c orrosion of s urgical i mplants university of technology materials eng. department biomaterials...
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CORROSION OF SURGICAL IMPLANTS
University of TechnologyMaterials Eng. Department
Biomaterials And Biomedical Engineering
Biological Environment
Corrosion is one of the major processes that cause problems when metals and alloys are used as implants in the body.Corrosion is the interaction between material and its environment
Tissue–implant corrosion The interactions between the material and the tissues are of prime
importance. Such interactions induce corrosion/ionization of the implanted device.
Corrosion can have two effects.First the implant may weaken and the premature failure will result. The second effect is the tissue
reaction leading to the release of corrosion products from the implant.
Cells adhering to the surface
of a metallic biomaterial
Influences of the presence of
fibroblasts on the corrosion
of metallic biomaterials
M → Mn+ + neO2 + 4e + 2H2O → 4OHˉ
M → Mn+ + neO2 + 4e + 2H2O → 4OHˉ
Click icon to add pictureGeneralized fibrous capsule forming in response to
intramuscularly implanted metal.
The metal dissolves in body over time rendering removal
surgery
Cells in the periprosthesis tissues in the ankle. Counterstained with hematoxylin. (A): Macrophages (arrowheads) facing necrotic masses (N).
(B): Heavy macrophage infiltration in the implant capsule. (C): bone debris (B) surrounded with macrophages. (D): multinuclear foreign body giant cells
(empty arrows) in the implant capsule
Capsule formation around a polydimethylsiloxane implant.
Peri-implant tissue and immune cell reacting of
implant debris
Diagram of the percentage of the uncorroded implant at various time
Infrared microscope spectra of tissue with (red line) and without (blue line) corrosion products. The absorption
bands, which are caused by the corrosion products, are marked with
arrows.
Potentiodynamic polarization
Material: 304 SS, Cobalt based alloy
Implant location: Orthopedic/ Dental alloy
Material: 316 L stainless steel
Implant location: Bone plates and screws
Material: 304SS/316SS, CoCr +Ti6Al4V, 316SS/Ti6Al4V Or CoCrMoImplant location: Oral implants, Screws and nuts
Material: 316 SS, CoCrNiFe Implant location: Bone cement
Material: Ti6Al4V, CoCr, SS Implant location: Ball Joints
Cardiovascular Implants
Corrosion Various Implants
Artificial heart.
Corrosion of stent in bare metal.
Corrodedstents
Corrosion protection
Surface modification
There is a number of methods, which treat the surface of a metal or alloy to provide protection against corrosion like:
Biomimetic Processing. Electrophoretic Deposition (EPD).Glow discharge nitriding.Ion implantation. Thermal spraying.PVD treatments.Laser treatment.
Ion implantation
Hydroxyapatite coatings
Laser nitriding
Hard coatings for orthopaedic implants
Thanks