Person: DALKILIĆ, EVRIM
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Publication Open Access Effect of polymerization time and home bleaching agent on the microhardness and surface roughness of bulk-fill composites: A scanning electron microscopy study(2019-01-01T00:00:00Z) ĆZDUMAN, ZĆMRĆT CEREN; Kazak, Magrur; FÄ°LDÄ°ÅÄ°, MEHMET ALÄ°; ĆZLEN, RĆMEYSA HATÄ°CE; DALKILIĆ, Evrim; DĆNMEZ, NAZMÄ°YE; ĆZDUMAN, ZĆMRĆT CEREN; FÄ°LDÄ°ÅÄ°, MEHMET ALÄ°; ĆZLEN, RĆMEYSA HATÄ°CE; DALKILIĆ, EVRIM; DĆNMEZ, NAZMÄ°YEObjective: The aim of this study is to evaluate the microhardness and surface roughness of two different bulk-fill composites polymerized with light-curing unit (LCU) with different polymerization times before and after the application of a home bleaching agent. Materials-methods: For both microhardness and surface roughness tests, 6 groups were prepared with bulk-fill materials (SonicFill, Filtek Bulk Fill) according to different polymerization times (10, 20, and 30 s). 102 specimens were prepared using Teflon molds (4 mm depth and 5 mm diameter) and polymerized with LCU. 30 specimens (n = 5) were assessed for microhardness. Before home bleaching agent application, the bottom/top (B/T) microhardness ratio was evaluated. After bleaching agent application, the microhardness measurements were performed on top surfaces. Roughness measurements were performed in 72 specimens (n = 12) before and after bleaching application. Additionally, for SEM analyses, two specimens from all tested groups were prepared before and after bleaching agent application. The data B/T microhardness ratio before bleaching was analyzed by two-way ANOVA and Tukey's HSD test. The data from the top surface of specimens' microhardness before and after bleaching were analyzed using Wilcoxon signed-rank test, Kruskal-Wallis, Mann-Whitney U tests. The data from surface roughness tests were statistically analyzed by multivariate analysis of variance and Bonferroni test (p < 0.05). Results: The B/T microhardness ratio results revealed no significant differences between groups (p > 0.05). Comparing the microhardness values of the composites' top surfaces before and after bleaching, a significant decrease was observed exclusively in FB30s (p < 0.05). No significant differences in surface roughness values were observed when the groups were compared based on bulk-fill materials (p > 0.05) while the polymerization time affected the surface roughness of the SF20s and SF30s groups (p < 0.05). After bleaching, surface roughness values were significantly increased in the SF20s and SF30s groups (p < 0.05). Conclusion: The clinicians should adhere to the polymerization time recommended by the manufacturer to ensure the durability of the composite material in the oral environment.Publication Metadata only Effect of titanium dioxide nanotubes on the mechanical and antibacterial properties of the low-viscosity bulk-fill composite(2021-10-01T00:00:00Z) ĆZLEN, RĆMEYSA HATÄ°CE; DALKILIĆ, Evrim; KĆĆĆKYILDIRIM, Bedri Onur; AKDOÄAN EKER, AyÅegĆ¼l; Topcuoglu, Nursen; Kulekci, Guven; ĆZLEN, RĆMEYSA HATÄ°CE; DALKILIĆ, EVRIMThe purpose of this investigation is to determine the impact of titanium dioxide nanotubes (TiO2-n) on the mechanical and antibacterial properties of bulk-fill composite resin. TiO2-n were synthesized in laboratory conditions using the hydrothermal method. Varying amounts of TiO2-n were included in the bulk-fill composite resin. Microhardness, surface roughness, and the three-point bending test were used to determine the mechanical properties of the composite. After the flexural strength test, the fractured surfaces of the composite resin were examined with a high-resolution scanning electron microscope. The antibacterial activity of Streptococcus mutans (S.mutans) and Lactobacillus Casei (L.casei) was assessed using a direct contact test. The statistical examination was completed using IBM SPSS Statistics 22. Group differences were compared using the Kruskal Wallis and Dunn tests (p 0.05). Adding 0.5% and 1% TiO2-n increased the microhardness of the bulk-fill composite (p 0.05). Though