Objective: Compare in vitro diametral tensile strength of two Bulk Fill Aura® (SDI) and Tetric-N-Ceram® type resins subjected to two Red Bull® and Volt energy drinks. Materials and methods: The study was experimental in vitro. 132 Bulk Fill type resin bodies were evaluated, which were divided into six groups of 22 resin bodies each. Groups 1, 2 and 3 were made with Aura® resin (SDI) and groups 4, 5 and 6 with Tetric-N-Ceram® resin. Groups 1 and 4 were submerged in the Red Bull® energy drink and groups 2 and 5 in the Volt energy drink for 10 min / 1 time a day for 7 days. On the other hand, groups 3 and 6 were control groups, only immersed in distilled water for 7 days. The diametral tensile strength was evaluated through the Instron® universal test machine (speed 0.5mm / min - load 100 KN), measured in MPa. To evaluate the results of each of the variables and perform the univariate analysis, we proceeded to obtain measures of central tendency and measures of dispersion. To evaluate the bivariate analysis, the Kruskal Wallis test was carried out. Results: The control group of the Aura® resin presented a mean and a S.D of 46.51 + 3.14, while the control group of the Tetric-N-Ceram® resin presented 46.04 + 3.22. It was found that the Aura® resin when submerged in Red Bull® presented an average and a S.D of 35.58 + 7.63, while when submerged in Volt, it presented 35.24 + 5.13. On the other hand, the Tetric-N-Ceram® resin after being submerged in the Red Bull® presented a mean and a S.D of 37.46 + 6.18, while when submerged in Volt it presented 36.15 + 6.74. Conclusions: There are no statistically significant differences when evaluating the resistance to the diametral tension strength of the Bulk Fill type resins, submitted to the Red Bull® energy drink (p = 0.796), or to Volt (p = 0.496).

Objetivo: Comparar in vitro la resistencia a la compresión y resistencia flexural de resinas Bulk Fill (Opus™ Bulk Fill, Tetric® N-Ceram Bulk Fill y Filtek™ Bulk Fill) Materiales y métodos: Se confeccionaron 132 especímenes en total: G1/G5: Opus™ Bulk Fill, G2/G6: Tetric® N-Ceram Bulk Fill, G3/G7: FiltekTM Bulk Fill y G4/G8: FiltekTM Z350XT (grupo control). Cincuenta y seis especímenes cilíndricos (3x5mm) para evaluar la resistencia a la compresión, divididos en 4 grupos (n=14): G1, G2, G3 y G4 y setenta y seis especímenes rectangulares para evaluar la resistencia flexural, divididos en 4 grupos (n=19): G5, G6, G7 y G8. Las pruebas mecánicas se realizaron en una máquina de ensayo universal Instron® con una carga de 100kN a 1mm/1min (Resistencia Compresiva) y una velocidad de 1mm/1min (Resistencia Flexural). El análisis de datos se realizó mediante estadística descriptiva e inferencial (test de Kruskal Wallis /prueba post hoc). Resultados: Para la resistencia a la compresión, los resultados fueron: G1 (141.68 MPa ± 22.20), G2 (139.03 MPa ± 23.56), G3 (235.59 MPa ± 26.08) y G4 (99.28 MPa±11.36). Se encontró diferencias estadísticamente significativas entre todas las resinas evaluadas (p<0.001). Para resistencia flexural los resultados fueron: G5 (116.29 MPa ± 7.20), G6 (109.67 MPa ± 7.58), G7 (200.53 MPa ± 10.32) y G8 (90.08 MPa ± 8.63). Se encontró diferencias estadísticamente significativas entre todas las resinas evaluada (p<0.001). Conclusiones: La resina Filtek™ Bulk Fill presentó mayor resistencia a la compresión y flexural en relación a las resinas evaluadas.

