Title of article :
Effect of Polymerization Time and Home Bleaching Agent on the Microhardness and Surface Roughness of Bulk-Fill Composites : A Scanning Electron Microscopy Study
Author/Authors :
Donmez, Nazmiye Department of Restorative Dentistry - Faculty of Dentistry - Bezmialem Vakif University - Istanbul, Turkey , Özduman, ZümrütCeren Department of Restorative Dentistry - Faculty of Dentistry - Bezmialem Vakif University - Istanbul, Turkey , Fildisi, MehmetAli Department of Restorative Dentistry - Faculty of Dentistry - Bezmialem Vakif University - Istanbul, Turkey , Özlen, RümeysaHatice Department of Restorative Dentistry - Faculty of Dentistry - Bezmialem Vakif University - Istanbul, Turkey , Dalkilic, Evrim Department of Restorative Dentistry - Faculty of Dentistry - Bezmialem Vakif University - Istanbul, Turkey , Kazak, Magrur Bahcesehir University - School of Dental Medicine - Restorative Dentistry Department - Istanbul, Turkey
Abstract :
Theaim of this study is to evaluatethemicrohardnessandsurfaceroughness of two different bulk-fillcompositespolymerizedwithlight-curingunit (LCU) with different polymerization times befor eandaftertheapplicationofahomebleachingagent.Materials-Methods. Forbothmicrohardnessandsurfaceroughnesstests,6groupswerepreparedwithbulk-fillmaterials (SonicFill,FiltekBulkFill) accordingtodifferentpolymerizationtimes (10,20,and30s). 102specimenswerepreparedusingTeflonmolds (4mmdepthand5mmdiameter) andpolymerizedwithLCU.30specimens (n=5) wereassessedformicrohardness.Beforehomebleachingagentapplication,thebottom/top (B/T) microhardnessratiowasevaluated.Afterbleachingagentapplication,themicrohardnessmeasurementswereperformedontopsurfaces.Roughnessmeasurementswereperformedin72specimens (n=12) beforeandafterbleachingapplication.Additionally,forSEManalyses,twospecimensfromalltestedgroupswerepreparedbeforeandafterbleachingagentapplication.ThedataB/Tmicrohardnessratiobeforebleachingwasanalyzedbytwo-way ANOVA and Tukey’sHSDtest. Thedatafromthetopsurfaceofspecimens’microhardnessbeforeandafterbleachingwereanalyzedusingWilcoxonsigned-ranktest,Kruskal-Wallis,Mann-WhitneyUtests.ThedatafromsurfaceroughnesstestswerestatisticallyanalyzedbymultivariateanalysisofvarianceandBonferronitest (p<005). Results.TheB/Tmicrohardnessratioresultsrevealednosignificantdifferencesbetweengroups (p>005). Comparingthemicrohardnessvaluesofthecomposites’topsurfacesbeforeandafterbleaching,asignificantdecreasewasobservedexclusivelyinFB30s (p<005). Nosignificantdifferencesinsurfaceroughnessvalueswereobservedwhenthegroupswerecomparedbasedonbulk-fillmaterials (p>005) whilethepolymerizationtimeaffectedthesurfaceroughnessoftheSF20sandSF30sgroups (p<005). Afterbleaching,surfaceroughnessvaluesweresignificantlyincreasedintheSF20sandSF30sgroups (p<005). Conclusion.Thecliniciansshouldadheretothepolymerizationtimerecommendedbythemanufacturertoensurethedurabilityofthecompositematerialintheoralenvironment.
Keywords :
EffectofPolymerizationTime , HomeBleachingAgent , Microhardness , SurfaceRoughness , Bulk-FillComposites , AScanningElectronMicroscopyStudy , LCU , ANOVA
