Selective influence of dentin thickness upon cytotoxicity of dentin contacting materials

The effect of three dentin contacting materials on three-dimensional cultures of pulp-derived cells was evaluated in a dentin barrier test device. The test materials (Syntac Classic, Prompt L-Pop, Vitrebond) were applied on dentin disks of different thicknesses ranging from 100 to 500 mu m. After 24 h of exposure with and without perfusion of the test chamber, cell survival was evaluated using the MITT assay and related to a nontoxic control material. Syntac Classic decreased cell activity significantly (p <= 0.0003), independently of the For Prompt L-Pop and Vitrebond a dentin thickness. significant influence of dentin thickness was found on the cell reaction. After exposure of the control material, photometric readings showed no dependency of the cellular reaction on dentin thickness (p > 0.05). It could be demonstrated that dentin acts as a barrier, decreasing the elicited cytotoxicity with increasing thickness. This effect is material related, showing little influence for the nontoxic or the glutaraldehyde containing material.