A total of 1, 262 patients of temporomandibular arthrosis who visited the Department of Dental and Oral Surgery at Nagoya University Hospital over a period of 13 years from January 1971 until December 1983 were clinically and statistically observed. The following results were obtained.
1. The number of patients suffering from this disease tends to increase every year, and the percentage of these patiens, out of all new patients, was 1.7% in 1971 and has stayed above 6% since 1978, reaching 7.3% in 1983.
2. By sex, the ratio of male to female patients was 1: 2.66, and the predominance of female patients was significant.
3. By age group, 33.9% of the patients were in the twenties, 18.4% in the teens, 18.3% in the thirties, followed by those in the forties, fifties, over sixties, and under 10. Then distributon was a single-peak curve.
4. The illness manifested on one side in 89.0% and on both sides in 11.0%. In the onesided cases, the left side was more affected than the right side, but there was no significant difference.
5. As the symptom at the initial onset of disease, temporomandibular joint pain was experienced in 39.0% of the cases and temporomandibular joint noise in 30.8%, the sum of which amounts to nearly 70%, and 89.2% of the initial symptoms were single symptoms.
6. As the chief complaint, 70.3% were related to pain, followed by difficulty in opening the mouth, and noise.
7. By cause, 64.9% of the cases were caused by an intrinsic trauma, 22.2% by a spontaneous episode, and 12.0% by an exoteric trauma.
8. The number of visits to our department and the remedies were as follows.
Those visiting five times or less were 56.4%, and the average number of visits per patient was 7.2. The remedies were classified into medical treatment, physical treatment, dental treatment, joint cavity injection and muscular training, or others. Two mehod were applied in 36.2% and three methods in 31.3% of the cases. Above all, the medical treatment was applied to 84.3% of all patiens, and the dental treatment to 53.7%.