Yazar "Aykent, Filiz" seçeneğine göre listele
Listeleniyor 1 - 20 / 30
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe A 1- to 12-year clinical evaluation of 106 endosseous implants supporting fixed and removable prostheses(QUINTESSENCE PUBLISHING CO INC, 2007) Aykent, Filiz; İnan, Özgür; Özyeşil, Atilla Gökhan; Alptekin, Nilgün ÖzlemThe purpose of this article is to report on the long-term clinical evaluation of patients treated with dental implants. A total of 106 implants were placed in 34 patients and restored with fixed partial dentures and overdentures. The 12-year cumulative implant survival and success rates were 95.2% and 90.2%, respective Probing depths around mandibular implants were significantly lower than those around maxillary implants (P <.05). The cumulative implant success rate in nonsmokers was 97.7%, but this dropped to 75.81 % in smokers. Also, patients rehabilitated with implant-supported overdentures had more peri-implant tissue inflammation than patients with fixed prostheses.Öğe Bilgisayar Desteği ile Hazırlanan Dental Seramikler (CAD/CAM)(2008) Yöndem, İsa; Aykent, FilizEstetik ve biyouyumlu olmalarından dolayı tam seramik restorasyonların tercihinde önemli bir artış meydana gelmiştir. Seramik materyalinin ilerleyen teknoloji ile fiziksel ve mekaniksel özelliklerinin geliştirilmesi kullanım alanını da genişletmektedir. Diş hekimliğinde CAD/CAM teknolojisi her geçen gün gelişmeye devam etmektedir ve geleneksel kayıpmum- döküm tekniğine bir alternatif olarak önem kazanmaktadır. Devamlı gelişmeleri göz önünde bulundurularak, CAD/CAM teknolojisi gelecekte de dental restorasyonları üretmekte önemli bir teknoloji olduğunu göstermektedir. Bu teknoloji ile üstün kalite ve hatasız restorasyonlar yapmak mümkündür aynı zamanda kullanılan diğer tekniklere göre daha az laboratuar çalışma ve daha az maliyet gerektirir.Öğe Bond Strength of Porcelain to Acid or Er,cr : Ysgg Laser Etched Enamel(Int Amer Assoc Dental Researchi a D R/a a D R, 2003) Üşümez, A.; Aykent, Filiz[Abstract not Available]Öğe Bond Strengths of Porcelain Laminate Veneers to Tooth Surfaces Prepared With Acid and Er,cr : Ysgg Laser Etching(Mosby-Elsevier, 2003) Üşümez, Aslıhan; Aykent, FilizStatement of problem. The erbium, chromium: yttrium, scandium, gallium, garnet (Er,Cr:YSGG) hydrokinetic laser system has been successful in the ablation of dental tissues. It has been reported that this system is also useful for preparing tooth surfaces for adhesion, but results to date have been controversial. Purpose. This in vitro study evaluated the bond strengths of porcelain laminate veneers to tooth surfaces after etching with acid and Er,Cr:YSGG laser conditioning. Material and method. Forty extracted caries- and restoration-free human maxillary central incisors were used. The teeth were sectioned 2 mm below the cementoenamel junction. The crowns were embedded in autopolymerizing acrylic resin with the labial surfaces facing up. The labial surfaces were prepared with .05 mm reduction to receive porcelain veneers. The teeth were divided into 4 groups of 10 specimens. Thirty specimens received 1 of the following Surface treatments before the bonding of IPS Empress 2 laminate veneers: (1) laser radiation from an Er,Cr:YSGG laser unit; (2) 37% orthophosphoric acid; and (3) 10% maleic acid. Ten specimens received no surface treatment and served as the control group. The veneers were bonded with dual-polymerizing resin, Variolink II. One microtensile specimen from each of the cervical and incisal thirds measuring 1.2 x 1.2 mm was prepared with a slow-speed diamond saw sectioning machine with a diamond-rim blade. These specimens were attached to opposing arms of the microtensile testing device with cyanoacrylate adhesive and fractured under tension at a crosshead speed of 1 mm/min, and the maximum load at fracture (Kg) was recorded. The data were analyzed with a 2-way analysis of variance and Tukey HSD tests (alpha=.05). Results. No statistically significant differences were found among the bond strengths of veneers bonded to tooth surfaces etched wish Er,Cr:YSGG laser (12.1 +/- 4.4 MPa), 37% orthophosphoric acid (13 +/- 6.5 MPa), and 10% maleic acid (10.6 +/- 5.6 MPa). The control group demonstrated the lowest bond strength values in all test groups. Statistically significant differences were found between the bond strengths of cervical and incisal sections (P<.001). Conclusion. In vitro microtensile bond strengths of porcelain laminate veneers bonded to tooth surfaces that were laser-etched showed results similar to orthophosphoric acid or maleic acid etched tooth surfaces.