We report a rare case of a brain abscess which drained spontaneously in a temporomandibular joint damaged by osteoarthritis. The female patient presented to our hospital with a severe headache and pain in the temporomandibular joint. She showed elevated inflammatory parameters with unknown cause. Magnetic resonance imaging of her whole body revealed a large temporal brain abscess extending into the glenoid fossa of the temporomandibular joint. The brain abscess was incised and drained by neurosurgeons in our hospital and in the same operation we resected the articular disc and the affected part of the right temporomandibular joint. Histological examination confirmed a chronic arthrosis in the resected bone of the temporomandibular joint and an inflammatory abscess in the resected brain tissue. The patient recovered well and the inflammation resolved as seen in postoperative investigations. Magnetic resonance imaging a month later confirmed local consolidation in the brain with no sign of residual inflammation.
