Relationship between the TMJ disc and condyle position on MRI and occlusal contacts on lateral excursions in TMD patients

Confusion about the relationship between dental occlusion and the temporomandibular disorders (TMD) has been evident in the literature for many years. Previous studies have supported the concept of a multifactorial aetiology of TMD, the occlusal factor in general being of minor importance. The purpose of the study was to investigate the relationship between condyle and disc positions and occlusal contacts on lateral excursions of the mandible in patients with TMD. A total of 122 temporomandibular joints (TMJs) of 61 patients with TMD were evaluated using magnetic resonance imaging (MRI) and occlusal analyses were made clinically. Non-working-side contacts were found to be statistically significant in TMJ anterior disc displacement. No significant statistical correlation was found between the severity of anterior disc displacement and non-working-side contacts in both canine guidance and group function occlusions. There was no correlation between non-working-side contacts and condyle positions in both occlusion types in the present study. It was concluded that non-working-side contacts had some effect on disc position in TMD, however the presence of these contacts in both canine guidance and group function occlusions did not correlate with anterior disc displacement in TMD statistically. Therefore, non-working-side contacts are not to be regarded as the prime cause of anterior disc displacement.