Correlation Between Temporomandibular Joint Osteoarthrosis And Anterior Disc Displacement:A CBCT Evaluation

Objectives: Differences in condylar process morphology and joint space between TMJOA(temporomandibular joint osteoarthrosis)patients and TMJADD(temporomandibular joint anterior disc displacement)patients were observed by cbct(Cone beam Computer Tomography).To explore the relationship between the morphological characteristics of TMJOA patient's condylar process and the morphological characteristics of TMJDD patient's condylar process.To provide a reference for the diagnosis and early prevention and treatment of TMJADD patients.Methods: Thirty TMJADD patients,30 TMJOA patients and 30 TMJOA patients with ADD were included in the study,and 10 persons with normal temporomandibular joint served as controls.Inclusion criteria:(1)The age of 19 to 65 years old,and the mean age of TMJOA patients was controlled at 25-35 years and that of TMJADD patients at 25-35 years.(2)The sex ratio is male: female is about 1: 1.(3)The types of disease are TMJOA,TMJADD and TMJOA with ADD.(4)The patients did not receive any treatment of temporomandibular joint nearly 3 months,and the history is more than 3 months.(5)Patients informed consent and reexamine on time.The exclusion criteria:(1)<18 years old;(2)the history of head and neck radiotherapy;(3)the history of infectious disease;(4)in the period of pregnancy or lactation.The diagnostic criteria for inclusion in the TMJOA is clicking,clicking history and intermittent TMJ twist lock history,the abnormal opening patterns,the limited mouth opening,TMJ area normal palpation,and the CBCT performance is TMJ degenerative changes.The diagnostic criteria for inclusion in the TMJADD is clicking,clicking history and intermittent TMJ twist lock history,the abnormal opening patterns,the limited mouth opening,TMJ area abnormal palpation,and the CBCT performance is the anterior joint space widened and posterior joint space narrowed.Both subjects of the test groups and the control group were selected to scan the TMJ areas with Genora volux9 CBCT.Digital 3D CT X-Ray system software was used to process and reconstruct the CBCT images.Chose axial,saggital and coronal planes as measuring planes.SPSS16.0 software was used to analyze the data statistically.Results: 1.There are 7 significant differences(P <0.05)between the ADD group and the OA group in the data of the distance from condyle process center to sagittal midline,the distance from the innermost point of the condyle process to sagittal midline,the pressure angle of condyle process,the anterior joint space,the superior joint space,the depth of articular fossa and the slope of articular tubercle.2.There are 6 significant differences(P <0.05)between the ADD group and the control group in the data of the anterior joint space,the superior joint space,the posterior joint space,the depth of articular fossa,the slope of articular tubercle and the vertical angle of condyle process.There are 3 significant differences(P <0.05)between the OA group and the control group in the data of the horizontal angle of condyle process,the vertical angle of condyle process and the pressure angle of condyle process.There are 4 significant differences(P <0.05)between the OA with ADD group and the control group in the data of the anterior joint space,the superior joint space,the anterior and posterior diameter of condyle process and the horizontal angle of condyle process.There are 2 significant differences(P <0.05)between the ADD group and the OA with ADD group in the data of the anterior and posterior diameter of condyle process and the distance from the innermost point of the condyle process to sagittal midline.There are 3 significant differences(P <0.05)between the OA group and the OA with ADD group in the data of the anterior joint space,the superior joint space and the anterior and posterior diameter of condyle process.Conclusions:1.The CBCT examination of ADD patients showed: the data of the distance from condyle process center to sagittal midline,the distance from the innermost point of the condyle process to sagittal midline,the pressure angle of condyle process has an increasing trend,and the data of the anterior joint space,the superior joint space,the depth of articular fossa and the slope of articular tubercle has a tendency to decrease.The temporomandibular joint in ADD patients may have undergone degenerative changes.The ADD patients should be treated as early as possible.2.CBCT can accurately reflect the changes of bone structure and joint space in TMJ.