弹性包绕式垫加前方牵引矫治替牙期骨性反

Treating skeletal anterior crossbite patients with maxillary protraction Combined with elastic wrapping bite guard in the mixed dentition

目的探讨弹性包绕式垫加前方牵引矫治替牙期骨性反的适用性及治疗前后的牙颌结构变化。方法选择替牙期骨性Ⅲ类错患者9例,平均年龄8.1±1.5岁,患者前牙反,上颌相对于下颌后缩,应用弹性树脂材料制作包绕上颌全部牙齿及部分牙槽骨的包绕式垫,中部连接螺旋扩弓器快速扩弓,加前方牵引矫治反。在头颅侧位片上测量矫治前后牙、牙槽骨及颌骨的变化。结果弹性包绕式垫固位良好,腭中缝在2～3周内打开,前牙反在6～11个月内解除;上颌骨前移,下颌骨轻度向下后旋转,SNA平均增大1.9°,ANB角平均增大2.8°;治疗后上切牙唇倾,下切牙舌倾。结论在替牙期采用弹性包绕式垫加前方牵引能够促进上颌骨生长,简便、有效地治疗替牙期骨性反。

Objective To evaluate the changes in skeletal anterior crossbite patients after maxillary protraction combined with elastic wrapping bite guards in the mixed dentition. Methods Nine skeletal anterior crossbite patients with mean age being 8.1 ± 1.5 years were selected. The malocclusions of the patients included anterior crossbite and underdeveloped maxilla. Anterior crossbite were treated with maxillary protraction and the bite guards made of elastic resin. Cephalometric radiographs were taken before and after treatment. Cephalometric analysis was used to examine the dental and skeletal changes. Results There was enough retentive force with the elastic wrapping bite guard. The skeletal changes consisted of maxillary anterior displacement and mandibular downward and backward rotation. SNA increased 1.9°, ANB increased 2.8°. Dental alterations comprised a tendency of labial tipping of the maxillary incisors and lingual tipping of the mandibular incisors. Conclusion Maxillary protraction combined with elastic wrapping bite guard in the mixed dentition is effective in the correction of skeletal anterior erossbite and it can induce more pronounced transverse eraniofaeial changes at the skeletal level.