We investigated the physical properties, antimicrobial activity, and tissue reaction to Apexit Plus in comparison to Sealapex. Flow, radiopacity, setting time, and solubility were evaluated in each material. The antimicrobial activity against Enterococcus faecalis was performed. Polyethylene tubes containing Apexit Plus or Sealapex, and without material (control group) were implanted into the subcutaneous tissue of rats. At 7, 15, 30, and 60 days of implantation, the specimens were paraffin-embedded and the number of inflammatory cells (ICs) and the amount of birefringent collagen (BC) were quantified. The von Kossa reaction followed by immunohistochemistry for detection of alkaline phosphatase (ALP) was also performed. Statistical analysis was performed with ANOVA and Tukey test (p ≤ 0.05). The flow value of Apexit Plus was greater than Sealapex, whereas the radiopacity (3.44 mm Al) was lower than Sealapex (6.82 mm Al). Apexit Plus showed lower solubility and shorter initial and final setting (p < 0.0001), whereas the antimicrobial activity was significantly greater than Sealapex. Although the number of ICs was higher in Apexit Plus (p = 0.0009) at 7 days, no significant difference was detected between Apexit Plus and Sealapex at 15, 30, and 60 days. All groups showed higher values for BC in the capsules over time. ALP-immunolabelled cells were observed, mainly around von Kossa-positive structures, either in the capsules of Apexit Plus or Sealapex. Therefore, our results revealed that Apexit Plus exhibited a greater effectiveness against Enterococcus faecalis and better physical properties than Sealapex, except for the radiopacity. In vivo findings indicate that Apexit Plus is biocompatible and presents potential bioactivity in the subcutaneous tissue.

Although thick MTA Flow induced a less intense inflammatory response, all evaluated materials are biocompatible because they allowed regression of this process after 60 days.

Objectives This study evaluated the biocompatibility and bioactive potential of NeoMTA Plus mixed as a root canal sealer in comparison with MTA Fillapex. Materials and Methods Polyethylene tubes filled with NeoMTA Plus ( n = 20), MTA Fillapex ( n = 20), or nothing (control group, CG; n = 20) were inserted into the connective tissue in the dorsal subcutaneous layer of rats. After 7, 15, 30 and 60 days, the specimens were processed for paraffin embedding. The capsule thickness, collagen content, and number of inflammatory cells (ICs) and interleukin-6 (IL-6) immunolabeled cells were measured. von Kossa-positive structures were evaluated and unstained sections were analyzed under polarized light. Two-way analysis of variance was performed, followed by the post hoc Tukey test ( p ≤ 0.05). Results At 7 days, the capsules around NeoMTA Plus and MTA Fillapex had more ICs and IL-6-immunostained cells than the CG. However, at 60 days, there was no significant difference in the IC number between NeoMTA Plus and the CG ( p = 0.1137) or the MTA Fillapex group ( p = 0.4062), although a greater number of IL-6-immunostained cells was observed in the MTA Fillapex group ( p = 0.0353). From 7 to 60 days, the capsule thickness of the NeoMTA Plus and MTA Fillapex specimens significantly decreased, concomitantly with an increase in the collagen content. The capsules around root canal sealers showed positivity to the von Kossa stain and birefringent structures. Conclusions The NeoMTA Plus root canal sealer is biocompatible and exhibits bioactive potential.