Rahime Burcu Nur1, Derya Germeç Çakan2, Tülin Arun3. 1. Teaching assistant, Department of Orthodontics, Faculty of Dentistry, Yeditepe University, Istanbul, Turkey. Electronic address: drburcunur@gmail.com. 2. Associate professor, Department of Orthodontics, Faculty of Dentistry, Yeditepe University, Istanbul, Turkey. 3. Professor; private practice, Istanbul, Turkey.
Abstract
INTRODUCTION: The purposes of this study were to (1) evaluate facial asymmetry 3 dimensionally using cone-beam computed tomography (CBCT) and (2) compare the right and left facial hard and soft tissues volumetrically and their interferences on each other. METHODS: The CBCT data of 49 asymmetric (soft tissue menton deviation, ≥4 mm; distance from the facial midline) (mean age, 19.9 ± 5.6 years) and 39 symmetric patients (soft tissue menton deviation, <4 mm) (mean age, 17.8 ± 5.5 years) were exported to the MIMICS software program (version 13.0; Materialise, Leuven, Belgium). Linear, surface distance, angular, volumetric, and surface area measurements were performed 3 dimensionally to assess and compare intragroup and intergroup differences. RESULTS: In the asymmetry group, linear measurements such as ramus height, mandibular effective and corpus length, and absolute mandibular volumetric measurements were significantly decreased (P <0.001), whereas facial mandibular, and soft and hard tissue volumetric measurements made on 3-dimensional images, and linear measurements on 2-dimensional images were increased (P <0.001) on the deviation side. CONCLUSIONS: Facial hard and soft tissue asymmetries can be precisely quantified using CBCT. However, especially in the gonial region where the surface topography shows alterations caused by asymmetry, many anatomic landmarks should be chosen for the assessment of asymmetry. At the gonial level, the compensation of the soft tissues for the hard tissues was found on 2-dimensional images; nevertheless, 3-dimensional right and left volumetric soft tissue evaluations provide evidence for asymmetry.
INTRODUCTION: The purposes of this study were to (1) evaluate facial asymmetry 3 dimensionally using cone-beam computed tomography (CBCT) and (2) compare the right and left facial hard and soft tissues volumetrically and their interferences on each other. METHODS: The CBCT data of 49 asymmetric (soft tissue menton deviation, ≥4 mm; distance from the facial midline) (mean age, 19.9 ± 5.6 years) and 39 symmetric patients (soft tissue menton deviation, <4 mm) (mean age, 17.8 ± 5.5 years) were exported to the MIMICS software program (version 13.0; Materialise, Leuven, Belgium). Linear, surface distance, angular, volumetric, and surface area measurements were performed 3 dimensionally to assess and compare intragroup and intergroup differences. RESULTS: In the asymmetry group, linear measurements such as ramus height, mandibular effective and corpus length, and absolute mandibular volumetric measurements were significantly decreased (P <0.001), whereas facial mandibular, and soft and hard tissue volumetric measurements made on 3-dimensional images, and linear measurements on 2-dimensional images were increased (P <0.001) on the deviation side. CONCLUSIONS: Facial hard and soft tissue asymmetries can be precisely quantified using CBCT. However, especially in the gonial region where the surface topography shows alterations caused by asymmetry, many anatomic landmarks should be chosen for the assessment of asymmetry. At the gonial level, the compensation of the soft tissues for the hard tissues was found on 2-dimensional images; nevertheless, 3-dimensional right and left volumetric soft tissue evaluations provide evidence for asymmetry.
Authors: Hieu Nguyen; Jeong Won Shin; Hai-Van Giap; Ki Beom Kim; Hwa Sung Chae; Young Ho Kim; Hae Won Choi Journal: Korean J Orthod Date: 2021-05-25 Impact factor: 1.372
Authors: Deepal Haresh Ajmera; Richard Tai-Chiu Hsung; Pradeep Singh; Natalie Sui Miu Wong; Andy Wai Kan Yeung; Walter Yu Hang Lam; Balvinder S Khambay; Yiu Yan Leung; Min Gu Journal: Clin Oral Investig Date: 2022-03-23 Impact factor: 3.606