Öğe Color Stability of CAD/CAM Fabricated Inlays after Accelerated Artificial Aging(WILEY, 2016) Karaokutan, Isil; Yilmaz Savas, Tuba; Aykent, Filiz; Ozdere, EdaPurposeTo investigate the influence of accelerated artificial aging on the color stability of three different inlay restorations produced with a CAD/CAM system. Materials and MethodsThirty non-carious human mandibular molar teeth were used. The teeth were embedded in autopolymerizing acrylic resin blocks. Standard Class I inlay cavities were prepared, and the teeth were randomly divided into three groups (n = 10) to fabricate inlay restorations: (1) a feldspathic-ceramic group, (2) a resin nano-ceramic group, and (3) a leucite glass-ceramic group. Optical impressions were made with CEREC software, and the restorations were designed and then milled. The inlays were adhesively cemented with a dual-polymerizing resin cement and left in distilled water at room temperature for 1 week. Color measurements were performed with a spectrophotometer before and after accelerated aging in a weathering machine with a total energy of 150 kJ/m(2). Changes in color (E, L, a, b, C) were determined using the CIE L*a*b* system. The results were assessed using a one-way ANOVA and Tukey's HSD test (p = 0.05). ResultsThe color changes of the materials ranged from 2.1 to 9.29. The highest color change was seen in the resin nano-ceramic material. This change was not clinically acceptable (E > 5.5). No significant differences were found in the L and a values of the test groups. ConclusionsColor changes were observed in each evaluated material after accelerated aging. All CAD/CAM inlays became darker in appearance, more saturated, a little reddish, and more yellow.Öğe Complex Midfacial Reconstruction With an Implant-Supported Framework(LIPPINCOTT WILLIAMS & WILKINS, 2011) Akman, Serhan; Kalayci, Abdullah; Ataoglu, Hanife; Aykent, FilizThis clinical report describes the treatment of a patient with osseointegrated extraoral implants supporting a framework retainer and acrylic resin mesostructures and a large silicone mid-facial prosthesis. A metal framework was used to splint the implants together and provided satisfactory retention for the facial prosthesis. A 2-piece prosthesis that composed of an obturator and facial prosthesis was fabricated. Cosmetic improvements as well as the ability to speak, swallow, and, to a lesser degree, chew, were achieved for this patient.Öğe Dentin Bond Strengths of Two Ceramic Inlay Systems After Cementation With Three Different Techniques and One Bonding System(MOSBY-ELSEVIER, 2003) Özturk, Nilgün; Aykent, FilizStatement of problem. Cementation of inlay restoration is critical. Because of its high organic content, dentin is a less favorable substrate for bonding than enamel. Therefore it is important to improve dentin adhesion when placing ceramic inlay restorations. Purpose. The purpose of this study was to compare the dentin bond strengths of 2 different ceramic inlay systems after cementation with 3 different techniques and I bonding system. Material and methods. One hundred twenty freshly extracted caries- and restoration-free molar teeth used in this study were stored in saline solution at room temperature. Standardized Class I preparations were made in all teeth. Each preparation had a length of 6 mm, a width of 3 mm, a depth of 2 mm, and 6-degree convergence of the walls. Teeth were randomly assigned to 2 groups of 60 each to evaluate the bonding of 2 ceramic systems, Ceramco 11 (Group I) and IPS Empress 2 (Group II), to dentin. Each of the 2 groups were further divided into 3 cementation technique groups of 20 each (Group I A, B, and C and Group II A, B, and Q. Groups I A and B and Groups II A and B used dentin bonding agent (DBA) Clearfil Liner Bond 2V, and resin cement (Panavia F). Groups I C and II C served as control groups and used Panavia F without the dentin-bonding agent. In Groups I A and