The effect of diabetes mellitus on histopathological changes in the tissues under denture base bearing masticatory pressure

The effect of streptozotocin-induced diabetes mellitus on histopathological changes in tissues bearing masticatory pressure exerted through an experim ental denture base has been studied in animal specimens. Experimental dentu res, which prescribed the masticatory pressure by the amount of subsidence of the denture base (100, 50 or 13 mu m), were constructed for the hard pal ate of the molar regions of rats. It was revealed that streptozotocin-induc ed diabetes mellitus (1) weakened the intercellular junctions in the epithe lium and gradually enhanced this state with time, (2) lessened the atrophic and proliferative reactions in the epithelial ridge and prolonged their ap pearance period, (3) enhanced the compression of lamina propria mucosae and prolonged the appearance period of this reaction, (4) enhanced the inflamm atory change and extended its appearance period, (5) lowered the threshold for the inflammatory reaction induces by the masticatory pressure, (6) incr eased the number of osteoclasts and prolonged the period of their presence, (7) lowered the threshold for osteoclastic bone resorption induced by the masticatory pressure, (8) inhibited the appearance of osteoblasts following the disappearance of osteoclasts and (9) accelerated the decline rate of m asticatory pressure exerted to the denture supporting tissues. Therefore, i t can be concluded that the streptozotocin-induced diabetes mellitus in the animals tested deteriorated the tolerance of the denture supporting tissue s to masticatory pressure.