Effect of alternative self-etch applications on dentin bond strength of "No Wait Concept" universal adhesives / Efecto de distintas alternativas de aplicación de los adhesivos universales con concepto de "no espera" en la resistencia adhesiva a la dentina

Abstract This study evaluated the effects of alternative self-etch application modes on resin-dentin microtensile bond strength (µTBS) of three commercially available "no wait" concept universal adhesives. In this study extracted impacted non-carious human third molars were used. The flat surfaces were prepared in mid-coronal dentin and prepared with a 600-grit SiC paper. The three universal adhesives that were used are as follows: Clearfil Universal Bond Quick (CUQ, Kuraray Noritake, Japan), G-Premio Bond (GPB, GC Corp, Japan), and a self-curing universal adhesive "Tokuyama Universal Bond" (TUB; Tokuyama Dental, Japan). The following three different application procedures were used for the dentin surfaces: the adhesives were applied and immediately subjected to air-dry; the adhesives were applied followed by a 10-second wait; or the adhesives were rubbed for 10 seconds. Then composite resin was applied to the dentin surface and light cured. After storage in 37°C distilled water for 24 h, all the bonded teeth were cut into 1mm² sections using a low-speed diamond saw (Micracut 125 Low Speed Precision Cutter, Metkon, Bursa, Turkey) under running water (n=15). The sections were subjected to a tensile force at a crosshead speed of 1mm/min in a testing apparatus (Microtensile Tester, Bisco, IL, USA) and µTBS values were measured. Data were analyzed using the Kruskal-Wallis test and Mann-Whitney U test. Failure modes were analyzed under a stereomicroscope. Prolonged application time significantly affected the µTBS (p<0.005). A significant increase of µTBS on active application was observed for CUQ and GPB. The TUB with an active application had a significantly lower µTBS value compared with the other adhesives. Prolonged application time caused significant improvement of bond strength in all adhesives. The active application is effective at increasing the dentin bond strength except for TUB.

Resumen Este estudio evaluó los efectos de los modos alternativos de aplicación de adhesivos de autograbado en la resistencia de la unión microtensil entre resina y dentina (µTBS) de tres adhesivos universales de concepto "no espera" disponibles en el mercado. En este estudio se utilizaron terceros molares humanos impactados que fueron extraídos. Las superficies planas se prepararon en la dentina coronal media y se prepararon con un papel SiC de 600 granos. Los tres adhesivos universales que se utilizaron son los siguientes: Clearfil Universal Quick Bond (CUQ, Kuraray Noritake, Japón), G-Premio Bond (GPB, GC Corp, Japón), y un adhesivo universal autopolimerizable "Tokuyama Universal Bond" (TUB; Tokuyama Dental, Japón). Se utilizaron los tres procedimientos de aplicación siguientes para las superficies dentinarias: se aplicaron los adhesivos y se sometieron inmediatamente a un secado al aire; se aplicaron los adhesivos y se esperó 10 segundos; o se frotaron los adhesivos durante 10 segundos. Luego se aplicó resina compuesta a la superficie dentinaria y se fotopolimerizó. Después de su almacenamiento en agua destilada a 37°C durante 24 h, todos los dientes unidos se cortaron en secciones de 1mm² utilizando una sierra de diamante de baja velocidad (Micracut 125 Low Speed Precision Cutter, Metkon, Bursa, Turquía) bajo agua corriente (n=15). Las secciones fueron sometidas a una fuerza de tracción a una velocidad de cruceta de 1mm/min en una máquina de prueba universal (Microtensile Tester, Bisco, IL, USA) y se midieron los valores de µTBS. Los datos fueron analizados utilizando la prueba de Kruskal-Wallis y la prueba U de Mann-Whitney. Los modos de falla fueron analizados bajo un estereomicroscopio. El prolongado tiempo de aplicación afectó significativamente a los µTBS (p<0,005). Se observó un aumento significativo de µTBS en la aplicación activa para el CUQ y el GPB. El TUB con una aplicación activa tuvo un valor de µTBS significativamente más bajo comparado con los otros adhesivos. El tiempo de aplicación prolongado causó una mejora significativa de la fuerza de adhesión en todos los adhesivos. La aplicación activa es efectiva para aumentar la fuerza de adhesión de la dentina, excepto para el TUB.

