Hard and Soft Tissue Changes in Patients with Borderline Class III Malocclusion after Maxillary Advancement or Mandibular Setback Surgery: A Cross-Sectional Study

Abstract

Background: The primary aim of this study was to assess the esthetic profile and hard and soft tissue changes in patients with borderline class III malocclusion after maxillary advancement or mandibular setback surgery. The secondary aim was also to evaluate the patients’ face attractiveness after different surgical treatment. Materials and Methods: This observational cross-sectional study evaluated 50 patients with borderline class III malocclusion with a mean age of 29 ± 4 years treated from 2014 to 2019. They were divided into two groups based on the type of surgical treatment underwent: 13 patients were treated with mandibular setback (4 males, 9 females), and 37 patients with maxillary advancement (16 males, 21 females). Hard and soft tissue parameters were measured pre and postoperative evaluation. Frontal and profile photographs of these patients were judged by 15 orthodontists, 15 oral and maxillofacial surgeons, and 15 laypeople before and after surgery. The most and the least attractive profiles were scored 10 and 0, respectively. T-test was used to analyze normally distributed data while Mann-Whitney test for non-normally distributed data. The Kruskal-Wallis test was used to compare the esthetic judgement between the three groups of observers. Pairwise comparisons were carried out using the Mann-Whitney test. Results: Nasolabial angle, SNA, U1/NA (°), U1/NA (mm), L1/NB (°) and L1/NB (mm) were significantly different between the two groups p<0.04, p<0.001, p<0.001, p<0.005, p<0.07, p<0.08, p<0.01 respectively Orthodontists, oral and maxillofacial surgeons, and laypeople all gave a lower score to mandibular setback and higher score to maxillary advancement in terms of facial profile esthetics (P<0.001). Conclusion: Some cephalometric parameters were significantly different between the two groups. The maxillary advancement seemed to provide better results in facial profile esthetics than mandibular setback for patients with borderline class III malocclusion.