ABSTRACT
AIM: To assess in vitro the effect of two novel phase separated borosilicate glasses (PSBS) in the system SiO2 -B2 O3 -K2 O-CaO-Al2 O3 on dental pulp cells; and to compare their bioactivity and mechanical properties to a conventional fluoroaluminosilicate glass ionomer cement namely FUJI IX. METHODOLOGY: The cytocompatibility assessment of the two novel borosilicate glasses, one without alumina (PSBS8) and one containing alumina (PSBS16), was performed on cultured primary human pulp cells. Alamar blue assay was used to assess cell metabolic activity and cell morphology was evaluated by confocal imaging. The bioactivity in Stimulated Body Fluid was also evaluated after 1 and 3 weeks of immersion using SEM-EDX analysis. Vickers microhardness and flexural strength were assessed after incorporating the glass particles into a commercial glass ionomer cement (GIC) liquid containing both polyacrylic and polybasic carboxylic acid. RESULTS: The data revealed that the two borosilicate glasses enhanced cell viability ratios at all-time points in both direct and indirect contact assays. After 3 days of contact, PSBS8 without alumina showed higher viability rate (152%) compared to the PSBS16 containing alumina (145%) and the conventional glass ionomer particles (117%). EDX analysis confirmed an initial Ca/P ratio of 2.1 for 45S5K and 2.08 for PSBS8 without alumina after 3 weeks of immersion. The cement prepared using PSBS8 showed significantly higher Vickers hardness values (p = .001) than that prepared using PSBS16 (46.6 vs. 36.7 MPa). After 24 h of maturation, PSBS8 (without alumina) exhibited a flexural strength of 12.9 MPa compared to a value of 16.4 MPa for the commercial control. PSBS8 without alumina had a higher strength than PSBS16 with alumina, after 1 and 7 days of maturation (p = .001). CONCLUSIONS: The present in vitro results demonstrated that the borosilicate bioactive glass without alumina enhanced pulp cell viability, spreading and acellular bioactivity better than the conventional GIC and the experimental borosilicate glass containing alumina.
Subject(s)
Dental Pulp , Silicon Dioxide , Aluminum Oxide , Glass Ionomer Cements/pharmacology , Humans , Materials TestingABSTRACT
Evaluar el efecto del termociclado y el tipo de acondicionamiento en el sellado de una resina microhibrida. 20 terceros molares sanos se dividieron en dos grupos en función del sistema adhesivo. Estos a su vez se subdividieron en dos de acuerdo al termociclado. Se realizaron cavidades clase V y posteriormente se obturaron con el sistema adhesivo y el material utilizado. Los dientes se termociclaron en agua y se colocaron en solución de fuscina al 0.5% durante 24 horas. Se evaluó la microfiltración del material utilizado. El grupo Esthet-X-Xeno no presentó microfiltración, en contraste con el grupo Esthet-X-P&B NT quien presentó una media de 32 m (1000 Ciclos) en la pared oclusal y 654 m (1000 ciclos) en la pared gingival. Al realizar ANOVA y test DSH de Tukey entre la variable microfiltración y termociclado indican que el termociclado influye en la capacidad de sellado del material, siendo los valores estadísticamente significativos entre las muestras que fueron sometidas a termociclado y las que no fueron sometidas a termociclado (p=0,0000). Asimismo, ANOVA y test post hoc de comparaciones múltiples Tukey entre la variable microfiltración y tipo de acondicionamiento indican que existen diferencias estadísticamente significativas entre las dos variables, observándose que el grupo Esthet-X usado con adhesivo Xeno III no presento niveles de microfiltración y los mejores promedios de sellado, tanto para la pared oclusal como en la pared gingival al ser comparados con el grupo Esthet-X- Prime&Bond p=0,0000). El termociclado y el acondicionamiento de la superficie influyen en la capacidad de sellado de la resina microhibrida. El termociclado disminuye la capacidad de sellado con mayor tendencia en el margen gingival. Usar un adhesivo autograbador con una resina microhíbrida permite el completo sellado.
To evaluate the effect of thermocycling and the kind of conditioning in the sealing of a microhybrid resin. 20 healthy third molars were divided in two groups in terms of the adhesive system. At the same time, those were divided in two groups in terms of thermocycling. Class V cavities were made and then filled with the adhesive system and the used material. Teeth were thermocycled in water and stored in fuchsin solution at 0.5% during 24 hours. Microleakage of the used materials was evaluated. The Esthet-X-Xeno group did not show microleakage, opposite to the Esthet-X-P&B NT group which got a mean of 32 m (1000 Cycles) in the occlusal wall and a mean of 654 m (1000 cycles) in the gingival wall. The ANOVA and Tukey's DSH between the variable microleakage and thermocycling they indicate that the thermocycling influences in the capacity of seal of the material, being the significant statistics between the samples that were put under thermocycling and those that were not put under thermocycling (p=0,0000). Also, the ANOVA and Tukey's DSH between the variable microleakage and type of preparation indicate that statistically significant differences between the two variables exist, being observed that the Esthet-X group used with adhesive Xeno III presents smaller values of microleakage and the best averages of seal, as much for the oclusal wall as in compared the gingival wall the being with the group Esthet-X- Prime& Bond (p=0,0000). The thermociclyng and conditioning of the surface have an influence on the sealing ability of the microhybrid resin. Thermocycled diminishes the sealing ability with a higher trend in the gingival margin. Using a selfetching adhesive with a microhybrid resin allow complete sealing.
