Composites of amorphous calcium phosphate and poly(hydroxybutyrate) and poly(hydroxybutyrate-co-hydroxyvalerate) for bone substitution: assessment of the biocompatibility

Composites of amorphous carbonated apatite and poly-(R)-3-hydroxybutyrate (PHB) and poly-(R)-3-hydroxybutyrate-co-(R)-3-hydroxyvalerate (PHBHV), respectively, were studied by pH monitoring upon immersion in water and by long-term osteoblast culture. For comparison, α-tricalcium phosphate (α-TCP), one glass ceramic (GB 9N), and one bioglass (Mg 5) were subjected to the same experiments. Excellent cell proliferation was found on the composite of calcium phosphate with PHB and on the reference materials (α-TCP, glass ceramic, bioglass). In contrast, cell death was observed repeatedly on the composite with PHBHV. A composite of amorphous calcium phosphate and PHB appears to be well suited as slowly biodegradable bone substitution material.