DENSITIES AND SIZES OF MAIN MASTICATORY MUSCLES IN PATIENTS WITH INTERNAL DERANGEMENTS OF TEMPOROMANDIBULAR-JOINT OBTAINED BY COMPUTED-TOMOGRAPHY

Computed tomography (CT), due to its excellent resolution capacity, is a suitable method to examine the soft and bony structures of the mast icatory system. The aim of this study was to compare densities and siz es of the masseter and medial and lateral pterygoid muscles obtained b y CT between the symptomatic and asymptomatic side in patients with in ternal derangement of the temporomandibular joint (TMJ). The aim was a lso to correlate these variables to sex and age, duration of the sympt oms, diagnosis and dentition. The material consisted of 33 patients (2 6 women, 7 men, mean age 37 years, range 14-74 years) whose TMJs were examined by CT and whose coronal CT scans were available. Diagnosis in the symptomatic TMJ was confirmed in operation. No statistically sign ificant difference was seen in mean densities and sizes of the mastica tory muscles between the symptomatic and asymptomatic side. The durati on symptoms, however, correlated positively density of the lateral pte rygoid muscles in patients with complete dentition. The age of the pat ients in this group correlated negatively to the size of the masseter muscles. It can be concluded that patients with internal derangements of TMJ with a long duration of symptoms have structural changes in the ir masticatory muscles which are detectable by CT.