Shinichiro Mori

Imaging features of maxillary osteoblastoma and its malignant transformation

We report two cases of osteoblastoma, one of them an unusual case in a 32-year-old woman in whom a maxillary tumor was confidently diagnosed as an osteoblastoma at the time of primary excision and subsequently transformed into an osteosarcoma 7 years after the onset of clinical symptoms. The other patient developed osteosarcoma arising in the maxilla, which was diagnosed 3 years after the primary excision and is very suggestive of malignant transformation in osteoblastoma. We present the radiological features, including computed tomographic and magnetic resonance imaging studies, of this unusual event of transformed tumor and compare imaging features of benign and dedifferentiated counterparts of this rare tumor complex.

Double Mandibular Canals : Report of a case

We report a forensic case in which bilateral double mental foramina with double mandibular foramina, and double mandibular canals on the left side of the lower jaw were noted in the bleached white skull of an unidentified Japanese male of the estimated age of 50 years.

Causes of inadequate X-ray films in Fukuoka Dental College Hospital

The high incidence of defective X-ray films requires that patients undergo unnecessary and expensive repeat radiation exposure. We investigated the frequency of defective films and its causes to protect patients from unnecessary radiation exposure. Between July and September, 1989 (61.5 days), the number and causes of defective X-ray films processed in our department were evaluated. The films had been requested by the departments of dentistry, medicine, surgery, and anesthesiology. Intraoral radiographs were excluded from the study. Of the total of 5, 261 films, 8.6% were defective. The percentage of defective films was highest when the entire staff of three dariological technicians, one darkroom cleark, and one information cleark were on duty. Eighteen percent of all defective films were without exposure, and 82% with exposure. Radiological technician error was the cause in 63.5% of all defective films, positioning error in 34.6%, and exposure error in 17.8%. Of all defective films, 18.5% were not due to radiological technician error; the patient, mis-handling in the darkroom, and requester error accounted for 8.1%, 6.2%, and 4.2%, respectively. We have implemented various improvements as a result of this survey.The high incidence of defective X-ray films requires that patients undergo unnecessary and expensive repeat radiation exposure. We investigated the frequency of defective films and its causes to protect patients from unnecessary radiation exposure.Between July and September, 1989 (61.5 days), the number and causes of defective X-ray films processed in our department were evaluated. The films had been requested by the departments of dentistry, medicine, surgery, and anesthesiology. Intraoral radiographs were excluded from the study.Of the total of 5, 261 films, 8.6% were defective. The percentage of defective films was highest when the entire staff of three dariological technicians, one darkroom cleark, and one information cleark were on duty. Eighteen percent of all defective films were without exposure, and 82% with exposure.Radiological technician error was the cause in 63.5% of all defective films, positioning error in 34.6%, and exposure error in 17.8%. Of all defective films, 18.5% were not due to radiological technician error; the patient, mis-handling in the darkroom, and requester error accounted for 8.1%, 6.2%, and 4.2%, respectively.We have implemented various improvements as a result of this survey.