Implant coating using swine bone
Hydroxyapatite targets were exposed to sintering tests with the purpose of improving the biocompatible properties of metallic implants currently used in the market.Manizales, 25 de mayo de 2016 — Agencia de Noticias UN-
Sintering of hydroxyapatite targets. Photos: Andrés Almeida (Unimedios) and Paola Andrea Forero Sossa.
Applications of this material are diverse and highly used in medicine and have the property of serving as a superficial coating for orthopedic and dental implants.
This project was carried out by Universidad Nacional de Colombia (UNal) in Manizales, Physics Engineer and Sciences Physics master’s candidate Paola Andrea Forero Sossa at the Plasma Physics Laboratory and coordinated by Professor Elisabeth Restrepo Parra.
“In this research project we produced high quality hydroxyapatite at low cost; we also sintered targets which preserve the properties of the material, enabling future manufacturing of biocompatible coatings for metallic implants such as surgical steels in order to improve their useful life and the quality of life of patients,” said Forero.
Hydroxyapatite (HAp) is the main inorganic constituent of bone and dental tissue. For this reason this compound has been used as bioactive material and part of the biomaterial components used for bone reparations or substitutions.
Hydroxyapatite was obtained from swine femur bone with slaughtering age of approximately six months. The bone undergoes a deproteinization process which consists of removing all organic matter. For this it was cooked in order to remove most of the lipid membrane and tissue; later it was crushed to eliminate the bone marrow.
Once clean the bone chips were grounded in ball grinder obtaining a grain size powder of approximately 38 microns.
The powder obtained was compacted with a universal press and heated to temperatures between 800º and 1,200º C (1,471º and 2,192º F) with the purpose of studying its behavior.
The hydroxyapatite powder was compacted in a press applying 100 MPa, of pressure (11 kilo newtons) and using a 13mm internal diameter compacting element.
To manufacture the tablet they first filled the compacting matrix and exerted pressure afterwards. They finally obtained a 13mm diameter and 2mm thick tablet.
Targets were structurally, compositionally and morphologically characterized. UNal-Medellín helped to process the morphological analysis.
The biocompatible study which validates use of a material as implantable is currently being developed with support of the Universidad Autónoma de Manizales.
“In previous projects which compared the physical and chemical properties between swine bone and synthetic hydroxyapatite (vastly registered in scientific literature), the natural material developed at the Plasma Laboratory has better properties than the synthetic material, because it is more resistant to temperature, maintains its chemical structure and the impurities better match those of human bones,” said Forero.
This project is one of the contributions developed by UNal-Manizales with the purpose of not only improving the properties hydroxyapatite but also to contribute to bone repair or substitutions.(Por: Fin/JDMP/MLA/APBL