Yazar "Polat, Zelal Seyfioglu" seçeneğine göre listele

Listeleniyor 1 - 11 / 11
  • [ X ]
    Öğe
    Addition of benzalkonium chloride to self-adhesive resin-cements: some clinically relevant properties
    (Informa Healthcare, 2014) Ahmet, Serra Oguz; Mutluay, M. Murat; Polat, Zelal Seyfioglu; Dirihan, Roda Seseogullari; Bek, Bulent; Tezvergil-Mutluay, Arzu
    Objective. The clinical survival rates of the adhesive restorations are limited due to the deterioration of resin-dentin bonds over time, partly due to the endogenous enzymatic activity of dentin. Recently, benzalkonium chloride (BAC) has been shown to effectively inhibit endogenous protease activity of dentin. This study evaluated the effect of different concentrations of benzalkonium chloride (BAC) on the degree of conversion (DC), vickers hardness (VH), setting time (ST) and biaxial flexural strength (FS) of two self-adhesive resin luting cements (RC). Methods. Two RC SpeedCEM (Ivoclar-Vivadent) and BisCem (Bisco) were modified by addition of 0.1, 0.5, 1, 1.5, 2 wt% BAC. The luting cements without the addition of BAC served as control. The DC (FT-IR/ATR from the bottom of the resin disc), vickers hardness (from top and bottom of the light-cured specimen), setting time (ISO 4049) and biaxial flexural strength (0.6 x 6 mm discs) of the specimens were tested. Data were analyzed using ANOVA and Tukeys HSD. Results. DC results were in the range of 70-80%, with some significant changes in BisCem (p < 0.05). VH values of both materials increased significantly compared to control, with no significant change as the BAC percentage increases. BAC addition influenced the ST differently for both materials. For BisCem, a gradual decrease (p < 0.05) was observed whereas, for SpeedCEM, a gradual increase was observed until 1% BAC (p < 0.05). For FS values, a gradual decrease was observed for both materials with increased amounts of BAC (p < 0.05), compared to the control group. Conclusions. BAC addition of up to 1% seems to be acceptable considering the properties tested. Clinical significance. Incorporation of benzalkonium chloride to self-adhesive resin luting cements during the mixing procedure does not significantly affect the degree of conversion or flexural strength of the luting agent and may be a good option to improve the durability of adhesive interface.
  • [ X ]
    Öğe
    Effect of ultrashort pulsed laser on bond strength of Y-TZP zirconia ceramic to tooth surfaces
    (Japanese Soc Dental Materials Devices, 2015) Unal, Server Mutluay; Nigiz, Remzi; Polat, Zelal Seyfioglu; Usumez, Aslihan
    There is limited knowledge about the effects of ultrashort pulsed laser on zirconia ceramic surfaces. The aim of this study was to evaluate the effects of ytterbium (Yb)-doped fiber laser and other surface treatment methods -namely, sandblasting with 110 mu m aluminum oxide or 30 mu m silica-coated alumina on shear bond strength (SBS) of zirconia to tooth surface. A total of 128 zirconium oxide disks were made by using CAD-CAM technology. Disk surfaces were sandblasted with Al2O3 particles or silica-coated alumina or irradiated with Yb-doped fiber based nanosecond pulsed laser at 85W output power at 25 kHz. Disks were luted to dentin using two different resin cement. SBS of each specimen was measured. Results were statistically analyzed using two-way analysis of variance (ANOVA) and Bonferroni and Dunnett tests (p<0.005). Highest bond strength was obtained when zirconia surface was pretreated with Yb-doped fiber-based nanosecond pulsed laser regardless of the resin cement used.