II A, the DBA was applied immediately after the completion of the preparations (D-DBA). Impressions were then made, and the ceramic inlays were fabricated according to the manufacturers' guidelines. In Groups I B and II B the DBA was applied just before luting the inlay restorations (I-DBA). In Groups I C and II C, no bonding agent was used before the cementation of the inlay restorations (No DBA). Cementation procedures followed a standard protocol. After cementation, specimens were stored in distilled water at 37degrees C for 24 hours. The teeth were sectioned both mesial-distally and buccal-lingually along their long axis into three 1.2 X 1.2 mm wide I-shaped sections. The specimens were then subjected to microtensile testing at a crosshead speed of 1 mm/min, and the maximum load at fracture (in kilograms) was recorded. Two-way analysis of variance and Tukey honestly significant difference tests were used to evaluate the results (P<.05). Scanning electron microscopy analysis was used to examine the details of the bonding interface. The fractured surfaces were observed with a stereomicroscope at original magnification x22 to identify, the mode of fracture. Results. Although no significant difference was found among the 2 ceramic systems with regard to dentin bond strengths (P>.05), the difference between the cementation techniques was found to be significant (P<.001). Comparison among techniques showed that the dentin bond strength in the D-DBA technique had a significantly higher mean (40.27 +/- 8.55 Kg) than the I-DBA (30.20 +/- 6.78 Kg) and No DBA techniques (32.43 +/- 8.58 Kg). As a result of scanning electron microscopy analysis, a distinct and thicker hybrid zone with more, and longer resin tags were found in specimens treated with the D-DBA technique than with the other 2 techniques. Most failures (353 of 360) were adhesive in nature at the bonding resin/dentin interface. Only 7 specimens showed cohesive failure within the bonding resin. Conclusion. Within the limitations of this in vitro study, the cementation of the ceramic inlays tested with the D-DBA technique used resulted in higher bond strengths to dentin.Öğe Effect of Dentin Bonding and Ferrule Preparation on the Fracture Strength of Crowned Teeth Restored With Dowels and Amalgam Cores(Mosby-Elsevier, 2006) Aykent, Filiz; Kalkan, Mustafa; Yücel, Münir Tolga; Özyeşil, Atilla GökhanStatement of problem. It is necessary to obtain an adequate bond at the core/dentin junction where the majority of failures occur. The effect of recently developed dentin bonding agents on the fracture resistance of endodontically treated teeth at the amalgam core/dentin junction is unclear. Purpose. The Purpose of this study, was to evaluate the effects of 2 dentin bonding agents and a ferrule preparation on the fracture resistance of crowned mandibular premolars incorporating prefabricated dowel and silver amalgam cores. Material and methods. Sixty extracted mandibular second premolars were divided into 6 groups of 10 each. The coronal portion of each tooth was removed at the cemento-enamel junction (CEJ) in the first 3 groups. In the other groups, teeth were sectioned 1 nun above the CEJ to create a ferrule. After root canal preparations, prefabricated dowels (ParaPost) were placed. The first group served as a control and was tested without application of bonding agents and without incorporation of a ferrule design. In the second and third groups, respectively, an autopolymerizing adhesive (Superbond D-Liner) and a dual-polymerizing adhesive (Panavia F) were applied to tooth surfaces before restorative procedures. For the fourth (ferrule) group, no bonding agent was applied, but a 1-mm ferrule preparation was used. In the fifth (ferrule+D-Liner) and sixth (ferrule+Panavia F) groups, respectively, autopolymerizing and dual-polymerizing bonding agents were used in conjunction with the ferrule preparation. After amalgam core fabrication, Ni-Cr full cast crowns for each group were prepared and cemented. All specimens were stored in water for I week and thermal cycled 1000 times between 5 degrees and 55 degrees C. A compressive shear load was applied at an angle of 135 degrees to the crown, and the maximum load at fracture (N) was recorded. The data were analyzed with 