Reliability of Pulpal Blood-flow Measurements Utilizing Laser Doppler Flowmetry

Abstract

Pulpal blood flow can now be measured non-invasively in the clinic utilizing laser Doppler flowmetry. The purpose of our study was to test (1) whether the position of the measurement probe on the tooth affects blood-flow measurements and (2) whether measurements from identical locations vary over time. Blood flow of one maxillary central incisor was measured in each of 13 volunteers. Measurements were recorded at five different locations on the labial surface of each tooth. Four measurement sessions were performed, and two sets of measurements were recorded at each session. Custom-made splints ensured accurate and reproducible positioning of the measurement probe at each session. Spatial position of the probe had a clear effect on the pulpal blood-flow measurements (p < 0.0001). Measurements made at incisal and gingival locations were less and greater (p < 0.05), respectively, than those made at central locations. Measurements from various mesio-distal locations did not differ (p > 0.05) when made at the same height on the tooth. Pulpal blood-flow measurements recorded at a given site were not consistent across all of the testing sessions (p < 0.0001). Our data suggest that reliable interpretation of longitudinal measurements of pulpal blood flow obtained with laser Doppler flowmetry requires accurate repositioning of the measurement probe. In addition, an adequate control condition should be included to account for bias due to temporal variation.

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References

Edwall, B. ; Gazelius, B. ; Berg, J.-O. ; Edwall, L. ; Hellander, K. ; and Olgart, L. (1987): Blood Flow Changes in the Dental Pulp of the Cat and Rat Measured Simultaneously by Laser Doppler Flowmetry and Local 125I Clearance, Acta Physiol Scand 131:81-91.

Edwards, A.E. (1985): Experimental Design in Psychological Research , 5th ed., New York: Harper & Row, Publishers, Inc.

Gazelius, B. ; Olgart, L. ; and Edwall, B. (1988): Restored Vitality in Luxated Teeth Assessed by Laser Doppler Flowmeter, Endod Dent Traumatol 4:265-268.

Gazelius, B. ; Olgart, L. ; Edwall, B. ; and Edwall, L. (1986): Non-Invasive Recording of Blood Flow in Human Dental Pulp, Endod Dent Traumatol 2:219-221.

Kim, S. (1990): Microcirculation in the Dental Pulp. In: Experimental Endodontics, L.S.W. Spangberg , Ed., Boca Raton: CRC Press, pp. 51-76.

Kleinbaum, D.G. ; Kupper, L.L. ; and Muller, K.E. (1988): Applied Regression Analysis and Other Multivariable Methods, 2nd ed., Boston: PWS-Kent Publishing Co.

Olgart, L. ; Gazelius, B. ; and Lindh-Stromberg, U. (1988): Laser Doppler Flowmetry in Assessing Vitality in Luxated Permanent Teeth, Int Endod J 21:300-306.

Path, M.G. and Meyer, M.W. (1980): Heterogeneity of Blood Flow in the Canine Tooth of the Dog, Arch Oral Biol 25:83-86.

Salerud, E.G. and Nilsson, G.E. (1986): Integrating Probe for Tissue Laser Doppler Flowmeters , Med Biol Eng Comput 24:415-419.

10.

Tenland, T. ; Salerud, E.G. ; Nilsson, G.E. ; and Oberg, P.A. (1983): Spatial and Temporal Variations of Human Skin Blood Flow, Int J Microcirc 2:81-90.