Abstract: Objective: To study the effect of skeletal anchorage class III intermaxillary elastic distraction system on hard tissue and temporomandibular joint structure of skeletal Class III malocclusions patients. Methods: Forty skeletal class III malocclusion patients who needed protraction treatment were recruited for the study. Patients were assigned into experimental group and control group in accordance with their choice after explain the treatment plan. In the experimental group, after rapid maxillary expansion, implants were inserted to bilateral zygomatic ridge and tightly ligated with rapid maxillary expansion to form a rigid structure. A splint was bonded in mandibular arch for 24 hours and class III intermaxillary elastic (3.5OZ/side) distraction was performed between implant and splint. In the control group, after rapid maxillary expansion, traditional protraction facemask was used with 500g/side. The average course of treatment was 9 months. Cephalometric analysis before and after treatment was used to evaluate the changes of hard tissues of patients. CBCT examination before and after treatment was used to analyze the change of temporomandibular joint. Results: Class III malocclusion was improved in all patients. Profile changed from concave to straight. Anterior teeth became normal overbite and overjet. Upper and lower anterior teeth axis inclination had no obvious change, maxillary growth forward, point A moved forward; SNA and ANB increased; SNB had no obvious change; mandibular angle increased with clockwise rotation. The morphological structure of the temporomandibular joint was good. And the anterior, superior, posterior, lateral and medial temporomandibular joint spaces had no change before and after treatment. Compared with the control group, maxilla of the experiment group had no rotation and upper incisors had no obvious labial inclination, but lower incisors appeared obvious lingual



基金项目 佛山市医学类科技攻关项目(编号:2014AB00389)
佛山市科技创新专项资金(编号:2015AG10015)
作者简介 艾毅龙(1976~ ),男,江西人,学士,主治医师,主 要从事口腔正畸临床与科研工作。
*通讯作者 王增全,E-mail:420064165@qq.com
tipping. Conclusion: Skeletal anchorage class III intermaxillary elastic distraction system can improve the growth of nasomaxillary complex and had no adverse effect on the temporomandibular joint.

Key words: Skeletal class III malocclusion , Protraction, Intermaxillary elastic