Objective: The purpose of this study, in vitro, was to compare the surface microhardness of two Bulk Fill resins immersed in energizing beverages. Materials and Methods: A total of 60 resin blocks divided into two groups (n = 30) were used according to each brand of Tetric® N-Ceram Bulk Fill (TNC) and Aura Bulk Fill (Aura) resin, which in turn were divided into Two subgroups (15 resin samples per Red Bull® and Volt®: G1: TNC + Red Bull®, G2: TNC + Volt®, G3: Aura + Red Bull®, G4: Aura + Volt® energizing drink. The microhardness before and after being inmersed to the action of the energizing drinks by the erosive challenge performed in 40 ml of each energizing drink / 15 test bodies of each group (10 minutes + 1 time day / 5 days). Data was analyzed with Student's t-test. Results: The initial and final microhardness values were obtained: G1 74.46 kg / mm2 + - 5.98 / 60.33 kg / mm2 + - 6.95, G2 74.8 kg / mm2 + - 6.15 / 60.4 kg / mm2 + - 7.05, G3 57 kg / Mm2 + - 8.41 / 42 kg / mm2 + - 8.82, G4 53.13 kg / mm2 + - 6.66 / 41.73 kg / mm2 + - 8.14. When comparing the erosive effect of both energizing drinks, these did not present significant differences for the Tetric N-Ceram Bulk Fill resin (p = 0.59). However, the Aura Bulk Fill inmersed in Volt had significant differences (p = 0.022), showing that this beverage presented greater erosive effect than the Red Bull beverage. Conclusion: When comparing the surface microhardness of both resins before and after the in vitro erosive challenge of the energizing drinks, the Tetric N-Ceram Bulk Fill resin presented a smaller reduction of superficial microhardness in comparison to the resin Aura Bulk Fill.

Objetivo: Comparar la microdureza y rugosidad superficial in vitro en resinas Bulk Fill después de un desafío abrasivo con pasta blanqueadora. Materiales y métodos: Noventa especímenes de resinas Bulk Fill Filtek™ Bulk Fill (FB), Tetric® N-Ceram Bulk Fill (TNC), Opus Bulk Fill (OBF) fueron divididos en 6 grupos (n=15). El desafío abrasivo in vitro fue realizado con un cepillo eléctrico Oral B y una solución de 3,3 ml de pasta dental / agua destilada por 30 s. La microdureza y rugosidad superficial inicial y final fue evaluada a los 15 y 30 días. Los datos fueron analizados mediante estadística descriptiva e inferencial (U Mann Whitney) Resultados: La rugosidad superficial a los 15 días fue: FB (0.09± 0.03µm/0.17± 0.10 µm); TNC (0.16 ± 0.09 µm/0.20± 0.09µm) y OBF (0.13±0.09 µm/0.18±0.06 µm). A los 30 días fue: FB (0.10 ± 0.05 µm/0.12 ±0.06 µm); TNC (0.07±0.04 µm/0.16±0.07µm) y OBF (0.11±0.03 µm/0.22±0.12 µm). Hubo diferencias estadísticamente significativas para FB (p=0.003) y OBF (p=0.0008) a los 15 días. A los 30 días, las resinas que presentaron un aumento significativo en los valores de rugosidad fueron OBF (p<0.0001) y TNC (p=0.0011). En la microdureza superficial, a los 15 días fue: FB (63.49±15.10 kg/mm2 / 65.53±8.21kg/mm2); TNC (47.67±6.20 kg/mm2 / 46.67±6.43 kg/mm2) y OBF (47.33±4.57 kg/mm2 / 45.4±4.32 kg/mm2). Existe una disminución a los 15 días en la resina OBF (p=0.0001). Conclusiones: Existe un aumento en la rugosidad superficial de las resinas Bulk Fill a los 15 y 30 días. Hubo una disminución en la microdureza superficial para la resina Opus Bulk Fill a los 15 días. Aim: To compare in vitro the microhardness and surface roughness in Bulk Fill composites after an abrasive challenge with whitening toothpaste. Materials and methods: Ninety specimens of Bulk Fill Filtek ™ Bulk Fill (FB), Tetric® N-Ceram Bulk Fill (TNC), Opus Bulk Fill (OBF) composite were divided into 6 groups (n = 15).The in vitro abrasive challenge was performed with an Oral B electric toothbrush and a 3,3 ml solution of toothpaste / distilled water for 30 s. The microhardness and initial and final surface roughness was evaluated at 15 and 30 days. The data were analyzed by descriptive and inferential statistics ¬(Mann Whitney U Test). Results: The surface roughness at 15 days was: FB (0.09 ± 0.03μm / 0.17 ± 0.10 μm); TNC (0.16 ± 0.09 μm / 0.20 ± 0.09μm) and OBF (0.13 ± 0.09 μm / 0.18 ± 0.06 μm). At 30 days it was: FB (0.10 ± 0.05 μm / 0.12 ± 0.06 μm); TNC (0.07 ± 0.04 μm / 0.16 ± 0.07μm) and OBF (0.11 ± 0.03 μm / 0.22 ± 0.12 μm). There were statistically significant differences for FB (p = 0.003) and OBF (p = 0.0008) at 15 days. After 30 days, the Bulk Fill composite that showed significant increases in the roughness values were OBF (p <0.0001) and TNC (p = 0.0011). The surface microhardness at 15 days was: FB (63.49 ± 15.10 kg / mm2 / 65.53 ± 8.21kg / mm2); TNC (47.67 ± 6.20 kg / mm2 / 46.67 ± 6.43 kg / mm2) and OBF (47.33 ± 4.57 kg / mm2 / 45.4 ± 4.32 kg / mm2). There was a decrease after 15 days in the OBF composite (p = 0.0001). Conclusions: There was an increase in the surface roughness of Bulk Fill composite at 15 and 30 days. There was a decrease in surface microhardness for the Opus Bulk Fill composite after 15 days.

