Date: May 2021.
Source: Angle Orthodontist. https://doi.org/10.2319/122120-1023.1.
Objective: To evaluate the effects of rapid maxillary expansion (RME) and mandibular midline distraction osteogenesis (MMDO) on facial soft tissues using three-dimensional (3D) images.
Materials and Methods: A total of 20 patients (average age 15.86 ± 2.17 years) were treated with RME and MMDO using tooth-borne distractors. Three-dimensional photographs of each patient were taken with a stereophotogrammetry system at baseline (T0), at the end of the distraction period (T1), and at the end of the consolidation period (T2). All data were analyzed using a dependent-samples t-test at a significance level of 5%.
Results: Total and lower face height increased after MMDO (P < .05). Nasal and mouth width increased after RME as compared with baseline (P < .05). The labiomental angle increased at T1 and decreased at T2 (P < .05). After MMDO, the convexity angle increased while the mandibular angle decreased (P < .05). Upper and lower lip angles increased after RME (P < .05). The distance from the lower lip to the E plane increased after MMDO and decreased after RME (P < .05).
Conclusions: The MMDO and RME procedures provide an efficient non-extraction treatment alternative for transverse maxillomandibular deficiency. MMDO may improve the facial soft tissue profile in the transverse and vertical axis of the mandibular region.

Article: Three-dimensional soft tissue evaluation after rapid maxillary expansion and mandibular midline distraction osteogenesis
Authors: Seyit Ahmet Öztürk, Sıddık Malkoç, Ümit Yolcu, Zehra İleri, Özge Çelik Güler.