Browsing by Author "Belli, Sema"
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Article An Alternative Adhesive Strategy To Optimize Bonding To Root Dentin(Elsevier Science inc, 2011) Belli, Sema; Cobankara, Funda Kont; Ozcopur, Betul; Eliguzeloglu, Evrim; Eskitascioglu, GurcanIntroduction: This study examined the hypothesis that the shear-bond strengths of AH Plus (AH) and Hybrid Root Seal (HRS) to root dentin might be optimized by using a powdered dentin-reinforced bonding procedure. Methods: The surfaces of root halves obtained from extracted human premolars were ground (800-grit silicon carbide paper), treated (5.25% NaOCl 17% EDTA for 5 minutes followed by distilled water) and randomly allocated into two groups according to the sealer and then into three subgroups according to bonding procedure. Dentin particles with a maximum size of 25 mu m were incorporated into the adhesive of Clearfil Liner Bond 2V, and groups were created as follows: no adhesive, adhesive alone, and with powdered dentin reinforced adhesive; 3 x 3 mm high buildups were created using sealer and allowed to set (37 degrees C, 100% humidity, 72 hours). Shear tests were performed (1 mm/min). Data were calculated as MPa and analyzed (two-way analysis of variance, Tukey test). Results: A significant difference was found between the groups (P = .000). Adhesive or reinforced adhesive had a negative effect on the shear-bond strength of AH, but they significantly increased the shear-bond strength of HRS (P = .000). HRS showed a similar bond strength with either adhesive alone or adhesive reinforced with powdered dentin. AH group was characterized by mixed failure, whereas the predominant failure type of the HRS group was cohesive failure within the sealer. Conclusions: Reinforcing adhesive resin with powdered dentin may be considered an alternative for optimizing the bonding of methacrylate-based sealers to root dentin and might affect the shear bond strength. (J Endod 2011;37:1427-1432)Article Are Dentin Posts Biomechanically Intensive?: a Laboratory and Fea Study(Taylor & Francis Ltd, 2014) Belli, Sema; Celik, Kezban; Akbulut, Makbule Bilge; Guneser, Mehmet Burak; Eraslan, Oguz; Eskitaccioglu, GurcanThe goal of this laboratory and finite elemental stress analysis (FEA) study was to compare fracture strength of dentin post (DP) with stainless steel and glass fiber posts. Single-rooted teeth were decoronated and restored with ParaPost (PP), i-TFC (TFC), and DPs (n=10). Resin cores were created and loaded until failure (1.0mm/min). The data were analyzed (ANOVA, Tukey, Chi-Square tests). Three-dimensional FEA models of the posts were created and the stress distributions were calculated using Solid Works/Cosmos works structural analysis program. A significant difference was found among the groups (p<0.001). TFC group showed the highest and the DP group showed the lowest fracture resistance (p<0.001). PP created more stress at the root dentin and inside the post. Restoration of roots with glass fiber and DPs may reduce stresses within the core material and the remaining root. However, a fracture-resistant restoration cannot be achieved by using a DP.Article Conservative Restoration of Severely Damaged Endodontically Treated Premolar Teeth: a Fem Study(Springer Heidelberg, 2011) Eraslan, Oznur; Eraslan, Oguz; Eskitascioglu, Gurcan; Belli, SemaThe aim of this finite element method (FEM) study was to test two different restorative techniques used for construction of severely damaged endodontically treated premolar teeth using Finite Element Stress Analysis Method. In this study, four types of three-dimensional (3-D) FEM mathematical models simulating (1) a sound lower single rooted premolar tooth with supporting structures; (2) a root-filled lower premolar tooth without lingual cusp, restored with resin composite; (3) a root-filled lower premolar tooth without lingual cusp restored with resin composite in combination with a polyethylene fiber which is placed circumferentially to help to create a composite lingual wall; (4) a root-filled lower premolar tooth