Objective: To compare in vitro the conversion degree of the Tetric N-Ceram®, SonicFill™ and control resin Filtek ™ Z350 XT. Materials and Methods: 90 plastic matrix of 4x5mm were confectioned and divided on 3 groups of 30 for each evaluated resin brand and subdivided in 10 samples for each evaluated depth (superficial, middle and bottom). The material was insert according each maker indications in an incremental 2mm or unique 4mm way and photopolymerized with a light font (LEDition – Ivoclar Vivadent) with 810 mw/cm2. The values were evaluated by moving the absorbance (A) results obtained in a Fourier Transform Infrared Spectroscopy (FTIR) with an Attenuated Total Reflactance unit (ATR) to an equation that allowed obtaining the CD in percents (%). Results: There were statistically significant differences found between the values of conversion degree of the different resins brands that were evaluated. CD values on surface, middle and bottom of the samples for Tetric N-Ceram® resin were 96.76 + 0.69, 75.09 + 0.51 and 44.30 + 0.80; 96.76 + 0.69, for SonicFill™ were 96.53 + 0.59, 77.45 + 0.92 and 58.64 + 0.59; and for Filtek ™ Z350 XT were 88.69 + 0.78, 80.61 + 1.90 and 65.56 + 1.01 respectively. Conclusions: It was found that CD of Bulk Fill resins was decreasing as the depth increased caused by more material quantity needs a higher penetration of the LED light.

