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Purpose: This in vitro study aimed to evaluate the effects of post material and cement type on the pull-out force of prefabricated glass-fiber, PEEK, and PEKK posts. Methods: Sixty extracted human mandibular premolars were prepared with standardized root canals and allocated into six groups (n = 10) according to post material (glass-fiber, PEEK, PEKK) and luting cement (resin or glass ionomer). PEEK and PEKK posts were CAD-CAM fabricated from prefabricated discs. All specimens underwent thermocycling (6000 cycles, 5–55 °C) prior to pull-out force testing on a universal testing machine, and failure modes were classified as adhesive, cohesive, or mixed. Because variance homogeneity was not satisfied, pull-out force values were logarithmically transformed (Log10) before two-way ANOVA and Bonferroni-adjusted post hoc analyses. Results: Post material (p = 0.026), cement type (p < 0.001), and their interaction (p = 0.012) significantly influenced pull-out force. Under resin cement, no statistically significant differences were detected among glass-fiber, PEEK, and PEKK posts. Under glass ionomer cement, PEEK and PEKK posts demonstrated significantly higher pull-out force than glass-fiber posts. The highest mean pull-out force was observed for glass-fiber posts luted with resin cement. The effect of post material on pull-out force was dependent on the luting cement. PEEK posts luted with resin cement showed no significant difference in pull-out force compared with conventional glass-fiber posts, supporting their potential as an alternative post material. Further studies are needed to evaluate the clinical performance of PEEK posts.

Aim: The aim of this study is to evaluate the effects of Er,Cr:YSGG laser debonding on the mechanical properties of aged and non-aged lithium disilicate ceramics. Material and Methods: A total of 36 lithium disilicate samples with dimensions of 14x4x1 mm were prepared. Half of the samples underwent 5000 thermal cycles to simulate artificial aging. The aged and non-aged samples were divided into two subgroups: one subgroup was designated as the control group and did not receive laser treatment, while the other subgroup was treated with Er,Cr:YSGG laser for debonding (n=9). The flexural strength and modulus of the lithium disilicate samples were assessed using three-point bending tests before and after artificial aging. The surface roughness of a sample that did not undergo the three-point bending test was measured with AFM, its microhardness was assessed using Vickers hardness tests, and surface morphology was examined with FESEM. Two-way ANOVA and Bonferroni correction to determine the significance of the results were used for statistical analysis. Results: The results indicated that aging significantly reduced the flexural strength (p=0.031), however, laser debonding did not have a significant effect on the flexural strength or modulus of either aged or non-aged samples. Conclusion: Laser debonding effectively removes lithium disilicate restorations without compromising their mechanical properties, supporting their reuse in clinical practice. It is important to note that aging reduces the flexural strength of lithium disilicate ceramics.

Aim: This study aims to evaluate the tensile bond strength (TBS) of a silicone-based soft denture liner material on denture bases produced via conventional, subtractive, and additive manufacturing techniques and examine the effect of aluminum oxide particle abrasion (APA) on TBS. Material and Methods: A total of 48 cylindrical denture base resin samples were manufactured using three different techniques: conventional, subtractive, and additive manufacturing. The samples were divided into two groups: control and APA. All samples were separated at the center, and the soft liner was applied to the corresponding surfaces. The specimens then underwent TBS testing. Data were analyzed using Two-way ANOVA and Bonferroni post hoc tests. Results: Two-way ANOVA results indicated a significant difference among the denture base resins, while no significant difference was found between the control and APA groups. The highest TBS was observed in the subtractive-manufactured APA group, while the lowest TBS was in the additive-manufactured APA group. Significant differences were found between the subtractive and additive-manufactured groups (p=0.022). Conclusion: This study demonstrates that TBS varies with the DB's manufacturing technique. While APA increased TBS in subtractive manufacturing, it had no statistically significant effect. Further research should explore different soft lining materials and consider in vivo conditions for more comprehensive insights.