1-way ANOVA and Tukey Honestly Significant Difference tests (alpha=.05). Results. Significantly higher fracture strength values were demonstrated for the ferrule+Panavia F (652.5 N), ferrule+D-liner (649.1 N) and ferrule (592.4 N) groups, respectively, than for the other groups. The next highest fracture strength values were found for the D-Liner (485.0 N) and Panavia F (486.3 N) groups. The control group (376.6 N) demonstrated the lowest fracture strength in all test groups (P<.001). Conclusion. A ferrule preparation or a bonding agent designed for silver amalgam core-dentin bonding can each increase the fracture strength for teeth receiving cast crowns after endodontic therapy and dowel and amalgam core restorations.Öğe Effect of Different Finishing Techniques for Restorative Materials on Surface Roughness and Bacterial Adhesion(MOSBY-ELSEVIER, 2010) Aykent, Filiz; Yöndem, İsa; Özyeşil, Atilla G.; Günal, Şölen K.; Avunduk, Mustafa C.; Özkan, SemihaStatement of problem. The formation of biofilm and bacterial accumulation on dental materials may lead to the development of gingival inflammation and secondary caries. Purpose. The purpose of this study was to examine the effect of different surface finishing and polishing methods on surface roughness and the adhesion of S. mutans bacteria to 2 new-generation indirect composite resins, 1 direct composite resin, and 1 ceramic material. Material and methods. Forty specimens (10 x 10 x 2 mm) of each material, indirect composite resins (SR Adoro, Estenia), direct composite resin (Tetric), and a ceramic material (VITABLOCS Mark II), were fabricated. Specimens were divided into 4 groups (n=10) that were treated with 1 of the following 4 surface finishing techniques: diamond rotary cutting instrument, sandpaper discs (Sof-Lex), silicone-carbide rubber points (Shofu), or a felt wheel with diamond paste. Surface roughness was measured with a profilometer. Test specimens were covered with artificial saliva and mucin to produce pellicle. Bacterial suspension (10(9) CFU/ml) was then added to the pellicle-coated specimens, and bacterial adhesion was determined using a confocal laser microscope and image analyzing program. Data were analyzed with 2-way ANOVA, followed by Tukey HSD test, Pearson correlation, and regression analysis (alpha=.05). Results. The highest surface roughness values were recorded in SR Adoro and diamond rotary cutting instrument groups. The lowest vital S. mutans adhesion was seen in the ceramic group and in SR Adoro indirect composite resin (P<.05). Conclusions. Bacterial adhesion to indirect composite resin materials differed from that to ceramic material after surface treatments. A positive correlation was observed between surface roughness and the vital S. rnutans adhesion.Öğe The effect of different surface treatments on roughnessand bond strength in low fusing ceramics(SPRINGER LONDON LTD, 2011) Kara, Haluk Baris; Ozturk, A. Nilgun; Aykent, Filiz; Koc, Ozlem; Ozturk, BoraThe aim of this study was to evaluate the influence of different surface treatments (air abrasion, acid etching, and laser irradiation) on the surface roughness and bond strength of a low fusing ceramic. Thirty-six discs of low fusing ceramic (Finesse, Ceramco) were prepared (10 mm in diameter and 2 mm in thickness) according to the manufacturer's instructions. Specimens were divided into three groups (n = 12), and the following treatments were performed: Air abrasion with alumina particles (50 mu m), acid etching with 5% HF and Nd:YAG laser irradiation (distance: 1 mm, 100 mJ, 20 Hz, 2 W, and 141.54 J/cm(2)). Following determination of surface roughness (R-a) by profilometry, specimens were examined with scanning electron microscopy (SEM). The luting cement (Clearfil Esthetic Cement) was bonded to the ceramic specimens using Teflon tubes. After 24 h of water storage, shear bond strength test was performed using a universal testing machine at a crosshead speed of 1 mm/min. The data were analyzed with two-way analysis of variance (ANOVA) and Tukey HSD tests (alpha = .05). Two-way ANOVA indicated that surface roughness was significantly affected by surface treatments (p < .001). Tukey honestly significant difference (HSD) indicated that the air abrasion group had a significantly higher mean value (p < .05) than the other groups. Shear bond strength was significantly affected by surface treatments (p < .001). Tukey HSD indicated that the air abrasion group had a significantly higher mean value (p < .05) than the other groups. No significant difference was found between the acid-etching and laser-irradiation groups (p > .05). The SEM image of the laser irradiation surface appeared to be relatively smooth as compared to the images of other the groups. Air abrasion of low-fusing porcelain surfaces was effective in improving the bond strength as compared to the acid-etching and laser-irradiation methods.