[Exposit in a biological test].

The biocompatibility of the composite resin materials Exposit and Evicrol was tested by functional studies of the rat incisor and the biological test of the dental pulp of pigs. Exposit shows mainly reversible reactions of the vascular connective tissue both in the vital-microscopical examination of the immediate reaction and in short-term tests (24 hours, 7 days), where positive adaptation reactions (new vessels and revascularization) are to be observed. Evicrol causes distinct and irreversible damages in the pulp of the rat incisor. The results of the vital-microscopical examination are proven by histological checks of the rat incisor. In the morphological picture Exposit shows in pig teeth mainly slight and partly moderate inflammatory pulpal reactions after a period of 30 and 90 days. For Evicrol, however, severe reactions with a massive accumulation of inflammatory cells is to be observed after a period of 30 days. Despite an acceptable and, compared to Evicrol, a better biocompatibility of Exposit there is a demand for an exact pulp protection.