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176 Cards in this Set
- Front
- Back
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What is the definition of a biomaterial
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A biomaterial can be deined as a natural or syntheitc materil that is used to supplement or replace the functions ofliving tissues
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List the two gernal types of implants, and give examples of each
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Transeint implants are those which are inteded to reamin in contact with the body for a termporay period of time. Thye then are either removed or resorbed by the body. Examples of transeint implants are sutrues, dressings and fixation devices. Permanent implants are those that are intended to reamin in the body permanentyly. Examples of permanent implants include heart valmves andjoint replacemtn devices.
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What is biocmpatibility?
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The biocompatibility of a material must consider obth the host's respone to a material nad hte physological effect of the environment on the material
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What are the two categories of biocompatibility that are seential in biomaterials
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biologic biocomaptbilty relates ot the reaction of hte host ot the implant. THe material must casue harm ot the host tissue. M
Mechanical biocomatibility realtes to the compatibility between the tproperties of hte material nad its intended funciton. The material msut be able ot perfom in a manner that is favorable to the tissue that it enhancing or replacing. |
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Which cractreistic of a biomaterial or device cna affect the hsot response ot that materio or implant
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The shape of a material or decie can adversely effect hthe hsot respnose for instace a device with sarp corners may be lsess copatbile than a device with smoother contours.
The siae of a materi myay also affect the biological response to amterail or device . For instance a materal may hav eexcellent biocompatibilty in bulk form, but may elcit a server response in particulate form. Finally the surface textrue of ameaterail or dvice may affect the hsot response with tissue sch as bone ashering to atextrued sruvace |
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What is th most commonly used test of mechanical properties of a material
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The tensiole test is themethod most oftnen used to evauste themechanical parperties of a metaerial. With theis technique, amaeterial is tertched at a constant rate, wile the force applied theo the material and elongation fo the material ismeaseured.
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What eaer the defiention sf sterssa nds terain?
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stess idedfined as the raion of applied force to crss-sectional ara. Stain is defined as the ration of change in length to the original length of teh materail specimen.
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What is a stress-streain curve/
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The stress - sterain curve is a graph of stress versus strain. Stress is plotted on the vertical axis or y-axis and the steri plooted ont he horizontal axio or x- axis. Teh stress sterainucrve deipict the change in shape ofr staion of amaterial for a given force or stress
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What are the two major regions on a stress strain curve
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The elastic regiongo fthe stress train curve is the inital linear (steaingt) poritonof the curve. nt theis region deformation occurs but the materail returns to its original shapope oupn removal of the force. The palstic reiong og the stress- strain curve is the noniliear poriton of the urve. Int this region, permanetn (plastc) deformation occurse, and the materil does nto return to its oeriginal shape uopn removal of the force.
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What are the three mjor pionts on a stress - strain curve?
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The yild pint is the point on the sterss-sterain curve where the linerar poriton ends and the nonlinear poriton begins. Itn indicates the point at which elsastic behvior ends and ths subsequeint dformation will be permanent.
The ultimate strenght is the point of maximum stress on the stress strain curve. It is the maximum stress that amatreail can withstand. The failure stenght is the piont of stress on the stress-strain curve whre fracture occcurs i. It is also referred oto ast he fractrue sternght. |
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What is the moduulus of elasticity of a material?
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The modulus of elasticity is a materail property related to the slope of hte linear porion of hte stress - sterain curve. It isused to indicate the stiffnes of a meaterial. This property is often used when comparing the mechanical prperties of biomaterails . If hte slpe of stre stress- sterain curve is steep, then the modulus of elasticity is high and the material is realtively stiff. n contrast, a less stiff materail has a low modulus of elasticity.
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What is the difference between the stiffness of a materail and hte stiffness of asdevice?
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The stiffness of a material isan inherent material peroperty, and is constand for each material. The stiffnessof a device can be varied, and depends on the modulus of elasticty of hte material s well as the diminsion f of hte divice.
