Pit - and - Fissure Sealants

1. Prof.d-r R.Kabaktchieva- 2014 Pit-and-FissureSealants

2. Preventive sealing of the fissures - kinds of sealants. Differentialdiagnosisbetween deep sound fissures and dental caries. Indications and contraindication for sealant application in primary and permanent teeth. Methods.Remineralization as a method for primary caries prevention. Contemporary medications and methods.

3. Fluoridesarehighlyeffectiveinreducingthenumberofcariouslesionsoccurringonthesmoothsurfacesofenamelandcementum.Fluoridesarehighlyeffectiveinreducingthenumberofcariouslesionsoccurringonthesmoothsurfacesofenamelandcementum. Fluoridesarenotequallyeffectiveinprotectingtheocclusalpitsandfissures, wherethemajorityofcariouslesionsoccur.

4. Thisresultsinanincreasedproportionintheratioofocclusaltointerproximallesions, eventhoughthetotalnumbermaybeless.

5. Inthelate 1960s andearly 1970s, anotheroptionbecameavailable - theuseofpit-and-fissuresealants. • A liquidresin, morecommonlycalled a dentalsealant.

6. Theplacementofsealantsis a highlyeffectivemeansofpreventingcariouslesions inthepitsandfissuresinbothprimaryandpermanentteeth. • Dental sealant isplacedovertheocclusalsurfaceofthetooth, whereitpenetratesthedeepfissurestofillareasthatcannotbecleanedwiththetoothbrush.

7. 1.Onereasonthat 50% ofthecariouslesionsoccurontheocclusalsurface isthatthetoothbrushbristlehas a greaterdiameterthanthewidthofthefissure. - the fissurecannotbecleanedwiththetoothbrush.

8. Theresinthensolidifies; • Thehardenedsealantpresentsa barrierbetweenthetoothandthehostileoralenvironment.

9. Concurrently, thereis a significantreductionofStreptococcusmutansonthetreatedtoothsurface. Pitsandfissuresserveasreservoirsformutansstreptococci; Therefore, sealingthenichereducestheiroralcount.

10. Sealants present great preventive value when placed correctly and monitored regularly.

11. SealantUseinDentalCare • ThefirstsuccessfuluseofresinsealantswasreportedbyBuonocoreinthe 1960s. • Buonocorefirstdescribedplacingsealants,using a methodtobondpolymethyl-methacrylate (PMMA) tohumanenamelconditionedwithphosphoricacid.

12. Thisconcept, wasrealizedlater,after thedevelopmentof : - bisphenol A-glycidylmethylacrylate (Bis-GMA), - urethanedimethacrylate (UDMA), - triethyleneglycoldimethacrylate (TEGDMA) resins. Theypossessedbetterphysicalpropertiesthan PMMA.

13. Bisphenol A-glycidylmethylacrylateis a mixtureofBis-GMA andmethylmethacrylate; • Nuva-Seal, thefirstsuccessfulcommercialsealant, wasplacedonthemarketin 1972; • Sincethen, moreeffectivesealantshavebecomeavailable; • Theprimarydifferencebetweensealantsisthemethodofpolymerization

14. Some sealants contain fillers. • The products was classified like filled and unfilled sealants.

15. Thefilledsealantscontainmicroscopicglassbeads, quartzparticles, andotherfillersusedincompositeresins. • ThefillersarecoatedwithproductssuchassilanetofacilitatetheircombinationwiththeBis-GMA resin. • Thefillersmakethesealantmoreresistanttoabrasionandwear. • Becausefilledsealantsaremoreresistanttoabrasion, theocclusionshouldbechecked, andthesealantheightmayneedtobeadjustedafterplacement.

16. Theunfilledsealantswearquickerbutusuallydonotneedocclusaladjustment.Theunfilledsealantswearquickerbutusuallydonotneedocclusaladjustment.

17. CriteriaforSelectingTeethforSealantPlacement • A deepocclusalfissure, fossa, orincisallingualpitispresent. • No harmcanoccurfromsealing, whenindoubt, sealandmonitor.

18. A sealantisindicatedif: • Thefossa (shallowdepression) selectedforsealantplacementiswellisolatedfromanotherfossawith a restoration. • Theareaselectedisconfinedtoa fullyeruptedfossa, eventhoughthedistalfossaisimpossibletosealbecauseofinadequateeruption.

19. Theselectedtoothhasanintactocclusalsurfacewhenthecontralateraltoothsurface (surfaceoftoothinoppositearch) iscariousorrestored; teethonoppositesidesofthearchesusuallyareequallypronetocaries. • Anincipientlesionexistsinthepit-and-fissurearea. • Sealantmaterialcanbeflowedovera conservativeclass I compositeoramalgamtoimprovethemarginalintegrity, andintotheremainingpitsandfissurestofurtherpreventrecurrentdecay.

