Proinflammatory Cytokines as Biocompatibility Markers of Root Canal Sealers

Histopathological studies have demonstrated that root canal sealers induce mild to severe inflammatory reactions. Proinflammatory cytokines are one of the main causative agents of inflammation. In situ production of these cytokines can be an indicative of citotoxicity. Objective: In the present work it is studied the in situ expression of proinflammatory cytokines as a biocompatibility marker for dental sealers of different composition. Methods: After inoculating the dorsal dermis of CD-1 mice with AH Plus (epoxy resin based), Tubliseal (Zinc-oxide eugenol based) and Sealapex (calcium hydroxide based), the tissue was prepared for immunocytochemical studies to analyze presence of cells producing IL-1beta, IL-6, IL-12, TNF-alpha and Interferon-gamma. Results: AH Plus induced the strongest reaction (p<0.01), mainly in the acute inflammation, with immunoreactivity to IL-1beta, TNF-alpha and IL-12 in several cells of the dermis, mainly in the inflammatory zone. Few cells of the epidermis were immunoreactive to IL-1beta. Significative difference was found between the amount of immunoreactive cells after inoculation with Tubliseal and Sealapex (p<0.05), only a few cells were immunoreactive to IL-12, IL-1beta and TNF-alpha with Sealapex. IL-12 was the cytokine more highly produced in response to dental sealers (p<0.001). Conclusions: Proinflammatory cytokines are an important key in the pathogenesis of the inflammation caused by root canal sealers. Calcium hydroxide based dental sealer showed better in situ biocompatibility.