Objectives: To establish Laser-Doppler-Technology to measure the blood flow in the human pulp and to determine the effect of cigarette smoking on the relative blood flow.

Methods: 60 healthy human volunteers were assigned to three groups of 15 testees according to the cotinine level in their urine: (I-non-smokers) <50µg/l cotinine, (II-passive smokers) £1000µg/l cotinine, and (III-smokers) >1000µg/l cotinine, and to a control group (C). In each individual, relative blood flow (Flux, unitless) was measured in one cariesfree, vital upper first incisor tooth using Laser-Doppler-Technology (DRT4 Perfusion and Temperature Monitor V5.02, Moor Instruments Ltd., Millwey, Axminster, UK; Probe Type DP 1T-V2; System Software V1.2). After collection of the urine a custom made splint holding the probe was attached into the maxilla of the testees. Flux was recorded during two periods of 10.5min, interrupted by a 5.0min smoking period (controls did not smoke; sampling rate 2/sec). Testees smoked one filter cigarette (Marlboro, Philip Morris, Switzerland; 0.9mg nicotine, 12mg condensate). Recordings were mathematically smoothed ignoring the initial and final 30sec. The recordings of the second period (after smoking) were related to those before and expressed as percentages (100%=Flux before smoking). If these percentages were within 100±50% the curve was rated “in 50% interval”, and “out of 50% interval” otherwise. Percent ratings were statistically analyzed (c²-Test, a=0.05)

Results:  The bulk part of the flux recordings was between 5 and 20.

C was found significantly different from all other groups but I, and non-smokers (I) were significantly different from II and III, respectively.

Conclusions: Blood flow in the human pulp as determined using Laser-Doppler-Technology is significantly influenced by cigarette smoke depending on the (non-) smoking history of testees.