A study on the postoperative stability of occlusal plane in Class III orthognathic surgery patients / 대한치과교정학회지

ABSTRACT

In Patients with severe skeletal discrepancy, surgical orthodontic treatment must be accompanied, and recently two jaw surgery has become a common procedure, resulting in improved esthetics and function. Choosing the position of the occlusal plane in this two jaw surgery is an important factor in postoperative stability. Therefore this must be taken into consideration during the diagnosis and treatment plan. In this study, among patients with skeletal Class III occlusion, 25 patients(8 male, 17 female, average age 23.2+/-3.17) who have undergone two jaw surgery, setting the ideal occlusal plane according to Delaire's architectural and structural cranial analysis. In comparing preoperative(T1). postoperative(T2, average of 15.4 days), and long-term postoperative(T3, average of 32.6 months) lateral cephalometric radiography, the following conclusions have been made. 1. There were no significant changes of the occlusal plane angle after the two jaw surgery, and there were no significant differences between the surgical technique(SSRO and IVRO). 2. The postoperative changes of the occlusal plane had no relationship with the amount of jaw movement, amount of posterior impaction, nor the time relapse after surgery. 3. After two jaw surgery, in the SSRO group there was significant forward movement of the mandible, and in the IVRO group the lower incisors extruded as the mandible moved backward and downward which makes the gonial angle and the mandibular plane angle significantly increased.