Twelve percent of the population suffers from chronic pain in the region of the ear, jaw, and muscles of the face, known collectively as Temporomandibular Disorders, or TMD. Pain is the most common characteristic of these disorders, although they are also associated with impairment of jaw function, resulting in the inability to eat or communicate normally.
Despite its widespread prevalence and disabling impact on sufferers, until recently there were no reliable and systematic diagnostic criteria for these disorders. The lack of criteria "resulted in tremendous confusion in the field," says UW professor of oral medicine Samuel F. Dworkin, as workers around the world used imprecise examination procedures and terminology to attempt to diagnose the various types of TMD.
Based on epidemiological data gathered in collaboration with the Group Health Cooperative of Puget Sound from 1986 to 1991, a team of UW investigators led by Dworkin has developed the first available set of diagnostic criteria for TMD disorders. The criteria were published in 1992. "No other comprehensive system exists," says Dworkin, for simultaneously diagnosing the pathological condition while assessing behavioral impacts of TMD as well.
Research results were disseminated to the clinical research community in the form of computerized diagnostic algorithms and clinical protocols. They have even been translated into French and Swedish and disseminated abroad. The research was carried out by Dworkin in collaboration with Linda LeResche and Edmond Truelove of the UW Department of Oral Medicine and Michael VonKorff of Group Health's Center for Health Studies.