Transforaminal and systemic diffusion of an active agent from a zinc oxide eugenol-based endodontic sealer containing hydrocortisone-in an in vivo model.

Abstract

This study aimed to quantify in vivo the release of hydrocortisone acetate (HCA) contained in a zinc oxide eugenol-based endodontic sealer, in various tissues. Roots of human teeth, shaped with One Shape single file and sealed with Endomethasone N, previously radiolabelled with tritium (3H-HCA), were implanted in the back of 24 mice. Mice were sacrificed at 2, 8, 24, and 48h to evaluate and quantify the amount of radioactivity in subcutaneous tissues surrounding the apex (periapical-like) of the implanted teeth, blood, spleen, kidneys, liver, and urine. Radioactivity was released from the apex of the tooth into the periapical-like tissues with a peak measured at 2h post-implantation (2.25% of the initial radioactivity/g). This quantity decreased significantly over time between 2h and each time points. Radioactivity was still measured up to 48h in the periapical-like tissues (0.42% of the initial radioactivity). The same pattern of kinetic was observed for all organs. The total quantity of radioactivity significantly decreased over time from 4.36% measured 2h post-implantation to 0.74% at 48h. Finally, about 10% of the initial radioactivity from Endomethasone N used to fill the root canal was retrieved after 48h in the urine. This study demonstrated that radioactive-HCA from Endomethasone N can diffuse through the apex of the root canal and follow a classical pharmacokinetics. This mouse model shows that radioactive-HCA can diffuse through the apex and do not accumulate in periapical-like tissues and organs.