Does the Timing of Orthognathic Surgery Affect the Level of External Root Resorption?: Surgery-First Approach Versus Conventional Orthognathic Surgery

Objective: This study aimed to compare external root resorption levels, both linearly and areally, on panoramic radiographs in Class III patients whose treatment was completed with the conventional orthognathic surgery and the surgery-first approach. Methods: The study included 20 patients (10 female, 10 male; 23.98 +/- 2.63 y) treated with conventional orthognathic surgery and 18 patients (8 female, 10 male; 27.5 +/- 3.42 y) treated with surgery-first approach was included. Linear and area measurements were made on the digital panoramic radiographs taken before and at the end of the treatment of 38 patients who constituted the sample of the study. The mean changes observed in each group were evaluated using a paired t test. The chronological ages, skeletal features (type of Class III malocclusion), treatment durations, initial values, and mean changes that occurred in each group were compared using independent t test. Results: When the changes in root lengths and root surface areas were evaluated in all teeth in both groups, a significant loss in size was measured (P<0.001). More resorption was observed in teeth 12 and 22 in the conventional surgery group (P<0.05). When the amount of resorption in both groups was compared, there was significantly more resorption in tooth number 12 in the conventional surgery group (P<0.05). Conclusion: The study showed that there was external root resorption in all teeth in both protocols, but the root lengths of the lateral teeth were shortened more in both groups.