Siqueira Danilo Furquim, de Almeira Renato Rodrigues, Janson Guilherme, Brandão Analu Giampietro, Coelho Filho Carlos Martins
Department of Orthodontics, Bauru Dental School, University of São Paulo, Bauru, São Paulo, Brazil.
Am J Orthod Dentofacial Orthop. 2007 Apr;131(4):447.e21-30. doi: 10.1016/j.ajodo.2006.04.029.
In this study, we cephalometrically compared changes in the dentoskeletal and soft tissues after orthodontic treatment of Class II Division 1 malocclusions between the cervical headgear (CHG) and the mandibular protraction appliance (MPA) followed by fixed appliances.
The sample consisted of 50 patients divided into 2 groups of 25 patients each (13 male, 12 female). Group 1 patients were treated with CHG and fixed appliance, and group 2 patients were treated with the MPA and fixed appliances. The patients were matched according to sex, age, treatment time, and initial cephalometric variables. The groups were compared regarding pretreatment stage and treatment changes, with t tests, at P <.05.
The CHG group showed statistically greater restriction of the anterior displacement of the maxilla, improvement of the skeletal Class II relationship, decreased facial convexity, extrusion and distalization of the maxillary first molar, and extrusion of the mandibular incisors. The MPA group had statistically greater increases in maxillary length, mandibular protrusion, maxillary incisor retrusion, mesial displacement of the mandibular first molars, and protrusion of the lower lip.
The changes in Class II malocclusion correction between the CHG and the MPA were that the CHG corrected the Class II malocclusion primarily through greater action on the maxillary skeletal and dentoalveolar structures as compared with the MPA, which corrected the malocclusion through greater action on the mandibular dentoalveolar structures.
在本研究中，我们采用头影测量法比较了使用颈带矫治器（CHG）和下颌前伸矫治器（MPA）矫治安氏II类1分类错牙合畸形后，继以固定矫治器治疗，牙颌面及软组织的变化情况。
样本包括50例患者，分为两组，每组25例（男性13例，女性12例）。第1组患者采用CHG和固定矫治器治疗，第2组患者采用MPA和固定矫治器治疗。根据性别、年龄、治疗时间和初始头影测量变量对患者进行匹配。采用t检验对两组在治疗前阶段和治疗变化方面进行比较，P<0.05为有统计学意义。
CHG组在统计学上显示出对上颌前移的限制更大、骨性II类关系改善、面部凸度减小、上颌第一磨牙伸长及远中移动，以及下颌切牙伸长。MPA组在统计学上显示上颌长度增加、下颌前突、上颌切牙后缩、下颌第一磨牙近中移动及下唇前突更为明显。
CHG和MPA在矫治II类错牙合畸形方面的变化在于，与MPA相比，CHG主要通过对上颌骨骼及牙槽结构的更大作用来矫治II类错牙合畸形，而MPA则通过对下颌牙槽结构的更大作用来矫治错牙合畸形。
