The Study Of Condylar Position And Asymmetry In Unilateral Scissors-bite Patients With Cone-beam Computed Tomography

ObjectiveThe purpose of this study to investigate differences of condylarsymmetry and condyle-fossa relationship of patients with unilateral scissorsbite. That can be used as theory evidence for diagnostic purposes andplanning orthodontic treatment.MethodsForty-nine subjects with unilateral scissors-bite were selected asexperimental group from the affilited stomatology hospital,ChongqingMedical University.Twenty-eight adolescent patients（10males,18females,ranging in age from11years to15years，average age of13.57±1.00years）and twenty-one adults（7males,14females, ranging in age from18years to25years，average age of20.95±1.50years）.Fifty adults with normalocclusion were selected as control group at the same time.Twenty-eightadolescent subjects（8males,20females, ranging in age from11years to15years，average age of13.68±1.09years）and twenty-two adults（6males,16 females, ranging in age from18years to25years，average age of21.32±2.61years）.The CBCT were taken before orthodontic treatment. Themeasurement of joint space was taken by Invivo5software;Themeasurement of anteroposterior diameter, medio-lateral diameter, volume,surface area and height of condylar was taken by Mimics10.0software,calculate asymmetry index.Results1.In the adolescents，there was statistically significant difference injoint space between experimental group and control group subjects(P＜0.05)；Condylar height asymmetry index in experimental group higher thancontrol group(P＜0.05),but there was no statistically significant differencein condylar morphology between scissors-bite side and nonscissors-biteside in experimental group(P＞0.05).2.In the adults,there was statistically significant difference in condylarmorphology between scissors-bite side and nonscissors-bite side inexperimental group. Condylar height，volume and surface area on thenonscissors-bite side smaller than those on the scissors-bite side(P＜0.05).Condylar height,anteroposterior diameter and medio-lateral diameterasymmetry index of experimental group higher than control group(P＜0.05).3. Condylar height and medio-lateral diameter asymmetry index ofadult experimental group higher than adolescent group(P＜0.05). Conclusion1. Adolescent unilateral posterior scissors-bite patients condylarposition changed，condylar position in scissors-bite side more anterior;Subjects have condylar morphology symmetrical.2. Adult unilateral posterior scissors-bite patients condylar morphologyasymmetry and have normal condylar position.3. The asymmetry of condylar morphology increase with age...