Grassia V, d'Apuzzo F, DiStasio D, Jamilian A, Lucchese A, Perillo L
Multidisciplinary Department of Medical-Surgical and Dental Specialties, Second University of Naples, Naples, Italy.
Department of Orthodontics, Center of Craniofacial Research, Islamic Azad University, Tehran, Iran.
Eur J Paediatr Dent. 2014 Dec;15(4):375-80.
The aim of this study was to evaluate upper and lower dental changes after Mixed Palatal Expansion (MPE) treatment in growing patients with posterior single or bilateral crossbite and mild-to-moderate crowding, as compared to untreated growing subjects by dental cast analysis.
A group of 24 patients (18 girls, 6 boys) was treated with Hyrax-type device and compared with an untreated matched control group at T0 (8.6 yrs. ± 2) and at T1 (10 yrs. ± 2) using dental casts. The dental cast analysis was performed on four dental bilateral landmarks, on upper and lower casts; also upper and lower arch depths were measured. The groups were compared using independent sample t-test to estimate dental changes in upper and lower arches.
The MPE group showed significant upper and lower arch changes when compared with the control group. Upper intermolar, interpremolar-2nd, interpremolar-1st (P<0.001) and intercanine widths (P<0.05) showed considerable changes in the treated group, while mandibular intermolar (P<0.001), interpremolar-1st (P<0.05) and intercanine widths (P<0.01) were slightly greater in the MPE group when compared with the control group.
The changes in transverse upper and lower arch dimensions were significant, when compared with those seen in the control group.
本研究旨在通过模型分析，评估在生长发育期的后牙单侧或双侧反合及轻至中度牙列拥挤患者中，采用混合腭扩展（MPE）治疗后上下牙列的变化，并与未治疗的生长发育期受试者进行比较。
选取24例患者（18名女孩，6名男孩），使用Hyrax型矫治器进行治疗，并在T0（8.6岁±2岁）和T1（10岁±2岁）时，使用模型与未治疗的匹配对照组进行比较。对上下颌模型上的四个双侧牙颌标志点进行模型分析；同时测量上下颌牙弓深度。采用独立样本t检验对两组进行比较，以评估上下颌牙弓的变化。
与对照组相比，MPE组上下颌牙弓有显著变化。治疗组上颌磨牙间、第二前磨牙间、第一前磨牙间（P<0.001）和尖牙间宽度（P<0.05）有明显变化，而MPE组下颌磨牙间（P<0.001）、第一前磨牙间（P<0.05）和尖牙间宽度与对照组相比略有增加（P<0.01）。
与对照组相比，上下颌牙弓横向尺寸的变化显著。
