Study On The Imaging Characteristics And Its Clinical Significance Of Temporomandibular Joint

imaging analysis of temporomandibular joint (TMJ) is a very important study field in the last half of the century. The imaging examination methods for TMJ include Schuller's position X-ray, Tomography, arthrography, CT, MRI, et al. There have been much reports related on the condyle position, the relationship between disc and condyle, the osteoarthrosis of TMJ by which some theories referred to temporomandibular disorder (TMD) such as the condyle displacement and internal derangement (ID) etc have been raised and been introduced in the clinic work.. But the results of surgery treatment under the guidance of ID theory were reported unsatisfied. The TMJ is one of the most difficult areas in the body to image because both of the form and the size are different widely and at least partially the bony structures of the joint are obscured by the more massive cranial bor es when normal techniques are used for imaging. Techniques for imaging the TMJ are u ually dictated by the diagnostic tasks including documentation of cortical integrity, the spce of TMJ, disk position, etc. But what the index is useful for diagnosing TMD What's its significance The present investigation was carried out on this point. First, to investigate the correlation between X-ray imaging characteristics and anatomical measurement of temporomandibular joint, 18 skulls with stable occlusion were examed by X-ray in lateral, middle and medial third sections and also in coronal section separately. The results showed significant correlation existed in condylar diameters of both medial-lateral dimension and anterior-posterior dimension, but not in the space measurement. So it's practically valuable to dictated the condylar form hut position with tomography X-ray. Second, to study the incomplete-dentition patients for their teeth-lose condition and TMJ function condition. The patients were divided into three groups, the TMD patients group who complain for their symptoms of TMD, the symptomatic subjects of TMD but did not complain for the symptoms of TMD. only be checked out when be treated for repairing of dentition, and the asymptomatic subjects of TMD who asked for dentition repair. The results showed: there were no obvious relationship between the bilateral form, osteo changes of condylars, abnormal occlusion and age with the symptomatic subjects of TMD, but correlated significantly with the number of pairs of occluding-tooth lost. The TMD symptoms related only to the occlusal disorders instead of TMJ imaging showed abnormals. Third, bilateral asymptomatic TMJs of 9 male university students were examined separately with MRI. The results showed: The condyle position, disc-condyle relation and the form of the TMJ disc in asymptomatic subjects varied largly on the oblique saggital section. The disc formation was found varied from closing position to opening. A larger saggital area on opening position than that on the closing position was found. The circle length had no significant difference between those of the two positions. The internal pressure difference between the two positions might be the explanation Conclusion: The significance of the diagnostic values used so long in the clinic such as the bilateral form difference, the condyle position, the condyle-disc relationship and osteo variation of condyle remained obscure clinically. TMD diagnosed according mainly to the sympotoms and signs was found related major to the occlusal disorders. It had...