Student ID: BEBEIU19032
ASSIGNMENT1
1. Based on type of materials, how many classes of biomaterials are there? What are their names?
Biomaterialsgaregmaterialsgoriginatedgfromgnaturegorgthroughgsyntheticgprocessgthatginteractgwithglivinggtissue
s,blood,gandgbiologicalgfluidsg[1].gThegbiomaterialsgcangbegusedgbothgforgtherapeuticg(treatment,gstrengthen,re
pairgorgreplacementgofgagbodygpart)gandgdiagnosticg(sensors,gtestinggmodels,ganimalgexperiments)gpurposes[2
].gTheygcangalsogbegdesignedgforgimplantationgorgincorporationgwithgthegbiologicalgsystemsg[3].gBiomaterials
aregdividedgintogtwogtypesgmainlygusedgingthegindustries:ga)gNaturallygderivedgbiomaterials
Ingtissuegengineering,gnaturallygderivedgbiomaterialsgaregmostlygusedgtogreplacegorgrestoregstructuregandgfunct
ionofgimpairedgtissues/organs.gBecausegofgtheirgmicrostructuregconnectiongandgbioactivitygcharacteristic,gthey
havethegabilitygtogsupportgcellglinkage,gmovement,gmultiplicationgandgdivision.gNaturallygderivedgbiomateria
g
lscomposedgofgmanyggroupsgsuchgasgproteingbasedg(collagen,ggelatin,gsilk…),gpolysaccharidegbasedg(cellulo
se,chitin/chitosan,gglucose…)gandgdecellularizedgtissuegderivedg(decellularizedgheartgvalves,gbloodgvessels,li
ver…).gParticularly,gwhengbeinggimplantedgintogthegdamagedgarea,gnaturallygderivedgbiomaterialsgcangimpro
vethegattachmentgandgmigrationgofgcellsgfromgthegenvironment;gtherefor,gincreasegthegECMgformationgandgtis
suecuringg[4].gb)gSyntheticgbiomaterials
Syntheticgbiomaterialsgaregproducedgusinggagvarietygofgprocessinggmethodsgingthegindustries.gTheygareclassifi
edgintogfourgcommongtypes:
Metallicgbiomaterials
Metalsgaregusedgasgbiomaterialsgforgitsgexcellentgelectricalgandgthermalgconductivitygandgmechanicalgproperti
es.“Vanadiumgsteel”g(stainlessgsteel)gwasgthegfirstgmetalgalloygtogsucceedgingmanufacturinggbonegfracturegplat
es,screwsgandgimplantgmaterialsgingsurgicalgfields.gMetalsglikegirong(Fe),gchromiumg(Cr),gcobaltg(Co),gnickelg
(Ni),titaniumg(Ti),gtantalumg(Ta),gniobiumg(Nb),gmolybdenumg(Mo),gandgtungsteng(W)garegmostlygusedgtogm
akealloysgforgimplantsginghumangbodyg[5].gAmonggtheglistedgmetallicgmaterials,gtitaniumgandgitsgalloygaresig
nificantlygnoticeablegingrecentgyearsgingbothgmedicalgandgdentalgfieldsgduegtogthegstandoutgbiogcompatibility,li
ghtness,gbalancegofgmechanicalgpropertiesgandgcorrosiongresistance.gTheygaregmainlygusedgforgimplantsdevice
s,greplacinggfailedghardgtissues,gforginstance,gartificialghipgjoints,gbonegplates,getcgandgalsogdentalgproductssuc
hgasgcrowns,gbridgesgandgdenturesg[6].
Ceramicgbiomaterials
Thegimportancegofgceramicsgisgincreasinggbecausegofgtheirgbiogcompatibility,gcorrosiongresistancegandghardstr
ucture.gThus,gceramicsgareggenerallygusedgforgbonegsubstitutiongorgbonegregenerationgsupportg[7].gInproducin
ggimplantsgingsurgicalgfields,gceramicsgcangfallgintogmanygclassesgasgnonabsorbableg(relativelyginert),bioactiv
egorgsurfacegreactiveg(semiginert)g[8],gandgbiodegradablegorgresorbableg(nonginert)g[9].gChemicalsglikealumin
a,gzirconia,gsiliconegnitrides,gandgcarbonsgareginertgbioceramics.gSomegglassgceramicsgandgdensehydroxyapati
tesgaregknowngasgsemiginertgwhilegcalciumgphosphatesgandgcalciumgaluminatesgaregcalledresorbablegceramics
, .gCaPsgorgsilicagbasedg(bioglassg45S5s),galuminagbasedgcompoundsgaregpopularlygappliedingbiomaterialsgtod
ayg[10].
