The effect of short-term tooth intrusion on human pulpal blood flow measured by laser Doppler flowmetry

The purpose was to examine the effect of brief intrusive forces on human pulpal blood flow (PBF). Laser Doppler flowmetric measurements were made from 17 vital upper left central incisors of 17 participants who had clinically healthy tooth crowns and periodontal tissues. Brief intrusive forces (0.5, 1, 5 N; duration 20 s) were applied to the incisal edges of the examined teeth, and apical displacement of the teeth and the PBF were measured simultaneously. Recordings were made with and without an opaque rubber dam applied to the examined teeth. Intrusive force significantly reduced PBF flux both with and without the dam (P < 0.05, Friedman analysis). The results indicate that transient apical displacement can reduce PBF.