[A fundamental study on assessment of gingival blood flow]

The purpose of this study was to establish the assessment of gingival blood flow by laser Doppler flowmeter (LDF) using three parameters; Velocity, Volume, and Flow. The gingival blood flow (GBF) at the labial attached gingiva of the maxillary incisor was measured by LDF in 10 healthy subjects, 3 men and 7 women. There were inter- and intra-individual variations in the obtained data. CV (coefficient of variance) values in each parameter of GBF while resting were as follows; Velocity: 10.2 approximately 34.5%, Volume:7.7 approximately 45.6%, and Flow: 15.4 approximately 67.6%. The effects of changing position, cold stimulus, and the vasoconstrictor (0.1w/v% epinephrine) on GBF were assessed. All three parameters significantly decreased (p < 0.01) after the cold stimulus. When the position was changed to the sitting position from the lying one, however, there were significantly decrease in Velocity (p < 0.001) and Flow (p < 0.02). On the other hand, the local application of the vasoconstrictor caused significant decrease in Volume (p < 0.01) and Flow (p < 0.01). Consequently, Flow significantly decreased after all the stimuli in the present study, however, the change of Velocity and Volume were variable depending on the type of stimulus. These results suggested that multiple parameters are needed for precise observation and analysis of blood flow.