FluorideFluoride

Fluorides and their role Fluorides and their role in clinical dentistryin clinical dentistry

Clinical contextClinical context

The parent of your 9 year old patient The parent of your 9 year old patient has been reading in the paper about has been reading in the paper about the benefits of fluoride and is curious the benefits of fluoride and is curious to find out from you, what fluoride is to find out from you, what fluoride is and how does it work to protect teeth and how does it work to protect teeth

against decayagainst decay? ?

ObjectivesObjectives

Understand the place of fluorides in theUnderstand the place of fluorides in theprevention & treatment of dental cariesprevention & treatment of dental caries..Mechanism of Absorption & MetabolismMechanism of Absorption & Metabolism. .

Occurrence of FluorideOccurrence of Fluoride..Fluoride IntakeFluoride Intake..Mechanism of ActionMechanism of Action..

Sources of Fluoride used in DentistrySources of Fluoride used in Dentistry      Systemic FluoridesSystemic Fluorides

Topical FluoridesTopical Fluorides . . Dental Fluorosis and how to minimise fluorosisDental Fluorosis and how to minimise fluorosis. .

Recommendations regarding prescriptionRecommendations regarding prescription..

Prevention of Dental cariesPrevention of Dental caries

Factors which tip the balance towardsFactors which tip the balance towardsRemineralisationRemineralisation

11 . .FluorideFluoride 22 . .Control of cariogenic foods & increase in cariesControl of cariogenic foods & increase in caries

protective foodsprotective foods33 . .Plaque controlPlaque control

44 . .Saliva stimulation – increasing salivary flowSaliva stimulation – increasing salivary flow ( ( cleansing, flushingcleansing, flushing ,) ,)increasing the pH )buffering(increasing the pH )buffering(..

Presence of high levels of calcium and phosphate ionsPresence of high levels of calcium and phosphate ions..55 . .Fissure sealantsFissure sealants

The major amount of fluoride absorbed The major amount of fluoride absorbed each day is derived from drinking each day is derived from drinking waterwater

97%97% of soluble fluorides in drinking water is of soluble fluorides in drinking water is absorbed regardless of level presentabsorbed regardless of level present

F is normal constituent of the human F is normal constituent of the human body regardless of daily intakebody regardless of daily intake

–blood plasma, saliva, soft tissues maintain a blood plasma, saliva, soft tissues maintain a constant resting level 0.14ppm- 0.19ppmconstant resting level 0.14ppm- 0.19ppm

Sources of fluorideSources of fluoride

11 . .SYSTEMIC FLUORIDE SOURCES –SYSTEMIC FLUORIDE SOURCES –SWALLOW/DRINK/EATSWALLOW/DRINK/EAT Drinking waterDrinking water..

  Food Food - fish, chicken bones, processed foods - fish, chicken bones, processed foods using fluoridated water, infant formulasusing fluoridated water, infant formulas..

Beverages Beverages eg: tea, soft drinks (using fluoridated eg: tea, soft drinks (using fluoridated water), bottled waterwater), bottled water..Dietary supplementsDietary supplements eg. fluoride tablets, fluoride eg. fluoride tablets, fluoride dropsdrops..

Sources of fluorideSources of fluoride

22 . .TOPICAL FLUORIDE SOURCES – APPLIED TOPICAL FLUORIDE SOURCES – APPLIED DIRECTLY/LOCALLY TO SURFACE OF DIRECTLY/LOCALLY TO SURFACE OF TOOTHTOOTH

Fluoridated ToothpasteFluoridated Toothpaste

Fluoride self applied or professionally appliedFluoride self applied or professionally applied

gels, mouth rinses, varnishes, foamsgels, mouth rinses, varnishes, foams..

Mechanisms of action of Mechanisms of action of fluorides – General principlesfluorides – General principles

There are 2 Anti-caries mechanisms ofThere are 2 Anti-caries mechanisms of

fluoridefluoride::

PRE-ERUPTIVEPRE-ERUPTIVE

POST-ERUPTIVEPOST-ERUPTIVE

Pre-eruptive mechanismPre-eruptive mechanism

F is ingested (drinking F water, F tablets, F drops, F is ingested (drinking F water, F tablets, F drops, and accidentally swallowing F toothpasteand accidentally swallowing F toothpaste ) )

& &incorporated into the enamel during its incorporated into the enamel during its formation formation (unerupted teeth)(unerupted teeth)..

