Prevalence of TMJ symptoms and X-ray findings

Some results of the fifteen year longitudinal Groningen study on TMJ dysfunction are reported. The prevalence of subjectively communicated symptoms appears to consistently increase with age. The recording of 21 percent pain at the last check-up was judged high. Objectively determined symptom frequencies (in the literature sometimes indicated signs) seem to level off in the early twenties. Observed X-ray deformities or flattening of the condyle did not increase substantially. The symptoms registered at the successive time points were found to originate to a considerable extent from changing individuals, indicating the unstable character of these symptoms. Furthermore the symptom categories are rarely present simultaneously in one individual. In harmony with these findings it appeared to be nearly impossible to predict any component by the same or any other component at an earlier time point. It is concluded that during growth, and probably due to growth, different signals appear. Some are outgrown, others are followed by serious problems; a third group may develop a new problem at maturity. Future research will be directed to identify these different groups at an early stage.