Person: TUNCEL, İLKİN
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- PublicationOpen AccessEffects of coloring procedures on shear bond strength between resin cement and colored zirconia.(2018-09-01) TUNCEL, İLKİN; Turp, IŞIL; TUNCEL, İLKİN; TURP, IŞILZirconia has a high fracture strength of more than 1000 MPa, fracture resistance of higher than 2000 N, and fracture toughness of 9–10 MN/m3/2 (1). In addition to these favorable mechanical properties, it is chemically durable (2), biocompatible (3, 4), and displays esthetic advantages (5) over metal-ceramic restorations. However, recent clinical trials have shown that zirconia-based ceramic restorations’ decementation is a common failure. Restoration’s cementation corresponds to restoration durability, and cementation is also an important factor for marginal fit and fracture strength of restorations (6, 7). There are various cementation options for zirconia framework restorations. Cementation of zirconia restorations with traditional luting cements (such as glass ionomer or zinc phosphate cements) provides adequate clinical fixation, but adhesive cementation may be preferred for better retention and marginal adaptation (7-10). In addition, resin cement shows higher compressive and tensile strength than other luting agents, and allows color selection for more esthetic restorations (11, 12).
- PublicationMetadata onlyBond strength of short-pulsed laser-irradiated zirconia to veneer ceramic(2015-06-01T00:00:00Z) Tuncel, Ilkin; TURP, IŞIL; Usumez, Aslihan; TUNCEL, İLKİN; TURP, IŞILObjective: The aim was to evaluate the effect of 1064nm Yb-doped fiber-based nanosecond pulsed laser on surface roughness and bond strength between veneer ceramic and zirconia. Material and methods: Zirconia discs were divided into three groups: sandblasted (SB), laser irradiated (YL), and control (n = 12). YL group was treated with ytterbium laser with the setting of 85W/25kHz. Sandblasting was done using 50 mu m Al2O3 particles from a distance of 10mm for 20s under 3.5atm. No surface treatment was applied to the control group. The surface roughness values and SEM images of the groups were obtained. X-ray diffraction analysis was applied to a spare sample of each group to determine the monoclinic phase ratio. The samples were subjected to shear bond strength (SBS) test with a cross-head speed of 1mm/min after being veneered. The fracture modes were evaluated. One-way analysis of variance and Tukey-s HSD tests were used for statistical analysis. Results: The YL group had higher surface roughness than the control (p <= 0.0001) and the SB group (p = 0.007) with a mean value of 2.90 mu m. The SEM images of the groups supported this result, but formation of the microcracks was more intense for the YL group. The monoclinic phase ratio was highest for the SB group. However, the differences of SBS between SB and YL groups were not statistically significant. Mostly the combined failure of samples was observed. Conclusions: Ytterbium laser treatment increased the surface roughness of zirconia, but the SBS was not higher than sandblasting. Surface roughness results did not correlate with the SBS results.
- PublicationMetadata onlyThe Effect of Luting Cement and Titanium Base on the Final Color of Zirconium Oxide Core Material(2017-02-01T00:00:00Z) ÇAPA, NURAY; TUNCEL, İLKİN; Tak, Onjen; Usumez, Aslihan; TUNCEL, İLKİNPurposeTo evaluate the effects of different types of luting cements and different colors of zirconium cores on the final color of the restoration that simulates implant-supported fixed partial dentures (FPDs) by using a titanium base on the bottom.
- PublicationMetadata onlyMetal-Seramik Restorasyonlarda Fırınlama Sayısı ve Seramik Kalınlığının Renk Değişimine Etkisi(2017-12-01) TUNCEL, İLKİN; TURP, IŞIL; DÜÇ, Buğra; SELÇUKER, Ahmet Hamdi; ASLANTAŞ, Akif; BEKMAN, Enes; TUNCEL, İLKİN; TURP, IŞIL
- PublicationMetadata onlyFarklı Işık Kaynakları Altında Öğrencilerin Renk Seçimi Değerlendirmesi(2017-11-12) TUNCEL, İLKİN; OCAK ÇİMENDUR, ÖZLEM; TURP, IŞIL; TUNCEL, İLKİN; OCAK ÇİMENDÜR, ÖZLEM; TURP, IŞIL
- PublicationMetadata onlyThe effect of coloring liquids on the translucency of zirconia framework(2013-11-01T00:00:00Z) TUNCEL, İLKİN; EROĞLU, Erdal; Sari, Tugrul; Usumez, Aslihan; TUNCEL, İLKİNPURPOSE. Translucency of all-ceramic restorations is an important factor which affects the final appearance and esthetic outcome of the restoration. The aim of this study was to evaluate the effect of the shade of coloring liquid on the translucency of zirconia framework. MATERIALS AND METHODS. Thirty zirconium oxide core plate (15 x 12 x 0.5 mm) were divided into 6 groups of 5 plates each. Each group was classified according to the shade of coloring liquid based on Vita Classic Scale (A2, A3, B1, C2, and D2), and each sample was immersed in coloring liquid for 3 seconds as recommended by the manufacturer, except for the control group. Contrast ratio, as a translucency parameter, was calculated using a spectrophotometer and the data were analyzed with one-way analysis of variance (ANOVA) and Tukey-s honestly significant differences (HSD) tests (alpha=.05). RESULTS. Significant differences in translucency among the control and test groups, and the B1 shaded group and other shades was observed. There were no significant differences among A2, A3, C2, and D2 shaded groups. CONCLUSION. The translucency of the zirconium oxide cores was affected by the coloring procedure and significant differences in the translucency measurements were identified between specific shades.
