The author have analysed the patients of Dept. of prosthodontics in the Infirmary, College of Dentistry, S.N.U., by age and sex, month and year. The results are as follows; 1. 1958 to 1962, 1730 patients were visited. And male patients are superior in number by the ratio 51.38% (889) : 48.61% (841) 2. The age group of 21-30 are most superior in number and it occupied perage, the patients are decreased by the number. 3. The number of patients are rare in March and in 1962 for 5 years. 4. characteristics of educational clinic are evident, for example; summer and winter vacation, term and curriculum etc. 5. It is suggested that dental treatments are related to political and economical current, and social problems.