Is it Possible to Obtain a Predictive Model for Occlusal Stability in Surgery First Orthognathic Surgery? An Exploratory Hypothesis-Generating Study

Orthognathic surgery is a surgical procedure for repositioning the maxillomandibular bone bases in patients with dento-skeletal discrepancies. “Surgery First” philosophy is a challenging approach for breaking paradigms through relativization regarding occlusal determinism for stability. The aim of this study was to analyze the trend of predictive occlusal stability in 36 Amazonian patients and candidates for orthognathic “Surgery First”. The variables gender, age, etiology, existence of orthodontic intervention, number of teeth, surgical movements, number of total contacts, their distribution by segment and intensity were considered. For this, medical records and virtual models made available by the Arch Vertical Collision Map tool of the Dolphin Imaging software were analyzed after the virtual planning was completed. Data were tabulated and processed in Bioestat 5.0 software (Mamirauá Institute). The sample consisted of individuals with a mean age of 36 years and a mean number of teeth of 28 elements; 81% did not undergo any orthodontic intervention prior to surgery. It was not possible to predict the number and intensity of occlusal contacts according to the type of surgical movement and etiology. Orthodontic intervention in the mandible, even if minimal, has the potential to influence postoperative stability and provide less intense contacts; the number of teeth is not an isolated predictor of stability.