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Dental caries is t%e ma&or cause 'or loss o' teet% in
c%ildren and adults( #t a)ectst%e enamel sur'aces o' teet% in
c%ildren and adults and t%e e*posed root sur'aceso' t%e teet% o'
t%e elderl+( Dental caries is t%e result o' t%e interaction o'
t%e
acteria on t%e toot% sur'ace, t%e dental pla-ue or oral io.lm,
t%e diet andspeci.call+ 'ermenta le car o%+drate components o' t%e
diet, /%ic% are'ermented + t%e pla-ue micro0ora to or1anic acids,
and t%e teet% actin1to1et%er over time( Dental caries /ill occur
onl+ /%en t%e t%ree 'actors arepresent to1et%er and /%en t%e+ act
to1et%er over a su2cient period o' time(
#' t%e di)erent 'actors are considered individuall+, it is possi
le to o tain a etterunderstandin1 o' t%e nature o' t%eir
interactions and %o/ t%ese interactions ma+mani'est as a carious
lesion and, eventuall+, i' not treated eit%er preventativel+or /it%
a restoration, as pain and ultimatel+ in t%e loss o' t%e toot%(
Dental pla-ue is a natural io.lm( T%e num er o' di)erent
acterial species indental pla-ue is not
3no/n, ut sop%isticated molecular iolo1+ studies %ave s%o/n t%at
over 455di)erent species ma+ e identi.ed6 man+ more %ave +et to e
c%aracterised( T%ema&orit+ o' t%ese species %ave not een
cultured in t%e la orator+ usin1 t%ecurrent met%ods 'or acterial
isolation( #t is also /ort%/%ile notin1 t%at t%esemolecular
approac%es %ave demonstrated t%at, 'or e*ample,
Streptococcusmutans, previousl+ reported onl+ to e isolated 'rom
t%e oral cavit+ a'ter t%eeruption o' t%e lateral incisors, is
actuall+ present in t%e mout%, colonisin1 t%e
ton1ue, /it%in a 'e/ mont%s o' irt%( A io.lm is a communit+ o'
microor1anismsattac%ed to a solid sur'ace, /it% t%e acteria
encapsulated in pol+mers derived'rom t%e acteria and e*%i itin1
speci.c io.lm c%aracteristics, includin1increased resistance to
antimicro ials and iocides and t%e production o' novelproteins( An
appreciation o' t%is t+pe o' 1ro/t% %as led to attempts to
developnovel anti7pla-ue strate1ies, /%ic% tar1et t%e in%i ition o'
'unction o' novel
io.lm7speci.c proteins( Dental pla-ue is present on virtuall+
all toot% sur'acesand %as a 1eneral structure /%ere + salivar+ and
some acterial proteins areinitiall+ deposited on t%e enamel sur'ace
to 'orm t%e pellicle and t%e pellicle t%ena sor s 'urt%er acteria(
T%e .rst acteria to ind to t%e toot% sur'ace, t%epioneer or1anisms,
include Streptococcus oralis, Streptococcus san1uinius,
eisseria and 8aemop%ilus species and Actinom+ces naeslundii(
T%ese acteriaare isolated 'rom cleaned toot% sur'aces /it%in 95
minutes o' cleanin1( Follo/in1t%e indin1 o' t%ese acteria, ot%er
or1anisms ind and eventuall+ pla-ue o' 'ullt%ic3ness develops,
partl+ ecause o' acterial indin1 ut primaril+ ecause o'
acterial 1ro/t%( T%e indin1 o' acteria to t%e pellicle and to
ot%er acteria ismediated + speci.c interactions in /%ic% onl+
certain acteria ind tocomponents o' t%e pellicle and onl+ certain
acteria interact( ne o' t%e ma&orand most interactive o' all
t%e acteria in dental pla-ue is Fuso acteriumnucleatum /%ic% inds
to man+ ot%er acteria6 it acts almost as a nucleus 'orpla-ue
'ormation, cross7lin3in1 ot%er/ise non7interactin1 acterial
species( T%ecomposition o' dental pla-ue varies over time( #n
supra1in1ival pla-ue t%e 0ora
ecomes more anaero ic, /it% pi1mented anaero ic rods suc% as
;revotella and
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or1anisms /ere used to assess caries ris3( $onse-uentl+,
considera le researc%/as underta3en to esta lis% /%et%er
Streptococcus mutans /as t%e cause o'caries in %umans( Despite
de.nitive evidence t%at t%is /as t%e case, a num er o'
investi1ations /ere underta3en attemptin1 to develop novel
treatments toeradicate S( mutans 'rom t%e oral cavit+ as a means o'
in%i itin1 caries'ormation( T%e met%ods /%ic% %ave een investi1ated
include:
Vaccine development(
;assive immunisation /it% t%e direct application o' anti7S(
mutans anti odiesdirectl+ on t%e toot% sur'ace(
Replacement t%erapies in /%ic% less cario1enic acteria are
introduced into t%emout% to eradicate t%e more cario1enic S( mutans
strains(
Some o' t%ese approac%es /or3 in la orator+ animal models, and
some eradicate
S( mutans 'or s%ort periods 'rom t%e %uman oral cavit+, ut none
%as +et eens%o/n to e e)ective at reducin1 t%e incidence o' dental
caries in %umans( T%ereasons 'or t%e lac3 o' success are still ein1
determined( #t is, %o/ever, /ellesta lis%ed t%at t%ere is a clear
association et/een t%e num ers andconcentrations o' S( mutans in
pla-ue andCor saliva and t%e dental caries statuso' populations,
and to a lesser e*tent to t%e caries status o' an individual( #t
isalso 3no/n t%at dental caries occurs in t%e a sence o' S( Mutans
and individuals/it% %i1% levels o' S( mutans do not necessaril+
%ave to %ave caries(
