Maxillary, Circummaxillary Sutural System,Mandibular Position And Upper-Airway Changes Following Surgically Assisted Rapid Maxillary Expansion—SARME And Surgically Facilitated Orthodontic Therapy—SFOT

Objective:1. The aims of this study were to quantitatively evaluate the changes in Maxillary, circummaxillary sutural system, mandibular position and upper-airway after surgically assisted rapid maxillary expansion-SARME and surgically facilitated orthodontic therapy-SFOT with cone-beam computed tomography (CBCT).2. Evaluate the alveolar bone volume changes after the SARME+SFOT therapy.Methods:From our clinic archives, we selected the CBCT records of 20 patients with the insufficient transverse dimension of the maxilla (11 boys,9 girls, the averageage25 years old with ages from 22 to 32years) who underwent SARME+SFOT treatment. A individualized metal casting bonded rapid maxillary expansion appliance with an hollowed-out occlusal permitting a flat bite block was used in all patients. CBCT records had been taken before SARME+SFOT treatment and after a 3-month retention period. Angular and linear measurements were taken for the maxilla, circummaxillary sutural system, mandibular position and upper-airway. Frontally clipped CBCT images were used for the evaluation. Paired sample t tests were used for statistical comparisons.Result:1. Comparisons of the before-treatment and after-retention measurements showed that the arch widths, the distance between the bilateral circummaxillary sutural system (suture zygomaticomaxillaris and hamuluspterygoideus) and the Ba-PNS distance increased significantly on the both groups(P<0.05).The placement of the appliance created a anterior-superior movement of the position of the maxilla with different direction of the rotation due to the posterior occlusal bite block. The slice area of the nasopharynx in the Ba-PNS level had significant increase. The mandibular had clockwise rotation, but the upper-airway volume bordered by PP-C3iHy had increased significantly.2. The maxilla buccolingual inclinations of the upper teeth had little change after the therapy(P> 0.05). A significant increase of the alveolar bone volume in both the vertical and transverse direction were observed after treatment(P<0.05).Conclusion:1. After SARME+SFOT treatment, the maxilla, circummaxillary sutural system and the volume of the nasopharynx and upper-airway had some significant improvement.2. The alveolar bone volume after the SARME+SFOT treatment increased significantly.