Yazar "Yilmaz, Berivan Dundar" seçeneğine göre listele

Listeleniyor 1 - 5 / 5
  • [ X ]
    Öğe
    The Comparison of Different Surface Preparation Methods in Terms of Shear Bond Strength of Tri-ceram Porcelain-titanium Alloy
    (Galenos Yayincilik, 2019) Yilmaz, Berivan Dundar; Mese, Ayse; Kaya, Eylem
    Objective: Several studies have been made to evaluate effects of the surface preparation on shear bond strength (SBS) of titanium-porcelain complex. However, a completed picture has not been obtained yet. Therefore, such studies appear frequently on recent literature. The purpose of this study is to determine a simple method providing strong SBS and using fewer parameters. Materials and Methods: Sixty titanium samples were equally divided into five groups. Group 1: Control (C). Group 2: Airborne-particle abrasion with 250 mu Al2O3 (250 mu AbPA). Group 3: Etching with 10% HCl (10% HCl). Group 4: Etching with Nd:YAG Laser at 6W (Nd6). Group 5: Etching with Nd:YAG laser at 7 W (Nd7). Results: Mean SBS value of C (10.69 MPa) was close to that of 250 mu AbPA (10.57 MPa). The mean value of 10% HCl (19.37 MPa) was nearly twice higher than C, whereas those of laser groups (8.89 MPa and 8.77 MPa) were smaller than C. There was no overlap between SBS values of samples etched with 10% HCl and those of other samples. Multiple comparisons indicated a significant difference between acid group and others (p=0.00). Laser groups were different from control, too. The failure mode of % HCl group was 67% adhesive and 33% mix, while those of other groups were cohesive or mix. Conclusion: Titanium surfaces etched with 10% HCl provides significantly strong SBS values. This method requires only the use of aqueous solution of 10% HCl, and boiling process for 30 minutes. Such a simplicity suggests that etching with 10% HCl provides a very simple surface preparation method which involves in use of fewer parameters.
  • [ X ]
    Öğe
    Comparison of the clinical efficacy of two different types of post systems which were restored with composite restorations
    (Baishideng Publishing Group Inc, 2018) Ayna, Buket; Ayna, Emrah; Celenk, Sema; Basaran, Emine Goncu; Yilmaz, Berivan Dundar; Tacir, Ibrahim Halil; Tuncer, Mehmet Cudi
    AIM To compare the efficacy of resin composite restorations, retained with either polyethylene or zirconia-rich glass fiber posts. METHODS Sixty-two single rooted maxillary and mandibular central incisor teeth in forty-four patients (15 males and 29 females; age range 15-32 years) were restored either with an ultrahigh molecular weight polyethylene (UHMWP) fiber post (Bondable Reinforcement Ribbon, DENSE, Ribbond, Seattle, WA, United States) or a zircon-rich glass fiber post (Snowpost, Lot H 040; Carbotech, Ganges, France). Then, direct resin composite restoration (Clearfil AP-X, Kuraray) was performed for both post systems in tooth color suitable. Patients were recalled for routine inspections at 6 mo, 1, 2 and 3 years. RESULTS The restorations were assessed during each recall evaluation according to predetermined clinical and radiographic criteria (periapical lesion; marginal leakage and integrity; color stability; surface stain and loss of retention of the post or the composite buildup material). The follow-up data showed no significant difference in these criteria between polyethylene fibre posts and zirconia-rich glass fibre posts. CONCLUSION The efficacy of resin composite restorations, retained with either polyethylene or zirconia-rich glass fiber posts were similar, suggesting that both types of fiber post can be used successfully to help retain resin composite restorations.
