The modification of biomaterials approved by the Food and Drug Administration could be an alternative to reduce the period of use in humans. Porous bioceramics are widely used as support structures for bone formation and repair. This composite has essential characteristics for an implant, including good mechanical properties, high chemical stability, biocompatibility and adequate aesthetic appearance. Here, three-dimensional porous scaffolds of Al O containing 5% by volume of ZrO were produced by the replica method. These scaffolds had their surfaces chemically treated with phosphoric acid and were coated with calcium phosphate using the biomimetic method simulated body fluid (SBF, 5×) for 14 days. The scaffolds, before and after biomimetic coating, were characterized mechanically, morphologically and structurally by axial compression tests, scanning electron microscopy, microtomography, apparent porosity, X-ray diffractometry, near-infrared spectroscopy, inductively coupled plasma optical emission spectroscopy, energy dispersive X-ray spectroscopy and reactivity. The in vitro cell viability and formation of mineralization nodules were used to identify the potential for bone regeneration. The produced scaffols after immersion in SBF were able to induce the nodules formation. These characteristics are advantaged by the formation of different phases of calcium phosphates on the material surface in a reduced incubation period. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2615-2624, 2018.

The chemical modification of porous ceramic scaffold surfaces with calcium phosphate surges as an alternative to improve the bioactivity to be used as bone grafts. The biomimetic method has been commonly used to modify surfaces of Ti alloys but surges as alternative to modify ceramic biomaterials. Herein, we modified the surface of Al 2 O 3 scaffolds with calcium phosphate minerals and strontium using the biomimetic method. The scaffolds were chemically treated using H 3 PO 4 solution and then immersed in simulated body fluid 5× solution for 14 days. For the incorporation of strontium, they were immersed in an aqueous solution of 100 ppm analytical-grade Sr(NO 3 ) 2 under magnetic stirring. The samples were characterized by scanning electron microscopy, X-ray microtomography, X-ray diffraction, near-infrared spectroscopy, inductively coupled plasma emission spectroscopy, and energy-dispersive X-ray spectroscopy. The biocompatibility and ability to differentiate osteoblasts in vitro were evaluated using human cells. The incorporation of strontium into the phosphate structure was verified. Scaffolds were obtained with high porosity, three-dimensional structures, and the preferential adhesion and maturation of osteoblastic cells, which are essential to promote bone regeneration in vivo. K E Y W O R D Sbioactivity, calcium phosphate, scaffolds, surface modification