but the anterior-posterior relationship of the maxillary and the mandible did not change significantly. 2. The anterior and posterior facial height increased significantly, but the ratio of anterior and posterior facial height and the angle of MP-FH which reflected the inclination of the mandible plane did not change significantly. 3. The height of the upper and lower first molar increased significantly along with the increase of the anterior and posterior facial height. 4. The height of the upper incisors increased significantly, but the height of the lower incisors decreased significantly. Conclusion The anchorage in anterior-posterior and vertical direction were controlled preferably, the patients did not manifest disadvantageous vertical growth trend.