This study aimed to evaluate the feasibility of monolithic zirconia laminate veneers (MZLV) compared to lithium disilicate laminate veneers (LDLV). Sixty resin replicas, each prepared with depths of 0.5 mm, 0.7 mm, and 1 mm, were produced using a 3D printer from acrylic teeth. Laminate veneers of these thicknesses were milled from pre-sintered monolithic zirconia (3rd generation) and lithium disilicate blocks. The intaglio surface of MZLV was treated with air abrasion using 110 μm diameter silica-modified aluminium oxide particles and ceramic primer, while LDLV was etched with etchant gel and treated with the ceramic primer before cementation with resin cement. Vertical marginal discrepancy (VMD) was assessed using a stereomicroscope, and a load-to-failure test was conducted using a universal testing machine. Failure modes were evaluated macroscopically on fractured surfaces. Data were analysed statistically using Two-way ANOVA and Bonferroni correction (α = 0.05). LDLV samples exhibited significantly larger VMD compared to MZLV samples across all thicknesses, especially in cervical, palatal, and mean data. Within the LDLV group, load-to-fracture values for 0.7 mm and 1.0 mm thicknesses were similar, whereas for 0.5 mm thickness, it was significantly lower. In the MZLV group, load-to-fracture values were lower for 0.7 mm and 1.0 mm thicknesses compared to LDLV, but higher for 0.5 mm thickness. Material choice and restoration thickness significantly influence laminate veneer restorations’ success. MZLV generally exhibits superior vertical marginal fit compared to LDLV, with varying load-to-failure values across different thicknesses. Clinical management of debonding in MZLV is simpler compared to restoration fracture in LDLV. Considering clinical factors, MZLV may be a preferable option to LDLV for this restoration with the thickness of 0.5 mm.

The purpose of this study was to investigate the vertical marginal discrepancy (VMD) and residual excess cement (REC) of cementable and screwmentable monolithic zirconia crowns cemented with different types of cement. Abutments were attached to 40 implant analogues. Crowns were created using computer-aided design/computer-aided manufacturing technology from monolithic zirconia blocks, either with or without a screw access hole (SAC). Crowns created both ways were split into two groups and cemented with resin and zinc polycarboxylate cement under a 5-kg weight. VMD and REC values were evaluated using an X20 zoom stereomicroscope. Data were analysed using two-way ANOVA and the Bonferroni test. According to the two-way ANOVA results, REC measurements differed significantly in the crown design and cement groups. However, whilst VMD values were significantly different in both crown design groups, there was no significant difference in the cement groups. According to the Bonferroni test results, the highest REC (157.241 ± 44.29 µm) and VMD (68.052 ± 16.19 µm) values were found in the crowns without SAC and cemented with zinc polycarboxylate. Screwmentable crowns are more effective than cementable crowns in reducing REC and VMD. Whilst polycarboxylate cement reduces VMD in screwmentable crowns, resin cement is more suitable for cementable crowns.

Objectives: The objective of this study was to evaluate the effect of mouthwashes on the optical properties of resin cement. Materials and methods: One hundred and 60 resin cement discs (6x2mm) were produced from 4 different brands of resin cement (Panavia V5, Estecem II, RelyX Veneer, NX3) with the help of a Teflon mould. The discs were divided into 4 subgroups, 1 of which served as the control group, to be immersed in mouthwashes after measuring the initial L, a, and b values on white and black backgrounds. Colour measurements were repeated after the 1st and 7th days. The collected data were used to calculate the ∆E₀₀ value to measure colour stability, the translucency parameter (TP₀₀), and the contrast ratio parameter (CR) to compare translucency change. Data were statistically analysed using mixed-design analysis of ANOVA and the Bonferroni-Dunn test. Repeated measures ANOVA was used for dependent results (α = 0.05). Results: On the ∆E₀₀, TP₀₀, and CR parameters; the joint effect of resin groups, mouthwash groups, and measurement times were found to be statistically significant. The ∆E₀₀ (colour difference) parameter; the joint effect of resin groups, mouthwash groups, and measurement times was found to be statistically significant. The TP₀₀; the joint effect of resin groups, mouthwash groups, and measurement times were found to be statistically significant. The CR parameter; the joint effect of resin groups, mouthwash groups, and measurement times was found to be statistically significant. In the Estecem II (Tokuyama) group, the means of Listerine Cool Mint (Johnson & Johnson) was above acceptable limits in both time periods. In the Panavia V5 (Kuraray Noritake) group, the color change was above acceptable limits in all time periods and in all mouthwash groups. Among the resin materials used, Estecem II (Tokuyama) shows the most color change. Listerine Cool Mint (Johnson & Johnson) caused more color change than other mouthwashes at all times. Conclusions: Within the limitations of this study; the colour stability and translucency value of resin cement depend on both the resin cement content and the mouthwash. Long-term use of mouthwash may adversely affect the optical properties of the resin cement. Clinical relevance: Clinicians should take into account the fact that mouthwash use and the composition of the resin cement employed will have an impact on the colour of laminate veneers.

