In the '70s and '80s, even people in the early stages of TMD typically were treated aggressively on the theory that it was necessary to make their anatomy "normal" by repositioning their teeth or jaws. But 80 percent of repositioned jaw discs slip back again within two years. Many experts now consider that the vast majority of patients with temporomandibular disorders should initially receive noninvasive, reversible therapies; perhaps only 1 to 2 percent of TMD patients, typically people who need total joint replacement because of rheumatoid arthritis or bad implants, can benefit from surgery.
Women in their reproductive years are twice as likely as men to get TMD, probably because the production of oestrogen has the effect of loosening their ligaments.
It is estimated that an improper bite accounts for at most 10 to 20 percent of TMD cases.