A multicenter randomized controlled trial comparing the efficacy of midpalatal suture osteotomy combined with microimplant-assisted rapid palatal expansion with Lefort I and median osteotomy assisted maxillary expansion in the treatment of maxillary deficiency in adults

INTERVENTION: Lefort I and median osteotomy and postoperative maxillary expansion with a tooth‐borne Hyrax‐type expander group:Lefort I and median osteotomy and postoperative maxillary expansion with a tooth‐borne Hyrax‐type expander;Midpalatal suture osteotomy combined with microimplant‐assisted rapid palatal expansion group:Midpalatal suture osteotomy combined with microimplant‐assisted rapid palatal expansion; CONDITION: Maxillary transverse deficiency (MTD) PRIMARY OUTCOME: Contribution of midpalatal suture expansion; SECONDARY OUTCOME: Width of nasal expansion;Width of alveolar arch expansion;Buccal inclination of the crown;Contribution of nasal expansion;Pain intensity;Contribution of alveolar arch expansion;treatment expense;Width of midpalatal suture expansion;Duration of surgery; INCLUSION CRITERIA: 1.Diagnosed with maxillary transverse deficiency, and the required amount of maxillary expansion was 5‐12mm (including 5mm and 12mm) according to Yonsei University width analysis method; 2.Age 18 to 45 years old (including 18 and 45 years old); 3.The midpalatal suture is highly ossified, and the maturity stage of midpalatal suture belongs to stage IV or V. According to the pseudo‐color images of the anterior and posterior coronal planes of the palate after thick layer stacking, the cases of "anterior semi‐ossified and closed posterior ossified and closed" were classified as stage IV, and the cases of "anterior and posterior ossified and closed" were classified as stage V; 4.The follow‐up time was not less than 3 months;