without lingual cusp restored with resin composite in combination with a glass fiber post, were modeled. A 300-N static vertical occlusal load was applied on the node at the center of occlusal surface of the tooth to calculate stress distributions. Solidworks/Cosmosworks structural analysis programs were used for FEM analysis. The analysis of the von Mises stress values revealed that maximum stress concentrations were located at loading areas for all models. Root dentine tissue, lingual cortical bone, and apical bone structures were other stress concentration regions. There were stress concentration differences among the models at root dentine tissue. Although the distribution pattern was similar with composite resin restored tooth model, highest stress values were observed at root dentine in the model restored with post-and-core. Post structure accumulated more stress on its own body. Stress distribution patterns of sound tooth and fiber-reinforced restoration models were found as similar. The present study showed that the use of post material increased the stress values at root dentine structure while reinforcing the restoration with a fiber decreases stress transmission. Fiber-reinforced restoration provided stress distributions similar to sound tooth.Article Dentinal Tubule Penetration and Dislocation Resistance of a New Bioactive Root Canal Sealer Following Root Canal Medicament Removal Using Sonic Agitation or Laser-Activated Irrigation(Aves Press Ltd, 2020) Ozlek, Esin; Neelakantan, Prasanna; Akkol, Elif; Gunduz, Huseyin; Ucar, Yagmur Arzu; Belli, SemaObjective: To investigate the influence of sonic agitation or laser-activated irrigation techniques on the removal chlorhexidine (CHX) and modified triple antibiotic paste (mTAP) on the sealer penetration depth and dislocation resistance of Guttaflow Bioseal. Methods: Single-rooted mandibular premolars (n=96) were prepared with rotary nickel titanium instruments and randomly divided into two groups (n=48) based on the intracanal medicaments used: Group 1, mTAP; Group 2, CHX gel. After 7 days, the specimens in each group were divided into three subgroups (n=16) based on the supplementary irrigation technique used to remove the medicaments: laser activated irrigation (Er, Cr: YSGG laser, Waterlase MD, Biolase Technology Inc., San Clemente, CA, USA), sonic agitation (EndoActivator, Dentslpy Sirona Endodontics, PA, USA) and syringe-and-needle irrigation (control) techniques. Canals were filled with single matched-taper gutta-percha cone and a calcium silicate-based sealer (GuttaFlow (R) Bioseal, Coltene/Whaledent, Langenau, Germany). At the end of three weeks, sealer penetration was investigated using confocal microscopy (n=6), and dislocation resistance was calculated by measuring the push-out bond strength (n=10). Statistical analysis was performed using three-way analysis of variance (ANOVA) and Tukey post-hoc test (P=0.05). Results: Laser activated irrigation resulted in significantly higher depth of sealer penetration compared to sonic agitation and syringe irrigation (P<0.01). The average sealer penetration depths were recorded as 846.6 mu m, 786.5 mu m and 505 mu m in the Er,Cr:YSGG laser, EndoActivator and control groups, respectively. The mean bond strength obtained in group 3 (syringe-and-needle irrigation) was significantly less than the other groups (P<0.05). The mean values were 9.08 in the Er,Cr:YSGG laser group, 8.44 in the EndoActivator group and 5.08 in the needle group. Conclusion: Er,Cr;YSGG laser irrigation to remove the medicaments was advantageous to other irrigation techniques in sealer penetration and dislocation resistance of the sealer.Article Effect of Cyclic Loading and an Intermediate Material on Microtensile Bond Strengths of a Dual-Cure Resin Cement To Dentin Resin-Coated With All-In Adhesives(Elsevier Taiwan, 2012) Belli, Sema; Ozcopur, Betul; Yesilyurt, Cemal; Akman, Melek; Breslin, Nicholas; Dorsman, GregBackground/purpose: The purpose of this in vitro study was to evaluate the effects of mechanical loading and an intermediate material on