Clinical study on the prevalence of temporomandibular joint dysfunction in orthodontic patients.

The percentage of potential TMJ dysfunction is high in orthodontic patients. The prevalence of TMJ dysfunction during orthodontic treatment and the correlation between TMJ dysfunction occurrence and orthodontic appliances were studied. One hundred and twenty-five male and 183 female orthodontic patients between 7.2 and 38.3 years of age with a mean age of 13.1 years without TMJ dysfunction at first examination were examined for clinical symptoms. TMJ dysfunction was found in 26 patients (8.6%). The frequency of occurrence of TMJ dysfunction in patients treated with a chin cap appliance was 10.9% (14/129) and 6.7% (7/105) for those treated with a multibracket appliance. Chin cap appliance treatment was begun after the pubertal growth peak in eight patients, during the peak in three patients, and before the peak in three patients. Clinical symptoms continued in four patients who continued to use the appliance under the same conditions, and nine patients who were treated with proper countermeasures became free from clinical symptoms.