- PublicationMetadata onlyFarklı İçerik ve Kalınlıktaki Tam Seramik Restorasyonların Translusentlik Değerlerinin Karşılaştırılması(2017-10-01) TUNCEL, İLKİN; TURP, IŞIL; TUNCEL, İLKİN; TURP, IŞIL
- PublicationMetadata onlyTransmission of Er:YAG Laser Through Different Dental Ceramics(2014-01-01T00:00:00Z) Sari, Tugrul; TUNCEL, İLKİN; Usumez, Aslihan; Gutknecht, Norbert; TUNCEL, İLKİNObjective: The aim of this study was to determine the erbium-doped yttrium aluminum garnet (Er:YAG) laser transmission ratio through different dental ceramics with different thicknesses. Background data: Laser debonding procedure of adhesively luted all-ceramic restorations is based on the transmission of laser energy through the ceramic and the ablation of resin cement, because of the transmitted laser energy. Methods: Five different dental ceramics were evaluated in this study: sintered zirconium-oxide core ceramic, monolithic zirconium-oxide ceramic, feldspathic ceramic, leucite-reinforced glass ceramic, and lithium disilicate-reinforced glass ceramic. Two ceramic discs with different thicknesses (0.5 and 1mm) were fabricated for each group. Ceramic discs were placed between the sensor membrane of the laser power meter and the tip of the contact handpiece of an Er:YAG laser device with the aid of a custom- made acrylic holder. The transmission ratio of Er:YAG laser energy (500mJ, 2Hz, 1W, 1000s) through different ceramic discs was measured with the power meter. Ten measurements were made for each group and the results were analyzed with two way analysis of variance (ANOVA) and Tukey honestly significant difference (HSD) tests. Results: The highest transmission ratio was determined for lithium disilicate-reinforced ceramic with 0.5mm thickness (88%) and the lowest was determined for feldspathic ceramic with 1mm thickness (44%). The differences among the different ceramics and between the different thicknesses were significant (p<0.05). Conclusions: Ceramic type and thickness should be taken into consideration to adjust the laser irradiation parameters during laser debonding of adhesively luted all-ceramic restorations.
- PublicationOpen AccessEvaluation of translucency of monolithic zirconia and framework zirconia materials.(2016-06-01) TUNCEL, İLKİN; Turp, IŞIL; USUMEZ, A; TUNCEL, İLKİN; TURP, IŞILPURPOSE. The opacity of zirconia is an esthetic disadvantage that hinders achieving natural and shade-matched restorations. The aim of this study was to evaluate the translucency of non-colored and colored framework zirconia and monolithic zirconia. MATERIALS AND METHODS. The three groups tested were: non-colored framework zirconia, colored framework zirconia with the A3 shade according to Vita Classic Scale, and monolithic zirconia (n=5). The specimens were fabricated in the dimensions of 15×12×0.5 mm. A spectrophotometer was used to measure the contrast ratio, which is indicative of translucency. Three measurements were made to obtain the contrast ratios of the materials over a white background (L*w) and a black background (L*b). The data were analyzed using the one-way analysis of variance and Tukey HSD tests. One specimen from each group was chosen for scanning electron microscope analysis. The determined areas of the SEM images were divided by the number of grains in order to calculate the mean grain size. RESULTS. Statistically significant differences were observed among all groups (P<.05). Non-colored zirconia had the highest translucency with a contrast ratio of 0.75, while monolithic zirconia had the lowest translucency with a contrast ratio of 0.8. The mean grain sizes of the noncolored, colored, and monolithic zirconia were 233, 256, and 361 nm, respectively. CONCLUSION. The translucency of the zirconia was affected by the coloring procedure and the grain size. Although monolithic zirconia may not be the best esthetic material for the anterior region, it may serve as an alternative in the posterior region for the bilayered zirconia restorations. [J Adv Prosthodont 2016;8:181-6]
- PublicationOpen AccessEffect of color shading procedures and cyclic loading on the biaxial flexural strength of zirconia.(2018-01-01) TUNCEL, İLKİN; Turp, IŞIL; USUMEZ, A; TUNCEL, İLKİN; TURP, IŞILPurpose: Zirconia is the most preferred ceramic restoration in posterior areas because of its flexural strength. The aim of the study is the evaluation of biaxial flexural strength of different colored zirconium oxide core materials after cyclic loading. Material and Methods: Zirconia discs (12 mm diameter and 1.2 mm thickness) were divided into 6 groups of 12 discs each. Groups were colored according to the Vita Classic shade guide: A3 and D4. One group was not colored and left as control. Each group was randomly divided into subgroups and subjected to mechanical cycling prior to biaxial flexural strength test. Cyclic loading was applied as 50 N loads for 20,000 times for the loaded groups. Samples were subjected to biaxial flexural strength test in a universal testing machine with a crosshead speed of 1 mm/min. Two-way analysis of variance (ANOVA) and Tukey's HSD tests were used for comparisons of the groups. Results: Biaxial flexural strength values did not vary significantly depending on coloring procedure or loading process tested (p>.05). XRD analysis displayed that the monoclinic volume fraction of zirconia was highest in cyclic loaded D4 and was lowest in non-loaded control group. The SEM image revealed that A3 color solution created metallic coloring pigments at grain boundaries. Conclusions: Coloring procedures and cyclic loading did not affect the biaxial flexural strength of zirconia core material; however, microstructural analysis displays changes, which may weaken the zirconia structure on the long term.