Marginal filling and adhesive resistance of bulk fill resin applying 18% edta gel compared with 37% phosphoric acid gel in vitro dental conditioning

Abstract

Resumen: Objetivo. Evaluar el grado de sellado marginal y resistencia adhesiva en resina Bulk -Fill aplicando gel de EDTA al 18% en comparación al gel de ácido fosfórico al 37% en el acondicionamiento dental. Materiales y métodos. El tipo de estudio fue transversal, comparativo, de nivel aplicativo y diseño experimental. La muestra estuvo conformada por 60 dientes con cavidades clase I; se realizó el acondicionamiento con gel de ácido fosfórico, gel del EDTA al 18% en 60 segundos y 90 segundos. El total de la muestras fueron incubados a 37°C por 24 horas, se termocicló con 500 ciclos entre 5 a 55ºC. Para evaluar microfiltración, fueron sumergidos en azul de metileno a 37ºC por 4 horas, fueron seccionadas y observados al estereomicroscopio, para realizar la tracción se empleó la máquina de ensayos universales a una velocidad de 0.75mm/min hasta que se desprendiera el tornillo con la resina. Resultados. Las muestras acondicionadas con ácido fosfórico al 37% presenta mayor microfiltración grado 1 y el promedio de su resistencia adhesiva es de 7.97Mpa, la microfiltración obtenida con EDTA en 60 segundos presenta equidad Abstract: Objective. To evaluate the degree of marginal sealing and adhesive strength in Bulk-Fill resin by applying 18% EDTA gel compared to 37% phosphoric acid gel in dental conditioning. Materials and methods. The study was transversal, experimental comparative, and applied. The sample group consisted of 60 teeth with Class I cavities, which were later subjected to conditioning. This was carried out separately with phosphoric acid gel for 15 seconds, and 18% EDTA gel within two different time frames: 60 and 90 seconds. All samples were incubated at 37ºC for a period of 24 hours and thermocycled between 5 to 55ºC for 500 cycles. To assess microfiltration, they were immersed in methylene blue at 37ºC for 4 hours, and were later sectioned and observed through a stereomicroscope. In order to perform the traction, the conventional testing machine was used at a speed of 0.75mm/min until the screw with the resin detached. Results: Samples conditioned with 37% phosphoric acid showed a greater degree 1 microfiltration and a mean adhesive resistance of 7.97 MPa. The same number of microfiltration grades 1 and 2 was found when using EDTA gel for 60 seconds, with a mean tensile strength of 8.8MPa. On the other hand, applying EDTA gel for 90 seconds showed mostly grade 1 microfiltrations, and to a lesser extent, grade 0 and 2, with a mean resistance of 9.2 MPa. Conclusion:There are no statistically significant differences regarding adhesive strength between the two gels; however, better marginal filling was observed when samples were conditioned with 18% EDTA gel for 90 seconds.

Microleakage in class II restorations of two bulk fill resin composites and a conventional nanohybrid resin composite: an in vitro study at 10,000 thermocycles

“…The cavities in all three groups (A, B and C) were etched with 35% phosphoric acid gel (Ultra-Etch, Ivoclar Vivadent AG, Schaan, Liechtenstein) for 20 s, then rinsed for 5 s and partially dried with pieces of gauze until the dentine was moist. A layer of fifth generation adhesive (Adper Single Bond-2, 3 M ESPE, St. Paul, MN, USA) was then applied with a microbrush to all surfaces of the cavity, followed by a gentle stream of air over the liquid for about 5 s until the solvent evaporates completely [ 24 , 25 ]. Then, a LED light-curing unit (Bluephase N, Ivoclar Vivadent AG, Schaan, Liechtenstein) was used at a light intensity of 1200 mW/cm 2 for 10 s. A circumferential metallic matrix (Automatrix MT, Dentsply, Milford, DE, USA) was adjusted around each cavity for an adequate conformation of the restoration walls.…”

The Microhardness and Surface Roughness Assessment of Bulk-Fill Resin Composites Treated with and without the Application of an Oxygen-Inhibited Layer and a Polishing System: An In Vitro Study

“…Bulk-fill resin composites have become a good product of choice due to their quality in terms of strength and durability, presenting high biocompatibility and better physical properties, such as greater wear resistance and surface hardness, as they are formed by nanoparticles and ceramic metal fillers that improve the resin surface, thus facilitating modeling and polishing with a better esthetic finish [ 7 ]. These characteristics have made its appearance successful, since it facilitates the reduction in clinical working time in a class I cavity by allowing a maximum incremental thickness of 4 mm to be light-cured with limited contraction, making it possible to fill the cavity in a single step [ 1 , 2 ].…”

Surface roughness and oxygen inhibited layer control in bulk-fill and conventional nanohybrid resin composites with and without polishing: in vitro study

“…However, the increase in filler loading also leads to an increase in stiffness and stress during light curing [ 3 ]. For this reason, a new resin composite system called “Bulk Fill or monoincremental” was developed, which can be placed in increments of 4 mm, thus reducing the number of clinical steps and the shrinkage effect, as well as having polymerization accelerators in its composition that reduce light curing time [ 4 , 8 ].…”