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In-vitro evaluation of apical microleakage of two
obturation methods of immature permanent teeth:
orthograde apical plug of Mineral Trioxide Aggregate
and root canal filling combining custom gutta-percha
cone with Calcium Silicate-based sealer
Rami Hamdan, Jerôme Michetti, Claire Dionnet, Franck Diemer, Marie
Georgelin-Gurgel
To cite this version:
Rami Hamdan, Jerôme Michetti, Claire Dionnet, Franck Diemer, Marie Georgelin-Gurgel. In-vitro
evaluation of apical microleakage of two obturation methods of immature permanent teeth: orthograde
apical plug of Mineral Trioxide Aggregate and root canal filling combining custom gutta-percha cone
with Calcium Silicate-based sealer. GIORNALE ITALIANO DI ENDODONZIA, 2017, 31 (2), pp.89
- 95. �10.1016/j.gien.2017.09.001�. �hal-01790450�
ORIGINAL
ARTICLE/ARTICOLO
ORIGINALE
In-vitro
evaluation
of
apical
microleakage
of
two
obturation
methods
of
immature
permanent
teeth:
Orthograde
apical
plug
of
mineral
trioxide
aggregate
and
root
canal
filling
combining
custom
gutta-percha
cone
with
calcium
silicate-based
sealer
Valutazione
in
vitro
della
infiltrazione
apicale
di
due
metodi
di
trattamento
degli
apici
immaturi:
chiusura
ortograda
con
apical
plug
e
MTA
e
chiusura
con
coni
customizzati
di
guttaperca
e
sealer
calciuo-silicatico
Bioroot
Rami
Hamdan
a,*
,
Je
´ro
ˆme
Michetti
a,b,
Claire
Dionnet
a,
Franck
Diemer
a,c,
Marie
Georgelin-Gurgel
aaServiced’OdontologieConservatrice-Endodontie,Faculte´ deChirurgieDentaire,ToulouseandtheCHUde
Toulouse,3ChemindesMaraıˆchers,31400Toulouse,France
bIRIT—UMRCNRS5505,Avenuedel’e´tudiant,31400Toulouse,France c
InstitutCle´mentAder(ICA,FRECNRS3687),3RueCarolineAigle,31400Toulouse,France Received14May2017;accepted25July2017
Availableonlinexxxxxx
PeerreviewunderresponsibilityofSocieta` ItalianadiEndodonzia. * Correspondingauthor.
E-mail:ramihamdan18@hotmail.com(R.Hamdan),jerome.michetti@gmail.com(J.Michetti),claire.dionnet65@orange.fr(C.Dionnet),
franck.diemer@wanadoo.fr(F.Diemer),ericetmarie.gurgel@sfr.fr(M.Georgelin-Gurgel). Availableonlineatwww.sciencedirect.com
ScienceDirect
jo u rn al ho m e p ag e: ww w. el s ev i e r.c o m /l o ca t e/ gi e
http://dx.doi.org/10.1016/j.gien.2017.09.001
1121-4171/ß2017Societa` ItalianadiEndodonzia.ProductionandhostingbyElsevierB.V.ThisisanopenaccessarticleundertheCCBY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).
Introduction
Completesealingoftherootcanalsystemwithabiological inertmaterialisessential1topreventthere-infectionofthe rootcanalwhichisamajorfactorinfluencingthetreatment outcome.2 Root canal filling of immature teeth with thin dentinalwallsandopenapicesneedsaparticular manage-ment;itistechnicallydifficulttocontrolthecompactionof therootfilling material.3Conventionalrootcanalfillingof
theimmatureteethwithgutta-perchaisnotadequateasit doesnotreinforcetheremainingroot.4,5
In theliterature, severaltherapeuticmethods are pro-posedto solvethisproblem:partialpulpotomy, revascular-ization, apexogenesis and apexification.6 Apexification is amethodtoinduceacalcifiedbarrierinarootwithanopen apexorthecontinuedapicaldevelopmentofanincomplete root in teeth with necrotic pulp.7 After apexification, the tooth is usually sealed with a root canal sealer and
KEYWORDS Apexification; Customgutta-percha cone; Openapex; Tricalciumsilicate cement. PAROLECHIAVE MTA.BIOROOT; Sigilloapicale; Tecnicaortograda; Apiciimmature; Tricalcio-silicati. Abstract
Aim: Theaimofthis studywastoassesswhetheran obturation,combiningacustom gutta-perchaconewiththeBIOROOTTM-RCSsealer,displayssimilarsealingqualitytotheorthograde apicalplugsofMTACAPS1
inimmatureteethwithirregularwideapices.
