Evaluation of the patient with chronic facial pain.

A major difficulty in the investigation of chronic facial pain has been a practical classification permitting the selection of appropriate diagnostic procedures to elucidate the etiology of the pain and to provide appropriate therapy. Categorization of facial pain syndromes into vascular, neuritic, muscular, rheumatic, traction and inflammatory and psychogenic groups provides a useful approach to the problem. Despite the utility of this method and advances in noninvasive diagnostic techniques, many pain syndromes remain refractory to full understanding and/or therapy and will test the physician's patience and perseverance.