Browsing by Author "Akman, Melek"

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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, Greg
Background/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.
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, Sema
The 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).
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, Guercan
The 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 .