microtensile bond-strengths (mu TBSs) of four all-in-one adhesives and a total-etching adhesive system to dentin. Materials and methods: Dentin surfaces of sound human third molars were exposed and treated with Danville Experimental (Danville Materials), G Bond (GC), Clearfil S-3 Bond (Kuraray), AdheSE One (Vivadent), and Prelude total-etch (Danville Materials). Dual-curable resin (Multicore; Vivadent) build-ups were created with and without the use of Prelude Dual/Self Cure Link (Danville Materials). Two subgroups were created (with and without mechanical-loading: 5 x 10(4)[cycles]; 50 N at 0.2 Hz). After storage at 37 degrees C for 1 week, the mu TBS test was performed. Data were calculated (MPa) and statistically analyzed (multivariate analysis of variance and Scheffe's tests). Results: Pre-test failure was observed, and no data were obtained from groups in the absence of Prelude Dual/Self Cure Link, except for the Prelude total-etch group. Prelude total-etch provided significantly higher mu TBSs to dentin than did the other adhesives (P < 0.05). Bond strengths of all tested adhesives were significantly reduced upon application of the loading regimen (P < 0.05). Clearfil S-3 Bond and G Bond provided significantly higher mu TBSs to dentin than AdheSE One and the experimental adhesive (P < 0.05). Conclusion: Mechanical loading significantly decreased the adhesive performance, and Prelude Dual/Self Cure Link increased it for all-in-one adhesives when used with a dual-curable resin. Copyright (c) 2012, Association for Dental Sciences of the Republic of China. Published by Elsevier Taiwan LLC. All rights reserved.Article The Effect of Loading on Μtbs of Four All-In Adhesives on Bonding To Dentin(Wiley, 2009) Belli, Sema; Ozcopur, Betuel; Yesilyurt, Cernal; Bulut, Guenes; Ding, Xingzhe; Dorsman, GregThis in vitro study analyzed the effect of mechanical loading on microtensile bond strength (mu TBS) to dentin of four all-in-one adhesives and compared with a total-etch adhesive system. The tested adhesives were Danville Experimental (an unfilled single-component adhesive containing a proprietary organophosphate and hydrophobic monomers; Danville Materials), G Bond (GC), Clearfil S-3 Bond (Kuraray), AdheSE One (Vivadent), and Prelude Total-Etch (Danville Materials). Dentin surfaces were exposed and composite resin (AP-X, Kuraray) build-ups were created. The samples were divided into two subgroups and the first subgroups were subjected to mechanical fatigue loading (5 x 10(4); 50 Nat 0.2 Hz). Testing was performed after I week using a "nontrimming" mu TBS test at a cross head speed of 1 mm/min. The data was calculated as MPa and statistically analyzed using Multivariate Analysis of Variance. Multiple comparisons were done using t-test. Mechanical loading significantly decreased mu TBS of the tested materials (p = 0.000). Prelude Total-etch showed the highest bond strength values when compared to the tested all-in-one adhesives (p < 0.01). G Bond and Clearfil S-3 Bond showed significantly higher bond strength values than Danville Experimental and AdheSE One (p < 0.01). (C) 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 91B: 948-956, 2009Article Effect of Post-Restoration on Stresses in Premolars With Endodontic-Periodontal Lesion: an Fea Study(Taylor & Francis Ltd, 2017) Belli, Sema; Eraslan, Oguz; Hakki, Sema Sezgin; Eskitascioglu, Murat; Eskitascioglu, GuercanAim: This finite elemental stress analysis (FEA) study was aimed to test the effect of fiber and metal posts on stress distribution in premolar teeth with endodontic-periodontal (EP) lesion. Methodology: Three FEA models representing different EP lesions (primary endodontic disease (PED), PED with periodontal involvement and true-combined) were created. Tooth-model without EP lesion was used as control. The root-canals were assumed as root-filled, restored using glass-fiber or metal posts, resin composite build-up, and ceramic crown. A 300 N load was applied from the palatal surface of the crown with a 135 degrees angle. The SolidWorks/Cosmosworks structural analysis