The effect of different surface treatments on bond strength between leucite reinforced feldspathic ceramic and composite resin.
OBJECTIVE
The aim of this study was to evaluate the effect of different surface treatments on the microtensile bond strength between a leucite reinforced glass-ceramic and composite resin.


METHODS
Leucite reinforced ceramic blocks (n=24) were constructed using the hot pressing technique. The blocks were assigned to 4 groups, which received the following surface treatments: G1: hydrofluoric (HF) acid and silane; G2: silane alone; G3: HF acid and silane then dried with warm air (100 degrees C); G4: silane alone then dried with warm air (100 degrees C). Unfilled resin was applied, followed by composite resin. Specimens were prepared and loaded in tension to determine the microtensile bond strength. Failure modes were classified by stereo- and scanning electron microscopy (SEM). Data was analysed using Kruskal-Wallis test followed by the Dunn's multiple range test.


RESULTS
The groups including the warm air step (G3 and G4) achieved a significantly stronger adhesion than G1 and G2. Pre-treatment of the surface with hydrofluoric acid in G1 resulted in significantly higher bond strength than G2. Failures were mostly cohesive in the luting resin for G1, G3 and G4 and mainly adhesive at the ceramic-resin interface in G2.


CONCLUSIONS
The method of application of silane to the ceramic surface can have a significant influence on the adhesion between the ceramic restoration and the resin cement. Enhancing the condensation reaction by drying the silane with a 100C warm air stream significantly improved the microtensile bond strength, possibly eliminating the need for the hydrofluoric acid etching step.
Fabianelli
Andrea
A
Department of Dental Materials, University of Siena, Italy.
Pollington
Sarah
S
Papacchini
Federica
F
Goracci
Cecilia
C
Cantoro
Amerigo
A
Ferrari
Marco
M
van Noort
Richard
R
D000134:Acid Etching, Dental / Q000379:methods; D000388:Air; D000538:Aluminum Silicates / Q000737:chemistry*; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D017554:Carbon Compounds, Inorganic / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D006358:Hot Temperature; D006801:Humans; D006858:Hydrofluoric Acid / Q000737:chemistry; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D011140:Polyurethanes / Q000737:chemistry; D017680:Potassium Compounds / Q000737:chemistry*; D012821:Silanes / Q000737:chemistry; D017655:Silicon Compounds / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength
D000538:Aluminum Silicates; D017554:Carbon Compounds, Inorganic; D003188:Composite Resins; D003738:Dental Cements; D003764:Dental Materials; C075815:IPS-Empress ceramic; D008689:Methacrylates; C076808:Monobond S; D011140:Polyurethanes; D017680:Potassium Compounds; D012821:Silanes; D017655:Silicon Compounds; C501891:Tetric EvoCeram; D003776:Dental Porcelain; C016447:feldspar; C029824:urethane dimethacrylate luting resin; C078519:leucite; D017438:Bisphenol A-Glycidyl Methacrylate; C005044:hydroxyethyl methacrylate; C023506:Glass ceramics; D006858:Hydrofluoric Acid; C022088:silicon carbide