Objective: Comparison in vitro the superficial roughness of two Bulk Fill resins using two polishing systems of abrasives rubbers: JOTA® (Switzerland) (aluminum oxide, silicium carbide and silicone) and Optimize® (TDV) (Germany) (silicone- aluminum oxide). Materials and methods: Were used 60 resin specimens of resin divided in four groups G1: Tetric-N Ceram® Bulk Fill (Ivoclar Vivadent, USA)/ polishing system JOTA®( Switzerland), G2: Tetric-N Ceram® Bulk Fill (Ivoclar Vivadent, USA)/polishing system Optimize® (TDV) (Germany), G3: Aura Bulk Fill (SDI, Brazil) / polishing system JOTA® (Switzerland) y G4: Aura Bulk Fill (SDI, Brazil) / polishing system Optimize® (TDV) (Germany). All the specimens were made in a metal matrix (6mm x 4mm), were the resins were inserted with a resin spatula (TNCIGFT2 Hu Friedy), and fotoactivated with a lamp Elipar LedTM (3M-ESPE), with an intensity of 1200 mW/cm2. Immediately, the initial roughness of all groups is measured with the Roughness meter Mitutoyo SJ-210P (China). Subsequently, the polishing was executed out with the two rubber systems according to each group, and the final roughness was measured. Results: Statistically significant difference was found on the roughness of G1. This is even greater than all the groups evaluated, and that the smallest difference was in the G2 group. A statistically significant difference was found when comparing the two resins with the polishing systems evaluated. Conclusions: The surface roughness found in the evaluation of Bulk Fill Tetric-N Ceram® Bulk Fill (Ivoclar Vivadent, USA), with the JOTA® (Switzerland) polishing system presents the lower roughness than Aura Bulk Fill resin (SDI, Brazil) with the two polishing systems evaluated.

Objective: To compare the adhesive resistance between brackets cemented with Rely a Bond and Orthocem in bovine teeth bleached with hydrogen peroxide at 35% at different time intervals (24 hours, 7 days and 14 days). Materials and Methods: We used 72 bovine incisors divided in 6 groups (n=12): For groups 1, 2 and 3, brackets were cemented with Rely a Bond at 24 hours, 7 days and 14 days after tooth bleaching, respectively. For groups 4, 5 and 6, brackets were cemented with Orthocem at the same respective times. Samples were stored in normal saline at 0.09% at 37C° until they were evaluated. Shear test was used at crosshead speed of 1 mm/min and the adhesive remnant index (ARI) was registered using a digital microscope (Dino-Lite – China). Data was analyzed and compared with the Kruskall Wallis test (p<0.05). Results: No statistically significant differences were found through time in both cements (p=0.622 and 0.227). Comparison between both cements was statistically significant at 7 and 14 days (p=0.046 and 0.049). Conclusions: The Orthocem orthodontic cement has greater adhesive resistance and that cementation time after bleaching impacts the adhesion of the bracket.

Objective: The aim of this study was compare the compressive strength of 2 Bulk fill resin composites and 2 conventional resin composites. Materials and methods: one hundred and thirty six cylindrical samples (2mm and 4mm), divided in 8 groups (n = 17); G1 SonicFill™ (4x2mm), G2 SonicFill™ (4x4mm), G3 Tetric® N-Ceram Bulk Fill (4x2mm), G4 Tetric® N-Ceram Bulk Fill (4x4mm), G5 Filtek™ Z250 XT (4x2mm), G6 Filtek™ Z250 XT (4x4mm), G7 Te-Econom Plus® (4x2mm) and G8 Te-Econom Plus® (4x4mm). Specimens were evaluated to compressive stress test using Instron® machine at crosshead speed of 1.0 mm/min. One way Anova, Kruskall Wallis, Student's t and U Mann Whitney tests were employed for statistical analyses. Results: For Bulk resin composites, Tetric® N-Ceram Bulk Fill (310.06-4x2mm, 303.87-4x4mm) showed higher compressive strength than SonicFill™. For conventional resin composites, Filtek™ Z250 XT (295.9-4x2mm, 289.7-4x4mm) showed higher compressive strength than Te-Econom Plus®. For comparison,Tetric® N-Ceram Bulk Fill was higher compressive strength in both thickness 4x2mm (p=0.122) and 4x4mm (p=0.333) and it was statistically significant (<0.001*-4x2mm, 0.004-4x4mm) among them. Conclusion: Tetric® N-Ceram Bulk Fill offers a good mechanical property like a compressive strength which is better in comparison to the others resin composites evaluated in this study.