Methodology: Thirty-fourimmaturepermanentpremolarswithapicaldiametervaryingbetween (1—3mm)werechosenforthisstudyandweredividedintotwogroups.Theywereimbeddedinwet sponge,whichsimulatedtheperiapex.Inthefirstgroup;5mmorthogradeplugsofMTA wereplaced usinganappropriateplugger.Inthesecondgroup;acustomgutta-perchaconewasfabricatedand usedforrootcanalfillingwiththeBIOROOTTM-RCSsealer.Thespecimenswerestoredat378Cand 100%humidityduringfiveweekstoallowthecompletesetofthefillingmaterials.Theapicalleakage wasevaluatedusingadyepenetrationtestwith50%-weightsilver-nitrate.Theteethwerethen embeddedinatransparentresinandsectionedtransversallyat1and3mmfromtheapex.Theslices wereexaminedunderopticalmicroscopeandweregivenscoresfrom(0)to(4).Whenscoringaslice wasdifficult,spectroscopyforenergydispersionusingascanningelectron-microscopewasusedto confirmthescore.TheresultswerecomparedusingtheFishertestwithp<0.05.
Results: Silver-nitratewasfoundinbothgroupsinallslicesat1mm.At3mm,thedifferenceof micro-leakagewasnotsignificant.
Conclusions: Thecustomgutta-perchaconecombinedwithBIOROOTtm-RCSsealerdisplayssimilar leakageresistancetotheorthogradeMTAplugs.
ß2017Societa` ItalianadiEndodonzia.ProductionandhostingbyElsevierB.V.Thisisanopenaccess articleundertheCCBY-NC-NDlicense(http://creativecommons.org/licenses/by-nc-nd/4.0/).
Riassunto
Obiettivi: Loscopo delpresentestudioe` statovalutarelecapacita` di sigillomarginaledel BIOROOTTM-RCSsealerutilizzatoincombinazioneconunconodiguttapercacustomizzatoedi confrontarloconilsigilloottenutoconlatecnicadichiusuraortogradaconilsistemTCAPS1
utilizzandoelementiconapiceirregolareedimmaturo.
Materiali e metodi: Trenta quattro premolari permanenti immaturi con diametro apicale variabileda1a3mmsonostatiselezionatiadivisiinduegruppi.Entrambisonostatiimmersi inunaspugnabagnatachehasimulatolaareaapicale.Nelprimogruppoe` stataeseguitaun otturazioneortogradadi5mmconMTACAPSutilizzandounadeguatoplugger.Nelsecondogruppo e
` statofabbricatounconocustomdiguttapercaeapplicatonelcanaleconilsealerBIOROOT.I campionisonostatimantenutia378in100%diumidita` percompletarelareazionediindurimento. Lapenetrazioneapicaledelcolorantee` statavalutataconilnitratodiargentoal50%.Identicosı` trattaticsonostatiinglobatiinunaresinatrasparenteesezionatitrasversalmentea1e3mm dall’apice.Lesezionieranopoivalutatealmicroscopiootticoeadognunaattribuitounoscoreda0 a4.Quandorisultavadifficiledareunoscore,lasezioneeravalutataalmicroscopioelettronicoa scansionecollegatoconunEDS(spettroscopioadispersionedienergia)perconfermareilrisultato. Lavalutazionestatisticae` stataeffettuataconilFishertestalvalorep<0.05.
Risultati: Ilnitratodiargento(ovveroilcolorante)e` statorilevatoinentrambiigruppinelle sezionia1mm.Nellesezionia3ladifferenzanonerasignificativa.