  • [ X ]
    Öğe
    The Effect of Ytterbium-Doped Fiber Laser with Different Parameters on Physical Properties of Zirconia Surface
    (Mary Ann Liebert, Inc, 2017) Unal, Server Mutluay; Ozkir, Serhat Emre; Polat, Zelal Seyfioglu; Guven, Sedat; Asutay, Hilal
    Objective: Laser irradiation is an alternative surface treatment method for roughening zirconia surfaces. The aim of this study was to evaluate the effects of ytterbium-doped fiber laser (YbPL) on zirconia. Background: Zirconia surfaces are resistant to many surface treatment methods, but surface roughness is crucial for adhesion of veneering materials and cements to zirconia. Methods: The zirconia discs were prepared and divided into four groups according to the power of the laser irradiation (5, 12, 17, and 20W). These groups were divided into five subgroups according to the frequency (25, 40, 60, 80, and 100kHz). Surface roughness values were measured with a noncontact profilometer, and the mean Ra values were calculated. Wettability was measured with a goniometer. The surface morphology was observed with a scanning electron microscope (SEM). The changes in the surface crystalline structure were analyzed with X-ray diffractometry. Results: Ra values of all groups were higher than the control group. The highest surface roughness value was at 20W and 100kHz. Best wettability characteristic was observed at 5W and 60kHz. The correlations between Ra and wettability were low but significant. SEM examination of 5W with different frequencies showed no microcracks, however, melted areas were observed. Remaining groups had microcracks and melted layers. A significantly lower T/M-phase transformation was observed in some groups. Conclusions: YbPL irradiation was effective at roughening the zirconia surface. Although laser treatment affected zirconia surfaces and provided surface roughness, the power and frequency should be adjusted to achieve optimum results.
  • [ X ]
    Öğe
    Esthetic rehabilitation of avulsed-replanted anterior teeth: a case report
    (Wiley-Blackwell, 2008) Polat, Zelal Seyfioglu; Tacir, Ibrahim Halil
    Avulsion is a complex injury affecting the pulp, periodontal ligament and the alveolar bone. Avulsed permanent teeth can survive following replantation. However, post-traumatic external root resorption eventually resulting in loss of the traumatized tooth is a frequent finding. After replantation of the avulsed teeth, esthetic requirements can be needed. Treatment options include porcelain laminate veneers, metal-ceramic restorations and all-ceramic crowns as well as minimally invasive procedures such as direct resin composite bonding. This article describes the restoration of avulsed and replanted teeth with direct resin composite laminate veneers. Because of the fact that lost fragments were recovered with the loss of anterior esthetic, and bearing in mind the patient's psychologically affected, we considered direct resin composite laminate veneer restoration of the avulsed and replanted teeth as the best therapeutic option. The patient was satisfied with the final result.
  • [ 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
    Evaluation of Temperature and Stress Distribution on 2 Different Post Systems Using 3-Dimensional Finite Element Analysis
    (Int Scientific Literature, Inc, 2015) Deger, Yalcin; Adiguzel, Ozkan; Ozer, Senem Yigit; Kaya, Sadullah; Polat, Zelal Seyfioglu; Bozyel, Bejna
    Background: The mouth is exposed to thermal irritation from hot and cold food and drinks. Thermal changes in the oral cavity produce expansions and contractions in tooth structures and restorative materials. The aim of this study was to investigate the effect of temperature and stress distribution on 2 different post systems using the 3-dimensional (3D) finite element method. Material/Methods: The 3D finite element model shows a labio-lingual cross-sectional view of the endodontically treated upper right central incisor and supporting periodontal ligament with bone structures. Stainless steel and glass fiber post systems with different physical and thermal properties were modelled in the tooth restored with composite core and ceramic crown. We placed 100 N static vertical occlusal loading onto the center of the incisal surface of the tooth. Thermal loads of 0 degrees C and 65 degrees C were applied on the model for 5 s. Temperature and thermal stresses were determined on the labio-lingual section of the model at 6 different points. Results: The distribution of stress, including thermal stress values, was calculated using 3D finite element analysis. The stainless steel post system produced more temperature and thermal stresses on the restorative materials, tooth structures, and posts than did the glass fiber reinforced composite posts. Conclusions: Thermal changes generated stresses in the restorative materials, tooth, and supporting structures.
