RELATIONSHIP BETWEEN DENTIN HYDRAULIC CONDUCTANCE AND THE CYTOTOXICITY OF 4 DENTIN BONDING RESINS IN-VITRO

Objectives. Dentine modifies pulpward diffusion of monomers leaching f rom restorative materials. Thus, remaining dentine thickness must be t aken into account during in vitro cytotoxicity tests. This in vitro st udy was designed to determine the influence of dentine permeability on the outcome of a cytotoxicity test. Methods. Dentine slices were made from 36 human third permanent molar teeth. The 36 dentine slices were divided into two groups according to their hydraulic conductance: hig h or low hydraulic conductance. The cytotoxicity of four dentine bondi ng agents of similar cytotoxicity was tested on dentine slices from ea ch group. Four dilutions of the experimental culture medium were teste d: undiluted, 1:2, 1.10 and 1:100. An analysis of variance was used to compare the cytotoxicity of the dentine bonding agents tested on high versus low hydraulic conductance. Results. The cytotoxicity of the hi gh hydraulic conductance (Lp) group was higher than that of low Lp gro up when tested with the undiluted test culture medium (p = 0.001). No difference was obtained with the 1:2, 1:10, 1:100 dilutions. Conclusio ns. Under the conditions of the study, the dentine bonding resins were more cytotoxic when applied onto dentine slices of high hydraulic con ductance. (C) 1998 Elsevier Science Ltd. All rights reserved.