Öğe Effect of Mouthrinses on Color Stability of Provisional Restorative Materials(2008) Sevimay, Müjde; Aykent, Filiz; Öztürk, Nilgün; Çökük, Neslihan; Yücel, M. TolgaAmaç: Bu çalışmanın amacı 24 saat farklı ağız gargaralarında bekletilmiş 4 farklı geçici restoratif materyalin renk stabilitilerini değerlendirmektir. Gereçler ve Yöntemler: 4 geçici restoratif materyalden 60 adet silindir şeklinde örnek; vinil etil metakrilat (Trim), metil metakrilat (Temdent), Etil metakrilat (Dentalon) ve bis-akril kompozit (Protemp II) üretici firma talimatlarına göre hazırlandı. Örnekler 4 gruba ayrıldı (n 15) ve distile su, Oral B, Listerine ve Klorheks içerisine bırakıldı. Renk ölçümleri kolorometre kullanılırak solüsyonlara daldırmadan önce ve daldırdıktan 24 saat sonra yapıldı. İstatistiksel analiz 2- yönlü varyans analizi (ANOVA) ölçümleri ve Tukey çoklu karşılaştırma testi kullanılarak gerçekleştirilmiştir (p.05). Bulgular: Geçici restoratif materyaller ve ağız gargaraları arasındaki etkileşim istatistiksel olarak farklı bulunmuştur (p.05). Trim (0.96), Dentalon (0.96) ve Protemp II (0.91) kabul edilebilir bir renk stabilitesi göstermişlerdir ve Temdent (1.5) ile karşılaştırıldıklarında en stabil renge sahip geçici restoratif materyallerdir. Listerine ağız gargarası Oral B ve Klorheksidin’den daha fazla boyama kapasitesi göstermiştir. Sonuç: Geçici restoratif materyaller ve ağız gargaralarının kombinasyonu renk stabilitesini etkileyen önemli faktörlerdir.Öğe Effect of Nd:YAG Laser Bleaching and Antioxidizing Agents on the Shear Bond Strength of Brackets(MARY ANN LIEBERT, INC, 2013) Akin, Mehmet; Ozyilmaz, Ozgun Yusuf; Yavuz, Tevfik; Aykent, Filiz; Basciftci, Faruk AyhanObjective:The aims of this study were to evaluate the effect of hydrogen peroxide bleaching agents, both nonactivated and activated by a neodymium:yttrium-aluminum-garnet (Nd:YAG) laser, and of antioxidant treatment on the shear bond strength (SBS) of orthodontic brackets. Background data:Nd:YAG laser activation is expected to accelerate the bleaching therapy without decrease shear bond strength. Materials and methods: Ninety extracted maxillary central incisors were divided into two experimental groups and a control group. Group I was the control group, Group II was bleached with 35% hydrogen peroxide and had no photoactivation, and Group III was bleached with 35% hydrogen peroxide with activation by a Nd:YAG laser (4.0 W, 60 Hz frequency, 1mm distance, 20 sec). Each group was divided into two subgroups:Subgroup A was immersed in artificial saliva for 2 weeks, and then bonded using the total etch system, whereas subgroup B was treated with an antioxidant agent (10% sodium ascorbate) and then bonded using the same system. The samples were stored in water for 24 h at 37 degrees C, and thermocycled. The SBS in megapascals (MPa) was determined by a shear test with 1mm/min crosshead speed, and failure types were classified with modified adhesive remnant index scores. The data were analyzed with two way analyses of variance, Tukey, and chi(2) tests at the alpha = 0.05 level. Results:In both Groups II and III, the SBSs of brackets bonded after bleaching (Group II 15.16, Group III 17.50 MPa) were significantly lower than those of brackets in the bonded unbleached group (Group I 22.13MPa); however, sodium ascorbate treatment significantly increased the SBSs of brackets in the bleached groups (Group II 21.52, Group III 22.43MPa), but had an insignificant effect on the SBS of the control group (Group I 23.66MPa). Conclusions: Hydrogen peroxide bleaching agents reduce the SBSs both with and without Nd:YAG laser activation; however, treatment of the bleached enamel surface with 10% sodium ascorbate prior to bonding negates the effect.