Department of Maxillofacial Surgery, Silesian Piasts Medical University, Borowska 213, Wrocław 50-556, Poland.
Biomed Res Int. 2020 Jan 23;2020:5814103. doi: 10.1155/2020/5814103. eCollection 2020.
Maxillary constriction is a common skeletal craniofacial abnormality, and transverse maxillary deficiency affects 30% of patients receiving orthodontic and surgical treatment. The aim of the study was to analyse craniofacial skeletal changes in adults with maxillary constriction after transpalatal distraction. The study group consisted of 36 patients (16 women) aged 17 to 42 years ( = 27.1; SD = 7.8) with a known complete skeletal crossbite and who underwent transpalatal distraction procedure. The measurements were obtained on diagnostic models, and cephalometric PA radiograms were obtained at time points, i.e., before treatment (T1) and after the completion of active distraction (T2). The analysis of diagnostic models involving the arch width measurement at different levels demonstrated a significant increase in L1, L2, L3, L4, L5, and L6 dimensions after transpalatal distraction. The largest width increase (9.5 mm) was observed for the L3 dimension (the intercanine distance). The analysis of frontal cephalograms displayed a significant increase in W1, W2, and W3 dimensions after transpalatal distraction. The largest width increase (4.9 mm) was observed for the W1 dimension at the level of the alveolar process of the maxilla. Transpalatal distraction is an effective treatment for transverse maxillary deficiency after the end of bone growth. The expansion observed on diagnostic models is close to a parallel segment shift mechanism, with a mild tendency towards a larger opening anteriorly. The maxillary segment rotation pattern analysed based on the frontal cephalograms is close to a hand fan unfolding with the rotation point at the frontonasal suture.
上颌骨狭窄是一种常见的颅面骨骼畸形，横向上颌骨发育不全影响 30%接受正畸和手术治疗的患者。本研究旨在分析经腭骨扩张术后上颌骨狭窄成人的颅面骨骼变化。研究组由 36 名患者（16 名女性）组成，年龄 17 至 42 岁（均数 = 27.1；标准差 = 7.8），患有已知的完全性骨骼反颌，并接受了经腭骨扩张术。测量值来自诊断模型，头颅侧位片在治疗前（T1）和主动扩张完成后（T2）的时间点获得。涉及不同水平弓宽测量的诊断模型分析显示，经腭骨扩张后 L1、L2、L3、L4、L5 和 L6 尺寸显著增加。L3 尺寸（尖牙间宽度）的增大量最大（9.5 毫米）。经腭骨扩张后，额骨侧位片的 W1、W2 和 W3 尺寸显著增加。上颌牙槽突水平 W1 尺寸的增大量最大（4.9 毫米）。经腭骨扩张是骨生长结束后治疗横向上颌骨发育不全的有效方法。诊断模型上观察到的扩张接近平行段移位机制，前向有轻微的开大趋势。基于额骨侧位片分析的上颌段旋转模式接近手风琴展开，旋转点在前鼻嵴缝。