program was used for FEA analysis. Results were presented by considering von Mises criteria. Results: Maximum stress values for PED, PED with periodontal-involvement and true-combined lesions were 2.26, 1.25, 0.74 MPa for glass-fiber post; 2.08, 1.51, 1.18 MPa for metal post, respectively. If there is PED, fiber-post gave an advantage to the tooth at core structure and coronal third of the root. Metal post kept the stress inside its body however caused small, high stress concentrated areas at cervical. When there is PED with periodontal-involvement, metal post forwarded less stress toward the apical while fiber-post saved the coronal structure. In true-combined lesion model, metal post kept the stresses within its body and forwarded less stress toward the remaining root structure and periodontium. Conclusion: EP lesions have an effect on stress distribution therefore the post material selection should be done based on the severity of the lesion. Metal posts might be preferrable since it forwards less stress toward the surrounding periodontal tissues during wound healing.Article Effect of Restoration Technique on Stress Distribution in Roots With Flared Canals: an Fea Study(Quintessence Publishing Co inc, 2014) Belli, Sema; Eraslan, Oznur; Eraslan, Oguz; Eskitascioglu, GurcanPurpose: The aim of this finite element analysis (FEA) study was to test the effect of different restorative techniques on stress distribution in roots with flared canals. Materials and Methods: Five three-dimensional (3D) FEA models that simulated a maxillary incisor with excessive structure loss and flared root canals were created and restored with the following techniques/materials: 1) a prefabricated post: 2) one main and two accessory posts; 3) i-TFC post-core (Sun Medical); 4) the thickness of the root was increased by using composite resin and the root was then restored using a prefabricated post; 5) an anatomic post was created by using composite resin and a prefabricated glass-fiber post. Composite cores and ceramic crowns were created. A 300-N static load was applied at the center of the palatal surface of the tooth to calculate stress distributions. SolidWorks/Cosmosworks structural analysis programs were used for FEA analysis. Results: The analysis of the von Mises and tensile stress values revealed that prefabricated post, accessory post, and i-TFC post systems showed similar stress distributions. They all showed high stress areas at the buccal side of the root (3.67 MPa) and in the cervical region of the root (> 3.67 MPa) as well as low stress accumulation within the post space (0 to 1 MPa). The anatomic post kept the stress within its body and directed less stress towards the remaining tooth structure. Conclusion: The creation of an anatomic post may save the remaining tooth structure in roots with flared canals by reducing the stress levels.Article Effect of Root Filling on Stress Distribution in Premolars With Endodontic-Periodontal Lesion: a Finite Elemental Analysis Study(Elsevier Science inc, 2016) Belli, Sema; Eraslan, Oguz; Eskitascioglu, GurcanIntroduction: Endodontic-periodontal (EP) lesions require both endodontic and periodontal therapies. Impermeable sealing of the root canal system after cleaning and shaping is essential fora successful endodontic treatment. However, complete healing of the hard and soft tissue lesions takes time, and diseased bone, periodontal ligament, and tooth fibrous joints are reported to have an increased failure risk for a given load. Considering that EP lesions may affect the biomechanics of teeth, this finite elemental analysis study aimed to test the effect of root fillings on stress distribution in premolars with EP lesions. Methods: Three finite elemental analysis models representing 3 different types of EP lesions (primary endodontic disease [PED], PED with secondary periodontic involvement, and true combined) were created. The root canals were assumed as nonfilled or filled with gutta-percha, gutta-percha/apical mineral trioxide aggregate (MTA) plug, and MTA-based sealer. Materials used were assumed