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What is the ductility of a materail?
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Ductility is a measure of the degree of plastic deformation sustaeined at fractue. ti can be expressed as either percent elongation or percent area reduciton.
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What si the difference between a breittle material and aductile material
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A ductile material experiences a substaneial degree of palstic deformation prior ot felue. Incontrast, a brittle material undergoes very little or no plstic deformation prior ot failure. Brttle materals fracture abefore a high enogh stress to proce plastic defomration is attained.
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What is the toughness of a materail?
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Toghness is ameasure o fthe amount of neergy a materail absorba at the time of ailure. It is repsened by the area under ht estres-sterain curve ufp to the point o fractue.
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What si the harness of amaterial?
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hARNESS IS A MEASURE OF A MATERIAL'S REISTANCE OT LAOCALIZED PLASTIC DFORMANTION. IT REALTES DIERECTLY TO THE WEAR OF A MATERAIL. THE HARNESS OF AMATEAIL I DETERMIND BY MEaSuring the indentation maed in a flat surface ofht ematerial by a nkown force.
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What is ear?
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wear is a process by which mateail is progressivley lost as areuslt of two surfaces slidieng agisnt one antohr. ADhesive wear occurs when two materials in articulation with one another bond together and thendislodge as the materials continue to sleid past each ohtere. AS aresult deris form one material is transfered ot he surface of the other. ABrasive ear occurs when a hard materila tears thrgoh antoher softer more diuctile materail
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What ifatigue failure?
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ftigue failure is amehtod of delaye dfailure reslutng from fulurating ,k or cyclic , stresses. It depneds ont eh combination of the stress applied ande hte number of loading cycles. The greater the streeess, the lower othe number of cycles neede to induce failure. Fatigue failure resutls from crack intitaiton and subsequent propagation fo the crack with each load cyle.
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What is the fatigue limti?
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The fatigue limit is the stress below which fatigue falure will not occure, regardless of the number of loard cycleis. it varis for differnt materils , nd nto all the materils have aftigue limti. The fatigue limit is also called hte nedurance limti.
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What is vicoelasticity?
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Viscoelasticity describe shte viscous and elastic prperties typical fo polymers and biological materils . When a force si appleid ot amterial, the intial deformation is the elastic component of viscoelasticity, and upon removal of the force, the material will reaitn its orignal shape. The viscous component of viscoelasticty is the permanent deofrmaiton that occurs. This permanent deformation is tiem dependent, and increases continuously for as longa the force is applied.
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What is creep?
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Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
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What are the tree categoeis of materials usesd as biomaterails?
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Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
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What are th gerneral charctristic of metls.
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Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
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Name the trheemetals most oftne used as biomaterials
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The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
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What is metal senstibity?
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Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
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Which metal sensitivies are most comon in the human population?
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nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
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What is stess shilding?
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Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
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What can be done t reduce stress shilding in fracure fixation?
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Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
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Wht are the genral charcteristic of plymers?
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polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
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Give examples of plymers that are comonlyh used as biomaterilas.
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Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
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What is creep?
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Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
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What are the tree categoeis of materials usesd as biomaterails?
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Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
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What are th gerneral charctristic of metls.
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Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
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What is creep?
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Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
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Name the trheemetals most oftne used as biomaterials
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The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
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What are the tree categoeis of materials usesd as biomaterails?
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Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
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What is metal senstibity?
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Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
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What are th gerneral charctristic of metls.
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Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
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Which metal sensitivies are most comon in the human population?
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nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
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What is stess shilding?
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Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
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Name the trheemetals most oftne used as biomaterials
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The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
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What can be done t reduce stress shilding in fracure fixation?
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Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
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What is metal senstibity?
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Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
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Wht are the genral charcteristic of plymers?
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polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
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Which metal sensitivies are most comon in the human population?
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nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
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Give examples of plymers that are comonlyh used as biomaterilas.
