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. T