Abstract
This study investigates gelatin influence on calcium phosphate cement (CPC) setting properties. Cements of different compositions were prepared using α-tricalcium phosphate (α-TCP) enriched with a small amount of dicalcium phosphate dihydrate (DCPD), and different gelatin amounts up to 20 wt%. The cements, prepared with a liquid/powder ratio of 0.3 ml/g, were soaked in simulated body fluid (SBF) for different times ≤21 days. The setting reaction of the control cement prepared without gelatin occurred in 7 days, whereas the transformation of the cements at high gelatin content into apatite was almost complete in 2-day aging in SBF. Gelatin presence reduced the total porosity of the cements, and significantly modified their microstructure. The fractured surface of the aged control cement was covered with entangled plate-like apatite crystals, whereas the gelatin cements displayed more compact surfaces, most likely due to the inhibiting effect of gelatin on apatite crystal growth. The microstructural modifications were in agreement with the improvement of the mechanical properties in the aged cements, the compressive strength of which increased linearly as a function of gelatin content, from 2.0 ± 0.8 to 14 ± 1 MPa. (Journal of Applied Biomaterials & Biomechanics 2004; 2: 81–7)