Effect of 2 % chlorhexidine on dentin shear bond strength of different adhesive systems: a 6 months evaluation / Efecto de la clorhexidina al 2 % sobre la resistencia al cizallamiento de diferentes sistemas adhesivos: una evaluación de 6 meses

This study evaluated the effect of chlorhexidine dentin treatment on shear bond strength (SBS) of adhesive systems after different storages. The work included 144 third molars that had their dentin exposed and were divided in 6 groups: G1 (ASB+CHX: Adper Scotchbond 1XT + chlorhexidine 2 % prior Primer); G2(ASB); G3 (APP+CHX: Adper Prompt L-Pop + CHX); G4(APP); G5 (SBU+CHX: Single Bond Universal + CHX); and G6(SBU). Resin build-up was performed and teeth were subdivided regarding storage times (n=8): 72 h, 3 and 6 months. Next, SBS test was performed. At 72 hours, all equivalent groups (same adhesive system, different dentin treatment) showed no significant difference in SBS (P.05). Self-etch adhesive groups (with or without CHX) presented lower SBS compared to other systems (P.05). After 3 and 6 months, all CHX-treated groups presented significantly higher SBS compared to equivalent non-treated groups (P.05). For both storage times, Single Bond Universal presented the highest SBS values within the same dentin treatment (P.05), while Adper Scotchbond and Adper Prompt-L-Pop were not significantly different among them, also within the same dentin treatments [3 months (with CHX: P=.966; without: P=.958) and 6 months (with CHX: P =.887; without: P=.990)]. CHX Dentin disinfection is indicated for all classes of adhesives studied.

Este estudio evaluó el efecto del tratamiento de la dentina con clorhexidina sobre la resistencia al cizallamiento (SBS) de sistemas adhesivos después de diferentes almacenamientos. Se removió el esmalte oclusal a 144 terceros molares y se dejó su dentina media expuesta, posteriormente se dividieron al azar en 6 grupos: G1 (ASB + CHX: Adper Scotchbond 1XT + clorhexidina 2 % antes del Primer); G2 (ASB); G3 (APP + CHX: L-Pop + CHX de Adper); G4 (APP); G5 (SBU + CHX: Single Bond Universal + CHX); y G6 (SBU). Se realizó la aplicación de la resina compuesta y se subdividieron los grupos con respecto a los tiempos de almacenamiento (n = 8): 72h, 3 y 6 meses. A continuación, se realizó la prueba SBS. A las 72 horas, todos los grupos equivalentes (el mismo sistema adhesivo, diferentes tratamientos de dentina) no mostraron diferencias significativas en los valores de SBS (P.05). Los grupos de adhesivo de auto-grabado (con o sin CHX) presentaron valores de SBS más bajos en comparación con otros sistemas (P.05). Después de 3 y 6 meses, todos los grupos tratados con CHX presentaron valores de SBS significativamente mayores en comparación con los grupos no tratados equivalentes (P.05). Para ambos tiempos de almacenamiento, Single Bond Universal presentó los valores de SBS más altos dentro del mismo tratamiento dentinario (P.05), mientras que el Adper Scotchbond y el Adper Prompt-L-Pop no fueron significativamente diferentes entre ellos, también dentro de los mismos tratamientos dentinarios 3 meses (con CHX: P = .966, sin: P = .958) y 6 meses (con CHX: P = .887; sin: P = .990). La desinfección de la dentina con CHX está indicada para todas las clases de adhesivos estudiados.

Physicochemical Properties and Dentin Bond Strength of a Tricalcium Silicate-Based Retrograde Material

Abstract The aim of this study was to evaluate the physicochemical properties and the apical dentin bond strength of the tricalcium silicate-based Biodentine in comparison to white MTA and zinc oxide eugenol-based cement (ZOE). Setting time and radiopacity were evaluated according to ISO 6876:2012 specification. Final setting time, compressive strength and pH were also assessed. Material’s bond strength to the apical root canal dentin was measured by the push-out assay. Data were analyzed by ANOVA and Tukey-Krammer post-hoc test. Biodentine presented the shortest initial (16.2±1.48 min) and final setting time (35.4±5.55 min). Radiopacity of Biodentine (2.79±0.27 mmAl) does not agree with ISO 6876:2012 specifications. On the other hand, Biodentine showed higher compressive strength after 21 days (37.22±5.27 MPa) and higher dentin bond strength (11.2±2.16 MPa) in comparison to white MTA (27.68±3.56 MPa for compressive strength and 2.98±0.64 MPa for bond strength) (p<0.05). Both MTA and Biodentine produced an alkaline environment (approximately pH 10) (p>0.05) compared to ZOE (pH 7). It may be concluded that Biodentine exhibited faster setting, higher long-term compressive strength and bond strength to the apical dentin than MTA and ZOE.

Resumo O objetivo deste estudo foi avaliar as propriedades físico-químicas e a resistência de união à dentina apical do cimento Biodentine em comparação ao MTA branco e cimento à base de óxido de zinco e eugenol (OZE). O tempo de presa e a radiopacidade foram avaliados de acordo com as especificações ISO 6876:2012. O tempo de presa final, a resistência à compressão e o pH também foram avaliados. A resistência de união dos materiais à dentina apical do canal radicular foi avaliada por meio do ensaio push-out. Dados foram analisados por ANOVA e teste complementar de Tukey-Krammer. Biodentine apresentou o menor tempo de presa inicial (16,2±1,48 min) e final (35,4±5,55 min). Os valores de radiopacidade do Biodentine (2,79±0,27 mmAl) não estão de acordo com as especificações ISO 6876:2012. Por outro lado, este material apresentou maior resistência à compressão após 21 dias (37,22±5,27 MPa) e maiores valores de adesão à dentina (11,2±2,16 MPa) em comparação ao MTA branco (27,68±3,56 MPa de resistência à compressão e 2,98±0,64 MPa de resistência de união) (p>0.05). Ambos os materiais produziram ambiente alcalino (aproximadamente 10) (p>0.05) em comparação ao OZE (pH 7). Pode-se concluir que o Biodentine demonstrou endurecimento mais rápido e apresentou maior resistência à compressão e resistência de união à dentina apical do que MTA e OZE.

