THE DENTIN DISC - A REVIEW OF ITS APPLICABILITY AS A MODEL FOR THE IN-VITRO TESTING OF DENTIN HYPERSENSITIVITY

The dentine disc has been extensively used as a model for assessing po tential desensitizing agents in vitro by scanning electron microscopy (SEM). Although the disc provides a readily available and reproducible test substrate, this paper addresses the problems associated with thi s model such as the natural variation in the dentine tubules and the r esulting differences in surface morphology. At the ultrastructural lev el the surface of a single etched disc exhibits variations in the size , density, orientation and extent of etching of the cut dentine tubule s. In the present study a precise control procedure was designed which allowed greater correlation between test and control surfaces. Two ad jacent areas of the same disc were used, one as the test surface, the other the control. Two proprietary desensitizers were examined using t his methodology. This study has shown that the dentine disc is a good, reliable model for in vitro screening and testing of potential desens itizing agents, providing such controls are applied.