title: Synthesis and mechanical behavior of β-tricalcium phosphate/titania composites addressed to regeneration of long bone segments.
abstract: Bioactive tricalcium phosphate/titania ceramic composites were synthesized by pressureless air sintering of mixed hydroxyapatite and titania (TiO2) powders. The sintering process was optimized to achieve dense ceramic bodies consisting in a bioactive/bioresorbable matrix (β-tricalcium phosphate) reinforced with defined amounts of sub-micron sized titania particles. Extensive chemico-physical and mechanical characterization was carried out on the resulting composites, which displayed values of flexural strength, fracture toughness and elastic modulus in the range or above the typical ranges of values manifested by human cortical bone. It was shown that titania particles provided a toughening effect to the calcium-phosphate matrix and a reinforcement in fracture strength, in comparison with sintered hydroxyapatite bodies characterized by similar relative density. The characteristics of the resulting composites, i.e. bioactivity/bioresorbability and ability of manifesting biomimetic mechanical behavior, are features that can promote processes of bone regeneration in load-bearing sites. Hence, in the perspective of developing porous bone scaffolds with high bioactivity and improved biomechanical behavior, TCP/TiO2 composites with controlled composition can be considered as very promising biomaterials for application in a field of orthopedics where no acceptable clinical solutions still exist.
authors.affiliation: Institute of Science and Technology for Ceramics, Via Granarolo 64, 48018 Faenza, Italy. simone.sprio@istec.cnr.it
authors.forename: Simone
authors.initials: S
authors.lastname: Sprio
authors.forename: Stefano
authors.initials: S
authors.lastname: Guicciardi
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Dapporto
authors.forename: Cesare
authors.initials: C
authors.lastname: Melandri
authors.forename: Anna
authors.initials: A
authors.lastname: Tampieri
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry* / Q000494:pharmacology*; D001842:Bone and Bones / Q000187:drug effects / Q000502:physiology*; D002130:Calcium Phosphates / Q000737:chemistry*; D002516:Ceramics / Q000737:chemistry; D060326:Chemistry Techniques, Synthetic; D017886:Durapatite / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D055595:Mechanical Phenomena; D012038:Regeneration / Q000187:drug effects*; D013696:Temperature; D054457:Tissue Scaffolds / Q000737:chemistry; D014025:Titanium / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D002130:Calcium Phosphates; C009495:titanium dioxide; D017886:Durapatite; D014025:Titanium; C018392:tricalcium phosphate