ENVIRONMENTAL-EFFECTS ON LASER-DOPPLER PULPAL BLOOD-FLOW MEASUREMENTSIN MAN

The increasing number of experiments using laser Doppler flowmetry in man for pulpal blood-flow recordings leads to questionning of the expe rimental recording conditions. The present study focused on three poin ts: the design of the laser probe holder, the isolation of the tooth, and the influence of the recording site. A rigid polyurethane splint u sed in addition to different isolation devices (cotton roll, metal shi eld, rubber dam) was compared with a silicone splint. The silicone res ulted in significantly higher values (+341%) than the polyurethane spl int. The combination of the polyurethane splint with isolation devices decreased, in all cases, the flux values. The polyurethane/rubber-dam combination was the most efficient in individualizing the pulpal bloo d flow (-69% decrease). Recordings on non-vital teeth confirmed the hy pothesis that there was periodontal contamination of the recorded Bow, as the signal was abolished when using the polyurethane/rubber-dam co mbination. Cervical recording sites gave significantly higher values t han occlusal sites (+42%). It is concluded that, in man, the part play ed by the periodontium may have been underestimated in previous record ings of pulpal blood flow. The use of a rubber dam in combination with a rigid splint to enhance the validity of recordings is proposed. Cop yright (C) 1996 Elsevier Science Ltd.