| 0893 Effect of neutralization and ultrasonic cleaning of hydrofluoric acid precipitates | ||
|
G. SAAVEDRA1, L. BUSO2, A.M.M. MESQUITA3, A.A. ALONSO4, M. BOTTINO5, and E. KIMPARA5, 1Sao Paulo State University, Brazil, 2Universidade Estadual Paulista, Sao Paulo, Brazil, 3Sao Paulo State University (Unesp/SJC), São José dos Campos, Brazil, 4Paulista State University, São José dos Campos, Brazil, 5Paulista State University, São josé dos Campos, Brazil Objectives: Evaluated three hypotheses: a) the neutralization process influences the bond strength values between a feldspar ceramic and a resin cement; b) ultrasonic cleaning of hydrofluoric acid precipitates increases the bond strength values; c) association between the neutralization process and ultrasonic cleaning improves the bond strength. Methods: thirty-two ceramic blocks of VM7 VITA were fabricated and duplicated in composite resin (W3D Master). Each ceramic block (1 aspect) was etched (20s) with 10% hydrofluoric acid followed by air-water rinsing (60s) and drying. The blocks divided into 4 groups (n=8): G1- silane was applied on the ceramic surface followed by luting to resin blocks; G2- blocks were immersed (40s) in supersaturated sodium bicarbonate solution, air-water rinsed (60s) and dried before application of silane and luting; G3- ultrasonic cleaning (4 minutes), silane and luting; G4- association of neutralization and ultrasonic cleaning. Each treated ceramic block was luted to the corresponding composite resin block with the resin cement Rely X ARC (3M). Each ceramic/cement/composite resin assembly was sectioned into two axes (X and Y) for achievement of samples and submitted to tensile testing. Results: the bond strength values and standard deviations (MPa) for the groups were as follows: G1: 19.86 ± 2.42a; G2: 15.64 ± 2.29b; G3: 23.53 ± 1.07c; G4: 29.36 ± 0.98d. The four experimental conditions presented statistically significant difference to each other (p=0.0001) (one-way ANOVA and Tukey test, p<0.05). Conclusion: the results confirmed that: a) the neutralization process influences the bond strength values between a feldspar ceramic and a resin cement; b) ultrasonic cleaning of hydrofluoric acid precipitates increases the bond strength values; c) association between the neutralization process and ultrasonic cleaning improves the bond strength | ||
| Seq #107 - Ceramics: Mechanical Properties and Marginal Fit 3:30 PM-4:45 PM, Thursday, March 22, 2007 Ernest N. Morial Convention Center Exhibit Hall I2-J | ||
![[ Poster ]](/static/img/filetypes/16x16/ppt.gif){kind=small} Poster | ||
|
Back to the Dental Materials: III - Ceramics and Cements Program
| ||