20. a b c Fiveyearsafterplacementof a whitepit-and-fissuresealant - tooth M1 5-yearcontrol: Thefirstpermanentmolar in other side hasbeenrestoredwithtwoamalgamrestorations 15-yearsealant: 15 yearsafterthesingleapplicationof a whitepit-and-fissuresealant - thesametoothasinA.,but 10 yearslater. Ascanbeseen, thesealanthasserveditspurpose, but therehasbeensomelossintheperipheralfissures.

21. Allteethmeetingthepreviouscriteriashouldbesealedandre-sealedasneeded. • Sealantsshouldbeplacedontheteethofchildren and adultsifthereisevidenceofexistingorimpendingcariessusceptibility

22. OtherConsiderationsinToothSelection • Аges 3 and 4 years (preschool) arethemostimportanttimesforsealingtheeligibledeciduousteeth; • Ages 6 to 7 years-forthefirstpermanentmolars; • Ages 11 to 13 years - forthesecondpermanentmolarsandpremolars.

23. Thediseasesusceptibilityofthetoothshouldbeconsidered whenselectingteethforsealants, nottheageoftheindividual.

24. Evaluating of occlusalrisk • Relyon professional judgment, basedontheseverityofthecariesactivityindicators: - numberof "sticky" fissures, - levelofplaqueindex, - numberofincipientandovertlesions, - microbiologictestindications.

25. Combiningsealantplacementand regularfluorideexposurewouldsavemanyschooldays, dentaltreatment and wouldachievebetterdentalhealth.

26. A sealantiscontraindicatedif: • Patientbehaviordoesnotpermituseofadequatedry-fieldtechniquesthroughouttheprocedure. • Anopen, frank, cariouslesionexistsonthesametooth. • Cariesexistonothersurfacesofthesametoothinwhichrestorationwilldisruptanintactsealant. • A largeocclusalrestorationisalreadypresent.

27. PolymerizationofSealants • Thecommonsealantis a liquidresincalled a monomer(a moleculethatcanbeboundtosimilarmoleculestoform a polymer, whichcontainstwoormoremonomers). • Whenthecatalystactsonthemonomer, repeatingchemicalbondsbegintoform, asthehardeningprocess - polymerizationproceeds. • Finally, theresultanthardproductisknownas a polymer.

28. Twomethodshavebeenusedtocatalyzepolymerization Thefirstmethodislightcuringwiththeuseof a visiblebluelight, • Тhelight-curedsealantscontain a catalyst, suchascamphoroquinone, whichisplacedinthemonomer. • Thecatalystissensitive and whenthemonomerisexposedtothevisiblebluelight, polymerizationisinitiated.

29. Thesecondmethodisself-curing, inwhich a monomerand a catalystare mixedtogethertoinducepolymerizationwithouttheuseof a lightsource; • synonymsforthisprocessarecoldcure, autopolymerization, andchemicalactivation.

30. Infirst-generationsealants, polymerizationwasinitiatedbyultravioletlight; • Second-generationsealantswereautopolymerized, • Third-generationsealantsusedvisiblebluelight. • Fourth- andfifth-generationsealantsadded a stepinwhichdental-bondingagentswereusedas a primerbeforethesealantswereplaced. • Sixth-generationsealantsuse a self-etchingprocess. • Lessfrequently, glassionomercementisusedas a dentalsealant.

31. Light-emittingdiode (LED) curingunitfordirect, intraoralexposure.

32. TypesofSealantsGlassIonomerCementSealants • Glassionomercementshavebeenusedasdentalsealants. • Тheydonothavethesameeffectiveretentionratesasthoseofconventionalsealants.

33. Fluoride-ReleasingSealants • Becausefluorideuptakeincreases theenamel'sresistancetocaries, theuseof a fluoridatedresin-basedsealantmayprovideanadditionalanticariogeniceffectifthefluoridereleasedisincorporatedintotheadjacentenamel.

34. Fluorideisaddedtosealantsbytwomethods: • Thefirstisbyadding a solublefluoridetotheunpolymerizedresin. • Thefluoridecanbeexpectedtoleachoutover a periodoftimeintotheadjacentenamel. Eventuallythefluoridecontentofthesealantshouldbeexhausted, butthecontentoftheenamelgreatlyincreased.

35. Thesecondmethodofincorporatingfluorideisbytheadditionofanorganicfluoridecompoundthatischemicallyboundtotheresintoformanion exchange resin. • Whenfluorideislowinthesaliva, fluoridewouldbereleased, • Whenthefluorideintheenvironmentishigh, itshouldbindtotheresintoforma reservoirforfluoridereleaseandrecharge.

