Laser doppler flowmetry evaluation as a pulpal vitality test

The more frequently used pulp vitality tests (PVTs) are the thermal (cold and heat) and the electrical stimulus. These tests are, however, subjective, depending on the sensitivity threshold of each individual, and usually fail when immature or recently traumatised teeth are tested. The laser Doppler flowmetry (LDF) have been suggested as a PVT, by evaluating the pulp measured flow (F). The measured quantity F, used to discriminate healthy and non-vital teeth, is sensitive to factors hardly controlled or predictable, such as the LDFs and probe response differences, and the flow variations among individuals. It was suggested recently a new discriminator, F(%), less sensitive to such factors. The PVTs performances for F (%) and F as discriminators, however, were not known. The present study aimed to evaluate the PVTs' performances using the quantities F(%) and F (dif) as discriminators, both derived from F, and to compare, qualitatively and quantitatively, their performances to that obtained by using F. The quantities F(%) and F(dif) are, respectively, the ratio and the difference of the flow from the interrogated tooth and its healthy homologous, being F(dif) a proposed new discriminator. The obtained confidence intervals (95% of significance) of the areas under ROC curves were from 0,964 to 1,000 for F (%); from 0,959 to 1,000 for F (dif) and; from 0,584 to 0,951 for F; showing that F(%) and F (dif) are more reliable discriminators then F. (author)