to be homogenous and isotropic. A 300-N load was applied from the buccal cusp of the crown with a 135 angle. The Cosmoworks structural-analysis program (SolidWorks Corp, Waltham, MA) was used for analysis. Results were presented considering von Mises criteria. Results: Stresses at the root apex increased with an increase in lesion dimensions. Root filling did not affect stress distribution in the PED model. An MTA plug or MTA-based sealer created more stress areas within the root compared with the others in the models representing PED with periodontic involvement and true combined lesions. Conclusions: Stresses at the apical end of the root increase with increases in lesion dimensions. MTA-based sealers or an MTA plug creates more stresses when there is periodontic involvement or a true combined lesion.Article Evaluation of the Effect of Rotary Systems on Stresses in a New Testing Model Using a 3-Dimensional Printed Simulated Resin Root With an Oval-Shaped Canal: a Finite Element Analysis Study(Elsevier Science inc, 2016) Eken, Rahmi; Sen, Ozgur Genc; Eskitascioglu, Gurcan; Belli, SemaIntroduction: This finite element analysis study was aimed at evaluating the effects of rotary systems on stresses in photopolymerized resin root models with oval-shaped canals. Methods: Among the data collected by computed tomographic imaging, a mandibular second premolar tooth with an oval-shaped canal was selected, recorded as Digital Imaging and Communications in Medicine, and transferred to Materialise's Interactive Medical Image Control System software. Three-dimensional modeling was performed to produce photopolymerized resin root models. Root canals were prepared by OneShape (OS; MicroMega, Besancon, France); ProTaper Universal (PTU; Dentsply Tulsa Dental, Tulsa, OK); WaveOne (WO, Dentsply Maillefer, Ballaigues, Switzerland); Mtwo (MT; VDW, Munich, Germany); Twisted File (TF; Kerr Dental, Orange, CA); ProTaper Next (PTN, Dentsply Tulsa Dental), and hand files (HFs) (control). The models were scanned (micro computed tomographic imaging; SkyScan 1174; Kontich, Belgium), finite element analysis models were created, and stresses were calculated under 300-N loading (at a 45 degrees angle and vertically). Results: The maximum stress values were found to be higher when the roots were loaded at an angle. The range of the stress values was PTU > MT > WO > HF > PTN > OS > TF. The stresses were forwarded toward the apical area in the PTN, OS, and TF models. When loaded vertically, the highest maximum stress values were recorded in the WO model. High stress concentrations were observed at coronal, thus less stress was forwarded toward the apical, giving an advantage to the root. The range of the others was as follows: PTN >= PTU > MT > TF > OS >= HF. The TF model showed lower maximum stress values, whereas the HF model showed more homogenous stress distribution. Conclusions: Considering the stress distributions, and stress values within the models, it can be concluded that oval-shaped canals prepared by HFs and WO were less likely to result in root fracture.Article Influence of Powdered Dentin on the Shear Bond Strength of Dentin Bonding Systems(Japanese Soc dental Materials devices, 2012) Eliguzeloglu Dalkilic, Evrim; Genc, Ozgur; Ozcopur, Betul; Belli, Sema; Eskitascioglu, Gurcan; Ozcan, MutluThis study evaluated the effect of different amounts of dentin powder (DP) mixed in Clearfil SE Bond (CSB) or Single Bond (SB) on adhesion to dentin. Human third molars (n=96) were sectioned to expose the mid-coronal dentin and divided into eight experimental groups (n=12 per group), namely, Group 1: CSB, Group 2: CSB+1.5 mg DP, Group 3: CSB+3 mg DP, Group 4: CSB+4.5 mg DP, Group 5: SB, Group 6: SB+1.5 mg DP, Group 7: SB+3 mg DP, and Group 8: SB+4.5 mg DP. Filtek Z250 composite was bonded onto dentin, and all specimens were subjected to shear bond strength test at a crosshead speed of 1 mm/min. Highest bond strength was obtained in Groups 1, 2, and 3 (15.1, 13.5, and 16.4 MPa respectively; p>0.05) and the lowest in Groups 6, 7, and 8 (5.5, 5.6, 4 MPa; p>0.05). DP