Biocompatibility of two calcium hydroxide-based endodontic sealers: A quantitative study in the subcutaneous connective tissue of the rat

Abstract

In this study, the biocompatibility of two calcium hydroxide-based endodontic sealers was investigated. Silicone tubes containing freshly mixed Sealapex or CRCS were implanted in the dorsal subcutaneous connective tissue of the rat. Equal size solid silicone rods were also implanted and used as controls. The tissue reaction to test and control materials was histometrically and quantitatively analyzed under light microscopy. After 7, 30, and 90 days of implantation, different grades of tissue reaction to the tested materials were recorded at the end of the tubes. A granulomatous tissue containing foreign body giant cells and macrophages with engulfed material in their cytoplasm as well as many fibroblasts and vessels was initially observed in contact with Sealapex. This reaction increased progressively at the 30- and 90-day observation period. An acute inflammation was detected in tissues in contact with CRCS. However, the severity of this reaction decreased with time and it seemed to be resolved at the 90-day observation period. Taking into account the limitations of the experimental model used in this study, we consider that more extensive experiences will be necessary prior to extrapolating these findings to the actual clinical situation.