![]() ![]() Airborne-particle-abraded specimens bonded with either Panavia F 2.0, RelyX ARC, or Bistite II DC resulted in a mean (SD) bond strength of 23.3 (2.4), 33.4 (2.1), 31.3 (2.8) MPa, respectively, while the highest bond strength of 49.8 (2.7) MPa was achieved for the selective infiltration-etched specimens bonded with Panavia F 2.0. There were significant differences in the initial MTBS values (MPa) between the 4 bonding techniques (P<.001). Pairwise comparisons were made using the Bonferroni post hoc test. A repeated measures ANOVA with 1 within-subjects factor (time, 5 levels) and 1 between-subjects factor (technique, 4 levels) was used to analyze the data (alpha=.05). The density (g/cm(3)) and the 4-point flexure strength (MPa) of the selective infiltration-etched and airborne-particle-abraded specimens were measured to evaluate the effect of selective infiltration etching on the structural integrity of the Y-TZP specimens. Scanning electron microscopy was used to examine the fractured microbars. The bonded specimens were cut into microbars (6 x 1 x 1 mm), and a microtensile bond strength test (MTBS measured in MPa) was conducted immediately, after 1 week, 2 weeks, 3 weeks, and after 1 month of water storage (5 microbars/disc/time interval/group, n = 450 microbars/group). Panavia was used to bond the selective infiltration-etched specimens. Three commercial adhesive systems (Panavia F 2.0, RelyX ARC, and Bistite II DC) were used to bond the airborne-particle-abraded zirconia specimens to preaged restorative composite resin discs (Filtek Z250). One test group received the selective infiltration-etching surface treatment. Seventy-two Y-TZP discs (19.5 x 3 mm) were airborne-particle abraded with 110-mum aluminum oxide particles and divided into 4 groups (n=18). The purpose of this study was to evaluate the zirconia-resin bond strength and durability using a selective infiltration-etching technique. The two-year recall examination showed that sealant, repair and refurbishing treatments improved the clinical properties of defective amalgam and resin-based composite restorations by increasing the longevity of the restorations with minimal intervention.Įstablishing a strong and a stable adhesive bond between yttrium, partially stabilized, tetragonal zirconia, polycrystal materials (Y-TZP) and resin luting agents has proven to be difficult using conventional surface roughening and coating methods. The Untreated group showed significant deterioration on marginal adaptation (p < 0.013). Replacement showed significant improvements for all parameters (p < 0.05). The repair significantly improved anatomic form (p < 0.002) and marginal stain (p < 0.002). Refurbishing of the defective restorations significantly improved anatomic form (p < 0.0001), luster (p < 0.016), marginal adaptation (p < 0.003) and roughness (p < 0.0001). The sealing of marginal defects showed significant improvements in marginal adaptation (p < 0.05). Two-hundred and fifty-six restorations (178 amalgam and 78 resin-based composite) were examined at the two-year recall exam. Two calibrated examiners (Cohen's Kappa 0.74) assessed the restorations independently at the beginning of the study (baseline) and at two years after treatment using seven parameters from the USPHS/Ryge criteria (Marginal Adaptation, Anatomic Form, Roughness, Marginal Stain, Occlusal Contact, Secondary Caries and Luster). USPHS/Ryge criteria were used to determine the quality of the restorations. Sixty-six patients (age 18 to 80 years, mean = 26.6) with 271 (amalgam and resin-based composite ) defective restorations were randomly assigned to one of five different treatment groups: A) Repair (n = 27) B) Sealing of margins (n = 48) C) Refurbishing (n = 73) D) Replacement (n = 42) and E) Untreated (n = 81). This investigation assessed the effectiveness of alternative treatments for the replacement of amalgam and resin-based composite restorations.
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