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Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
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What is stess shilding?
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Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
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What can be done t reduce stress shilding in fracure fixation?
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Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
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Wht are the genral charcteristic of plymers?
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polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
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What is creep?
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Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
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Give examples of plymers that are comonlyh used as biomaterilas.
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Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
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What are the tree categoeis of materials usesd as biomaterails?
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Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
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What are th gerneral charctristic of metls.
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Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
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Name the trheemetals most oftne used as biomaterials
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The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
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What is metal senstibity?
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Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
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Which metal sensitivies are most comon in the human population?
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nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
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|
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What is stess shilding?
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Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
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|
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What can be done t reduce stress shilding in fracure fixation?
|
Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
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Wht are the genral charcteristic of plymers?
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polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
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Give examples of plymers that are comonlyh used as biomaterilas.
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Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
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What is creep?
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Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
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|
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What are the tree categoeis of materials usesd as biomaterails?
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Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
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What are th gerneral charctristic of metls.
|
Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
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Name the trheemetals most oftne used as biomaterials
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The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
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|
|
What is metal senstibity?
|
Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
|
|
|
Which metal sensitivies are most comon in the human population?
|
nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
|
|
|
What is stess shilding?
|
Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
|
|
|
What can be done t reduce stress shilding in fracure fixation?
|
Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
|
|
|
What is creep?
|
Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
|
|
|
Wht are the genral charcteristic of plymers?
|
polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
|
|
|
What are the tree categoeis of materials usesd as biomaterails?
|
Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
|
|
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Give examples of plymers that are comonlyh used as biomaterilas.
|
Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
|
|
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What are th gerneral charctristic of metls.
|
Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
|
|
|
What is creep?
|
Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
|
|
|
Name the trheemetals most oftne used as biomaterials
|
The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
|
|
|
What are the tree categoeis of materials usesd as biomaterails?
|
Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
|
|
|
What is metal senstibity?
|
Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
|
|
|
What is creep?
|
Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
|
|
|
What are th gerneral charctristic of metls.
|
Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
|
|
|
Which metal sensitivies are most comon in the human population?
|
nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
|
|
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What are the tree categoeis of materials usesd as biomaterails?
|
Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
|
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Name the trheemetals most oftne used as biomaterials
|
The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
|
|
|
What is stess shilding?
|
Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
|
|
|
What are th gerneral charctristic of metls.
|
Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
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What is metal senstibity?
|
Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
|
|
|
What can be done t reduce stress shilding in fracure fixation?
|
Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
|
|
|
Name the trheemetals most oftne used as biomaterials
|
The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
|
|
|
Which metal sensitivies are most comon in the human population?
|
nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
|
|
|
Wht are the genral charcteristic of plymers?
|
polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
|
|
|
What is metal senstibity?
|
Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
|
|
|
What is stess shilding?
|
Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
|
|
|
Give examples of plymers that are comonlyh used as biomaterilas.
|
Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
|
|
|
Which metal sensitivies are most comon in the human population?
|
nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
|
|
|
What is creep?
|
Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
|
|
|
What can be done t reduce stress shilding in fracure fixation?
|
Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
|
|
|
What is stess shilding?
|
Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
|
|
|
What are the tree categoeis of materials usesd as biomaterails?
|
Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
|
|
|
What can be done t reduce stress shilding in fracure fixation?
|
Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
|
|
|
Wht are the genral charcteristic of plymers?
|
polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
|
|
|
Wht are the genral charcteristic of plymers?
|
polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
|
|
|
What are th gerneral charctristic of metls.
|
Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
|
|
|
Give examples of plymers that are comonlyh used as biomaterilas.
|
Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
|
|
|
Give examples of plymers that are comonlyh used as biomaterilas.
|
Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
|
|
|
Name the trheemetals most oftne used as biomaterials
|
The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
|
|
|
What is metal senstibity?
|
Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
|
|
|
Which metal sensitivies are most comon in the human population?
|
nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
|
|
|
What is stess shilding?
