Influence of ceramic pre-treatments on tensile bond strength and mode of failure of resin bonded to ceramics.
OBJECTIVE
To evaluate the effect of ceramic surface treatments on tensile bond strength (sigma) and the mode of failure of a resin bonded to a feldspathic glass and a low-crystalline ceramic, testing the hypothesis that a silica coating treatment is unnecessary for both the glass and the low-crystalline ceramic.


METHODS
10 blocks of each the feldspathic glass (V7-VITAVM7) and the leucite-based ceramic (E1-IPS Empress) were fabricated and polished. Five blocks of each ceramic were treated as follows: 9.5% hydrofluoric acid for 60 seconds; and silica coating using Cojet System for 15 seconds. After silane coating, an adhesive resin and a composite were applied and polymerized. The composite-ceramic blocks were cut to produce bar-shaped specimens (n = 30) that were stored in distilled water at 37 degrees C for 7 days before tensile loading to failure in a universal testing machine. Data were statistically analyzed using analysis of variance, Tukey's test (alpha = .01) and Weibull analysis. Fracture surfaces were examined to determine the mode of failure.


RESULTS
The Weibull modulus (m) and mean sigma value (MPa) of Group E1HF (29.8 +/- 4.5) were significantly higher than other Groups (P = .0001). There was no statistical difference between Groups E1CS (24.6 +/- 5.6) and V7HF (22.3 +/- 4.0). Group V7CS showed the lowest m and mean sigma values (15.7 +/- 6.9) (P = .0001). All fractures occurred within the adhesion zone.
Boscato
Noéli
N
Department of Prosthodontics, School of Dentistry, State University of Campinas, Piracicba, São Paulo, Brazil.
Della Bona
Alvaro
A
Del Bel Cury
Altair Antoninha
AA
D000538:Aluminum Silicates / Q000737:chemistry*; D000704:Analysis of Variance; D003722:Dental Alloys / Q000737:chemistry*; D001840:Dental Bonding / Q000379:methods*; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry*; D013499:Surface Properties; D013718:Tensile Strength
D000538:Aluminum Silicates; D003722:Dental Alloys; D003764:Dental Materials; C075815:IPS-Empress ceramic; D003776:Dental Porcelain; C047040:Vita VMK 68