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Objectives: The aim of the study was to investigate the effects of various self-adhesive resin cements on the push-out bond strengths and nanoleakage expression at the luting interfaces of fiber posts immediately and after one year of aging. Methods and Materials: One hundred forty-four extracted human anterior teeth were endodontically treated. After post space preparation, fiber posts were luted using five commercially available self-adhesive resin (SAR) cements and a core build-up material applied with a self-etch adhesive (BF: Bifix SE/Rebilda Post, VOCO; CSA: Clearfil SA Cement/Rely X Fiber Post, 3M ESPE; RX: RelyX Unicem 2/Rely X Fiber Post, 3M ESPE; SPC: Speed Cem/FRC Postec, Ivoclar Vivadent; SMC: Smart Cem/X Post, Dentsply; RB: Rebilda DC-Futurabond/Rebilda Post; n=22). For each group, half of the specimens were subjected to thermocycling (TC) (5°C-55°C, 10,000 cycles) and stored humid for one year at 37°C. Push-out bond strength data of six slices (thickness 1 mm) per root and nanoleakage expression of representative specimens were evaluated after 24 hours (baseline) and after TC and storage for one year (aging), respectively. Results: Bond strength differed significantly among resin cements (p<0.0005) and the location inside the root canal (p<0.0005), but not by aging (p=0.390; repeated-measures analysis of variance). SMC (14.6±5.8 MPa) and RX (14.1±6.8 MPa) revealed significantly higher bond strength compared to BF (10.6±5.4 MPa) and RB (10.0±4.6 MPa) but differed not significantly from SPC (12.8±4.8) MPa; CSA (6.1±4.6 MPa) revealed significantly lower bond strength compared to all other investigated materials (p<0.05; Tukey Honestly Significantly Different). Qualitative nanoleakage analysis revealed more silver deposits at the interface in all groups after aging. For CSA, a large amount of silver deposits inside the cement was also observed at baseline and after aging. Conclusions: Fiber post luting using SAR cements demonstrated reliable bond strengths. Product-specific differences and initial degradation effects could be demonstrated. [ABSTRACT FROM AUTHOR]

Wear phenomena of ceramic inlays are not fully understood. The aim of the present study was to evaluate ceramic wear, antagonist enamel wear, and luting cement wear over 8 years. The two-fold null hypothesis was that there would be (1) no difference in wear behavior between ceramic and enamel, and (2) no influence of filler content of luting composites on composite wear. From 96 restorations, 36 Class II inlays from 16 participants were selected. For inlays with opposing enamel cusps (n=17), replicas of inlays and enamel were scanned with a 3-D laser scanner. Luting gaps of inlays (n=36) were analyzed with a profilometer, including 3-D data analysis. Ceramic and enamel wear increased between 4 and 8 years, with significantly higher values for enamel after 6 years (p<0.05). Luting gap wear increased continuously up to 8 years (p<0.05), with no influence of luting composites (p>0.05) and location of teeth (p>0.05). [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate ceramic wear, antagonist enamel wear, and luting cement wear over 8 years. The 2-fold null hypothesis was that there would be (1) no difference in wear behavior between ceramic and enamel and (2) no influence of filler content of luting composites on composite wear. Seventeen inlays and their corresponding antagonists in 10 patients were included to test the first hypothesis. Criteria for inclusion were as follows: (1) the restorative situation of the antagonist and adjacent teeth had to be unchanged over the whole period, and (2) the contact area of the ceramic inlay had to be exclusively in enamel. Dies in Fuji Rock were made from impressions made at recall sessions at 6 months, 1 year, and 2, 4, 6, and 8 years. One-year assessments were defined as baseline, with 4-, 6-, 8-year dies serving as follow-up. Dies were scanned with a 3-dimensional laser scanner. Thirty-six inlays (with cusp inclinations below 45 degrees) from 16 patients were selected to test the second hypothesis. Twenty of these inlays were luted with a light-cured hybrid-type resin composite (filler 82 wt %), and 16 were luted with a dual-cured luting composite Variolink Low (filler 72 wt %). Three-dimensional scanning of luting gaps was done using a profilometer. Occlusal contact areas were excluded from the measurement. Data concerning the comparison of ceramic versus antagonist wear were normally distributed (Kolmogorov-Smirov test) and were therefore analyzed with paired t tests. Significant changes in wear were computed using Friedman 2-way analysis of variance (ANOVA) (P = .05). Differences between groups in the luting gap analysis were evaluated using pair-wise with the Mann-Whitney U test (P = .05). Differences over the investigation period were calculated using Friedman 2-way ANOVA. Linear regression analysis was used to assess the correlation between width and depth of the luting gap. Ceramic and enamel wear increased between 4 and 8 years, with significantly higher values for enamel after 6 years (P < .05). Luting gap wear increased continuously up to 8 years (P < .05), with no influence of luting composites (P < .05) or location of teeth (P < .05). [ABSTRACT FROM AUTHOR]