Bone grafts and biomaterials substitutes for bone defect repair: A review.

Bioceramics of calcium orthophosphates

This review discusses and summarizes the recent developments and advances in the use of biodegradable materials for bone repair purposes. The choice between using degradable and non-degradable devices for orthopedic and maxillofacial applications must be carefully weighed. Traditional biodegradable devices for osteosynthesis have been successful in low or mild load bearing applications. However, continuing research and recent developments in the field of material science has resulted in development of biomaterials with improved strength and mechanical properties. For this purpose, biodegradable materials, including polymers, ceramics and magnesium alloys have attracted much attention for osteologic repair and applications. The next generation of biodegradable materials would benefit from recent knowledge gained regarding cell material interactions, with better control of interfacing between the material and the surrounding bone tissue. The next generations of biodegradable materials for bone repair and regeneration applications require better control of interfacing between the material and the surrounding bone tissue. Also, the mechanical properties and degradation/resorption profiles of these materials require further improvement to broaden their use and achieve better clinical results.

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Biodegradable Materials for Bone Repair and Tissue Engineering Applications

α-Tricalcium phosphate: Synthesis, properties and biomedical applications

Early detection is a crucial element for the timely diagnosis and successful treatment of all human cancers but is limited by the sensitivity of current imaging methodologies. We have synthesized and studied bioresorbable calcium phosphate nanoparticles (CPNPs) in which molecules of the near-infrared (NIR) emitting fluorophore, indocyanine green (ICG), are embedded. The ICG-CPNPs demonstrate exceptional colloidal and optical characteristics. Suspensions consisting of 16 nm average diameter particles are colloidally stable in physiological solutions (phosphate buffered 0.15 M saline (PBS), pH 7.4) with carboxylate or polyethylene glycol (PEG) surface functionality. ICG-doped CPNPs exhibit significantly greater intensity at the maximum emission wavelength relative to the free constituent fluorophore, consistent with the multiple molecules encapsulated per particle. The quantum efficiency per molecule of the ICG-CPNPs is 200% greater at 0.049 ± 0.003 over the free fluorophore in PBS. Photostability based on ...

Near-infrared emitting fluorophore-doped calcium phosphate nanoparticles for in vivo imaging of human breast cancer.

Developments and applications of bioceramics are reviewed Used initially as alternatives to metallic materials in order to increase the biocompatibility of implants, bioceramics have become a diverse class of biomaterials presently including three basic types: bioinert high-strength ceramics; bioactive ceramics which form direct chemical bonds with bone or even with the soft tissue of a living organism; various bioresorbable ceramics which are actively included in the metabolic processes of an organism with predictable results Certain members of the different types of bioceramics are the most bioinert and biocompatible of all known biomaterials A review of the composition, physicochemical properties, and biological behavior of the principal types of bioceramic materials is given, based on the literature and some of our own data The materials include, in addition to classical sintered ceramics, bioglass-ceramics and bioglasses which are similar in composition, properties, and applications Special attention is given to structure as the main physical parameter determining not only the properties of the ceramic materials, but also their reaction with the biomedium The present status of research and development in bioceramics is characterized as a first step in the solution of complex problems at the confluence of materials science, biology, and medicine by the synthesis of “smart materials”

Bioceramics ― Yesterday, Today, Tomorrow

The paper examines the phase interaction in mechanical mixtures of thermostable hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) powders depending on the annealing temperature, initial composition, and particle size with x-ray interpretation of phase changes. It is established that HA transforms into β-TCP through a dehydration reaction during annealing of the mechanical mixtures of HA and β-TCP powders. The dehydration reaction proceeds through interphase activation in which the limiting stage of nucleation disappears. The phase boundaries in the two-phase HA–TCP mixture are more permeable for water vapors than single-phase boundaries owing to their disordered structure.

Decomposition activation of hydroxyapatite in contact with β-tricalcium phosphate

Phase and chemical changes in sintering partially stabilized zirconia

Influence of the method of synthesis on the properties of powders of partially stabilized zirconium dioxide. I. Particle size and perfection of the crystalline structure of the powders

Influence of the method of synthesis on the properties of powders of partially stabilized zirconium dioxide II. Morphology and properties of the surface of the particles and the structure of the pores

V. A. Dubok

Papers

Bioceramics ― Yesterday, Today, Tomorrow

Decomposition activation of hydroxyapatite in contact with β-tricalcium phosphate

Phase and chemical changes in sintering partially stabilized zirconia

Influence of the method of synthesis on the properties of powders of partially stabilized zirconium dioxide. I. Particle size and perfection of the crystalline structure of the powders

Influence of the method of synthesis on the properties of powders of partially stabilized zirconium dioxide II. Morphology and properties of the surface of the particles and the structure of the pores