Conclusioni: Latecnicacustom-madeconguttapercaeBIOROOTsealerhadimostratovaloridi penetrazioneapicaledelcolorantealnitratodiargentosimileallatecnicaortogradatradizionale conMTA:
ß 2017Societa` ItalianadiEndodonzia.ProductionandhostingbyElsevierB.V.Cetarticleest publie´ enOpenAccesssouslicenceCCBY-NC-ND( http://creativecommons.org/licenses/by-nc-nd/4.0/)
gutta-percha. Many studies demonstrated the efficacy of calciumhydroxidepastestoformahardapicalbarrier8but thismethodrequiresalongperiodoftreatment(meantime needed12.9month).9Suchanextendedtimeoftreatment
increasesthetoothfracturerisk.10Apexificationwithmineral trioxideaggregateMTAisatrustworthytechniquetomanage openapices3,11,12andisrecommendedbynumerousstudiesto accomplishtheapicalclosing.3,13,14Theregenerative
treat-mentofteethwithpulpnecrosisandincompleteroot forma-tionisbecomingpartofthetherapeuticendodonticarsenalof immatureteeth.Despitethepromisingresultsofmany pub-lishedcasereports,theprotocolofrevitalizationprocedure hasnotbeenestablishedyet.15Theregenerativeprocedures
appear to develop an instructed endodonticrehabilitation insteadofphysiological-liketissueregeneration.16
Numerousinvitrostudieshavetriedtoassesstheabilityof different methodsandmaterialstomanage therootcanal fillingwithimmatureteeth.However,mostofthesestudies wereperformedonsimulatedimmatureapices,i.e.theapex wasenlargedbyusingaGatesGliddendrill,17diamondbur18
or Ni-Ti files.19 Thus, theresulting shapeof thesimulated immatureapexremainsregular.Theshapeirregularitiesof theopenapexininvivosituationsincreasethedifficultyof managingtherootcanalfilling.
New sealing materials based on tricalcium silicate are getting an increased interest in the endodontic research. It was shown that these cements are biocompatible,20,21 ensureagoodrootcanalsealing22,23andincreasetheroot fractureresistance.24 Amajordisadvantage isthe
retreat-ability,thesecementsbecomehardafterthesettinganditis notpossibletoeliminatethecementcompletelybyusingthe conventionalretreatmentmethods.25,26Usingtricalcium sili-catecementwithimmaturetoothcouldbeinteresting con-sideringthereinforcement oftherootstructure,thegood qualityofsealingandthelowriskofextrusionintheperiapex asmanufacturersrecommendtheuseofsingleconeorlateral compaction techniques.Whenused fororthograde obtura-tion, the calcium silicate-based cements showed similar marginaladaptationtotheorthogradeMTAplugswith simu-latedopenapices.19
Recently,Septodont(Saint-MaurDesFosse´s,France)has introduced a new tricalcium silicate sealer named (BIOR-OOTTMRCS).Accordingtothemanufacturer,thiscementis madefrompurecalciumsilicateandismonomer-free ensur-ingzeroshrinkage, containspuremineral formulationthat willnotstainteeth.Itoffersanexcellentadhesiontodentin andto gutta-perchapoints,agreat abilitytosealauxiliary canals dueto its high flowability andhydrophilic behavior thatallowsacontinuoussealinginthepresenceofmoisture. Theobjectiveofthisstudywastoassesswhetheraroot canal filling, combining a fabricated custom gutta-percha conewiththeBIOROOTTMRCScement,displayscomparable sealingquality toorthogradeplugsofMTACAPS1
(Acteon, Pierre Roland, Me´rignac-France) in immature teeth with irregularwideapices.Thenullhypothesistestedinthisstudy isthatthereisnodifferenceinapicalleakagebetweenthese twomethodsusingadyepenetrationtestwithsilvernitrate.
Materials
and
methods
Thirty-four immaturepermanentmaxillaryandmandibular premolars which where extracted for orthodontic reasons
wereselectedforthisstudy.Thecriteriafortoothselection were:wide apex, novisible rootcariesandfractures.The anatomicaldifficultywasevaluatedbymeasuringtheapical diameter by takingphotos of the apices placednext to a millimeterpaperwithacameraCanonEOS600DDigitalSLR equippedwithmacroTamron1
SP90MMF/2.8DiVCUSD1:1. Theteethweredividedintotwogroups(MTAgroupandB.C. group)withrespect to theirmeasuredapicaldiametersto createtwobalancedgroups.27Allteethwerecoatedbytwo coatsoftwodifferentnails polish.The crownsofallteeth were then removed to obtain a standardized length of 15mm.
Theworkinglength(WL)isdeterminedtobeshort0.7mm ofthepointwheretheK-filesize15wasfirstvisiblewitha binocularat16magnifications.Inallspecimens,theroot canalpreparationwaschemicalshapingratherthan mechan-icalshaping.Theteethwereirrigatedwithatleast5mLof 2.5%sodiumhypochloriteand3mLof17%EDTAsolutionand weredriedwithpaperpoints.