Polymericgbiomaterials
Syntheticgpolymersgaregpolymersgformedgbyglinkinggmonomergunits,gwithoutgtheganygchangegofgmaterial,gare
consideredgasgadditiongpolymersgorgchainggrowthgpolymers.gTheygaregclassifiedgasgdegradablegandgnondegra
dablegbasedgongthegchemicalgreactivityg[11].gTheghighgmaterialgdesignability,gregulatedgproperties,gandpractic
allygunlimitedgsourcesgsyntheticsgpolymersgexplaingforgtheirgwidespreadgusesgingbiomedicalapplications.gIngc
omparisongtogmetallicgorgceramicgbiomaterials,gthegpolymericgonesgcangeasilygbemanufacturedgtogcreategman
ygshapesg(latex,gfilm,gsheet,gfibers,getc.),gwithgdesiredgmechanicalgandgphysicalpropertiesgatgaffordablegcostg[
12].
a) Nongdegradablegpolymericgbiomaterials
Nondegradablegpolymersg(alsogknowngasgbiostablegorgbiointegrablegpolymers)garegmainlygusedgforgdrugdeliv
erygsystems,gfillings,gorthopedicgimplants,gocularglens,gheartgvalves,gbonegcements,gvascularggrafts,gandtissue
g engineeringgscaffoldsg[13].gTheyghavegmanygadvantagesgsuchgasgeasilygprocessing,gtissue/bloodcompatibilit
y,gbiologicalgstabilitygandgstrength,gandgothergpropertiesgduringgingvivogapplicationgthatgmakegthemmoregusef
ulgasgbiomaterialsgingcomparisongwithgmetalsgorgceramics.gOnegsignificantgfunctiongisgthegabilitygtoovercome
thegproblemsgofgasynchronousgdegradationgwithgtissuegregenerationgandgharmfulgendgproductsgofdegradedgp
g
olymersg[14].gThegmaingtypesgofgnongdegradablegpolymersgconsistgofgpoly(olefins),g
poly(urethanes),gpoly(carbonates),gpoly(siloxanes),gpoly(amides),gpoly(ethers),gpoly(sulphones)gandgcertainty
pesgofgpoly(esters)g[15].
b) Biodegradablegpolymericgbiomatereials
Biodegradablegpolymersgaregthosegwhichgcangbegbrokengdowngundergaerobicgorganaerobicgconditions,gasgares
ultgofgmicroorganism/enzymesgaction.gBiodegradablegpolymericgbiomaterialsgforgbiomedicalgfieldguseshavegi
ncreasedgrespectivelygingthegpastgdecade.gThisgisgbecausegtheygowngtwogmajorgadvantagesgovernonbiodegrad
ablegbiomaterials.gFirst,gtheygdognotgproduceglastinggchronicgforeigngbodygreactionsgsincegthebodygwillggrad
uallygabsorbgthemgandgleavegnogtracesgofgresidualgingthegimplantationgareas.gSecond,gsomegofpolymersghavegt
hegabilitygtogrevivegtissuesgthroughgtheginteractiongofgtheirgbiogdegradationgwithgimmunologiccells.gHence,gb
iodegradablegbiomaterialsgusedgtogcreategimplantsgforgsurgeriesgcangactgasgtemporarygscaffoldgfortissuegregen
eration.gCommonly,gstarchgderivatives,gcellulosegestersglikegcellulose,gacetategandgnitrocelluloseandgtheirgderi
vativesg(celluloid)garegbeinggusedg[16].
Compositegbiomaterials
Compositegmaterialsgrefergtogheterogeneousgcombinationgingmacroscopicgscaleg(largergthangthegatomic),conta
ingtwogorgmoregseparatedgpartsgofgmaterialsgorgphases,gdifferentgingcomposition,gmorphologygandgphysicalpro
perties,gmadegtogproducegspecificgphysical,gchemicalgandgmechanicalgcharacteristics.gReinforcedgplasticssuch
g asgfiberglassgorgnaturalgmaterialsgsuchgasgbonegaregconsideredgasgcompositegmaterials,gbutgalloysgsuchgasg
orgmetalsgsuchgasgsteelgwithgcarbidegparticles