A Case Report of 7 Cases of Oral Cancer Caused for Prosthesis

We have experienced the 7 cases of oral cancer which were caused for prosthesis.When we observed them, we have gained the following results.1) The average of the age was 59.1 S. D.±13.7 years old.2) In respect of sex, the male were 5 cases and the female were 2 cases.The male caused more than the female.3) About the location, the cancer of the maxilla was one, the tongue were 2 cases, and the mandible were 4 cases.4) About the stage classification of TNM system, the Stage II were 4 cases, the Stage III was one, and the Stage IV were 2 cases.5) About the chief complaint, there were many pain due to ill-fitting prosthesis.6) About the visual form classification of WASHIZU's classification, the ulcer type were 4 cases, the erosion type was one, the granulation type was one, and the other type was one.7) Diagnosing by the histologic features, 7 cases were squamous cell carcinoma. The atypia of tumor cells was low, but the developmental degree was mature tumor.8) About the prosthesis, the complete dentures were 3 cases, the partial denture was one, and the crown and bridges were 3 cases.They were made of denture resins and Au-Pd-Ag alloy. All dentures were ill-fitting, and tremble.9) About the caused part of the prosthesis, the denture border were 3 cases, the basal surface was one, the pontic was one, and the cusps were 2 cases. And about the initial symptoms, the ulcer were 5 cases, the swelling and the erosion was each one.10) The average of the wearing term of prosthesis was 7. 5 S. D.±5.5 years, in the meantime the average of the irritation period was 15.7 S. D.±15.8 months.