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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., (© 2024. The Author(s), under exclusive licence to The Society of The Nippon Dental University.)

Objectives: This study aimed to evaluate the feasibility of monolithic zirconia laminate veneers (MZLV) compared to lithium disilicate laminate veneers (LDLV)., Materials and Methods: 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)., Results: 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., Conclusions: 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., Clinical Relevance: Considering clinical factors, MZLV may be a preferable option to LDLV for this restoration with the thickness of 0.5 mm., (© 2024. The Author(s).)

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 ∆E 00 value to measure colour stability, the translucency parameter (TP 00 ), 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 ∆E 00 , TP 00 , and CR parameters; the joint effect of resin groups, mouthwash groups, and measurement times were found to be statistically significant. The ∆E 00 (colour difference) parameter; the joint effect of resin groups, mouthwash groups, and measurement times was found to be statistically significant. The TP 00 ; 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., (© 2024. The Author(s).)

Ceramic laminate veneers which are a conservative approach to restoring anterior teeth, combining minimal preparation and esthetics . This study aims to evaluate the impact of the thickness of monolithic zirconia laminate veneers on their optical properties and color perception, comparing them to lithium disilicate. A total of 60 laminate veneers were prepared using two ceramic materials, divided into three groups for each material (n = 10) with thicknesses of 0.5, 0.7, and 1.0 mm. CIELab color parameters of the veneers were measured using a spectrophotometer and translucency parameters were calculated. The veneers were cemented onto uniform dies and final L, a, b values of the restorations were measured. The color difference between the different thicknesses was calculated using the CIEDE2000 formula. Two-way ANOVA and Bonferroni HSD post hoc tests were conducted to compare the color parameters (α = 0.05). The results showed that both material type (p < 0.001) and thickness (p < 0.001) influenced translucency values. The translucency values of zirconia veneers were significantly lower than those of lithium disilicate. The color differences (ΔE00) resulting from thickness changes (0.5-1.0 mm) were near or below the perception threshold for lithium disilicate, but distinct for zirconia restorations. In conclusion, monolithic zirconia veneers demonstrated lower translucency compared to lithium disilicate. Changing the material thickness affected the translucency of both materials, but not the color perception only for zirconia., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Objectives: Professionals in the health sector have higher stress than others. The aim of this study was to evaluate the stress levels of dentists while treating with children under clinical, deep sedation, and general anesthesia., Materials and Methods: Blood pressure (systolic, diastolic), pulse value, and O 2 saturations were measured. Saliva samples were taken by the dentists 10 min before the treatment, at the 25th min of the treatment, and 30 min after the treatment under clinical, deep sedation, and general anesthesia. Salivary cortisol was measured by the electrochemiluminescence method. All data were analyzed statistically., Results: Cortisol values under the sedation were higher than clinical and general anesthesia (P < 0.05). As a result of the applied Dentist Job Stress Questionnaire, the stress level of dentists under sedation was higher than the clinical and general anesthesia (P < 0.05). Under sedation, systolic and diastolic blood pressures measured during the procedure were found to be high (P < 0.05)., Conclusions: Dentists who care for pediatric patients are more stressed when applying treatment under deep sedation. The results suggest the need for more training and practice to strengthen the education given on general anesthesia/sedation in pediatric dentistry training., Clinical Revelance: To increase the health and treatment quality of the dentists, who spend most of the day with the dental treatment of children, should be taken precautions., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)