In order to know the pattern and trend of the temporomandibular dysfunction, out patients at the Tokyo Medical and Dental University Hospital were clinically surveyed and statistically analysed.
Patients suffering from temporomandibular dysfunction were found to be increasing markedly every year. The prevalence was the highest at puberty of around twenty years of age and that in the females was three times that in the males.
Among the symptoms, pain, clicking or popping noise and trismus were the most prevalent. Some patients complained also of shoulder ache, headache, feeling of discomfort in ear or neck, etc. Although about one-half of the patients did not notice the trigger causing the jaw dysfunction, some overloading of the temporomandibular joint such as opening the mouth for a long time or wide and biting hard objects were most often claimed as the triggers. The interval between noticing the symptoms and visiting the hospital varied extensively from several days to several years.