Faculty Bibliography

To assess the effect of experimentally induced insulin-dependent diabetes mellitus (IDDM) on total body lipid composition, homogenates of neonatal (0-day) and 6-day Sprague-Dawley rat pups treated on day 0 with 65 mg/kg body weight of streptozotocin (STZ) or citrate buffer alone were compared using thin-layer and gas-liquid chromatographic techniques. STZ-treated littermates in a parallel study were markedly hyperglycemic, hypoinsulinemic and attained only 50% of the gain in weight of citrate-treated controls. Although both groups were similar in protein to body weight ratios, STZ-treated pups exhibited 60% of the total lipid content of citrate-treated littermates when compared by weight. The decrease in total lipid content in the STZ-treated group resulted specifically from decreased neutral and not phospholipid content, although a small increase in phosphatidic acid and sphigomyelin was observed in this group. The changes in relative whole body lipids with short-term, high-dose STZ parallel those reported in human IDDM.

Use of a retarder with a light-bodied addition silicone according to the manufacturer's recommendations increased the working time but resulted in poorly fitting crowns fabricated from these impressions. The compression set of the retarded mixes at the recommended time of removal was 3.2% compared with 0.08% for the nonretarded control. Increasing the time for removal by one minute resulted in a satisfactory compression set of 0.19%. It is recommended that if a retarder is used with an addition silicone, the correct time of removal should be determined by the compression set.