Private practice, Teramo, Italy.
Department of Biomedical, Surgical and Dental Sciences, University of Milan, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy.
Eur J Paediatr Dent. 2019 Mar;20(1):38-42. doi: 10.23804/ejpd.2019.20.01.08.
The purpose of this study was to evaluate the effects of rapid maxillary expansion (RME) on maxillary and mandibular arch in the mixed dentition.
Forty-four consecutive patients with transverse maxillary deficiency were recruited. Test group: 21 patients (10 male, 11 female; 7.4 ± 1.2 years) who underwent RME (Haas type) therapy banded on the primary second molars.
17 patients (10 male, 7 female; 7.3 ± 1.1 years old) who did not receive any orthodontic treatment. Dental casts obtained pre-treatment and after appliance removal (11 months) were processed by means of a three-dimensional scanner (3Shape D250 laser, DK). Digital landmarks were traced using the VAM software (Canfield Scientific Inc., Fairfield-NJ, USA). Arch Length, interdental width and torque differences were measured before and after the removal of the appliance. The t-test (P<0.05) for paired data was applied to evaluate the measurements values before and after treatment. The linear regression model was employed to assess the correlations between treatment effects.
The efficacy of the RME was confirmed both on maxillary and mandibular arch. Mandibular intermolar width (+2.02 mm) together with primary intermolar (+1.39 mm), intercanine width (+0.95mm) and torque variations significantly increased. The untreated control group showed no significant statistical differences between T0 and T1. The linear regression between maxillary and mandibular data showed correlations between the torque of the teeth 16/46 and 65/85 (P<0.05).
RME anchored on primary molars is an effective treatment option to correct tranverse maxillary deficiencies. All the measurements increased significantly confirming the indirect effect of RME on the mandibular arch.
本研究旨在评估快速上颌扩张（RME）对上颌和下颌弓在混合牙列中的影响。
共招募了 44 名患有横向上颌发育不全的连续患者。实验组：21 名患者（10 名男性，11 名女性；7.4±1.2 岁）接受 Haas 型 RME 治疗，在上颌第二乳磨牙上带环。对照组：17 名患者（10 名男性，7 名女性；7.3±1.1 岁）未接受任何正畸治疗。治疗前和去除矫治器后（11 个月）获得的牙模通过三维扫描仪（3Shape D250 激光，DK）进行处理。使用 VAM 软件（Canfield Scientific Inc.，Fairfield-NJ，USA）追踪数字标志点。在去除矫治器前后测量牙弓长度、牙间宽度和转矩差异。应用配对数据 t 检验（P<0.05）评估治疗前后的测量值。采用线性回归模型评估治疗效果之间的相关性。
RME 对上颌和下颌弓均有效。下颌磨牙间宽度（+2.02mm）以及第一磨牙间宽度（+1.39mm）、尖牙间宽度（+0.95mm）和转矩变化显著增加。未接受治疗的对照组 T0 和 T1 之间无显著统计学差异。上颌和下颌数据的线性回归显示，牙齿 16/46 和 65/85 的转矩之间存在相关性（P<0.05）。
在上颌乳磨牙上带环的 RME 是一种有效的治疗横向上颌发育不全的方法。所有测量值均显著增加，证实了 RME 对上颌弓的间接影响。
