Peer-Reviewed Journal Details
Mandatory Fields
Towler, MR; Kenny, S; Boyd, D; Pembroke, T; Buggy, M; Guida, A; Hill, RG
2006
September
Journal Of Materials Science-Materials In Medicine
Calcium and zinc ion release from polyalkenoate cements formed from zinc oxide/apatite mixtures
Published
()
Optional Fields
IN-VITRO HYDROXYAPATITE CELLS
17
9
835
839
Calcium and zinc ion release from hydroxyapatite-zinc oxide-poly(acrylic acid) (HAZnO-PAA) composite cements into deionised water was investigated as a function of HA content, PAA concentration, PAA molecular weight and maturation time. At any given maturation time, zinc ion release was constant until the HA content was at the maximum loading (60 wt%) resulting in the cement matrix breaking up, allowing exacerbated ion release. The calcium ion release increased with increased HA content in the composite until the maximum loading where the release drops off. Up to this point, the release of both ionic species was proportional to square root time for the initial 24 hour period, indicating that the release is diffusion controlled. In agreement with related data from conventional Glass Polyalkenoate Cements (GPCs), it is the concentration of the PAA, not the molecular weight, that influences ion release from these materials. However, unlike GPCs, the release of the active ions results in a pH rise in the deionised water, more conventionally seen with Bioglass(R) and related bioactive glasses. It is this pH rise, caused by the ion exchange of Zn2+ and Ca2+ for H+ from the water, leaving an excess of OH-, that should result in a favourable bioactive response both in vitro and in-vivo.
0957-4530
10.1007/s10856-006-9843-0
Grant Details