1 / 13

Ceramic Biomaterials (Bioceramics)

Ceramic Biomaterials (Bioceramics). The class of ceramics used for repair and replacement of diseased and damaged parts of the musculoskeletal system are referred to as bioceramics . OBJECTIVES to examine chemical/physical properties of ceramics

morey
Download Presentation

Ceramic Biomaterials (Bioceramics)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ceramic Biomaterials (Bioceramics) • The class of ceramics used for repair and replacement of diseased and damaged parts of the musculoskeletal system are referred to as bioceramics. • OBJECTIVES • to examine chemical/physical properties of ceramics • to introduce the use of ceramics as biomaterials

  2. Ceramics • (keramikos- pottery in Greek) • Ceramics are refractory polycrystalline compounds • Usually inorganic • Highly inert • Hard and brittle • High compressive strength • Generally good electric and thermal insulators • Good aesthetic appearance

  3. Structure • Ceramic Structure: AmXn ZnS A: metal, +ve CsCl NaCl X: nonmetal, -ve

  4. Types of Ceramics nearly bioinert

  5. Inert Ceramics: Aluminum Oxides (Alumina) • Applications • orthopaedics: • femoral head • bone screws and plates • porous coatings for femoral stems • porous spacers (specifically in revision surgery) • knee prosthesis • dental: crowns and bridges

  6. Alumina • Inertness: • advantage is that it makes material more biocompatible • disadvantage: • nonadherent fibrous membrane at the interface. • interfacial failure can occur, leading to implant loosening

  7. Inert Ceramics: Zirconia, ZrO2 • zirconium; named from the Arabic, zargun = gold color • Fabrication: • Obtained from the mineral zircon • Addition of MgO, CaO, CeO, or Y2O3 stabilize tetragonal crystal structure (e.g. 97 mol%ZrO2 and 3 mol%Y2O3) • Usually hot-pressed or hot isostatically pressed • Applications: • orthopaedics: femoral head, artificial knee, bone screws and plates, favored over UHMWPE due to superior wear resistance • dental: crowns and bridges

  8. Biodegradable Ceramics: Calcium Phosphates • Almost all bioresorbable ceramics are variations of calcium phosphate • Uses • repair material for bone damaged trauma or disease • void filling after resection of bone tumours • repair and fusion of vertebrae • repair of herniated disks • repair of maxillofacial and dental defects • ocular implants • drug-delivery

  9. Biodegradable Ceramics: Calcium Phosphate • Structure resembles bone mineral; thus used for bone replacement • Coating of metal implants to promote bone ingrowth • Different forms exist depending on Ca/P ratio, presence of water, impurities and temperature

  10. Bioactive Ceramics: Glass Ceramics • Bioactive: capable of direct chemical bonding with the host biological tissue • Glass: • an inorganic melt cooled to solid form without crystallization • an amorphous solid • possesses short range atomic order  BRITTLE! • Glass-ceramic is a polycrystalline solid prepared by controlled crystallization of glass  LESS BRITTLE

  11. SiO2 B C A D CaO Na2O Bioactive Ceramics: Glass ceramics A: Bonding within 30 days B: Nonbonding, reactivity too low C: Nonbonding, reactivity too high D: Bonding

  12. Classification based on tissue attachment

  13. Mechanical Properties CHEE 340

More Related