快速扩缩弓并前牵引矫治恒牙早期安氏Ⅲ类错的疗效

Clinical evaluation on maxillary protraction combined with rapid maxillary expansion and constriction in treating Class Ⅲ malocclusion in early permanent dentition by Pitchfork analysis

目的研究上颌前方牵引联合快速扩缩弓治疗恒牙早期安氏Ⅲ类错的骨性及牙性疗效。方法选取10例恒牙早期安氏Ⅲ类错患者,观察6个月作为观察对照期,随后应用前方牵引联合快速扩缩弓矫治6个月为治疗期,应用Pitchfork分析法比较对照期和治疗期在平均功能性平面上骨骼及牙齿的位置变化。结果磨牙关系改变了7.2 mm(t=6.85,P<0.05),包括骨性改变4.4 mm、牙性改变2.8 mm;骨性改变中上下颌骨贡献率约为1∶3,牙性改变中上下磨牙贡献率约为2∶3。结论前方牵引联合快速扩缩弓可有效治疗恒牙早期安氏Ⅲ类错,可取得较大的牙关系改善。

Objective To evaluate the skeletal and dental contribution rate to the treatment effects of maxillary protraction combined with rapid maxillary expansion and constriction on patients with Class Ill malocclusion in early permanent dentition. Methods Ten Class Ⅲ patients in early permanent dentition were observed for 6 months and then treated by maxillary protraction combined with rapid maxillary expansion and constriction for another 6 months. Pitchfork analysis was performed to evaluate the skeletal and dental changes between these two periods. Results The treatment made 7.2 mm （t= 6.85,P〈0.05） molar correction in general, which included 4.4 mm skeletal change and 2.8 mm dental change. Within the skeletal change, the contribution ratio of upper and lower jaw was about 1 ： 3. Within the dental change, the contribution ratio of upper and lower molar was about 2 ： 3. Conclusion This study demonstrated that maxillary protraction combined with rapid maxillary expansion and constriction therapy could produce great occlusion improvement for the Class Ⅲ patients in early permanent dentition.