Influence of retention stress on the tissue response of endodontic sealers

Abstract

The response to physical and social stress is controlled by neurobiological systems and their pro-inflammatory, immunological and metabolic components, which are closely interconnected. Our research group has investigated the relationship between dental materials response and systemic disorders / conditions. In view that endodontic sealers induce inflammatory and reparative processes, this study seeks to correlate chronic stress with the tissue response of different types of endodontic sealers using the ISO 10993-6: 2007 model, for implantation tests in subcutaneous tissue. Twenty-eight Wistar rats will be used, divided into 2 groups (n=14): control rats (C), stressed rats (E). In each rat, 4 polyethylene tubes will be implanted, 1 empty tube for control, and the rest containing one of the types of endodontic sealers selected for the study (Sealapex®, AH Plus® and Endofil®). The evaluation periods will be 7 and 30 days (n=7/time). After euthanasia, the blood will be collected for cortisol measurement by the ELISA method and then the tubes and surrounding tissue will be removed and processed for histological and immunohistochemical analysis. The inflammation will be evaluated in tissue sections stained in H.E and by immunohistochemical staining for tumor necrosis factor alpha (TNF-±), interleukin 6 (IL-6), and interleukin 17 (IL-17); collagen, by staining Picrosírios red; biomineralization, by means of Von Kossa staining and in sections without staining by polarized light, as well as by analyzing the presence of osteocalcin (OCN). The statistics will be performed according to each type of analysis and the significance level of 5% (p <0.05) will be considered.