Histological Evaluation of Reparative Dental Pulp Response to Direct Pulp Capping with Mineral Trioxide Aggregate Versus Simvastatin on the Traumatically Exposed Dental Pulp of Rabbits.

Abstract

Objective: The goal of the current study was to evaluate the reparative effectiveness of the traumatically exposed dental pulp of New Zealand rabbits after its stimulation either with mineral trioxide aggregate (MTA) or simvastatin (SIM) against the conventional methyl cellulose control substance. Subjects and methods: For this study, forty healthy male New Zealand rabbits weighing an average of 1.25 to 1.5 kg at 4 months of age were selected. Four groups of ten rabbits each were randomly selected from among the animals and their traumatically exposed dental pulp was treated as follow: (group 1; normal dental pulp; group 2; methyl cellulose; group 3; MTA; group 4; SIM Pulp exposure was accomplished by creating a class V cavity. in the labial surface of maxillary incisors teeth. After hemostasis, the traumatically exposed dental pulps were capped with either of the tested material, then cavities were filled by resin modified glass ionomer. One week after direct pulp capping, the teeth were extracted, and the animals were sacrificed. fixed, decalcified by formic acid and sodium citrate then microtechnically processed to get tissue sections stained by H&E. Dental pulp of all teeth were comparatively evaluated for the potentiality of the tested material to repair the exposed pulp. The reparative potential of each tested material was then comparatively evaluated in respect to the induced reparative dentin formation and the degree of inflammation. Results: histological examination showed the formation of either partial or complete reparative dentine bridge with MTA group while SIM group exhibited significantly thin reparative dentin bridge formation, inflammation and fibrous tissues formation. Conclusion: Mineral trioxide aggregate (MTA) had considerable reparative effect as a direct pulp capping agent as manifested by its induced dental pulp tissue repair and reparative dentin formation comparable to SIM.