Rehabilitation of a Spark Erosion Prosthesis: A Clinical Report

When complex prostheses are fabricated, it is expected that at some point maintenance will be necessary. This clinical report documents a 10-year-old maxillary spark erosion prosthesis that had been repaired many times, was discolored, and exhibited significant signs of wear. The metal superstructure was intact; therefore, only the acrylic resin base and teeth needed to be replaced. To reduce both cost and time without the prosthesis for the patient, the rehabilitation was completed within 24 hours.     

The relationship between histopathological findings in oral squamous cell carcinoma and FDG uptake on PET

Objectives It is known that, in fluorine-18 fluorodeoxyglucose Positron Emission Tomography (FDG PET) for the diagnosis of oral cancer, FDG uptake may vary even among different cases of the same squamous cell carcinoma. However, the details of this phenomenon have not yet been elucidated. In this study, we analyzed the relationship between histopathological findings in oral squamous cell cancer and PET findings on FDG uptake. Methods We examined 45 patients with oral squamous cell carcinoma who had undergone FDG PET before treatment. FDG uptake was assessed by a standardized uptake value (SUV) calculated according to the PET-measured tissue concentration of FDG, the administered dose of radionuclide, and the body weight of the patient. The relationship between the mean SUV and each of the following parameters was examined: histological grade of malignancy, degree of cell differentiation, size and/or local extent of the primary lesion, and cell density of the tumor. Results The mean SUV of FDG uptake did not depend on the histological grade of malignancy or on the degree of cell differentiation, but tended to be greater the larger the primary lesion. SUV also depended on cell density, increasing with the percentage of tumor parenchyma. Conclusions It is concluded that cancer cell density greatly influences the SUV of FDG, in that a tumor with fewer cellular elements in cancer tissue tends to become a false negative.