Development of bioactive resin modified glass ionomer cement for dental biomedical applications

It would certainly be an advantage of resin-modified glass ionomer cement (RMGIC) if it can possess bioactivity. However, research related to that is still very limited. Hybridization of RMGIC was predicted to increase mechanical properties and resistance to disintegration, and low content of polyacrylic acid induces cement bioactivity. This study investigated the effect of BAG obtained from the CaSiO3-Ca-3(PO4)(2) system on RMGIC bioactivity. BAG samples containing 10%, 15%, and 20% P2O5 (denoted as "CSP10," "CSP15," and "CSP20," respectively) were used to modify RMGIC powder, and apatite wollastonite was used for comparison. Surface bioactivity was assessed using XRD pattern, infrared spectroscopy, and SEM microstructure after specimen immersion in simulated body fluid (SBF). Contents of Ca, P, F, Sr, and Al were measured in the remaining SBF. Cell attachment, proliferation, and differentiation on the RMGIC containing BAG were evaluated and compared with those on the RMGIC without BAG. Sr and Al analyses revealed that the addition of BAG may not influence the matrix stability of the cement. Moreover, the addition of BAG was a positive factor indicating excellent ion exchange in SBF and spontaneous growth of apatite by consuming the Ca and P ions in the surrounding fluid. Osteoblast differentiation was higher on the four types of bioactive cements than on the RMGIC without BAG. The results of these studies provide novel insights into the development of a new generation of osteoconductive biomedical materials.