Thesampleswereimbeddedinwetspongewhich simu-lated the periapex and prevented the extrusion of filling materialoutoftheapex.28
Ingroup1(theMTAgroup):5mmorthogradeMTAplugs wereplacedinallteeth usingan appropriateplugger.The teethwerethentemporarilyfilledwithamoistpaperpoint andCavit(ESPE,CergyPontoise,France).Twodayslater,the Cavitwasremovedandtheremainingpartofthecanalwas filledwithGC-Fuji-IXGPFast1
(GCCorporation,Japan).
Figure1 (a)Thefabricatedmastergutta-perchacone.(b)The customconeisfittedtotheworkinglength(Controlradiography).
In group 2 (the B.C. group): Anon-standardized gutta-percha cone was fitted to within 3—4mm of the working length. In very wide canals, two non-standardized gutta-perchaconeswereplacedonacoldglassslapandwerethen rolled and merged by another heated glass slap to form onegutta-percha cone.The newcone wasfittedto within 3—4mmof theworkinglength.The apical3—4mm ofthe fabricated cone were immersed in the Eucalypti-Aethero-leum1 solution (Fagron, Rotterdam, Netherlands) for 15s andthe cone was then inserted,with light pressure, into the root canal which was filled with sodium hypochlorite 2.5%.Themaneuverwasrepeateduntilthefabricatedcone wasfittedtotheworkinglength.Thegutta-perchaconewas rinsedandleftinsodiumhypochlorite2.5%forfewminutesto removeanyEucalyptiresidualsandtohardenitssurface.The canalwasflushedwithatleast5mLofsodiumhypochlorite 2.5%for anddriedwith paper points.The BIOROOTTMRCS
cementwaspreparedinaccordancewiththemanufacturers recommendationsandplacedintherootcanalusingthefitted gutta-perchacone(Fig.1).Thecoronalpartofcanalwassealed with GC-Fuji-IXGP Fast1
(GCCorporation,Japan). Radiographs weretakenforallteethaftertherootcanalfilling.Thesamples werethenstoredat378Cand100%humidityforfiveweeksto allowthecompletesetofthesealerandtheMTA.
Apical micro-leakage: Adye penetration test using 50% weightsilvernitratesolutionduringonehour29andinabsence oflightwasexecutedtoallsamplesexceptfortwoteethin eachgroupwhichwererandomlychosentoserveasacontrol
groups.Theteethwerethenrinsedwithdistilledwaterfor 5mintoremoveanytracesofslivernitrate.Allsampleswere thenimmersedinaphoto-developingsolution(Kodak Profes-sionalD-76,Germany)for24hinpresenceoflight.Theteeth werethenwashedindistilledwaterandscaledwithultrasonic hand pieceto eliminateany residuals ofsilver nitrate.All specimenswereembeddedinatransparentpolyesterresin (Neovents,Sainte-Gemme,France)andwerethen transver-sallysectionedat1and3mmfromtheapexusingaslow-speed sawwithwatercooling.Thephotographsofallsliceswere takenusingamicroscope(Leica—WILDM3B)at16 magnifi-cation and a digital camera Canon EOS 600D Digital SLR equipped with macro Tamron1
SP 90MM F/2.8 Di VCUSD 1:1.Thephotographswereevaluatedbytwoexperimented examiners;thedyepenetrationtestwasscored(0,1,2,3,4) when(0%,<25%,25—50%,50—75%,75—100%)respectivelyof the canal circumference were concerned by the leakage of silver-nitrate;score 0 means absenceof leakage,score 4meanscompleteinfiltration(Fig.2).
Scanningelectronmicroscopeanalyses:ScanningElectron Microscopy (JEOL JSM-5310LV) was chosen to confirm the presence/absence of silver-nitrate in the interface mate-rial/dentinorindentaltubulesusingspectroscopyforenergy dispersionEDS(Figs.3and4).
Statisticalanalysis:Scoresat1and3mmwereanalyzed using the Fisher test with (p<0.05). Kappa values were calculatedtoassesstheinter-examinersagreement regard-ingslicesscores.
Figure2 Scoresofthedyetest.(a)Score0:Absenceofleakage.(b)score1:<25%ofcanalcircumferencewereconcernedbythe leakageofsilvernitrate.(c)Score2:25—50%wereconcerned.(d):Score3:50—75%wereconcerned.(e)Score4:completeinfiltration.