addition, regardless of amount, adversely affected the bond strength of SB. Bond strength of CSB was not affected when 1.5 or 3 rag of DP was added.Article The Use of Endodontically Treated And/Or Fiber Post-Retained Teeth as Abutments for Fixed Partial Dentures(Springer Heidelberg, 2012) Akman, Serhan; Akman, Melek; Eskitascioglu, Gurcan; Belli, SemaThe purpose of this in vitro study was to evaluate the effect of endodontic treatment with or without fiber-post restorations on the fracture strength of abutment teeth under fixed partial dentures (FPDs). Seventy extracted premolar and canine teeth were used. Groups of fiber-post-retained and root-filled teeth were endodontically treated. The teeth were embedded in an acrylic resin perpendicular to the horizontal plane to create fixed partial dentures. The following groups were created using different abutments: (1) sound (S) canine/S premolar, (2) S canine/endodontically treated (ET) premolar, (3) ET canine/S premolar, (4) ET canine/ET premolar, (5) S canine/fiber-post-restored (FPR) premolar, (6) FPR canine/S premolar, and (7) FPR canine/FPR premolar. Each tooth was prepared for a complete-coverage full-metal crown. Impressions were taken; metal frameworks were fabricated and cemented. The samples were exposed to 5,000 cycles of thermomechanical fatigue and loaded compressively until fracture (2 mm/min). The data were statistically analyzed using (Kruskal-Wallis test, alpha = 0.05). No significant difference was found among the mean fracture strengths of the groups (p = 0.696). There were distinct differences in failure patterns. All of the fracture types were horizontal, and neither vertical nor non-restorable root fractures were recorded. Premolars seemed to be a critical abutment compared to canines when they were sound under FPDs. The percentage of cervical fractures was high in endodontically treated teeth when compared to post-retained groups. In case of post-debonding, the abutment fracture did not occur. When root-filled teeth are used as abutments for FPDs, fiber-post restorations or the creation of abutments from similar structures (ET/ET or FPR/FPR) results in improved conservation of root structure under loading when compared to the abutments from different structures (S/ET, ET/S, FPR/S, S/FPR).Article Which Is Effective on Bond Strength of Resin-Based Sealers: Incorporation of Powdered Dentin To Primer or Adhesive(Taylor & Francis Ltd, 2015) Akman, Melek; Belli, Sema; Ozcopur, Betul; Eskitascioglu, GuercanThe aim of this study was to investigate the effect of adding powdered dentin to primer or adhesive in a self-etch system on the shear bond strength of three resin-based sealers. Seventy-two premolars were sectioned buccolingually, and 144 root halves were divided into three groups according to the sealer used: epoxy resin-based sealer (AH Plus), methacrylate resin-based (RealSeal, Hybrid Root SEAL) n=48. The surfaces were irrigated with 5% NaOCl, 17% EDTA, distilled water for 5min. Four subgroups were created (n=12): control group; Clearfil Liner Bond 2V treated group; powdered dentin added to the primer of Clearfil Liner Bond 2V (40 wt.%); and powdered dentin added to the adhesive of Clearfil Liner Bond 2V (20 wt.%). Dentin powder was prepared. Three mm high buildups with a constant surface area of 3.45mm(2) were created using the sealers and allowed to set (37oC, 100% humid, 72h). The samples were tested to failure for shear bond strength (1mm/min). The data were calculated (MPa) and analyzed using two-way ANOVA, one-way ANOVA, and Tukey HSD tests. Adhesive use decreased the bonding performance of AH Plus (p=0.00). Mean bond strength of the other sealers was found similar to control. Primer or adhesive resin with powdered dentin did not increase the adhesive performance of the self-etch system used. The shear bond strength of RealSeal was significantly increased when powdered dentin was added to primer or adhesive (p=0.00). The effect of adding powdered-dentine to primer or adhesive in a self-etch system on the shear bond strength was sealer-dependent .