Hydrofluoric acid concentration, time and use of phosphoric acid on the bond strength of feldspathic ceramics
Braz. oral res. (Online)
;
34: e018, 2020. tab, graf
Artículo
en Inglés
| LILACS
| ID: biblio-1089390
ABSTRACT
Abstract The objective of this study was to evaluate the influence of hydrofluoric acid (HF) concentration, etching time, and application of phosphoric acid (PA) followed by neutralization with sodium bicarbonate on the bond strength between a feldspar ceramic and resin cement. Thus, 80 blocks (10 x 12 x 2 mm) of glass ceramic (VM - Vita Mark II - Vita Zahnfabrik) were made and randomly assigned to eight groups (n = 10) according to the factors: HF concentration (5 and 10%), etching time (60 and 120 s), and use of phosphoric acid (PA) (with and without). According to the experimental group, 37% PA (Condac, FGM) was applied after HF etching for 60s. Afterwards, samples were immersed in sodium bicarbonate for 1 min then in an ultrasonic bath in distilled water (5 min) for cleaning. After surface bonding treatment, cylinders (Ø = 2 mm; h = 2 mm) of dual resin cement (AllCem / FGM) were made in the center of each block. The samples were then stored in water (37ºC) for 90 days and submitted to the shear bond test (50 KgF, 1 mm/min). Failure analysis was performed by stereomicroscope and scanning electron microscopy. Data (MPa) were analyzed with 3-way ANOVA and Tukey's test. Only the factor "HF concentration" was significant (p = 0.02). Most failures were of cohesive in ceramic (40%) and mixed types (42.5%). The 10% HF resulted in higher shear bond strength value than the 5% HF. Surface cleaning with phosphoric acid followed by sodium bicarbonate and HF time (60 or 120 seconds) did not influence the resin bond strength to feldspar ceramic.
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Índice:
LILACS (Américas)
Asunto principal:
Ácidos Fosfóricos
/
Recubrimiento Dental Adhesivo
/
Compuestos de Potasio
/
Silicatos de Aluminio
/
Ácido Fluorhídrico
Tipo de estudio:
Estudios de evaluación
Idioma:
Inglés
Revista:
Braz. oral res. (Online)
Asunto de la revista:
Odontología
Año:
2020
Tipo del documento:
Artículo
País de afiliación:
Brasil
Institución/País de afiliación:
Universidadade Federal do Paraná/BR
/
Universidade Estadual de São Paulo/BR
/
Universidade Federal do Rio Grande do Norte/BR
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