Baseline (BL) data on signs and symptoms characteristic of temporomandibula
r disorders (TMDs) were analysed in 67 young non-patients participating as
controls in a clinical trial. Data on the incidence of demand for treatment
of TMD were collected during the 4-year follow-up period, and, by means of
a mailed questionnaire, during an additional 2 years. The variables analys
ed included palpation and auscultation of the joints, palpation of the musc
les of mastication, experience of joint sounds, of pain on jaw movements, o
f ear symptoms, awareness of a clenching habit, and frequency of headache.
A present-absent dichotomy was applied throughout. Palpation tenderness of
masticatory muscles was significantly (P=0.02) more often present at BL in
those who subsequently requested treatment than in those who did not. The s
ame was true of the combination of palpatory tenderness and clenching habit
(P=0.007), whereas the clenching habit alone failed to show a significant
difference (P=0.06). However, the predictive values remained too low to be
clinically useful, with a possible exception of the negative predictive val
ue of muscle tenderness. The findings indicate that the variables conventio
nally used to describe the functional status of the masticatory system are
at best of modest value in the estimation of individual risk of TMD in heal
thy young subjects.