Polymer-infiltrated layered silicates for dental restorative materials

Layered porous ceramic used for polymer-infiltrated-ceramic-network materials(PICNs) may be a promising candidate for dental restoration.The effect of sintering temperature of ceramic green bodies on mechanical and optical properties of PICNs is unclear.The purpose was to fabricate PICNs and evaluate their mechanical and optical properties.Polymer-infiltrated layered silicates for dental restorative materials were prepared via infiltrating polymerizable monomers into partially sintered porous silicates and thermo-curing.Bending samples for flexural strength and fracture toughness were fabricated(sample numbers of n=15).Vickers hardness and elastic modulus were measured via nano-indentation(n=10).One-way ANOVA and Weibull statistics were used for statistical analysis.Optical property was characterized by spectral reflectance.Brittleness index was used to characterize the machinability of the materials.Microstructures and phase structures were investigated using scanning electron microscopy(SEM) and X-ray diffractometer(XRD),respectively.Flexural strength of polymer-infiltrated layered silicates varied from 91.29 to 155.19 MPa,fracture toughness ranged from 1.186 to 1.782 MPa·m^1/2,Vickers hardness ranged from 1.165 to 9.596 GPa,and elastic modulus ranged from 25.35 to 100.50 GPa.The formed glass phases at 1200 and 1300℃ showed influences on corresponding optical property,which could be observed from spectral reflectance.A kind of PICNs was fabricated by infiltrating polymerizable monomers into layered porous ceramic networks.Sintering temperature could have dramatic effects on the mechanical and optical properties of porous ceramics and PICNs.These kinds of materials possess similar properties to that of natural tooth and could be used for dental restoration.