Results
Theminimumandthemaximumapicaldiameterswerenearly 1mm andnearly 3mmrespectively.IntheMTAgroup,the Kappavalueswere1at1mmand0.73at3mm.IntheB.C. group,theKappavalueswerenotcalculableat1mmand0.59 at3mm;astrongagreementwasfoundbetweenexaminers. Forthefirstexaminer,thep-valuesbetweentwogroups were1at1mmand0.05at3mm.
For the second examiner, the p-values between two groupswere1at1mmand0.26at3mm.
Nosignificantdifferenceinleakagewasprovedbetween thetwomethods.
Forbothexaminersat1mm,noneoftheslicesoftheB.C. groupobtainedascoreof0whereasonlyonesliceoftheMTA groupobtainedascoreof0.
Discussion
When the rootfilling material canprevent the leakage of smallmolecules,it wouldprobablypreventthepassage of microorganisms.30Adyepenetrationtestusingsliver-nitrate wasusedinthisstudytoevaluatetheapicalleakagesinceit offersclearresultsandthepossibilityoftheSEManalysis.31
Thefluidtransportmethodisasensitivetechnique,andifnot standardized,theprecisionoftheresultsisoperator depen-dent.32 The bacterial leakage model was criticized since
possible microbial leakage pathways can exist and thus resultsareincorrect.33Analyzingmarginaladaptationusing SEMisalso usedtoevaluatetheresistanceto leakage.19,29
However, samples sectioning can possibly shift the filling materialandcancreatehiatus.
Theapicalsealingofbothmethodswasassessedinmore physiologically accurate conditions and not in enlarged apiceswheretheshaperemainsrelativelyregular.The inter-ruptionofradicularedification resultsinalargevarietyof apicalshapes.3Theresultsofthecurrentstudyhighlighta considerable difficulty to manage successfully the ortho-graderootcanalfillingofimmatureteethwithirregularwide apices.Bothmethodsshowedunsatisfyingapicalsealingand thenullhypothesiswasaccepted.Whentheapicaldiameter exceeds1mm,conventionalorthogradeobturationmethods seemtobeunabletopreventtheapicalleakage.
Inthecurrentstudy,silver-nitratewasfoundnearlyinall slices at 1mm whereas at 3mm, a slight superiority was foundin the MTAgroup over theB.C. group. That canbe explainedbythecompactionofMTAwithasuitableplugger, whereas in the B.C. group, no compaction was executed. Thefabricatedcustomgutta-percha conecombinedwitha
Figure3 ScanningElectronMicroscopeanalysisofthisslice.(a)Choosingmultiplepointsofinterest.(b)Choosingthesamepointson theSEMimage.(c)EnergyDispersionSpectroscopyEDSofthepointn87indicatestheabsenceofthedyeinthispoint.Thesame procedurewasrepeatedforallpointsofinterestandthefinalscoregiventothisslicewas0duetotheabsence.
tricalcium silicatesealer (BIOROOTTM RCS) displayssimilar leakageresultstothetrustworthymethodoftheMTAplugs, andcanbeconsideredfortheeverydaypracticeduetoits easinesswherenospecificmaterialsareneeded.
Onlyregenerativeproceduresallowtheradicular edifica-tionto be resumed.Future investigations of regenerative dentistrywouldpossiblyestablishanauthentictreatmentof immatureteethwithwideirregularapices.
Conclusion
Withinthelimits ofthis study,it canbeconcluded thata fabricatedcustomgutta-perchaconecombinedwith trical-ciumsilicatesealerBIOROOTTMRCSdisplayssimilarleakage
resistance to the orthograde MTA plugs and, due to its
easiness,canbetakenintoconsiderationtomanage imma-tureteethwithwideirregularapices.
Declaration
Allauthorshavecontributedsignificantlyandagreewiththe contentofthemanuscript.
This research did not receive any specific grant from fundingagenciesinthepublic,commercial,ornot-for-profit sectors.
Conflict
of
interest
Theauthorsdenyanyconflictofinterest.
Figure4 ScanningElectronMicroscopeanalysisofthisslice.(a)Choosingazoneofinterest1andmultiplepoints2,3,4.(b)Choosing thesamepointsontheSEMimage.(c)EnergyDispersionSpectroscopyEDSofthesepointsindicatesthepresenceofSilveratleastwith point2.
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