Hypertension Undermines Mineralization-inducing Capacity of and Tissue Response to Mineral Trioxide Aggregate Endodontic Cement

Introduction: This study evaluated the effect of hype-tension on tissue response to and mineralization capacity of white and gray mineral trioxide aggregate (MTA) (Angelus Industry,,Ontological Products, Londrina, Brazil), an endodontic reparative cement. Methods: Polyethylene tubes containing gray MTA, white MTA, or intermediate restorative material (positive control) or an empty tube (negative control) were implanted into the dorsal connective tissue of spontaneous hypertensive and Wistar rats (n = 12 each). Six rats in each group were sacrificed after 7 days, and the remainder after 30 days. Tubes with surrounding tissue were removed, and a histologic analysis was performed using hematoxylin-eosin and von Kossa staining and examination by polarized light microscopy. Results: The inflammatory response to all materials was greater in hypertensive compared with normotensive rats (P < .05). Positive von Kossa staining and birefringent structures in polarized light were observed for both gray and white MTA (P > .05), but these were more pronounced in normotensive rats (P < .05). Necrotic areas with positive von Kossa staining were observed for intermediate restorative material. Conclusions: Hypertension undermines tissue repair and mineralization, which can negatively affect treatment outcome. Nonetheless, mineralization in response to MTA was observed even under hypertensive conditions.