Aileni Kaladhar Reddy, Rachala Madhukar Reddy
Department of Orthodontics at S.V.S. Institute of Dental Sciences, Mahabubnagar, Andhrapradesh, India.
Int J Orthod Milwaukee. 2011 Winter;22(4):41-5.
Class III malocclusion with retrusive maxilla can be orthopedically corrected in the deciduous or mixed dentition, with reverse pull headgear in combination with or without rapid maxillary expansion. The advantage of expansion in these patients is to correct the posterior cross bite, and disarticulate the maxilla. This is a case report of successful treatment of developing skeletal class III malocclusion using Petit facemask without maxillary expansion. A 10-year-old girl presented with concave facial profile and decreased lower facial height. She had bilateral class III molar and canine relationships with reverse overjet of 3 mm and over bite of 6 mm. The treatment objective was to correct the skeletal class III to achieve a more harmonious facial profile. Patient was treated with Petit facemask, by applying a force directed at angle of 30 degrees to occlusal plane for a period of 4 months. The intra-oral appliance used was an acrylic cap splint without expansion. The post treatment results showed a significant improvement in facial profile with class I molar relationship and no change in treatment time when compared with patients treated by facemask therapy and maxillary expansion.
伴有上颌后缩的Ⅲ类错牙合畸形可在乳牙列或混合牙列期通过前方牵引矫治器结合或不结合快速上颌扩弓进行正畸矫治。对这些患者进行扩弓的优势在于纠正后牙反牙合,并使上颌骨分离。本文报告了一例使用Petit面罩矫治器成功治疗正在发展的骨性Ⅲ类错牙合畸形且未进行上颌扩弓的病例。一名10岁女孩,面部轮廓凹陷,面下1/3高度减小。双侧磨牙及尖牙呈Ⅲ类关系,反覆盖3mm,反覆牙合6mm。治疗目标是纠正骨性Ⅲ类错牙合,以获得更和谐的面部轮廓。对患者使用Petit面罩矫治器,以与牙合平面呈30度角的方向施加力,持续4个月。所使用的口内矫治器为无扩弓作用的丙烯酸帽状夹板。治疗结果显示,面部轮廓有显著改善,磨牙关系为Ⅰ类,与采用面罩疗法及上颌扩弓治疗的患者相比,治疗时间无变化。