Tissue Response and Immunoexpression of Interleukin 6 Promoted by Tricalcium Silicate–based Repair Materials after Subcutaneous Implantation in Rats

Abstract

IntroductionThe aim of the present study was to evaluate the inflammatory response induced by experimental tricalcium silicate cement with 20% zirconium oxide (TSC) and MTA Plus (MTAP; Avalon Biomed Inc, Bradenton, FL) in rat subcutaneous tissues. MethodsPolyethylene tubes were filled with TSC (n = 20) and MTAP (n = 20) and implanted in the dorsal subcutaneous tissues of 32 rats. Empty tubes were used as the control (control group [CG], n = 20). After 7, 15, 30, and 60 days, the tubes with connective tissue were removed, and the inflammatory cells and immunolabeled cells for interleukin 6 (IL-6) were counted. Data were statistically analyzed using analysis of variance and the Tukey test (P ≤ .05). ResultsAn increased number of inflammatory and immunolabeled cells for IL-6 were observed at 7 days. The number of inflammatory cells was higher for TSC and MTAP than the CG (P < .001) at 7 days; after 30 and 60 days, no significant differences were observed among the TSC, MTAP, and CG (P = .955). The number of immunolabeled cells for IL-6 was similar for TSC, MTAP, and CG at all evaluated periods. A gradual and significant decrease was observed in the number of inflammatory cells and IL-6–immunopositive cells. At 60 days, the capsules adjacent to TSC and MTAP exhibited fibroblasts and bundles of collagen fibers. ConclusionsTSC and MTAP caused a similar subcutaneous reaction in rats, suggesting that they are biocompatible and present similar immune responses.