36. Fluoride-releasingsealantshaveshownantibacterialpropertiesaswellas a greaterartificialcariesresistancecomparedwith a non-fluoridatedsealant. • Fluoridatedsealantshavealsodemonstrated a caries-inhibitingeffect, with a significantreductioninlesiondepthinadjacentsurfaceenameland a reductioninthefrequencyofwalllesions. • However, recentreviewsrevealedthat, comparedwithresin-basedsealants, fluoride-containingsealantshave a poorretentionrateafter 48 months;theyalsohavenotproventoactas a fluoridereservoirwithlong-termreleaseoffluorideintotheoralenvironment.

37. ColoredVersusClearSealants • Bothclearandcoloredsealantsareavailable. • Theyvaryfromtranslucenttowhite, yellow, andpink. • Thecoloredproductspermit a morepreciseplacementofthesealant. • Retentioncanbemoreaccuratelymonitoredbyboththepatientandtheoperatorplacingthesealant.

38. Somecliniciansprefertheclearsealants, becauseitispossibletoseeunderthesealanttodetectif a cariouslesionisactiveoradvancing.

39. RequisitesforSealantRetention Forsealantretentionthesurfaceofthetoothmust • (1) have a maximumsurfacearea, • (2) havedeep, irregularpitsandfissures, • (3) beclean, • (4) beabsolutelydryatthetimeofsealantplacementanduncontaminatedwithsalivaresidue.

40. IncreasingtheSurfaceArea • Sealantsdonotbonddirectlytotheteeth. • Theyareretainedmainlybyadhesiveforces.

41. Toincreasethesurfacearea, whichinturnincreasestheadhesivepotential, toothconditioners(alsocalledetchants), whicharecomposedof a 30 to 50% concentrationofphosphoricacid, areplacedontheocclusalsurfacepriortotheplacementofthesealant. • Theetchantmaybeeitherinliquidorgelform. • The geliseasiertoapplyandeasiertoremove.

42. Toothafteretchantisplaced. When a toothisetched, itappearschalkywhite.

43. Pit-and-FissureDepth • Deep, irregularpitsandfissuresoffer a muchmorefavorablesurfacecontourforsealantretentioncomparedwithbroad, shallowfossae. Anelectron-scanningmicroscopeviewofthedeeppitsandfissuresoftheocclusalsurfaceof a molar.

44. Тhe possibility of caries development is increased when the fissure depth and slope of the inclined planes is increased • Thus, asthepotentialforcariesincreases, sodoesthepotentialforsealantretention.

45. Surfacecleaning • Тhecleaningpreferenceseitherbyacidetchingorothermethods- allstains, deposits, debris, andplaqueshouldberemovedfromtheocclusalsurfacebeforeapplyingthesealant.

46. Usuallytheacidetchingaloneissufficientforsurfacecleaning. • Othermethodsusedtocleanthetoothsurfacepriortoplacingthesealantincluded, - air-polishing, - use of hydrogenperoxide, • polishingwithpumice, • brushingwith a non-fluoridatedtoothpaste, • useoflaser.

47. Theuseofanair-polisherhasproventothoroughlycleanandremovesresidualdebrisfrompitsandfissures.Theuseofanair-polisherhasproventothoroughlycleanandremovesresidualdebrisfrompitsandfissures. • Hydrogenperoxidehasthedisadvantagethatitproduces a precipitateontheenamelsurface. • Comparisonofacidetchingwithlaseralonedidnotdemonstrateanysignificantdifferenceofsealantretentionormicroleakage.

48. Cleaningteethwiththenewerprophylaxispasteswithorwithoutfluoride (NuPro, Topex) wasnotshowntoaffectthebondstrengthofsealants. • Simonsenaccomplishedthemosteffectivesealantlongevitywithoutuseof a priorprophylaxis. • Cleaningthetoothsurfacewithoil-freepumiceisrecommendedforsixth-generationsealantmaterial.

49. SealantRetention • Resinsealantsareretainedbetteronrecentlyeruptedteeththanonteethwith a morematuresurface. !!!!! • Theyareretainedbetteronfirstmolarsthanonsecondmolars, andarebetterretainedonmandibularthanonmaxillaryteeth. • Themandibularteethbeingmoreaccessibleandeasiertosee; also, gravityaidstheflowofthesealantintothefissures. • Sealantsappeartobeequallyretainedonocclusalsurfacesinprimaryandpermanentteeth.

50. Whentheresinsealantflowsoverthepreparedsurface, itpenetratesthefinger-likedepressionscreatedbytheetchingsolution. Theseprojectionsofresinintotheetchedareasarecalledtags Thetagsareessentialforretention. Tags, 30 micron.