adding TiO2-n did not have an antibacterial impact on S.mutans (p > 0.05), adding 0.5% TiO2-n produced an antibacterial impact on L.casei in daylight (p < 0.05). The addition of 0.5% and 1% TiO2-n increased the microhardness of the top surface of the bulk-fill composite without negatively affecting surface roughness or the composite-s three-point bending properties Adding 0.5% TiO2-n to the composite resin produced an antibacterial impact on L.casei in daylight.Publication Metadata only An Alternative Adhesive Strategy to Optimize Bonding to Root Dentin(2011-10-01T00:00:00Z) Belli, Sema; Cobankara, Funda Kont; Ozcopur, Betul; Eliguzeloglu, EVRÄ°M; Eskitascioglu, Gurcan; DALKILIĆ, EVRIMIntroduction: 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)Publication Metadata only Effect of different disinfectant methods on the initial microtensile bond strength of a self-etch adhesive to dentin(2012-07-01T00:00:00Z) Arısu, Hacer Deniz; DALKILIĆ, EVRÄ°M; Kivanc, Bagdagul Helvacioglu; Uctasli, Mine Betul; ĆmĆ¼rlĆ¼, HĆ¼ma; DALKILIĆ, EVRIMThe aim of this in vitro study was to evaluate the effect of different disinfection methods on the initial microtensile bond strength of a two-step, self-etch adhesive to dentin. Twenty mandibular molars were sectioned parallel to the occlusal plane to expose the mid-coronal dentin. All of the teeth were divided into four groups (n = 5 per group): (1) in group OZ, the dentin surfaces were exposed to ozone gas from the Ozonytron X delivery system (OzonyTron X-Bioozonix, Munich, Germany), (2) in group ND, the dentin surfaces were irradiated with an Nd:YAG laser (Pulsmaster 600 IQ, American Dental Technologies, U.S.), (3) in group CHX, the dentin surfaces were treated with a 2% chlorhexidine solution, and (4) in the control group, no treatment was applied. In all of the groups, the teeth were restored with Clearfil SE Bond (Kuraray, Tokyo, Japan) and Clearfil Majesty Posterior (Kuraray, Tokyo, Japan), according to the manufacturer-s instructions. The teeth were sectioned perpendicular to the bonded surface (surface area of approximately 1 mm(2)). Thus, six to seven specimens were obtained from each tooth, and a total of 34 specimens were analyzed in each group. The specimens were attached to the microtensile test machine (Micro Tensile Tester, T-61010 K, Bisco, U.S.). The data was analyzed using the one-way analysis of variance (ANOVA) and Tukey test (p < 0.05). Fracture modes of each specimen were determined using a stereomicroscope (SZ-PT Olympus, Tokyo, Japan) and a scanning electron microscope (SEM). The lowest bond strength occurred in the OZ group. Significant differences were determined only between group OZ and the other groups (group ND, group CHX, and control group) (p < 0.05). In conclusion, although ozone decreased the microtensile bond strength of the self-etch adhesive system to dentin, the Nd:YAG laser and 2% chlorhexidine did not change the microtensile bond strength so in context of the present study it would appear that the Nd:YAG laser and 2% chlorhexidine may be used as pre-restorative sterilization procedures on the dentin prior to the application of a two-step, self-etch adhesive.Publication Metadata only Influence of bulk-fill composite types, shades and light-curing units on microhardness(2020-05-01T00:00:00Z) Ćzdemir, Serife; DalkılıƧ, Evrim; ĆZDEMÄ°R, ÅERÄ°FE; DALKILIĆ, EVRIMPublication Metadata only Influence of fiber insertion and different material type on stress distribution in endocrown restorations: a 3D-FEA study.