Objective: to analyze the prevalence of TMD subtypes according to RDC/TMD classification in outpatients at the Head Institute of Federal University of São Paulo.
Subjects and methods: 186 patients, 158 females, 28 males, 15 to 90 years of age, were examined over the period from June 2001, to April 2002 at the Head Institute of Federal University of Sao Paulo. A detailed clinical history was obtained, and the patients were submitted to clinical exam, including cervical functional and extraoral exams, in addition to RDC protocol. Intraoral exam consisted of observation of soft tissue alteration, periodontal disease, and teeth lesions.
Results: Myofascial pain was observed in 136 (73%) patients, 106 without mouth opening limitations, and 30 with limitation. 14 (8%) patients presented temporomandibular joint disorders: 9 with disc displacement with reduction, 4 without reduction nor limitation of mouth opening, and 1 without reduction but with limitation of mouth aperture. 36 (19%) patients presented various associations of the above mentioned conditions. Of these combinations, the association of myofascial pain, without limitation of mouth opening along with disc displacement with reduction was the most frequent (20/36).
Conclusion: There was a marked prevalence of females to males, 5.6:1, among those with complaints related to TMD. Undoubtedly, there was also a prevalence of TMD in consequence of myogenic alteration. A better understanding of mastigatory muscle function might help towards improving the treatment approaches to those patients.