Optical detection of hemoglobin in pulpal blood.
An in vitro, flow-through optical system was designed to measure hemoglobin (Hb) concentrations in the pulp space. The system included light-emitting diodes and a silicon photodetector positioned on opposing surfaces of human teeth. A syringe pump allowed a controlled flow of blood through the pulp chamber. The Hb concentration was computed as a nonlinear function of transmitted light intensity. Transmitted light intensities were also used as indicators of oxygenation level. Optical measurements correlated with Hb values measured by the conventional cyanmethemoglobin method (r=0.993). The mean percentage error was 5.8%, and the standard error of prediction was 0.77 g/dl for Hb concentrations ranging from 4 to 20 g/dl. Deoxygenated blood exhibited up to 31% lower transmitted intensity. Light transmission through teeth may be useful in the assessment of total Hb and blood oxygenation within the pulp chamber.
Diaz-Arnold
A M
AM
Department of Family Dentistry, College of Dentistry, University of Iowa, Iowa City 52242, USA.
Arnold
M A
MA
Wilcox
L R
LR
D000818:Animals; D002417:Cattle; D003782:Dental Pulp / Q000098:blood supply*; D006452:Hemoglobinometry / Q000379:methods; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D016018:Least-Squares Analysis; D008027:Light; D055095:Optics and Photonics; D010100:Oxygen / Q000097:blood; D012044:Regression Analysis; D014172:Transillumination
D006454:Hemoglobins; D010100:Oxygen