Objetivo: comparar in vitro la microdureza superficial de la resina Tetric® N-Ceram Bulk Fill y la resina SonicFill™, según profundidad de fotocurado. Materiales y métodos: el estudio fue experimental in vitro. Se realizaron 32 cuerpos de prueba divididos en 4 grupos: Tetric® N-Ceram Bulk Fill a 2mm de espesor, Tetric® N-Ceram Bulk Fill a 4mm de espesor, SonicFill™ a 2mm de espesor, SonicFill™ a 4mm de espesor. Se prepararon en matrices metálicas de 6x2x4 mm de espesor, los cuales fueron irradiados desde la superficie más superficial. Todos los especímenes se almacenaron en una estufa a 37◦C durante 24 horas, antes de la medición. La dureza Vickers se midió en función al espesor del material por la superficie superior e inferior del cuerpo de prueba, de los cuatro grupos antes mencionados. Los datos se analizaron con las pruebas de Shapiro Wilk y t de Student. Resultados: la resina SonicFill™ a los 2 y 4mm de espesor tuvo mayor microdureza superficial con una media de74.75+3.38kg/mm2 y 72.65+1.93kg/mm2 respectivamente a comparación de la resina Tetric® N-Ceram Bulk Fill. Por otro lado la microdureza superficial de la resina Tetric® N-Ceram Bulk Fill y SonicFill™en la superficie superior es mayor con una media de 60.87+2.53kg/mm2 y 74.75+3.38kg/mm2 que en la superficie inferior con una media de 51.25+1.95kg/mm2 y 71.37+2.68 kg/mm2. Conclusiones: se encontraron diferencias estadísticamente significativas al comparar las resinas Tetric® N-Ceram Bulk Fill y SonicFill™ a los 2mm y 4mm de profundidad, con mayor microdureza superficial en la resina SonicFill™a los 2mm y 4mm de profundidad en la superficie superior.

Objetivo: Comparar in vitro la microdureza superficial de dos resinas compuestas (Filtek™ Z 350xt y Tetric® N-Ceram) sumergidas en una bebida isotónica (Gatorade®) y una bebida energizante (Red Bull®). Materiales y métodos: El estudio fue experimental in vitro. Se confeccionaron 44 bloques de resina compuesta, los cuales se dividieron en dos grupos según marca y, dentro de estos, según tipo de bebida isotónica y energizante para lo que se utilizó 11 especímenes para la bebida Gatorade® y Red Bull®. Los bloques de resina estuvieron almacenados en agua destilada en una estufa a 37° C. Se midió la microdureza inicial a las 24 horas de confeccionadas las muestras. Posteriormente, se sumergieron en las bebidas isotónicas por 10 minutos diarios durante 5 días y luego se procedió a medir la microdureza final a través del microdurómetro de Vickers. Resultados: Se encontró una media inicial de 77.73 + 4.34 y de 73.73+ 3.93, y una media final de 54.27 + 4.29 y 52.64+ 3.59 para la resina Tetric® N-Ceram luego de ser sumergida a la bebida Red Bull® y Gatorade® respectivamente. Asimismo, se encontró una media inicial de 92.91 + 4.78 y 92.27+ 2.65, y una media final de 80.55 + 4.03 y 80+ 3.46 para la resina Filtek™ Z 350xt luego de su inmersión a las mismas bebidas. Además, se encontraron diferencias estadísticamente significativas al comparar la microdureza superficial de las resinas compuestas, antes y después de sumergirlas en las bebidas (p=0.000). Por otro lado, no se encontraron diferencias estadísticamente significativas al comparar la disminución que generan ambas bebidas. Sin embargo, al comparar las dos marcas de resina compuesta se observaron diferencias estadísticamente significativas (p=0.000). Conclusiones: La disminución de la microdureza superficial de la resina Filtek™ Z 350 xt luego de ser sumergida a las bebidas Gatorade® y Red Bull® fue menor si se la compara con la resina Tetric® N- Ceram.