A study on the pain-free pulp diagnosis based on the pulpal blood flow measured by a newly designed blood flowmeter for the dental pulp.

本研究旨在提高激光多普勒血流仪（LDF）对人髓血流量（PBF）的检测能力。首先，使用FFT频率分析仪测量志愿者牙髓、指尖、握力、前臂和牙龈的血流速度。结果表明，多普勒效应引起的频移在低频范围内。其次，用两种不同频率范围的LDFs检测志愿者指尖、握力、前臂、牙龈和上正中切牙的血流。正常频率范围的LDF记录到明显的搏动不超过一半的志愿者。而低频LDF则记录了志愿者所有牙髓的脉动信号。研究结果强烈地表明，改进后的激光多普勒流量计比标准流量计具有更高的检测能力。认为PBF检测能力的提高有利于老年受试者的牙髓活力诊断。

The aim of this study was to improve the detection ability of human pulpal blood flow (PBF)using laser Doppler flowmeter (LDF). First, Blood flow velocities of the tooth pulp, fingertip, grip, forearm and gingiva of the volunteers were measured using a FFT frequency analyzer. The results showed that the frequency shift produced by Doppler effect with PBF ranged in low frequencies. Second, Two different frequency range of LDFs were used detect blood flow of fingertip, grip, forearm, gingiva and upper central incis or of the volunteers. The LDF with normal frequency rangerecorded obvious pulsation not more than half of the volunteers. However, the LDF with low frequency range recorded pulsasive signals from all the tooth pulp of the volunteers. The results of our study strongly clearly indicated that the modified laser Doppler flowmeter has higher detection ability than standard flowmeter. The increase of detection ability of PBF is considered to give benefit of pulp vitality diagnosis in aged subject.