Development of pulpal blood circulation by the simultaneous measurement of blood flow and blood oxygenation

本研究的目的是建立同时测量人牙髓血流和血氧的方法。实验结果如下：1。本研究采用激光多普勒血流仪（LDF）获取髓血流量（PBF）检测区域信息。为此，我们测量了拔除的人类上中切牙根管内的人工血液循环。将被检查牙齿的根尖部分切断，根管从根尖端扩大到2毫米的切牙，再扩大到水泥-牙釉质交界处（CEJ）。将经肝素化和稀释的人外周血泵入牙尖孔，监测血流信号。当根管向CEJ尖部扩展3 ~ 4mm时，几乎没有信号。血流信号随根管扩大的进展明显增加。结果表明，LDF对人牙齿中PBF的检测范围有限。(168 wds) 2。进行了一项研究，以获得有关测量人类牙髓血氧的信息。为此，通过拔牙的透射光的强度充满了不同氧合水平的稀释血液。通过绿光透射的光反映了血液中血红蛋白的数量，而通过红光透射的光则与牙齿中血液的氧合水平有关。此外，通过人体上中切牙的透射光光体积脉搏波（TLP）在绿光和红光作为光源时表现出不同的特征。结果表明，采用不同波长光的TLP可以检测人牙髓血的量和血氧水平。

The purpose of this study was to establish the simultaneous measurement of blood flow and blood oxygenation in the human pulp. Results obtained were as follows :1. A study was performed to obtain information on the detection area of pulpal blood flow (PBF) using Laser Doppler flowmetry (LDF). For this purpose, the artificial blood circulation in the root canals of extracted human upper central incisors were measured. The apical portions of examined teeth were severed and the root canals were enlarged from the apical end to the 2 mm incisal to the level of the cement-enamel junction (CEJ). Heparinized and diluted human peripheral blood was pumped through the apical foramen of the teeth, and the blood flow signal was monitored. Almost no signal was detected when the root canal was enlarged 3 or 4 mm apical to the CEJ. The blood flow signal significantly increased with the progress of root canal enlargement. The results indicated that the detection area of PBF in human teeth using LDF is limited. (168 wds)2. A study was performed to obtain information on the measurement of blood oxygenation in the human pulp. For this purpose, the intensity of transmitted-light through the extracted tooth filled with diluted blood with different oxygenation level. The transmitted-light through green light reflected the amount of blood haemoglobin, while that through red light was related with the oxygenation level of the blood in the tooth. In addion, transmitted-light photoplethysmography (TLP) through the human upper central incisors showed different characteristic between the green light and red light as the light source. (250 wds)Results indicated that TLP using different wavelengths of the light could detect the amount and the blood oxygenation level of the pulpal blood in the human teeth.