Öğe Effect of surface treatment methods on the shear bond strength between resin cement and all-ceramic core materials(ELSEVIER, 2012) Yucel, Munir Tolga; Aykent, Filiz; Akman, Serhan; Yondem, IsaThis study compared the influence of various surface treatments on the shear bond strength between resin cement and lithium disilicate glass-ceramics. A series of 120 lithium disilicate ceramic samples were prepared to compare the effect of different surface treatments on the shear strength of a luting cement bonded to two all-ceramic systems. IPS Empress 2 and IPS e.max Press ceramic samples were fabricated according to the manufacturer's instructions. The ceramic samples were divided into the following 6 surface treatment groups for each ceramic system: 1-no treatment (C), 2-airborne-particle abrasion (A), 3-acid etching (E), 4-airborne-particle abrasion + acid etching (AE), 5-Nd:YAG laser (L), 6-Nd:YAG laser + acid etching (LE). Resin cement was then bonded to the treated ceramic surfaces and light polymerized. The shear bond strengths of the specimens were measured using a universal testing machine. Two-way ANOVA and Tukey HSD (alpha=0.05) test were used to determine differences in shear bond strength between the groups. The ANOVA revealed significant differences between the treatment groups and ceramic types (p < 0.05). The shear bond strengths of IPS Empress 2 were significantly higher than those of IPS e.max Press. (C) 2012 Elsevier B.V. All rights reserved.Öğe Effect of two light activated in-office bleaching agents on microhardness of different esthetic restorative materials*(Selçuk Üniversitesi, 2018) Ozyilmaz, Ozgun Yusuf; Alptekin, Tuncay; Aykent, Filiz; Kara, Haluk BarisBackground: Irradiation sources have been used to reduce the total in-office bleaching time. However, little is known about the effects of the light irradiation bleaching systems on the restorative materials. This in vitro study evaluated the microhardness of 6 different restorative materials during office bleaching procedures with blue light emitted diode and diode laser photoactivation. Methods: FiltekTM supreme (nanofilled), Tetric EvoCeram (nanohybrid), Tescera ATL (ormocer), Clearfill Majesty Esthetic (nanofilled), Durafill VS (microfilled) and IPS Empress II (ceramic) restorative materials were selected in this study. Twenty specimens, 10 mm in diameter and 2 mm thick, were fabricated from each material using a Teflon mold. All specimens were randomly assigned to two groups (n=10). Group 1 received two topical applications of 35% hydrogen peroxide and was photoactivated using blue light emitted diode for 20s. Group 2 received topical application of 46% hydrogen peroxide using diode laser for 30s. Baseline and after bleaching microhardness measurements were taken with a Vickers hardness tester that was used with a 300 g for the porcelain and 100 g for the composite and ormocer specimens, the dwell time was 30 s for all groups. Data were analyzed statistically, with one-way-analysis of variance (ANOVA), post-hoc Tamhane's T2 and independent t tests. Results: After application of both office bleaching agents, microhardness of all restorative materials tested were significantly decreased (p<.05). However, Tetric EvoCeram composite resin material showed the least microhardness value (p<.05). Conclusion: Blue light emitted diode and diode laser activation hydrogen peroxide office bleaching agents have similar effects on the reduction of microhardness of restorative materials. The data of this study revealed that after bleaching, nanofilled (FS, CME), microfilled (Df) specimens demonstrated lower changes in microhardness values than nanohybrid (TEC) composite material.