OPTICAL-DETECTION OF HEMOGLOBIN IN PULPAL BLOOD

An in vitro, flow-through optical system was designed to measure hemog lobin (Hb) concentrations in the pulp space. The system included light -emitting diodes and a silicon photodetector positioned on opposing su rfaces of human teeth, A syringe pump allowed a controlled flow of blo od through the pulp chamber, The Hb concentration was computed as a no nlinear function of transmitted light intensity. Transmitted light int ensities were also used as indicators of oxygenation level, Optical me asurements correlated with Hb values measured by the conventional cyan methemoglobin method (r = 0.993). The mean percentage error was 5.8%, and the standard error of prediction was 0.77 g/dl for Hb concentratio ns ranging from 4 to 20 g/dl, Deoxygenated blood exhibited up to 31% l ower transmitted intensity, Light transmission through teeth may be us eful in the assessment of total Hb and blood oxygenation within the pu lp chamber.