|
Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
|
|
|
What can be done t reduce stress shilding in fracure fixation?
|
Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
|
|
|
Wht are the genral charcteristic of plymers?
|
polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
|
|
|
Give examples of plymers that are comonlyh used as biomaterilas.
|
Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
|
|
|
What is creep?
|
Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
|
|
|
What are the tree categoeis of materials usesd as biomaterails?
|
Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
|
|
|
What are th gerneral charctristic of metls.
|
Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
|
|
|
Name the trheemetals most oftne used as biomaterials
|
The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
|
|
|
What is metal senstibity?
|
Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
|
|
|
Which metal sensitivies are most comon in the human population?
|
nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
|
|
|
What is stess shilding?
|
Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
|
|
|
What can be done t reduce stress shilding in fracure fixation?
|
Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
|
|
|
Wht are the genral charcteristic of plymers?
|
polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
|
|
|
Give examples of plymers that are comonlyh used as biomaterilas.
|
Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
|
|
|
What is creep?
|
Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
|
|
|
What are the tree categoeis of materials usesd as biomaterails?
|
Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
|
|
|
What are th gerneral charctristic of metls.
|
Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
|
|
|
Name the trheemetals most oftne used as biomaterials
|
The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
|
|
|
What is metal senstibity?
|
Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
|
|
|
What is creep?
|
Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
|
|
|
Which metal sensitivies are most comon in the human population?
|
nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
|
|
|
What are the tree categoeis of materials usesd as biomaterails?
|
Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
|
|
|
What is stess shilding?
|
Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
|
|
|
What are th gerneral charctristic of metls.
|
Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
|
|
|
What can be done t reduce stress shilding in fracure fixation?
|
Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
|
|
|
Wht are the genral charcteristic of plymers?
|
polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
|
|
|
Name the trheemetals most oftne used as biomaterials
|
The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
|
|
|
Give examples of plymers that are comonlyh used as biomaterilas.
|
Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
|
|
|
What is metal senstibity?
|
Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
|
|
|
Which metal sensitivies are most comon in the human population?
|
nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
|
|
|
What is stess shilding?
|
Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
|
|
|
What can be done t reduce stress shilding in fracure fixation?
|
Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
|
|
|
What is creep?
|
Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
|
|
|
Wht are the genral charcteristic of plymers?
|
polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
|
|
|
What are the tree categoeis of materials usesd as biomaterails?
|
Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
|
|
|
Give examples of plymers that are comonlyh used as biomaterilas.
|
Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
|
|
|
What are th gerneral charctristic of metls.
|
Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
|
|
|
Name the trheemetals most oftne used as biomaterials
|
The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
|
|
|
What is metal senstibity?
|
Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
|
|
|
Which metal sensitivies are most comon in the human population?
|
nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
|
|
|
What is stess shilding?
|
Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
|
|
|
What can be done t reduce stress shilding in fracure fixation?
|
Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
|
|
|
Wht are the genral charcteristic of plymers?
|
polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
|
|
|
Give examples of plymers that are comonlyh used as biomaterilas.
|
Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
|
|
|
What is creep?
|
Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
|
|
|
What are the tree categoeis of materials usesd as biomaterails?
|
Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
|
|
|
What are th gerneral charctristic of metls.
|
Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
|
|
|
Name the trheemetals most oftne used as biomaterials
|
The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
|
|
|
What is metal senstibity?
|
Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
|
|
|
Which metal sensitivies are most comon in the human population?
|
nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
|
|
|
What is stess shilding?
|
Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
|
|
|
What can be done t reduce stress shilding in fracure fixation?
|
Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
|
|
|
Wht are the genral charcteristic of plymers?
|
polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
|
|
|
Give examples of plymers that are comonlyh used as biomaterilas.
|
Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
|
|
|
What is creep?
|
Creep is a permanent deformation that occurs over time as a result of an appleid ocnstant stress. ti is amanifestaion fo viscoelsaticity.
