INFLUENCE OF TOOTH CRYOPRESERVATION ON HUMAN DENTIN PERMEABILITY, IN-VITRO

Objectives. In order to use cryopreserved teeth in laboratory studies, cryopreservation must not modify the functional properties of teeth, in particular dentin permeability. The purpose of this study was to ev aluate the effects of tooth cryopreservation on human dentin permeabil ity. Methods. Three hundred and sixty freshly extracted human noncario us third molars were used. The teeth were randomly assigned to two gro ups: 180 teeth were stored in phosphate-buffered saline at 4 degrees C and tested within 4 h of collection; 180 teeth were cryopreserved. Hy draulic conductance was calculated according to the method developed b y Pashley (Outhwaite ef al., 1976). Results. Cryopreserved teeth prese nted a hydraulic conductance of 8.97 x 10(-3) +/- 4.21 x 10(-3) mu L.c m(-2).min(-1).cm.H2O-1 slightly higher than the hydraulic conductance of the freshly extracted teeth of 8.03 x 10(-3) +/- 3.87 x 10(-3) mu L .cm(-2).min(-1).cm.H2O-1. No statistically significant difference was found between the two groups. Significance. Under the conditions of th is study, cryopreservation did not modify dentin permeability.