Mineral deposition at dental adhesive resin containing niobium pentoxide

Abstract

The aim of this study was to asses in vitro the potential of methacrylate-based adhesive resins containing niobium pentoxide (Nb2O5) for stimulating phosphate deposition. Adhesive resins were obtained by mixing 50 wt% BisGMA, 25 wt% TEGDMA and 25 wt% HEMA, and Nb2O5 was added on 2.5 or 5 wt% to the resin. Discs 6.5 mm in diameter and 1.5 mm in height of the resin without Nb2O5 and of the resins presenting the oxide were obtained by inserting the resin into a silicon matrix, followed by photo activation. Discs were immersed in simulated body fluid at 36°C for 1, 7 and 28 days, and then their surfaces were examined by Raman spectroscopy. Changes of intensity of the 962 cm−1 peak, related to phosphate bond, over the samples’ surfaces were used to assess the potential of adhesive resins to stimulate phosphate deposition. Experimental groups containing 2.5 and 5 wt% niobium pentoxide presented a phosphate-rich layer deposition over their surfaces after 7 and 28 days of SBF immersion, and this deposition increased over time. Incorporation of 2.5 or 5 wt% niobium pentoxide provides the potential to promote phosphate deposition on methacrylate-based adhesive resins.