  • [ X ]
    Öğe
    Evaluation of Bond Strength of Different Repair Methods Applied in PEEK Infrastructure Restorations
    (Sci Printers & Publ Inc, 2021) Yilmaz, Berivan Dundar; Cetinkaya, Numan; Polat, Zelal Seyfioglu; Unal, Server Mutluay; Tuncer, Mehmet Cudi
    OBJECTIVE: To evaluate the appropriate intraoral repair procedures in PEEK (polyetheretherketone) restorations when there is a veneer fracture. STUDY DESIGN: The study groups were formed according to the presence or absence of fractured veneer material of PEEK restorations. PEEK specimens (N = 91) were prepared with CAD/CAM in dimensions of 5 x 5.4 x 13 mm and divided into 13 groups including the positive control group. 5000 thermocyclic was applied to the specimens, and then the repair bond strength (RBS) was made at a speed of 0.5 mm/min. The fracture surfaces of the specimens were examined under a stereomicroscope. SEM, EDX, XRD, AFM, and surface contact angle analyses were performed in terms of roughened surfaces of PEEK (N = 16). One-way ANOVA and independent sample t test were used for data analysis (alpha = 0.05). RESULTS: The efficiency of surface treatment, the roughness and wettability of the acid and Co-Jet groups have increased. Acid etching was found to be the most effective surface treatment. The RBS values of the Super-Bond groups in the repair procedures were found to be higher than the Visio.link group and were statistically significant (p = 0.002). When evaluating failure modes, the mode most encountered among all groups was the mixed mode, and least was the cohesive mode. CONCLUSION: The presence or absence of fractured veneer during the repair of PEEK-based restorations does not affect the values of repair bond strength, and RBS values were also not statistically significant.
  • [ X ]
    Öğe
    Interaction of Water and Fiber Free and Fiber Reinforced Acrylic Resins: Studied by 400 MHz NMR
    (Asian Journal Of Chemistry, 2011) Polat, Zelal Seyfioglu; Tacir, Ibrahim Halil; Yilmaz, Berivan Dundar; Korunur, Sibel
    There is no report is available on the interaction of polymerized acrylic resin materials with water studied by high resolution NMR. In this study, the chemical shifts of NMR peaks of water interacting with different types of polymerized acrylic resin materials were compared. Two different types of polymers obtained by heat and microwave, were selected. Each NMR sample was prepared by mixing the dusty materials and 1 mL of a mixture of H2O (80 To) and D2O (20 %). The water proton signals in samples were measured by 400 MHz NMR. The data was divided into four groups. The chemical shifts of microwave acrylic resin (group 3) was higher than that of microwave acrylic resin reinforced with glass fibers (group 4), while the chemical shift of heat cured acrylic resin (group 1) was higher than that of heat cured acrylic resin reinforced with glass fibers (group 2). Furthermore, the chemical shifts of material polymerized by microwave are higher than those polymerized by injection (group 3 > group 1, and group 4 > group 2). Data shows that different type of polymerized acrylic resin materials can be differentiated by chemical shift measurements.
  • [ X ]
    Öğe
    Laser Application to the Root Surface Increases the Bonding Strength of Surface-Treated Prefabricated Glass-Fiber Posts in Teeth with Excessive Substance Loss
    (Int Scientific Literature, Inc, 2018) Gorus, Zuhal; Mese, Ayse; Yilmaz, Berivan Dundar; Adiguzel, Ozkan
    Background: This study examined the effect of roughening of the root surface using an erbium-doped yttrium aluminum garnet (Er: YAG) laser on the binding strength of teeth undergoing root canal treatment. Material/Methods: Ninety single-rooted teeth were used and assigned randomly to 9 groups (n=10 each). Root canals were prepared using the FlexMaster rotary system. An Er: YAG laser was applied to the root canals in Group 1, with no surface treatment of the glass-fiber post. In Group 2, aluminum oxide particles were applied. In Group 3, the laser was applied to the root canals, with Cojet treatment. Group 4 received laser treatment and Clearfil Ceramic Primer. In Group 5, Clearfil Ceramic Primer silane coupling was performed on post surfaces without laser treatment. In Group 6, hydrofluoric acid (HF) application was followed by Clearfil Ceramic Primer cementing of the glass post surfaces with laser application. In Group 7, HF acid treatment was performed without laser. In Group 8, the laser was applied, followed by sanding of post surfaces using Korox 50, and silane coupling with Clearfil Ceramic Primer. In Group 9, the post surfaces were sanded using Korox 50 with laser application to the root canals. The samples were subjected to a push-out experiment. The data were analyzed using Friedman's test and the Wilcoxon signed-rank test. Results: A significant difference in bonding strength was found among the groups (p < 0.005). Conclusions: Use of an Er: YAG laser in the root canal may be beneficial prior to bonding of glass posts.