An animal study - underutilized vista of research in dentistry with special reference to biocompatibility of root canal sealer

Abstract

Background: Endodontic sealers are designed to be used only within the root canal but are frequently extruded through the apical constriction and often placed in intimate contact with periapical tissues for extended periods of time. Hence, assessment of biocompatibility of endodontic sealers is critical to the clinical success of endodontic therapy. Materials and Methods: Eighteen Wistar rats were divided into three groups of 6 each for observation after completion of 14, 30 and 90 days following implantation, respectively. Polyethylene tubes filled with new sealer, and tube without sealer [control] were implanted subcutaneously. The sample subcutaneous tissues from sacrificed rats were analyzed histologically for inflammatory response and were graded with FDI criteria as minimal, moderate and severe. Results were analyzed statistically with Student's t-test and ANOVA tests. Results : Inflammatory reaction to the polyethylene tube was minimal at 14 and 90 days period and to the new sealer it was severe at 14 days and moderate at 30 and 90 days period. Conclusions: 1. Cytotoxicity of the individual ingredient of the new sealer should be investigated to find out its chemical reaction occurring at tissue interface resulting in persistence of inflammation. 2. This subcutaneous implantation method is a practical method for qualitative evaluation of endodontic material and can yield exact detailed information about tissue reaction of material on a cellular level. 3. Hence, animal study is positive, efficient and valuable method to carry out research successfully in dentistry.