A histometric/scanning electron microscope study of normal and loaded oral epithelium of the vervet monkey.

To investigate the functional significance of the epithelial cell surface features found in oral mucosa, a histometric analysis of the pits, microvilli and microplications was carried out in normal and mechanically loaded attached gingiva and alveolar mucosa of the vervet monkey throughout the full thickness of the epithelium. An electronic image analysing system and point counting methods were used to obtain the necessary data from micrographs of tissue specimens viewed in the scanning electron microscope. The results indicate that the cell area increases and the density of microvilli and microplications decreases from the deepest to the superficial cell layers. There was no statistically significant difference between the diameter of the pits and microvilli in the attached gingiva. Similarly there was no statistically significant difference between the widths of the grooves on the oral cell surface and the microplications on the under-surfaces of the alveolar mucosa cells. This indicates that the cell surfaces are complementary within each tissue type. Furthermore mechanical loading caused a significant decrease in the density of microvilli and microplications in the two tissues, confirming that these structures serve as reserve areas for cell stretching.