Cytotoxicity, biocompatibility and osteoinductive profile of an MTA-hydrogel-based cement: An in vitro and animal study.

AIM: This study aimed to evaluate the cytotoxicity, biocompatibility and osteoinductive profile of a mineral trioxide aggregate (MTA)-hydrogel-based material (MTA Flow) in comparison with MTA Angelus. METHODOLOGY: Cell viability was evaluated in human periodontal ligament stem cells (hPDLSCs) using the methyl-thiazol-tetrazolium (MTT) colourimetric assay. Polyethylene tubes containing the tested materials and empty polyethylene tubes (control) were implanted in the subcutaneous tissue of Wistar rats. Cellular (lymphocyte infiltration) and extracellular events (ECM; collagen fibres) were analysed in histological sections. Immunohistochemical (collagen I, osteopontin, bone sialoprotein, bone morphogenetic protein4) analyses were also performed. RESULTS: At 24, 48 and 72 h, all tested groups showed cell viability similar to control (p > .05). Regarding biocompatibility, all groups showed similar cellular events represented by a slight inflammatory reaction characterized by hyperaemia and a mild lymphocytic inflammatory infiltrate. The analysis of lymphocytes during the time showed a decrease in these cells in the control group and a significant interaction between MTA Angelus and control (p < .001), with MTA Angelus showing a more extensive inflammatory infiltrate. Regarding fibres, an increase in content was observed in all groups during the experimental time (7, 30 and 60 days), however, no difference was detected among the experimental groups (p = .063). After 60 days, the immunoexpression of bone matrix proteins in the MTA Flow group was similar to or higher than that observed in the MTA Angelus and in the control group. CONCLUSIONS: MTA Flow showed a non-cytotoxic behaviour, biocompatibility and ability to stimulate tissue mineralization.

Topical Aloe Vera (Aloe barbadensis Miller) Extract Does Not Accelerate the Oral Wound Healing in Rats.

The effect of topical application of Aloe Vera (Aloe barbadensis Miller) extract was assessed on the healing of rat oral wounds in an in vivo model using 72 male Wistar rats divided into three groups (n = 24): control, placebo and Aloe Vera (0.5% extract hydroalcoholic). Traumatic ulcers were caused in the dorsum of the tongue using a 3-mm punch tool. The Aloe Vera and placebo group received two daily applications. The animals were sacrificed after 1, 5, 10 and 14 days. Clinical analysis (ulcer area and percentage of repair) and histopathological analysis (degree of re-epithelialization and inflammation) were performed. The comparison of the differences between scores based on group and experimental period, both in quantitative and semi-quantitative analyses, was performed using the Kruskal-Wallis test. The significance level was 5%. On day 1, all groups showed predominantly acute inflammatory infiltrate. On day 5, there was partial epithelialization and chronic inflammatory infiltrate. On the days 10 and 14 total repair of ulcers was observed. There was no significant difference between groups in the repair of mouth ulcers. It is concluded that treatment using Aloe Vera as an herbal formulation did not accelerate oral wound healing in rats.