Bravo L A, Canut J A, Pascual A, Bravo B
Orthodontic Unit, School of Medicine, University of Murcia, Spain.
Br J Orthod. 1997 Feb;24(1):25-34. doi: 10.1093/ortho/24.1.25.
A study was made of 31 patients with Angle Class II malocclusion. Fifteen patients did not undergo extraction of teeth (Group A), while 16 underwent extractions of four premolars (Group B). Data was obtained from the corresponding lateral radiographs of the head taken both before and after orthodontic treatment. The main aim of the study was to compare the response of the soft and hard tissues of the facial profile in Class II malocclusion treated with the extraction of four premolars and the response of borderline cases presenting with similar malocclusions, but not subjected to extraction. In this latter group reasonable doubt existed as to whether or not to remove teeth in order to solve the occlusal and aesthetic problems. It is concluded that significant hard tissue differences between the groups at the end of treatment were limited to a more retruded position of the incisors and a reduced overbite amongst those patients subjected to extraction. The main soft tissue differences between the groups at the end of treatment were a more retruded lower lip and a more pronounced lower labial sulcus in those patients subjected to extraction.
对31例安氏II类错牙合患者进行了研究。15例患者未拔牙（A组），而16例患者拔除了四颗前磨牙（B组）。从正畸治疗前后拍摄的相应头颅侧位片获取数据。该研究的主要目的是比较拔除四颗前磨牙治疗的II类错牙合患者面部软硬组织的反应，以及存在相似错牙合但未拔牙的临界病例的反应。在后一组中，对于是否拔牙以解决咬合和美观问题存在合理疑问。得出的结论是，治疗结束时两组之间的显著硬组织差异仅限于拔牙患者中切牙位置更后缩和覆牙合减小。治疗结束时两组之间主要的软组织差异是拔牙患者下唇更后缩和下唇唇沟更明显。