Öğe Effect of Veneering Techniques on Shear and Microtensile Bond Strengths of Zirconia-Based All-Ceramic Systems(QUINTESSENCE PUBLISHING CO INC, 2017) Yilmaz Savas, Tuba; Aykent, FilizPurpose: To evaluate shear (SBS) and microtensile (mu TBS) bond strengths of zirconia cores veneered using different fabrication techniques. Materials and Methods: Seventy-five IPS e.max ZirCAD plates were fabricated and divided into three groups according to the following veneering techniques: layering, pressing, and CAD-on. The specimens of the layering group were veneered with IPS e.max Ceram, and the specimens of the pressing group were veneered with IPS e. max Zir-Press. Veneering ceramics in the CAD-on group were milled from IPS e.max CAD, fused with the core by using a glass-fusion ceramic, and then crystallized. Bond strength tests were performed using a universal testing machine at a crosshead speed of 0.5 mm/min for the SBS test and 1 mm/min for the mu TBS test. Mean SBS and mu TBS (MPa) were analyzed with one-way ANOVA and Tukey's HSD test (p < 0.05). Results: Significant differences in SBS were observed between the groups (p < 0.05). The mean SBS for the CAD-on group was significantly higher (31.89 +/- 5.83 MPa) than those of the layering (14.27 +/- 4.45 MPa) and pressing (12.23 +/- 3.04 MPa) groups. However, the mean mu TBS of the CAD-on (30.41 +/- 8.64 MPa), layering (21.71 +/- 3.40 MPa) and pressing (20.74 +/- 6.36 MPa) groups were not statistically significant (p > 0.05). Conclusion: The CAD-on technique showed the highest shear bond strengths of the tested groups, and most of the specimens failed cohesively instead of failing at the adhesive interface.Öğe Effects of fibers on the color change and stability of resin composites after accelerated aging(JAPANESE SOC DENTAL MATERIALS DEVICES, 2012) Tuncdemir, Ali Riza; Aykent, FilizComposite resins were reinforced with glass and polyethylene fibers in this study, and the effect of fiber reinforcement on the color change of composite resins was investigated. After accelerated aging, the effect of fiber reinforcement on the color stability of composite resins was also examined. There were three experimental groups (n=12 disks per group): non-fiber-reinforced composite (non-FRC control), polyethylene fiber (Ribbond-THM)-reinforced composite, and glass fiber (everstick NET)-reinforced composite. According to the critical remarks of color change of National Bureau of Standarts (NSB), glass fiber-reinforced anterior composites showed trace color change and polyethylene-fiber reinforced composites showed slight color change before accelerated aging. After accelerated aging, both control and fiber-reinforced composite groups showed noticeable color change. It was concluded that both the types of fiber reinforcement and composite resin influenced the color change of fiber-reinforced composite resins.Öğe Effects of Laser Irradiation and Sandblasting on Surface Characteristics of Polymethyl Methacrylate(Int Amer Assoc Dental Researchi A D R/A A D R , 2003) Üşümez, A.; İnan, Onur; Aykent, Filiz; Üşümez, S.[Abstract not Available]Öğe Evaluation of the Effect of Fracture Line Type on Repair Resistance in Acrylic Resins Repaired with Graphene Oxide(Selçuk Üniversitesi, 2022) Basmacı, Fulya; Ünsal, Gökçe Soğancı; Aykent, FilizBackground: The aim of this study is to investigate the effect of different fracture line designs and gaps on the fracture strength of graphene oxide repaired polymethylmethacrylate (PMMA) resin specimens. Methods: Fifty standard wax specimens with the size of 65x10x3 mm were prepared using a metal mold. The prepared wax models were randomly divided into 5 groups (n=10); group 1: control group (no fracture line was created), group 2: fracture line with 0 mm gap and flat surface, group 3: 0 mm gap and 45° bevel fracture line, group 4: Fracture line with 2.5 mm gap and flat surface, group 5: 2.5 mm gap and 45° bevel fracture line. The fracture lines of the specimens were repaired by adding 2% graphene oxide to PMMA powder. A 3-point bending test was applied to the midpoint of the fracture line of specimens in all test groups with an universal testing machine with a cross head speed of 0.5 mm/min. Results were analyzed by ANOVA and Tukey HSD test for normally distributed flexural strength data. The resilience data that did not show normal distribution were evaluated with the Kruskal-Wallis H test. The pvalue of <0.05 was considered statistically significant. Results: The highest flexural strength value was obtained in the control group (123.92±13.99 MPa). The lowest value was recorded in group 4 (39.01±8.23 MPa). The flexural strength of the speciments with bevel fracture lines was found to be statistically significantly higher than the flexural strength of specimens with straight fracture lines, (p<0.05). After repairing a decrease was monitored in the resilience of the speciments, but it was not found statistically significant (p=0.083). Conclusion: The bevel fracture line of acrylic resin specimens repaired with graphene oxide provided a significant advantage in increasing the flexural strength compared to the straight fracture line.