Fabrication of bioactive hydroxyapatite/bis-GMA based composite via three dimensional printing.

Hydroxyapatite/bis-GMA composites were processed by new technique which comprised three dimensional printing (3DP) of hydroxyapatite and then impregnation by bis-GMA based resin. Two types of composites which used either as-fabricated green 3DP samples or 1,300 degrees C sintered 3DP samples were studied. It was found that both 3DP composites have higher flexural modulus, strength and strain at break than the initial 3DP hydroxyapatite sample. Composites produced from sintered sample has higher hydroxyapatite content, higher density and greater modulus, but lower strength and strain at break than composite produced from green 3DP sample. In vitro toxicity shows that 3DP hydroxyapatite/bis-GMA based composites are non-toxic. Osteoblast cells were observed to attach and attain normal morphology on the surface of composites.