Bioactive composite: comparison of ceramic fillers on osteoconductivity and bone-bonding strength

摘要

A study was conducted to compare osteoconductivity and bone-bonding strength of composites (AWC, HAC, TCPC, ABC, ALC, and SGC) each consisting of either apatite and wollastonite-containing glass-ceramic (AW-GC), hydroxyapatite (HA), beta -tricalcium phosphate ( beta -TCP), amorphous phase-containing alumina bead, alpha -alumina, or amorphous fused silica powder as a filler and bisphenol-a-glycidylmethacrylate(Bis-GMA)-based resin as a matrix. Fillerwas added to the compositein 70percent w/w. Each composite polymerized in situ using radical polymerization, which had uncured surface layer. Affinity indices for AWC, HAC, TCPC, ABC, ALC, and SGC calculated from contact microradiogram specimens of rat tibiae 8 weeks post-implantation were 80.0+-14.9, 57.1+-15.3, 29.5+-11.9, 51.0+-10.4, 5.2+-2.5, and 8.4+-5.6 percent (n=12), respectively. Prefabricated and abraded rectangular plates (10x15x2 mm) of each composite were implanted into the tibial metaphyses of rabbits at random and the failure loads were measured by a detaching test 10 weeks after implantation. The failure loads of AWC, HAC, TCPC, and SGC were 3.95+-0.84, 2.04+-0.44, 2.03+-0.65, and 0.00+-0.00 kgf, respectively (n=8). The failure loads of AWC were significantly higher than those of the rest. Results indicate that both AWC and ABC have higher osteoconductivity than HAC and TCPC, and that AWC has superior bone-bonding strength compared to the rest.