An in vitro pulp chamber with three-dimensional cell cultures.

To better simulate the in vivo situation, a three-dimensional fibroblast cell culture was introduced into an in vitro pulp chamber model. The system was evaluated by testing a series of dental filling materials. After a 24-h exposure with (0.3 or 5 ml/h) and without perfusion of the pulp chamber, the tissues were subjected to a routine MTT assay. Zinc phosphate cement, conventional glass ionomer cements, a silicone impression material, and zinc oxide-eugenol did not influence cell viability, compared with untreated controls; but, a light-curing glass ionomer cement significantly reduced cell survival. Perfusion of the chambers did not significantly influence the results, but perfusion conditions of 5 ml/h lead to a general decrease of cell vitality. The three-dimensional cell culture system in an in vitro pulp chamber seems to be a substantial improvement, because zinc oxide-eugenol does not evoke a cellular reaction (as is the case in vivo), and the test system is sensitive enough to detect other toxicants.