This study was purposed to assess the impact of ageing and resin cements polymerized with different modes on the removal time of lithium disilicate (LiSi) ceramics using Er,Cr:YSGG laser. Ninety LiSi slabs (6 × 6 × 1 mm) were cemented to freshly extracted bovine teeth using cements polymerized with different modes (light-curing (LC), dual-curing (DC), self-curing (SC)). The specimens were divided into subgroups according to ageing conditions (no thermal cycling, 5000 or 30,000 thermal cycling). After that, Er,Cr:YSGG laser was applied until LiSi slabs were debonded; the removal time was recorded. Vickers microhardness test, SEM and EDS analyses were performed for specimens with the longest exposure time to laser application in the groups. One uncemented sample was also used as a control. Data were analyzed with two-way ANOVA and Tukey post hoc test. Ageing and cement polymerization mode significantly affected the removal time of LiSi specimens. The removal time for the self-curing resin cement group (22.67 ± 12.68 s) was significantly longer than for cements polymerized with other methods (LC = 10.833 ± 7.28 s, DC = 12.0 ± 7.96 s). Removal time was significantly reduced after ageing in all polymerization modes; however, there were no significant differences between 5000 (11.83 ± 7.52 s) and 30,000 (11.83 ± 7.26 s) thermal cycling groups. Self-curing resin cements had prolonged the laser-aided removal time for LiSi ceramics. It can be concluded that Er,Cr:YSGG laser-aided removal of LiSi veneers after clinical use can be done more faster than its immediate removal.

Akademisyen Yayınevi yöneticileri, yaklaşık 30 yıllık yayın tecrübesini, kendi tüzel kişiliklerine aktararak uzun zamandan beri, ticarî faaliyetlerini sürdürmektedir. Anılan süre içinde, başta sağlık ve sosyal bilimler, kültürel ve sanatsal konular dahil 1000 kitabı yayımlamanın gururu içindedir. Uluslararası yayınevi olmanın alt yapısını tamamlayan Akademisyen, Türkçe ve yabancı dillerde yayın yapmanın yanında, küresel bir marka yaratmanın peşindedir. Bilimsel ve düşünsel çalışmaların kalıcı belgeleri sayılan kitaplar, bilgi kayıt ortamı olarak yüzlerce yılın tanıklarıdır. Matbaanın icadıyla varoluşunu sağlam temellere oturtan kitabın geleceği, her ne kadar yeni buluşların yörüngesine taşınmış olsa da, daha uzun süre hayatımızda yer edineceği muhakkaktır. Gülüş Tasarımında Estetik Kriterler Merve ÜNAL Aysıla ŞİMSEK TEKELİ Gamze PAKEN Bengisu YILDIRIM Diş Hekimliğinde Güncel Estetik Materyaller Aysıla ŞİMSEK TEKELİ Merve ÜNAL Bengisu YILDIRIM Gamze PAKEN Dental Ölçülerin Dezenfeksiyonu Pınar YILDIZ İntraoral Dijital Ölçü Teknikleri Sevil Meral ŞAHMALI Münir DEMİREL Endodontik Tedavili Dişlerde Protetik Yaklaşımlar Mustafa Borga DÖNMEZ Sabit Protetik Restorasyonlarda Kullanılan Metal Alt Yapı Üretim Yöntemleri Mehmet BİÇER Server MUTLUAY ÜNAL Lityum Disilikat Cam Seramik Sistemleri: Son Güncellemeler Gonca DESTE Tam Seramik Restorasyonlarda Görülen Başarısızlıklar Işıl KARAOKUTAN İmplantüstü Protezlerde Yükleme Protokolleri Melahat Çelik Güven İmplant Destekli Protezlerde Okluzyon Damla GÜNEŞ ÜNLÜ Oklüzal Dikey Boyut Kayıplarının Protetik Açıdan Değerlendirilmesi Sadeq Mohammed Taqi FADHİL Emre MUMCU Hareketli Protezlerin Temizlenmesinde Kullanılan Materyal ve Yöntemler Zeynep YEŞİL DUYMUŞ Sebahat FINDIK AYDINER Maksillofasiyal Protezlerde Kullanılan Materyallere Genel Bakış ve Güncel Teknikler Almira Ada DİKEN TÜRKSAYAR

= 22/canine = 3) were enrolled in this study (18 immediate loading and 15 late loading). At after cementation, 1, 3, 6, and 12 months photographs were taken of anterior maxilla. The photographs were assessed using pink esthetic score (PES) which consists of seven variables. All PES data were analyzed with independent sample t-tests and repeated measures ANOVAs. Results: PES values increased significantly in both groups at the 1-year follow-up (P > 0.05). There was no statistically significant difference between the immediate and late loading groups at any time point (P > 0.05). Conclusions: Within the limitation of this study, immediate loading did not have a negative effect on esthetics....

When selecting appropriate patients (adequate primary stability, patient compliance with the surgeon's recommendations), immediate implant loading may be an alternative method to late loading protocol for replacement of a missing tooth in anterior maxilla.