Biomaterials Flashcards
Define prosthetic
an artificial device that replaces a missing body part, which may be lost through trauma, disease, or congenital conditions
Define implant
a medical device placed inside the body to replace/support a missing biological structure
Define Biomaterial
a material intended to interface with biological systems to evaluate, treat, augment, or replace any tissue, organ, or function of the body
Define Biological Material
a material such as bone, skin, or artery produced by a biological system
Define Osseointegration
the formation of a direct interface between an implant and bone without intervening soft tissue
Define Osteoinduction
undifferentiated and pluripotent cells are stimulated to develop into the bone-forming cell lineage
Define Osteoconduction
the process by which bone is directed to conform to a material’s surface
What is the role of osteoblasts and osteocytes?
involved in the formation/mineralization of bone
What is the role of osteoclasts only?
involved in the resorption of bone tissue
Define biocompatible (FDA)
produces no harm to the host
Define biocompatible (Ours)
the ability of a material to perform with an appropriate host response in a specific situation
Define Biomedical material
the broadest category for materials used in or on the surface of the human body
Define thrombogenicity
the tendency of a material to interact with the blood to produce a clot
Define carcinogenicity
A substance that is able to cause cancer usually be damaging the genome or disrupting metabolic processes
Define mutagenicity
the ability to cause genetic damage
Define stress shielding
the interface between bond and an implant with a high modulus begins to deteriorate
Define fatigue failure
micro-defect creates nucleation point that will fracture under repeated loading/unloading
Define aseptic loosening
the failure of the bond between an implant and bone in the absence of infection usually caused by wear debris
Define fretting fatigue
occurs when a foreign body is statically pressed against the surface of the specimen upon which a cyclic stress is being applied
Define tension
pull
Define compression
push
Define shear stress
scissors, slide
Define extensometer
used to measure the change in dimensions of a test sample along the axis of loading
Define proportional limit
highest stress where stress is linearly proportional to strain
Define yield stress
stress which causes the onset of permanent deformation (also called yield strength or elastic limit)
Define ultimate strength
the area under the stress strain curve up to the failure point
Define strain hardening
an increase in stress levels after the yield stress is reached
Define viscoelastic material
show a time-dependent deformation component due to viscous flow within the material
Define Class I Biomedical Device
low to moderate risk to the patient and/or user (elastic bandages, stethoscopes, surgical tools)
Define Class II Biomedical Device
pose a moderate to high risk to the patient and/or user (infusion pumps, surgical drapes, acupuncture needles)
Define Class III Biomedical Device
have a high risk to the patient and/or user (pacemaker, vascular stents, implants)
Define tough
a material that is both strong and ductile (withstand both high stresses and high strains)
Define generation III alloy
Designed to act as temporary structures that can degrade over time allowing native tissue to integrate with the implant and eventually replace it
Ionic bond
a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions
Metallic bond
a type of chemical bonding that arises from the electrostatic attractive force between conduction electrons and positively charged metal ions
Tightly packed cations surrounded by an electron cloud
Allows for good charge transfer that makes metals good conductors of heat and electricity
Covalent bond
a type of chemical bond that involves the sharing of electron pairs between atoms
Sigma bond
the strongest covalent bonds, due to head-on overlapping of orbitals on two different atoms
Pi bond
where two lobes of an orbital on one atom overlap two lobes of an orbital on another atom