Transcript Corrosion of Implants Assis. Prof. Dr. Rana A. Majed

University of Technology
Materials Eng. Department
Biomaterials And
Biomedical Engineering
CORROSION OF
SURGICAL IMPLANTS
Biological Environment
Tissue–implant corrosion
Cells adhering to the surface
of a metallic biomaterial
M → Mn+ + ne
O2 + 4e + 2H2O → 4OHˉ
Influences of the presence of
fibroblasts on the corrosion
of metallic biomaterials
Generalized fibrous capsule
forming in response to
intramuscularly implanted
metal.
The metal dissolves in body
over time rendering removal
surgery
Capsule formation around a
polydimethylsiloxane implant.
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
Peri-implant tissue and
immune cell reacting of
implant debris
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.
Diagram of the percentage of the uncorroded
implant at various time
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: 316 SS, CoCrNiFe
Implant location: Bone cement
Material: 304SS/316SS,
CoCr +Ti6Al4V,
316SS/Ti6Al4V Or CoCrMo
Implant location: Oral implants,
Screws and nuts
Material: Ti6Al4V, CoCr, SS
Implant location: Ball Joints
Cardiovascular Implants
Artificial heart.
Corrosion of stent in bare metal.
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