Yun-Fang Chen1,2,3,4, Yu-Fang Liao5,6,7,8, Yin-An Chen2,3,9, Yu-Ray Chen2,3,4,9. 1. Department of Craniofacial Orthodontics, Chang Gung Memorial Hospital, Taipei, Taiwan. 2. Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan. 3. Craniofacial Research Center, Chang Gung Memorial Hospital, Linkou, Taiwan. 4. College of Medicine, Chang Gung University, Taoyuan, Taiwan. 5. Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan. yufang@cgmh.org.tw. 6. Craniofacial Research Center, Chang Gung Memorial Hospital, Linkou, Taiwan. yufang@cgmh.org.tw. 7. College of Medicine, Chang Gung University, Taoyuan, Taiwan. yufang@cgmh.org.tw. 8. Department of Craniofacial Orthodontics, Chang Gung Memorial Hospital, No. 123, Dinghu Road, Guishan District, Taoyuan, 333, Taiwan. yufang@cgmh.org.tw. 9. Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, Linkou, Taiwan.
Abstract
OBJECTIVES: Facial asymmetry is one of the main concerns in patients with a dentofacial deformity. The aims of the study were to (1) evaluate the changes in facial asymmetry after bimaxillary surgery for asymmetric skeletal class II deformity and (2) compare preoperative and postoperative facial asymmetry of class II patients with normal controls. MATERIALS AND METHODS: The facial asymmetry was assessed for 30 adults (21 women and 9 men, mean age: 29.3 years) who consecutively underwent bimaxillary surgery for asymmetric skeletal class II deformity using cone-beam computed tomography before and at least 6 months after surgery. Thirty soft tissue and two dental landmarks were identified on each three-dimensional facial image, and the asymmetry index of each landmark was calculated. Results were compared with those of 30 normal control subjects (21 women and 9 men, mean age: 26.2 years) with skeletal class I structure. RESULTS: Six months after surgery, the asymmetric index of the lower face and total face decreased significantly (17.8 ± 29.4 and 16.6 ± 29.5 mm, respectively, both p < 0.01), whereas the asymmetric index of the middle face increased significantly (1.2 ± 2.2 mm, p < 0.01). Postoperatively, 53% of the class II patients had residual chin asymmetry. The postoperative total face asymmetric index was positively correlated with the preoperative asymmetric index (r = 0.37, p < 0.05). CONCLUSIONS: Bimaxillary surgery for patients with asymmetric class II deformity resulted in a significant improvement in lower face asymmetry. However, approximately 50% of the patients still had residual chin asymmetry. The total face postoperative asymmetry was moderately related to the initial severity of asymmetry. CLINICAL RELEVANCE: These findings could help clinicians better understand orthognathic outcomes on different facial regions for patients with asymmetric class II deformity.
OBJECTIVES: Facial asymmetry is one of the main concerns in patients with a dentofacial deformity. The aims of the study were to (1) evaluate the changes in facial asymmetry after bimaxillary surgery for asymmetric skeletal class II deformity and (2) compare preoperative and postoperative facial asymmetry of class II patients with normal controls. MATERIALS AND METHODS: The facial asymmetry was assessed for 30 adults (21 women and 9 men, mean age: 29.3 years) who consecutively underwent bimaxillary surgery for asymmetric skeletal class II deformity using cone-beam computed tomography before and at least 6 months after surgery. Thirty soft tissue and two dental landmarks were identified on each three-dimensional facial image, and the asymmetry index of each landmark was calculated. Results were compared with those of 30 normal control subjects (21 women and 9 men, mean age: 26.2 years) with skeletal class I structure. RESULTS: Six months after surgery, the asymmetric index of the lower face and total face decreased significantly (17.8 ± 29.4 and 16.6 ± 29.5 mm, respectively, both p < 0.01), whereas the asymmetric index of the middle face increased significantly (1.2 ± 2.2 mm, p < 0.01). Postoperatively, 53% of the class II patients had residual chin asymmetry. The postoperative total face asymmetric index was positively correlated with the preoperative asymmetric index (r = 0.37, p < 0.05). CONCLUSIONS: Bimaxillary surgery for patients with asymmetric class II deformity resulted in a significant improvement in lower face asymmetry. However, approximately 50% of the patients still had residual chin asymmetry. The total face postoperative asymmetry was moderately related to the initial severity of asymmetry. CLINICAL RELEVANCE: These findings could help clinicians better understand orthognathic outcomes on different facial regions for patients with asymmetric class II deformity.
Entities:
Keywords:
Asymmetry index; Class II malocclusion; Facial asymmetry; Orthognathic surgery
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