This study was designed to complete the cell culture test for the cytotoxicity assessment of dental material presented by Christen et al. (1989) and Regad et al. (1989). Two liner materials were selected for this experiment which had already been subjected to both in vivo and in vitro tests. After 2, 7 and 14 days of contact with the test materials, the cell responses were evaluated under the light microscope by their growth pattern and morphological aspects. Cell synthesis of fibronectin and type I and III collagen was studied by immunofluorescence. Surface appearance of the cells in contact with the materials as well as their structures were observed by scanning electron microscopy. This study confirmed the viability of the in vitro cytotoxicity assessment methods with cell cultures. The results also demonstrated the potentials of this method in the early screening of dental materials for their biological compatibility.