Results in the formation of Fluorapatite )FA(Results in the formation of Fluorapatite )FA(

FA critical pH for dissolution = 4.5 compared FA critical pH for dissolution = 4.5 compared with 5.5 for HAwith 5.5 for HA..

Pre-eruptive mechanismPre-eruptive mechanism

As fluoride is incorporated in the dAs fluoride is incorporated in the developing eveloping enamel enamel to form to form Fluorapatite – it Fluorapatite – it increases resistance to increases resistance to demineralisation and thus prevent demineralisation and thus prevent cariescaries . .

Benefits childrenBenefits children..

Post-eruptive mechanismPost-eruptive mechanism

Fluoride from topical sources )F toothpastes Fluoride from topical sources )F toothpastes /gels/mouthrinses( or from drinking water which /gels/mouthrinses( or from drinking water which after ingestion remains in saliva/plaque or after ingestion remains in saliva/plaque or recirculates in salivarecirculates in saliva))

Fluoride acts directly on the surface of the tooth Fluoride acts directly on the surface of the tooth (plaque/tooth surface interface)(plaque/tooth surface interface)

–after the tooth has erupted - during maturation after the tooth has erupted - during maturation phasephase

&&–during demineralisationduring demineralisation..

Post-eruptive mechanismPost-eruptive mechanism

Results in 4 main effectsResults in 4 main effects::

.1.1Enhancement of remineralisationEnhancement of remineralisation

.2.2Lowering of critical pH for demineralisation of Lowering of critical pH for demineralisation of enamelenamel

.3.3Inhibition of bacterial growth and metabolismInhibition of bacterial growth and metabolism

.4.4Inhibition of acid formationInhibition of acid formation

REVIEWREVIEW::

.1.1Fluoride has a role in the prevention of caries Fluoride has a role in the prevention of caries and treatment of cariesand treatment of caries..

22.. Systemic Systemic & topical fluoride & topical fluoride sourcessources

ccanan iiinhibit caries & enhance remineralisationinhibit caries & enhance remineralisation

Via Via bothboth pre and post –eruptive mechanisms pre and post –eruptive mechanisms

Fluorides in oral fluidsFluorides in oral fluids

SalivaSaliva–v low levels 0.019ppmv low levels 0.019ppm

But play important role in remineralisationBut play important role in remineralisation..

PlaquePlaque–level of F in plaque is 50-100 x salivalevel of F in plaque is 50-100 x saliva..

–F in plaque is held in compounds which F in plaque is held in compounds which are in dynamic equilibrium with plaque are in dynamic equilibrium with plaque fluids. It is released under mild acidic fluids. It is released under mild acidic conditions ie: pH drops after bacterial acid conditions ie: pH drops after bacterial acid formationformation..

In SummaryIn Summary

Fluoride works to control early dental caries in Fluoride works to control early dental caries in several ways. Fluoride concentrated in several ways. Fluoride concentrated in plaque and saliva inhibits the plaque and saliva inhibits the demineralization of sound enamel and demineralization of sound enamel and enhances the remineralization )i.e., recovery( enhances the remineralization )i.e., recovery( of demineralized enamel )As cariogenic of demineralized enamel )As cariogenic bacteria metabolize carbohydrates and bacteria metabolize carbohydrates and produce acid, fluoride is released from dental produce acid, fluoride is released from dental plaque in response to lowered pH at the plaque in response to lowered pH at the tooth-plaque interfacetooth-plaque interface..

SummarySummary

The released fluoride and the fluoride present in The released fluoride and the fluoride present in saliva are then taken up, along with calcium and saliva are then taken up, along with calcium and phosphate, by de-mineralized enamel to phosphate, by de-mineralized enamel to establish an improved enamel crystal structure. establish an improved enamel crystal structure. This improved structure is more acid resistant This improved structure is more acid resistant and contains more fluoride and less carbonate and contains more fluoride and less carbonate Fluoride is more readily taken up by Fluoride is more readily taken up by demineralized enamel than by sound enamel. demineralized enamel than by sound enamel. Cycles of demineralization and remineralization Cycles of demineralization and remineralization

continue throughout the lifetime of the toothcontinue throughout the lifetime of the tooth . .