bio-materials. structure of bio-materials and bio- compatibility structure of bio-materials and bio-...
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BIO-MATERIALSBIO-MATERIALS
STRUCTURE OF BIO-MATERIALS AND BIO-STRUCTURE OF BIO-MATERIALS AND BIO-COMPATIBILITYCOMPATIBILITY
IMPLANT MATERIALSIMPLANT MATERIALS
POLYMERIC IMPLANT MATERIALSPOLYMERIC IMPLANT MATERIALS
TISSUE REPLACEMENT IMPLANTSTISSUE REPLACEMENT IMPLANTS
ARTIFICIAL ORGANSARTIFICIAL ORGANS
Syllabus - ChaptersSyllabus - Chapters
STRUCTURE OF BIO-MATERIALS STRUCTURE OF BIO-MATERIALS AND BIO-COMPATIBILITYAND BIO-COMPATIBILITY
Definition and classification of bio-Definition and classification of bio-materialsmaterials
Mechanical properties, visco Mechanical properties, visco elasticityelasticity
Wound-healing process, Wound-healing process, Body response to implants, Blood Body response to implants, Blood
compatibility.compatibility.
DefinitionDefinition
A biomaterial is a synthetic material A biomaterial is a synthetic material used to replace part of a living used to replace part of a living system or to function in intimate system or to function in intimate contact with living tissuecontact with living tissue
Commonplace examples include Commonplace examples include sutures, needles, catheters, plates, sutures, needles, catheters, plates, tooth fillings, etctooth fillings, etc
Classification of bio-Classification of bio-materialsmaterials
From the point of view of the From the point of view of the problem area which is to be solvedproblem area which is to be solved
By considering the levels of By considering the levels of organisationorganisation
Classification based on Classification based on materialsmaterials
Mechanical properties Mechanical properties
The behavior of the material under The behavior of the material under loadingloading
Two important propertiesTwo important properties STRENGTHSTRENGTH STIFFNESSSTIFFNESS
The load - deformation The load - deformation curvecurve
Determinants of strengthDeterminants of strength
The load that the structure can The load that the structure can sustain before failing sustain before failing Ultimate failure pointUltimate failure point
The deformation it can sustain The deformation it can sustain before failingbefore failing Slope of the curve - Stiffness Slope of the curve - Stiffness
The stress – strain curveThe stress – strain curve(In tension)
Stress Stress σσ Strain Strain εε Young’s modulus E = Young’s modulus E = σσ / / εε
Elasticity of a materialElasticity of a material
A comparisonA comparison
Mechanical properties of Mechanical properties of biomaterialsbiomaterials
Visco elasticity Visco elasticity
ViscoelasticityViscoelasticity
The material is subjected to Constant The material is subjected to Constant load and its response varies with timeload and its response varies with time
Combination of viscous fluid and Combination of viscous fluid and elastic solidelastic solid
Two fundamental responsesTwo fundamental responses CreepCreep Stress relaxationStress relaxation
Creep & Stress relaxationCreep & Stress relaxation
Constant load → rapid initial Constant load → rapid initial deformation → slow (time-deformation → slow (time-dependent) progressively increasing dependent) progressively increasing deformation → till equilibrium is deformation → till equilibrium is reachedreached
Constant deformation → rapid initial Constant deformation → rapid initial stress → slow (time-dependent) stress → slow (time-dependent) progressively decreasing stress progressively decreasing stress