Evaluation of osteoconductivity and inflammatory response of a resin-based and a resin-free calcium silicate sealer: an in vivo study.

AIM: This study aimed to assess the biocompatibility and osteoconductivity of a resin-based and a resin-free calcium silicate sealer and their ability to promote healing of induced periapical lesions in mature dogs' teeth. MATERIALS AND METHODS: Periapical lesions were induced at 40 mandibular premolars of eight mongrel dogs. Following root canal preparation, the canals were obturated with a single cone and either TotalFill BC (n = 16) or MTA Fillapex (n = 16), while the positive control group (n = 8) remained unfilled. To ensure sealer extrusion during obturation, apical foramina were enlarged intentionally. Histological evaluations were conducted after one and four months, utilizing hematoxylin and eosin staining for inflammatory cell counts, Goldner's trichrome stain for new bone formation, and immunohistochemistry for osteopontin (OPN) expression. ImageJ software was used for quantitative analysis, and statistical comparisons were made using the Kruskal-Wallis and the Mann-Whitney U with Bonferroni's tests (p < 0.05). RESULTS: TotalFill BC Sealer induced a significantly lower inflammatory response than MTA Fillapex (p < 0.05). A significant reduction in inflammation was observed over time. TotalFill BC Sealer exhibited a significantly higher percentage of new bone formation and significantly higher OPN expression than MTA Fillapex and the positive control (p < 0.05). At four months, TotalFill BC Sealer showed enhanced bone formation with minimal residual inflammation, whereas MTA Fillapex demonstrated moderate healing with ongoing remodeling. CONCLUSION: The resin-free TotalFill BC Sealer exhibited superior biocompatibility, promoted faster inflammation resolution, and stimulated more new bone formation compared to the resin-based sealer MTA Fillapex when in direct contact with periapical tissues.