Active and Passive Application of the Phosphoric Acid on the Bond Strength of Lithium Disilicate

Abstract

The objective of this study was to evaluate the effect of passive or active phosphoric acid (PA) application after hydrofluoric acid (HA) treatment on the microshear bond strength of lithium disilicate. Thirty ceramic discs were made with IPS Emax 2 (10 mm thick and 10 mm diameter). The specimens were divided into 3 groups, A: 9.6% HA application; AF: 9.6% HA application + cleaning with 37% PA in passive mode and AFF: 9.6% HA application + cleaning with 37% PA in active mode. For the microshear test, four tygons (0.9 mm diameter and 0.2 mm high) were filled with resin cement (RelyX Ultimate) and placed on the ceramic disks. After testing, the fracture modes were examined under scanning electron microscopy. Data were analyzed by one-way ANOVA and Tukey's post test (α=0.05). The bond strength values were significantly higher in Group AFF (11.0±2.5 MPa) compared with group A (8.1±2.6 MPa) (p<0.002). AF group was not statistically different (9.4±2.5 MPa) from Group A. It was concluded that the active application of 37% PA after 9.6% HA increases the microshear bond strength values between the resin cement and lithium disilicate ceramic.

Effect of different surface treatments on bond strength of different resin cements to lithium disilicate glass ceramic: an in vitro study

“…Giraldo et al [33] observed that the active application of phosphoric acid after 9.6% HF acid increases the microshear BS values between the resin cement and LDC. In the study of Lise et al [34], HF acid etching showed higher microshear BS values than those observed in the control group.…”

Diferentes Áreas Adesivas Afetam a Resistência De União Ao Microcisalhamento?

“…Neste estudo, o menor diâmetro utilizado foi de 0,55 mm, em que observamos maior dificuldade na precisão do corte do tubo, na execução da metodologia, perdendo maior quantidade de corpos-de-prova, quando comparado ao diâmetro de 0,76 mm, por defeitos de posicionamento e de cimentação. Talvez as dificuldades na execução destes testes de microcisalhamento levem a comunidade científica a retornar para diâmetros maiores (GIRALDO et al, 2016;CEKIC-NAGAS et al, 2016).…”

Molar Incisor Hypomineralization: the use of Digital Smile Design (DSD) in the Esthetic and Functional Recovery of Teeth

“…[5][6][7] The esthetic appearance is the main reason why patients with color changes seek dental therapy. 4,14,[20][21][22][23][24][25] Treatment planning involves different factors such as severity and type of the alteration, whether or not malocclusion is present, age and socioeconomic situation of patients, and gingival health. 9,12,23 Therefore, it is extremely important for a multidisciplinary team to participate in the evaluation, diagnosis, and combination of surgical/restorative techniques to resolve the esthetic and functional changes, 9,10,13 particularly in more complex clinical cases such as the one presented in this article.…”

“…4,15,20 Newly developed pressable lithium disilicate-reinforced glass ceramics, such as the IPS emax Press™ system, has become the ceramic of choice for many dentists due to the satisfactory marginal fit and improved physical properties, such as higher biaxial and fracture strength and preservation of esthetic characteristics, which precisely indicate them for the fabrication of ceramic veneers. 4,24 This is an etchable ceramic composed of 70% of lithium disilicate crystals. Its composition includes two crystalline phases and one glass phase.…”

“…The extremely esthetic dental ceramics have the potential to reproduce translucence/opacity and variation in color, texture, and brightness of natural teeth. 18,24 Their surface is extremely smooth, preventing the adherence of exogenous pigments. As a result of their development, it was possible to produce ceramic veneers or contact lenses for anterior…”