  • [ X ]
    Öğe
    Influence of different cavity preparation designs on fracture resistance of onlay and overlay restorations using different CAD/CAM materials
    (Mosher & Linder, Inc, 2017) Salman, Gizem On; Tacir, Ibrahim Halil; Polat, Zelal Seyfioglu; Salman, Afsin
    Purpose: To evaluate fracture strength of different preparation designed onlay and overlay restorations produced by Computer Aided Design/Computer Aided Manufacturing (CAD/CAM) and three different new ceramic polymer blocks. Methods: Ninety-one extracted human mandibular molars were used in this study. Preparations were made as (1) Only functional cusps reduction, (2) Only functional cusps reduction+rounded shoulder finish line, (3) All cusps reduction, or (4) All cusps reduction+rounded shoulder fmish line. Then these four cavity types were restored with three different materials: VITA Enamic, GC Cerasmart, Lava Ultimate. Thirteen groups were created by added control group (n= 7). Adhesive cementation was achieved by using a dual cured composite resin adhesive cement RelyX Ultimate. All samples were subjected to thermocycling for 5,000 cycles in water baths between 50 degrees C and 55 degrees C. The fracture resistance of specimens was determined under compressive loads along the long axis of the restored teeth at 0.5 mm/minute crosshead speed until fracture with a universal test machine. Fracture types of restored groups were evaluated. For fracture resistance data, one-way ANOVA; for correlation between material type and preparation design, two-way ANOVA were used. Percentage table and Kruskal-Wallis test were performed for analysis of fracture types. Results: There was no significant difference between all the groups (one-way ANOVA, P> 0.05). Group 4 showed statistically higher fracture strength values than Group 1 and no significant difference was found among other preparation designs by two-way ANOVA that compared all types of preparation designs regardless of material difference (P< 0.05).
  • [ 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
    Restoration of an intruded maxillary central incisor with a uniquely designed dowel and core restoration: A case report
    (Blackwell Publishing, 2007) Polat, Zelal Seyfioglu; Tacir, Ibrahim Halil
    This article describes the restoration of an intruded root using a custom-made metal dowel and metal-ceramic veneer core restoration. The treatment plan for this patient consisted of restoring the missing esthetics and eliminating psychological trauma by utilizing the root of the intruded maxillary left central incisor to replace both missing central incisor crowns. This treatment will preserve space and bone until the patient is old enough for another prosthodontic restoration to be considered.
  • [ X ]
    Öğe
    Restoring of traumatized anterior teeth: a case report
    (Wiley, 2008) Polat, Zelal Seyfioglu; Tacir, Ibrahim Halil
    The fracture of anterior teeth in children creates psychological impact on both the parents and the child especially if the injury affects the permanent dentition and involves the loss of extensive tooth structure. Besides the pain and discomfort from the injury, the child's changed appearance may make him the target for teasing and even ridicule by other children. Traumatic teeth can be treated in different ways, in the WHO system, eight groups were classified according to the anatomical structure involved, and treatment planning depends on the type of the injuries to the teeth and their supporting structures. This article describes the restoration of smile of the patients after fractured of teeth by different treatment options available. Because of the fact that lost fragmans were not recovered, and bearing in mind the patient age, we considered composite-veneered amalgam restoration of the fractured teeth as the best therapeutic option. The patient was satisfied with the final result.
  • [ X ]
    Öğe
    Retentive force of three fiber-reinforced resin composite posts and a zirconia post cemented with two adhesive luting agents
    (Japanese Soc Dental Materials Devices, 2007) Polat, Zelal Seyfioglu; Tacir, Ibrahim Halil; Eskimez, Sebnem; Celik, M. Yusuf
    By means of a pull-out test, this study compared the retentive force of three fiber-reinforced resin composite posts and a zirconia post. These posts were cemented using two different dual-polymerizing adhesive resin luting agents. Forty freshly extracted canines were selected for the study. All tooth root were endodontically treated and the post spaces prepared. The posts were luted using luting agents according to the manufacturers' guidelines. A tensile force was applied, and all data were collected and analyzed statistically. Glass fiber posts that were luted with Panavia F (Group 3) had the highest median load (3.610 N), while zirconia posts that were luted with RelyX ARC (Group 8) had the lowest median load (0.926 N). Among the different post systems that were luted with Rely X ARC, significant differences were observed in their median tensile loads (p<0.047). When comparing between Panavia F and RelyX ARC of each post system, a significantly higher tensile load was seen with zirconia posts luted with Panavia F (Group 7) (p<0.032).