(2021-12-29T00:00:00Z) Yildirim, Gulhan; Demir, Cihan; GĆ¼ven, Melahat Ćelik; KoƧ, Osman; DalkiliƧ, Evrim; DALKILIĆ, EVRIMPublication Metadata only Volumetric change and gap formation in class V composite restorations: a micro-CT analysis(2020-07-01T00:00:00Z) OÄLAKĆI, Burcu; Halacoglu, Derya Merve; ĆZDUMAN, ZĆMRĆT CEREN; Dalkilic, Evrim; OÄLAKĆI, BURCU; ĆZDUMAN, ZĆMRĆT CEREN; DALKILIĆ, EVRIMThisin vitrostudy evaluated the volumetric change (VC) and gap formation (GF) in Class V composite restorations after light-curing and aging. Thirty-six extracted human premolars were used. Standardized Class V cavities (3 mmx3 mmx1.5 mm) were prepared. G-Premio Bond was applied. The teeth were randomly assigned into six groups (n = 6): Group FZ: Filtek Z250(microhybrid), Group SP: SDR Plus Bulk Fill Flowable (low-viscosity bulk-fill), Group EB: Estelite Bulk Fill Flow (low-viscosity bulk-fill), Group GI: G-aenial Universal Injectable (highly-filled low-viscosity), Group AF: Admira Fusion (ormocer), Group SX: Solare X (nanohybrid). Each specimen was scanned four times with micro-CT (SkyScan 1174v2, Belgium): after cavity preparation, before and after light-curing, and after aging. The VC (%) and GF (mm(3)) parameters were quantified and analysed. Then, VC after light-curing was verified with AcuVol video image analyser (n = 6). The specimens were submitted to 10,000 thermocycles (5-55 degrees C) and 100,000 load cycles (50N). The data were statistically analysed using the Kruskal-Wallis, Wilcoxon and Dunn tests (p < 0.05). After light-curing, Group AF and FZ showed significantly lower VC than Group GI. Group GI showed significantly higher total GF than Group AF, EB, FZ and SX. Group GI showed significantly higher GF than Group AF, EB and FZ in cervical region. After aging, a significant increase in the volume of the gap (VG) in cervical region was found for Group FZ and GI (p < 0.05). After light-curing, ormocer and microhybrid composites exhibited lower VC and GF than highly-filled low-viscosity composites. After aging, an increase in VG was observed for microhybrid and highly-filled low-viscosity composites for cervical region.Publication Metadata only The effect of fiber insertion on fracture strength and fracture modes in endocrown and overlay restorations.(2021-12-29T00:00:00Z) Fildisi, Mehmet Ali; Eliguzeloglu Dalkilic, Evrim; DALKILIĆ, EVRIMPublication Metadata only The Effect of Curing Modes and Times of Third-Generation Led LCU on the Mechanical Properties of Nanocomposites(2022-09-01T00:00:00Z) OÄLAKĆI, Burcu; Ozlen, Rumeysa Hatice Enginler; DEMÄ°RKOL, Metehan; ĆZDUMAN, ZĆMRĆT CEREN; KĆĆĆKYILDIRIM, Bedri Onur; DALKILIĆ, Evrim; OÄLAKĆI, BURCU; ĆZDUMAN, ZĆMRĆT CEREN; DALKILIĆ, EVRIMThis study evaluates the effect of curing modes and times on the mechanical properties of nanocomposites. Two nanocomposite resins were investigated: supra-nanohybrid (Estelite Posterior Quick; EP) and nanohybrid (Solare X; SX). They were polymerized with a light-emitting diode light-curing units (LED LCU, Valo) as follows: standard mode for 20s (ST20), high power mode for 12s (HP12), high power mode for 20s (HP20), extra power mode for 6s (XP6), and extra power mode for 20s (XP20). For Vickers microhardness (HV), disc-shaped specimens were fabricated (n=10). For the three-point bending test, bar-shaped specimens were fabricated (n=10). Flexural strength and resilience modulus were calculated. The fractured surfaces and specimen surfaces of composites were observed using scanning electron microscopy. The data were analyzed with repeated measures ANOVA, two-way variance, and Bonferroni tests (p<0.05). On the top and bottom surfaces of the EP nanocomposite resin, ST20 and HP12 revealed statistically higher HV than with XP6. Moreover, HP20 and XP20 had statistically higher HV than HP12 and XP6. For the SX nanocomposite resin, HP20 had statistically higher HV than HP12. For EP and SX, there were no significant differences in flexural strength and resilience modulus regarding the curing modes and times. Furthermore, SX demonstrated lower mechanical properties than EP. Scanning electron microscopy indicated that both nanocomposites had similar surface appearances. However, with all curing modes and times, SX exhibited layered fractures and more crack formations than EP. Different curing modes and times could influence the microhardness of nanocomposites.Publication Metadata only Profilaktik Polisaj Protokollerinin Farklı Rezin Kompozitlerin YĆ¼zey PĆ¼rĆ¼zlĆ¼lĆ¼ÄĆ¼ Ćzerine Etkisi(2021-12-01T00:00:00Z) OÄlakƧı, Burcu; FazlıoÄlu, Leyla; Ćzduman, ZĆ¼mrĆ¼t Ceren; DalkılıƧ, Evrim; OÄLAKĆI, BURCU; FAZLIOÄLU, LEYLA; ĆZDUMAN, ZĆMRĆT CEREN; DALKILIĆ, EVRIM