Statistics suggest that up to three-fourths of Americans suffer some symptom of temporomandibular disorder (TMJ). Symptoms of this disorder include clicking and locking of the jaw, migraines, pain on the sides and back of the neck and head, and ringing in the ears. But too often, experts say, patients fail to have the problem examined in a comprehensive way and undergo costly and sometimes irreversible therapies that may do little or nothing to relieve their symptoms. In this article, a health...