Microtensile bond strength of a resin cement to feldpathic ceramic after different etching and silanization regimens in dry and aged conditions

Brentel, Aline Scalone; Özcan, Mutlu; Valandro, Luiz Felipe; Alarça, Lilian Guimarães; Amaral, Regina; Bottino, Marco Antonio

doi:10.1016/j.dental.2006.11.011

« Previous Next »Dental Materials
Volume 23, Issue 11 , Pages 1323-1331, November 2007

Microtensile bond strength of a resin cement to feldpathic ceramic after different etching and silanization regimens in dry and aged conditions

Aline Scalone Brentel
- São Paulo State University, Department of Dental Materials and Prosthodontics, São José dos Campos, Brazil
Mutlu Özcan
- University Medical Center Groningen, University of Groningen, Department of Dentistry and Dental Hygiene, Clinical Dental Biomaterials, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
- Corresponding author. Tel.: +31 50 363 8528; fax: +31 50 363 2696.
Luiz Felipe Valandro
- São Paulo State University, Department of Dental Materials and Prosthodontics, São José dos Campos, Brazil
- Federal University of Santa Maria, Department of Restorative and Prosthetic Dentistry, Santa Maria, Brazil
Lilian Guimarães Alarça
- São Paulo State University, Department of Dental Materials and Prosthodontics, São José dos Campos, Brazil
Regina Amaral
- São Paulo State University, Department of Dental Materials and Prosthodontics, São José dos Campos, Brazil
Marco Antonio Bottino
- São Paulo State University, Department of Dental Materials and Prosthodontics, São José dos Campos, Brazil

Received 19 July 2006; accepted 16 November 2006.

Abstract

Objectives

This study evaluated the durability of bond strength between resin cement and a feldspathic ceramic submitted to different etching regimens with and without silane coupling agent application.

Methods

Thirty-two blocks (6.4mm×6.4mm×4.8mm) were fabricated using a microparticulate feldspathic ceramic (Vita VM7), ultrasonically cleaned with water for 5min and randomly divided into four groups, according to the type of etching agent and silanization method: method 1, etching with 10% hydrofluoric (HF) acid gel for 1min+silanization; method 2, HF only; method 3, etching with 1.23% acidulated phosphate fluoride (APF) for 5min+silanization; method 4, APF only. Conditioned blocks were positioned in their individual silicone molds and resin cement (Panavia F) was applied on the treated surfaces. Specimens were stored in distilled water (37°C) for 24h prior to sectioning. After sectioning the ceramic-cement blocks in x- and y-axis with a bonded area of approximately 0.6mm², the microsticks of each block were randomly divided into two storage conditions: Dry, immediate testing; TC, thermal cycling (12,000 times)+water storage for 150d, yielding to eight experimental groups. Microtensile bond strength tests were performed in universal testing machine (cross-head speed: 1mm/min) and failure types were noted. Data obtained (MPa) were analyzed with three-way ANOVA and Tukey's test (α=0.05).

Results

Significant influence of the use of silane (p<0.0001), storage conditions (p=0.0013) and surface treatment were observed (p=0.0014). The highest bond strengths were achieved in both dry and thermocycled conditions when the ceramics were etched with HF acid gel and silanized (17.4±5.8 and 17.4±4.8MPa, respectively). Silanization after HF acid gel and APF treatment increased the results dramatically (14.5±4.2–17.4±4.8MPa) compared to non-silanized groups (2.6±0.8–8.9±3.1MPa) where the failure type was exclusively (100%) adhesive between the cement and the ceramic.

Significance

Silanization of the feldspathic ceramic surface after APF or HF acid etching increased the microtensile bond strength results significantly, with the latter providing higher results. Long-term thermocycling and water storage did not decrease the results in silanized groups.

Keywords: Acidulated phosphate fluoride, Etching, Hydrofluoric acid, Microtensile bond strength, Feldspathic ceramic, Silane coupling agent