The relationship between the laser Doppler blood-flow signals and the light intensity in the root canals in human extracted teeth.

The relationship between the laser Doppler blood-flow signals and the laser light intensity in the root canal was examined. The root canals of extracted teeth were enlarged from the apical end to the 2 mm incisal to the level of the cement-enamel junction (CEJ). Human peripheral blood was pumped through the apical foramen of the teeth, and the blood flow signal was monitored. Both the light intensities in the root canal and pulpal blood-flow (PBF) signals were small when the root canal was enlarged 3 or 4 mm apical to the CEJ. Both intensities increased with the progress of root canal enlargement to the tooth. There was a significant relationship between the laser Doppler blood-flow signals and the light intensity in the root canals. The results indicated that the laser light intensity in the root canal effected on the PBF in human teeth using Laser Doppler flowmetry (LDF). [ABSTRACT FROM AUTHOR]