Abstract
The aim of this study is to evaluate the tissue response and the mineralization ability of the endodontic materials BiodentineTM and White Angelus® MTA when compared to calcium hydroxide. 100 Wistar rats will be used. Forty will receive subcutaneous implants, divided into groups of 10 animals for experimental periods of 7, 15, 30 and 60 days. All animals will receive four polyethylene tubes implants containing the three materials to be tested and an empty tube as control group. After each postoperative period, the animals will be euthanized and the polyethylene tubes will be removed with the surrounding tissue and fixed in 10% formalin, then the pieces will be included in paraffin, which will be processed and examined under HE and Von Kossa staining for analysis without polarized light, plus immunohistochemical staining for tenascin and fibronectin. The remaining animals (n=60) will be subjected to pulpotomy. Using the first right and left upper molars, the exposed pulp of 3 groups will receive a protection of the materials to be tested and will be sealed with glass ionomer. A group will be directly sealed with glass ionomer as a control group. For histological analysis, at 7, 15 and 30 days, the parts will be fixed in 10% formalin followed by demineralization in 10% EDTA, embedded in paraffin. The analysis will be performed in HE, Brown and Brenn and immunohistochemical staining for tenascin and fibronectin. The microtomography of the parts will be performed before the demineralization to see if there was the formation of dentine bridge. The histological evaluation criteria for subcutaneous will be 0: no or few cells and no reaction; 1: less than 25 cells and mild reaction; 2: between 25 and 125 cells and moderate reaction, 3: 125 or more cells and severe reaction. Thin fibrous capsule will be considered when < 150¼m thick when > 150¼m. For pulpotomy, the hard tissue formation (continuity, thickness and morphology), pulp inflammation (type, severity and extent), and other histological features of the pulp tissue, including the layer of odontoblastic cells and bacterial penetration will be assessed. The immunostaining evaluation criteria shall be: 0 = Absence of immunostaining; 1 = low standard of immunostaining; 2 = moderate standard of immunostaining; 3 = high standard of immunostaining; 4 = extremely high standard of immunostaining. The results will be analyzed by Kruskal Wallis test (±=0,05). (AU)
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