The influence of surface area on the in vitro cytotoxicity of a range of dental materials.

In the toxicity testing of dental materials the quantity of material used may have a profound influence on the biological response obtained. This was investigated in vitro by assessing the cytotoxicity of equal volumes of nine materials in artificial cavities of three different diameters, chosen to cover the range found in vivo. With seven materials there was a significant increase in toxicity with increasing surface area. The pattern of response of different materials within specific groups was fairly uniform. The degree of toxicity of the test materials relative to controls was also investigated. From the data obtained it is apparent that the maximum cavity diameter appropriate for the material under test must be considered when evaluating the toxicity of dental materials.