The aim of this study was to analyze the prevalence of internal derangement of the temporomandibular joint (TMJ) diagnosed by magnetic resonance imaging (MRI). The following data was evaluated: chief complaint, gender, age, side affected, diagnosis, joint clicking, mouth opening, dental prosthesis and presence of muscle disorders. The sample comprised 59 successive patients (118 TMJs), 46 females and 13 males; ages ranged from 14 to 92 years.

All patients were examined from 2002 to 2006. Anterior disc displacement with reduction was the most common disorder (60 joints); anterior disc displacement without reduction appeared in 17 joints; TNJ effusion (25 joints); open lock (1 joint); TMJ osteoarthritis (8 joints) and no pathology in 7 cases. TMJ click was present in 27 and 32 had no clicking. There were associated muscle disorders in 22 cases. Mouth opening ranged from 10 to 61 mm; 24 patients were using some kind of dental prosthesis. The following conclusions are drawn: anterior disc displacement with reduction is the most common pathological condition in patients submitted to MRI; there is a marked predominance in women; and the presence of muscle pathology associated with intracapsular pathology is more prevalent in women.

Conflict of interest: None declared.