Analysis of the skeletal and soft-tissue profiles pre and post orthognathic surgery in Class II and III patients and its relation with the golden proportion

Abstract Introduction The golden proportion, represented by the mathematical ratio 1:1.618, has been investigated in Orthodontics and orthognathic surgery in order to be established as a guide to clinical success related to facial aesthetics. Objective To verify the facial aesthetics of patients with Angle Class II and III deformities pre and post orthodontic-surgical treatment, and to analyze if 13 dental-skeletal patters (ratios) and 5 soft tissue ratios moved closer to or further away from the golden proportion after the orthognathic surgery. Material and method A total of 94 lateral cephalometric radiographs, in which 13 dental-skeletal ratios and 5 soft tissue ratios were measured and compared to the golden number. In addition, 270 examiners performed a subjective analysis of facial esthetics before and after treatment. Result Dental-skeletal ratios 1, 3, 6, 7, 8 and 9 moved closer to the golden number after orthognathic surgery in Class III patients. For the soft tissue profile, only ratio 4 moved closer to the golden number in both Class II and III patients. Regarding the subjective evaluation of facial aesthetics, 91.49% of the facial profiles were considered more harmonic after treatment. Conclusion Considering the methodology, it may be concluded that the golden proportion had little effect on the facial aesthetics evaluation and should not work as a guide for orthodontic-orthognathic planning and treatment.