Biological Tissue Response of Endodontic Sealers after Subcutaneous Implantation

This study evaluated the tissue reaction and inflammatory response after implantation of endodontic sealers in the subcutaneous connective tissue of isogenic mice. 120 mice were divided into 4 groups: BioRoot RCS, AH-Plus jet, ZOE and Sham group (negative control), which were evaluated in the experimental periods of 7, 21 and 63 days (n= 10). A macroscopic analysis was performed through digitized photograph to measure the thickness of the reaction tissue. Microscopic analysis were performed to count the number of blood vessels present in the reaction tissue and to evaluate collagen fiber networks. Data were analyzed using the non-parametric Kruskal-Wallis test and Dunn´s post test (α=5%). The reaction tissue showed greater thickness and amount of vessels and blood cells in the initial period of 7 days and was reduced over time, except the group AH Plus Jet which presented similar values of blood cells and vessels in all experimental periods. The BioRoot RCS at 7 days, presented the values of thickness and blood cells in the reaction tissue significantly higher (p˂ 0.001). Regarding collagen fiber formation, there was a greater amount of collagen fibers in the Sham group (7, 21 and 63 days), BioRoot at 63 days and AH Plus Jet at 21 and 63 days. In conclusion, endodontic cements presented greater thickness and amount of blood cells in the initial period, being reduced with time. On the other, collagen fiber formation were more pronounced at final periods.