ABSTRACT
The objective of this study was to evaluate the influence of different primers on the microtensile bond strength (µTBS) between a feldspathic ceramic and two composites. Forty blocks (6.0 x 6.0 x 5.0 mm³) were prepared from Vita Mark II . After polishing, they were randomly divided into 10 groups according to the surface treatment: Group 1, hydrofluoric acid 10% (HF) + silane; Group 2, CoJet + silane; Group 3, HF + Metal/Zirconia Primer; Group 4, HF + Clearfil Primer; Group 5, HF + Alloy Primer; Group 6, HF + V-Primer; Group 7, Metal/Zirconia Primer; Group 8, Clearfil Primer; Group 9, Alloy Primer; Group 10, V-Primer. After each surface treatment, an adhesive was applied and one of two composite resins was incrementally built up. The sticks obtained from each block (bonded area: 1.0 mm² ± 0.2 mm) were stored in distilled water at 37 degrees C for 30 days and submitted to thermocycling (7,000 cycles; 5 degrees C/55 degrees C ± 1 degree C). The µTBS test was carried out using a universal testing machine (1.0 mm/min). Data were analyzed using ANOVA and a Tukey test (a = 0.05). The surface treatments significantly affected the results (P < 0.05); no difference was observed between the composites (P > 0.05). The bond strength means (MPa) were as follows: Group 1a = 29.6; Group 1b = 33.7; Group 2a = 28.9; Group 2b = 27.1; Group 3a = 13.8; Group 3b = 14.9; Group 4a = 18.6; Group 4b = 19.4; Group 5a = 15.3; Group 5b = 16.5; Group 6a = 11; Group 6b = 18; Groups 7a to 10b = 0. While the use of primers alone was not sufficient for adequate bond strengths to feldspathic ceramic, HF etching followed by any silane delivered higher bond strength.
Subject(s)
Acid Etching, Dental/methods , Ceramics/chemistry , Dental Materials/chemistry , Aluminum Silicates/chemistry , Composite Resins/chemistry , Dental Bonding , Dental Polishing/methods , Dental Porcelain/chemistry , Dental Prosthesis Repair , Dental Stress Analysis/instrumentation , Humans , Hydrofluoric Acid/chemistry , Materials Testing , Methacrylates/chemistry , Microscopy, Electron, Scanning , Potassium Compounds/chemistry , Resin Cements/chemistry , Silanes/chemistry , Stress, Mechanical , Surface Properties , Temperature , Tensile Strength , Thiones/chemistry , Time Factors , Triazines/chemistry , Water/chemistryABSTRACT
El objetivo de este estudio fue evaluar y comparar la adaptación marginal de restauraciones, confeccionadas con dos tipos de sistemas cerámicos: CEREC® inLab (VITA) e IPS Empress 2(Ivoclar-Vivadent), después de su cementación con cemento resinoso. Fueron tallados 20 premolares humanos con cavidad MOD inlay, reproducidos con silicona de adición, y obtenidos modelos en yeso tipo IV, sobre los cuales fueron confeccionados las restauraciones conforme alas recomendaciones de los fabricantes. Diez inlays con el sistema IPS Empress 2 y 10 inlays con el sistema CEREC® inLab. Las restauraciones fueron cementadas bajo presión constante de 1,5 Kgf por 10 min, con cemento resinoso. Las desadaptaciones marginales fueron evaluadas conMEB, con magnificación de 200x, en 50 puntos equidistantes. Las medias fueron analizadas por el método estadístico t de Student de muestras dependientes. Resultando en una diferencia estadísticamente significante entre las desadaptaciones marginales en el sistema IPS Empress (93,8 15,5μm), que se mostraron menores que en el sistema CEREC® inLab (114,4±10,6μm).Cuando se compararon las medias entre las caras proximales (116,51±21,85μm) y Oclusal(112,26±8,49μm) del sistema CEREC®InLab, y las caras proximales (87,12±27,98μm) y Oclusal(100,47±22,23μm) del sistema IPS Empress 2, se verificó que esos valores no difieren estadísticamente. En frente a esos resultados se concluyó que las medias obtenidas son aceptables clínicamente.
This study has the purpose to evaluate the marginal adaptation of two system of all-ceramic class II inlays: one of laboratory-made heat-pressed ceramics (IPS Empress 2) and the othercomputer-aided manufacturing (CEREC®inLab) after cementation with resin cement . Extracted human premolars were prepared to receive mesio occluso distal (MOD) ceramic inlays for 10 IPS Empress restorations and 10 CEREC®inLab restorations. The impression material used was a polivinilsyloxane addition silicone by the double impression technique. The impressions of prepared teeth were cast in type IV dental stone. The restorations were made following the manufacturer's recommendations. The inlays were luted on human premolars with resin cementin accordance with the manufacturer's recommended pre-treatment. The marginal gaps were investigated by scanning electron microscopy with magnification of 200X. The results wereanalyzed by t(Student) statistic test. The means marginal gap for IPS Empress 2 was 93.8±15.5μmsignificantly lower than 114.4±10.6μm calculated at the CEREC®inLab system. The gaps of the inlays at the occlusal margin and of the approximal margin showed no significantly differencesin two systems. It may be concluded that measurement value are clinically acceptable.