|
|
|
What are the tree categoeis of materials usesd as biomaterails?
|
Thre three categores of maerieals used s biomaterils are metals, polymers, nad ceramics
|
|
|
What are th gerneral charctristic of metls.
|
Metals in gernal have a high modulus of elasticity, high mechanical strenght, high yild pint,and areseusceptible ot corrosion. Due ot theri mechnic al propertis metals aer used in applicaton where the device is ubjectoed to high loads.
|
|
|
Name the trheemetals most oftne used as biomaterials
|
The htere most comomnyh used metlas are tiantium alloys, acobalt-chromum alloys, and stinless teels.
|
|
|
What is metal senstibity?
|
Sensitivty is a biological reation that may ocur in response to metal implsnts . Asl oreferred to as a hypersenstibity or allergic reponse, senstivity reuslts form an immune reation to a foreign material. The primary form of sensitvity observed with metal implsnts it he Type IV hypersenstivity. The reactio is a delyae response ande is prmarily a cell-meidated process. the manifestaiton fo metal sensitvity inlcude contact dermatitis anda sustaind infmammatory reaction that result sin osteolyusis.
|
|
|
Which metal sensitivies are most comon in the human population?
|
nickel senstivity is the msot common , with approximately 15% of the poulation exhibitng an allergic respnse ot the metal. Stainles steels contain 13-15.5% nickle. To a lesser exten sensitiives to chmium and cobalt also exist. The sensetivity reaction may be sere enogh to necessitate removal of the devie that is causeing hte response.
|
|
|
What is stess shilding?
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Sterss shilding is aphenomen by which bone mass decreased over na extend period of tiem as reuslt of ht presence of a regid device. IF bone is not subjecto to a sgnificant physiological load , hten the bone mass will slwoly decrese. When a rigid device that has a higher stiffnes than bone such as ametal implnt, is place asdjacent to bone, the applied stess is transferered ot the meatl. aS aresult , th metal effctively sheilds the bone from th stress, and hte bone may undergo atrophy and oss fo mass.
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What can be done t reduce stress shilding in fracure fixation?
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Lwaa rigid or flexible fractue fiaxtion devices are preferred to reduce the effrect o fstress shilding. Materls htat have amodulus of leasticyt similar to tha tof bone are appropriate for less rigidi fractre fixation. Such materials includ polymers nad composites. Metlas may also be used if hte stiffnes of the divce as whonle cn be reuced by varing hte thicknesso fhte fiaxtion palte.
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Wht are the genral charcteristic of plymers?
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polymers , ningeranl have low modules uf elasticyt, low mechanic stennght, undr time depndent degradation and aresucepitble ot abraseion.
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Give examples of plymers that are comonlyh used as biomaterilas.
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Examples of polymer usd as biomaterilas are slicione rubbrees, polmeht methacrylate (PMMA), polethylen and absorbalbe polymers
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what are the absorbable polymers?
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Absorbable polymers are materials that deradeo ver time by ha hydrolys mechanis. The rate of degadation is such ath a, as the device losse strenght the healing tissue is able ot asssume the load. Eventually hte polmer is solubilized or pahocytosed.
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What are some applicatons of absorbably polmers?
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absorbable materails are used ro interanal fixation devices, drug deliver systems, bone fillers, wound care products, tissue caffolds and nerve guidesw
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List several examples of absorbable polmers.
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Absorbable materails inclde polglycolic asce (PGA) polylactic acid (PLA), polyodxanone, and copymers of PGA PLA
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What are hte ideal charactreistics of and absorbalbe fixation device?
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an absorbable fixation devices hould exhibit stability, with good biocompatibilty,
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Waht are the genral chactrisic so fceramics
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ceramics n geral are muc stronger in compression than in tenison they are brittle and hav e good corrosion restiance nad exellent biocmpatibilyt.
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list several exampels of cer
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alumina aerconia carbons hyrdoxya patite
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