Aging and microcirculatory dynamics in human gingiva

There have been no published reports characterizing gingival vascular function in humans of different ages. In this study, we compared gingival vascular dynamics in 60 healthy male humans ranging in age from 18-75 years (young, 18-25 years (Y); middle, 35-45 years (M); old, 65-75 years (O), 20 subjects/group). Both videomicroscopy of individual microvessels and laser doppler flowmetry were employed to assess marginal gingival circulation. Systemic cardiopulmonary parameters were monitored as controls. The number of gingival vessels visible in a microscopic field was higher and the number of microvessels exhibiting active flow was lower in M and O compared to Y. There were no differences among age groups in laser doppler flow values (tissue blood flow) or in red blood cell velocity in individual vessels. Although not statistically significant with age there was a trend towards decreasing blood flow velocity in both the laser doppler and videomicroscopic measurements. Blood pressure increased slightly with age. Peripheral oxygen saturation was lower in O compared to Y and M. No differences were seen in heart rate, respiratory rate or end-tidal carbon dioxide concentration. The changes in blood pressure and oxygen saturation were expected. The differences in numbers of visible vessels and the number of vessels with active blood flow may reflect the way the gingival microcirculation adapts with age to changing nutritional needs or to microbial and/or mechanical challenge.