Öğe Evaluation of the fracture strength of different CAD/CAM inlay restorations after accelerated aging(Selçuk Üniversitesi, 2019) Karaokutan, Işıl; Subaşı, Meryem Gülce; Aykent, FilizBackground: The purpose of this study was to compare the fracture resistance of inlay restorations manufactured by computer aided design/computer aided manufacturing (CAD/CAM) using different materials after accelerated artificial aging. Materials and Methods: Class I inlay preparations were made for 40 mandibular molar teeth. The teeth were allocated into four groups (n=10) according to the type of manufacturing material used: feldspathic-ceramic (CEREC blocks); leucite-based glassceramic (IPS Empress CAD); resin nano-ceramic (Lava Ultimate); and a control (intact teeth). After obtaining digital impressions, restorations were designed and milled with CAD/CAM. Inlay restorations were cemented to the inlay cavities using a dualpolymerizing resin cement (Rely X Ultimate) and stored in distilled water at 37°C for a week. All the samples were then exposed to accelerated ultraviolet aging for 300 hours. Finally, a compressive load was applied to the samples until fracture. Statistical analysis was conducted using One-Way ANOVA and the Tukey HSD test (?=0.05). Results: The mean fracture strength values of the groups were; Control (1555.3±412.2 N)> Lava Ultimate (1525±394N)>IPS Empress CAD (1364.3±545.6N) > CEREC(1231.9±412.2N), respectively. However, there was no statistically significant difference in mean fracture strength among different inlay restoration groups (P>0.05). Fifty percent of the both CEREC and IPS Empress CAD groups and 60% of the Lava Ultimate group showed reparable fractures. Conclusion: The type of material used did not influence the fracture strength of inlay-restored molar teeth and inlay restorations did not weaken the strength of the restored teeth. Therefore, all of the tested materials are suitable for use in the posterior region.Öğe Farklı Polisaj Yöntemleri Uygulanan Seramiklerde Yüzey Pürüzlülüğünün İncelenmesi(2001) Aykent, Filiz; İnan, Özgür; Üşümez, Aslıhan; Sevimay, MüjdeSeramik restorasyonlarda daimi simantasyondan sonra da okluzal uyumlama yapılması ve porselenin intraoral olarak polisajı gerekli olabilir. Bu nedenle porselenin intraoral olarak nasıl en ideal polisajının yapılabileceğini bilmek önemlidir. Ceramco, Vitadur-N, Ivoclar, In-Ceram ve Cerec (Pro-CAD) porselenlerinin kullanıldığı bu çalışmada; her porselen grubu için 1 x1 cm genişliğinde ve 1 mm kalınlığında 40'ar adet porselen örnek hazırlandı. Standart olarak tesviyeleri tamamlanan tüm örnekler 50\mu'luk AI2O3 kullanılarak kumlandı ve "ultrasonic cleaner"da temizlendi. Her porselen grubundaki örnekler 10'arlı 4 gruba ayrıldılar. 1. gruptaki örnekler EDENTA porselen polisaj kiti kullanılarak dakikada 15.000 devirli tur motorunda 60sn polisaj işlemine tabi tutuldu. 2. gruptaki porselenler ise her markanın talimatına uygun olarak glaze işlemine tabi tutuldu. 3. gruptaki örnekler ise 1dak. süre ile 2W gücündeki Nd:YAG lazer ışınlarına maruz bırakıldı. Son grup örnekler ise hiçbir işleme tabi tutulmadan kontrol grubu olarak bırakıldılar. Örneklerin Mitutuyo Surftest cihazı kullanılarak yüzey pürüzlülükleri ölçüldü. Sonuçlar ANOVA ve Tukey istatistik analizleri kullanılarak değerlendirildi. Tüm porselen tiplerinde glaze yapılan gruplar ile lastikle polisajı yapılan gruplar arasında fark bulunamadı (p0.05). Ancak lazer işlemine tabi tutulan gruplar, hem glaze hem de lastikle polisajı yapılan gruplardan daha pürüzlü bulundu (p0.05). Kontrol grubu örnekleri de diğer üç gruptan önemli ölçüde pürüzlü bulundu (p0.05). Porselen tipleri arasında ise Vitadur-N ve Ceramco diğer porselen çeşitlerinden daha pürüzlü bulundu (p0.05). Bunları sırasıyla Ivoclar, In-Ceram ve Cerec porselenleri izledi. Bu porselen tipleri arasında ise pürüzlülük yönünden fark bulunamadı (p0.05).
