The aim of this study was to analyze the incident and accident reports in past submitted from Division of Oral and Maxillofacial Surgery, Iwate Medical University, and to collect the information for improvement of safety management. The subject was the incident and accident reports submitted in the past five years from April 1, 2015 to March 31, 2020. The analysis items are the year, the place, the month, the day of the week, the time, the years of experience of the parties, contents, and level classification. The total number of reports was 56 cases, showing an increasing trend with year. Most of the occurrence place was outpatient. Regarding the months, it seemed to occur before and after the summer vacation, and it seemed to occur before and after the weekend on the day of occurrence. Occurrence time was often in the afternoon. No relationship was found in the years of experience of the parties. The main contents were prescription / drug-related errors, unnecessary / improper inspection or treatment, residual foreign matter in the body, bar fracture, remaining dentin after tooth extraction, and insufficient confirmation of patient information. Level 1 was the most reported by level classification. We would like to improve the medical safety management by referring to the results of this analysis.

Verruciform xanthoma is considered to be a rare tumor-like lesion. We report a case of large oral verruciform xanthoma in an 87-year-old man. Intra-oral examination revealed an irregularfolded and whitish surfaced mass of buccal mucosa measuring 50 × 20 mm in size. Clinically, malignant tumor was suspected because of partial erosion with hemorrhage was recognized on the mass. A biopsy specimen showed the lesion to be suspected as verruciform xanthoma. Under general anesthesia, the lesion was surgically resected. Oral verruciform xanthomas were usually less than 30 mm in size, and this case was the largest one described so far. Post-operative course was uneventful with no sign of recurrence for 1.5 year after surgical treatment.