Influencia del tiempo de almacenamiento en la resistencia de unión a la dentina desproteinizada: utilizando tres diferentes adhesivos dentales / Influence of storage time on the bond strength to dentin deproteinized: using three different dental adhesives

Este estudio "in vitro" tuvo como objetivo evaluar a lo largo del tiempo (24 horas y 6 meses), el tratamiento del sustrato dentinario (desmineralización, desproteinización y antioxidante) y su influencia en la resistencia de la unión a la dentina, con tres adhesivos dentales. Noventa terceros molares humanos sanos recién extraídos se utilizaron: 72 para el ensayo de microtracción y 18 para análisis de interfaz en Microscopio electrónico de barrido (MEB). Estos fueron divididos aleatoriamente en tres grupos: AdperTM Scotchbond Multi-Uso (n=24); AdperTM Single Bond 2 (n=24); y XP Bond (n=24). Cada grupo fue dividido en 6 subgrupos (n = 4) de acuerdo con el tratamiento de la superficie dentinaria y el tiempo de evaluación. Sobre la zona de unión de todos los cuerpos de prueba se hizo un cilindro de 5 mm con resina compuesta FiltekTM Z250 (3M ESPE). Para el ensayo de microtracción se obtuvieron palillos (0,8 mm2). El análisis estadístico mostró que, a excepción del adhesivo XP Bond (65,07 ± 23,05), cuando se utilizó NaOCl, las otras medias fueron mayores en el tiempo de 6 meses que en 24 horas. El análisis del MEB mostró un patrón morfológico con capa híbrida uniforme y tags regulares. Considerando los resultados, se concluyó que la técnica con NaOCl dependió del sistema adhesivo y el tiempo, que la neutralización con el ascorbato de sodio revertió los valores obtenidos con NaOCl para ciertos grupos

This in vitro study investigated the influence of time (24h and 6 months) the treatment of the dentin substrate (demineralization, deproteinization, and antioxidant), and its influence on the bond strength using three dental adhesives. Ninety healthy human third molars freshly extracted were used for the microtensile test (n=72) and SEM analysis (n=18) randomly divided into three groups: AdperTM Scotchbond Multipurpose (n = 24); AdperTM Single Bond 2 (n = 24) and XP Bond (n = 24). Each group was further divided into 6 subgroups (n = 4) according to the treatment and evaluation time. A cylinder of 5mm was produced on the area of union using the composite resin Z250 (3M ESPE) and sticks of 0.8mm2 were obtained for the microtensile test. The statistical analysis showed that when NaOCl was used the average bond strength at 6 months was higher for most groups, except for XP Bond (60.48 ± 21.14 MPa). SEM analysis showed an uniform hybrid layer morphology and regular tags. Considering the results the effects of the NaOCl treatment on the bond strength was dependent on the adhesive system and time, and neutralization with sodium ascorbate reversed the values obtained with NaOCl for certain groups

Effect of cavity shape, bond quality and volume on dentin bond strength / 대한치과보존학회지

The aim of this study was to evaluate the effect of cavity shape, bond quality of bonding agent and volume of resin composite on shrinkage stress developed at the cavity floor. This was done by measuring the shear bond strength with respect to iris materials (cavity shape; adhesive-coated dentin as a high C-factor and Teflon-coated metal as a low C-factor), bonding agents (bond quality; Scotchbond(TM) Multi-purpose and Xeno(R)III) and iris hole diameters (volume; 1 mm or 3 mm in diameter x 1.5 mm in thickness). Ninety-six molars were randomly divided into 8 groups (2 x 2 x 2 experimental setup). In order to simulate a Class I cavity, shear bond strength was measured on the flat occlusal dentin surface with irises. The iris hole was filled with Z250 restorative resin composite in a bulk-filling manner. The data was analyzed using three-way ANOVA and the Tukey test. Fracture mode analysis was also done. When the cavity had high C-factor, good bond quality and large volume, the bond strength decreased significantly. The volume of resin composite restricted within the well-bonded cavity walls is also be suggested to be included in the concept of C-factor, as well as the cavity shape and bond quality. Since the bond quality and volume can exaggerate the effect of cavity shape on the shrinkage stress developed at the resin-dentin bond, resin composites must be filled in a method, which minimizes the volume that can increase the C-factor.