Alfordschulz4471

05). The µTBS decreased significantly with aging (5000 thermocycles) (p less then 0.05). BQ cement resulted in the highest μTBS to GR treated with TiF4 2% wt/v + CB compared to the other groups (p less then 0.05). Aged GR/BQ treated with TiF4 2% wt/v + CB had the highest predicted µTBS (19 MPa). CONCLUSION TiF4 2% wt/v followed by silane application enhanced the adhesion of GR/BQ and LU/BQ systems. On the other hand, HF surface treatment followed by silane application improved the adhesion of the VE/BQ system.PURPOSE To determine the effect of Weibull analysis with censoring of cohesive failures on the evaluation of the effect of surface treatment and adhesive on the microtensile composite-composite bond strength. MATERIALS AND METHODS Surfaces of Filtek Z250 (3M Oral Care) specimens aged in distilled water for five months at 37°C were ground with SiC paper P320 or air abraded with Al2O3 and built up with the same composite using Optibond FL (OPF, Kerr), Clearfil SE Bond (CSE, Kuraray Noritake) and Gluma Comfort Bond (GLU, Kulzer) adhesives. After sectioning and trimming, the specimens were stored at 37°C in distilled water for 24 h and then tested in a microtensile bond strength setup. Complete datasets of all strength data and adhesive datasets containing adhesively failed specimens were analyzed with a one-way Welch ANOVA at α = 0.05 and compared with the results of Weibull analysis applied on complete and adhesive datasets as well as complete datasets right censored for cohesive failures. Weibull shape (m) and ground surface for complete datasets which became statistically non-significant for the censored datasets. CONCLUSION This study indicates that the results of statistical evaluation of bond strength can be affected not only by the experimental set-up and statistical model but also the bond strength characteristics and the manner in which the strengths of cohesively failed specimens are included in calculations.PURPOSE To evaluate the influence of hydrofluoric acid (HF) concentration and etching time on the microshear bond strength (µSBS) of RelyX Unicem 2 (3M Oral Care) to VITA Suprinity (Vita Zahnfabrik; zirconia-reinforced lithium-silicate glass ceramic ZLS) and IPS e.max CAD (Ivoclar Vivadent; lithium-disilicate glass ceramic LD). MATERIALS AND METHODS Forty-eight bars each were fabricated of ZLS and LD with Cerec InLab MC-XL. For each material, 8 groups were formed with respect to etching time (20, 40, 60, 120 s) and HF concentration (4.9% and 9.5%). In each group, after etching and silanization, 15 cylindrical specimens of RelyX Unicem 2 were built up for µSBS testing with a special device. Data were analyzed using three-way ANOVA. Failure modes were assessed using an optical stereomicroscope, classified as adhesive, cohesive in resin or ceramic, or mixed. Failure modes were statistically analyzed using Fisher's Exact Test. One bar per group was prepared for SEM observation of the etched surface. RESULTS ZLS showed significantly higher bond strengths than LD (p less then 0.001). Etchant concentration was an influential factor with superior strengths after 4.9% HF etching (p = 0.009). Etching time did not significantly affect adhesion (p = 0.066). The material-etching interaction was statistically significant (p = 0.004). Particularly for ZLS, 4.9% HF etching obtained significantly higher bond strengths than did 9.5%. By using 4.9% HF, adhesion was significantly higher on ZLS than on LD. CONCLUSION Material and HF concentration influenced the adhesion between RelyX Unicem 2 composite cement and lithium-silicate glass ceramics. Etching time was not an influential factor. The use of 4.9% HF for 20 s proved to be the most effective etching treatment of the intaglio surface.PURPOSE To evaluate 1. the microtensile bond strength (µTBS) and in situ degree of conversion (DC) of adhesives applied using two bonding strategies after silver diamine fluoride (diamine) application on carious dentinal lesions, and 2. dentin etching patterns using SEM and energy dispersive x-ray spectroscopy. MATERIALS AND METHODS Human molars were randomly divided into 12 experimental groups according to 1. application of a silver diamine fluoride solution (carious dentinal lesion without silver diamine fluoride treatment [control], with 12% silver diamine fluoride [diamine 12%] or 38% silver diamine fluoride [diamine 38%]); 2. adhesives (Clearfil Universal Bond Quick [CUQ] and Scotchbond Universal [SBU]); 3. adhesive strategy (etch-and-rinse [ER] and self-etch [SE]). After restoration, the specimens were sectioned and submitted to µTBS testing. Sticks from each tooth were used for DC evaluation. To examine the changes induced by diamine before and after phosphoric acid treatment, SEM/EDX analysis was performed. Data from the µTBS and DC tests were analyzed using three-way ANOVA and Tukey's test (α = 0.05). RESULTS Both concentrations of diamine resulted in a statistically significantly higher mean µTBS compared to the control (p less then 0.0001). selleck products Diamine 38% showed a statistically significantly higher mean µTBS for both adhesives in SE mode compared to diamine 12% (p less then 0.0001). The application of diamine to carious dentinal lesions did not significantly influence the mean DC values for either adhesive (p = 0.72). SBU showed a higher mean DC compared to CUQ (p = 0.03). After diamine treatment, there was an increase in the Ca peak intensity and the presence of residual silver ions mainly when diamine 38% was applied along with the SE approach. CONCLUSION Independent of the adhesive application approach, the use of diamine may be a promising alternative to increase µTBS without jeopardizing the DC of the two adhesives in carious dentinal lesions.PURPOSE To evaluate the influence of new air-abrasion powders with different silica concentrations (silica-coated aluminum oxide) and aging on the bond strength between composite cement and Y-TZP ceramic. MATERIALS AND METHODS Ceramic slices (7 x 6.3 x 2 mm3) were randomly allocated into 8 groups (n = 20) considering different surface treatments (SiC silica-coated aluminum oxide particles; AlOx aluminum oxide particles; 7% Si and 20% Si experimental powders consisting of 7% and 20% silica-coated of AlOx respectively) and aging (baseline 24 h at 37°C in water; aged 90 days at 37°C in water + 12,000 thermal cycles). A blinded researcher performed the air-abrasion procedure for 10 s (identical parameters for all groups). Composite resin cylinders (Ø = 3 mm) were cemented onto the silanized ceramic surfaces, light cured, and subjected to shear bond-strength testing (wire loop Ø = 0.5 mm). The topography of the powders and air-abraded surfaces was analyzed using SEM and atomic force microscopy (AFM). The elemental composition of the powders and air-abraded surfaces was analyzed with energy dispersive spectroscopy (EDS), and surface wetting of the air-abraded surfaces was also determined by contact-angle measurements.