Efficacy of Surface Treatments on the Bond Strength of Resin Cements to Two Brands of Zirconia Ceramic

Purpose: To compare the shear bond strength (SBS) of two cements to two Y-TZP ceramics subjected to different surface treatments.Materials and Methods: Zirconia specimens were made from Lava (n = 36) and IPS e.max ZirCAD (n = 36), and their surfaces were treated as follows: no treatment (control), silica coating with 30-mu m silica-modified alumina (Al2O3) particles (CoJet Sand), or coating with liners Lava Ceram for Lava and Intensive ZirLiner for IPS e.max ZirCAD. Composite resin cylinders were bonded to zirconia with Panavia F or RelyX Unicem resin cements. All specimens were thermocycled (6000 cycles at 5 degrees C/55 degrees C) and subjected to SBS testing. Data were analyzed by post-hoc test Tamhane T2 and Scheffe tests (alpha = 0.05). Failure mode was analyzed by stereomicroscope and SEM.Results: With both zirconia brands, CoJet Sand showed significantly higher SBS values than control groups only when used with RelyX Unicem (p = 0.0001). Surface treatment with liners gave higher SBS than control groups with both ceramic brands and cements (p < 0.001). With both zirconia brands, the highest SBS values were obtained with the CoJet and RelyX Unicem combination (> 13.47 MPa). Panavia F cement showed significantly better results when coupled with liner surface treatment rather than with CoJet (p = 0.0001, SBS > 12.23 MPa). In untreated controls, Panavia F showed higher bond strength than RelyX Unicem; the difference was significant (p = 0.016) in IPS e.max ZirCAD. The nontreated specimens and those treated with CoJet Sand exhibited a high percentage of adhesive and mixed A (primarily adhesive) failures, while the specimens treated with liners presented an increase in mixed A and mixed C (primarily cohesive) failures as well as some cohesive failure in the bulk of Lava Ceram for both cements.Conclusion: CoJet Sand and liner application effectively improved the SBS between zirconia and luting cements. This study suggests that different interactions between surface treatments and luting cements yield different SBS: in clinical practice, these interactions should be considered when combining luting cements with surface treatments in order to obtain the maximum bond strength to zirconia restorations.

Internal standard for amorphous pharmaceuticals products quantification and an application of Parametric Rietveld refinement using time, temperature and relative humidity as 'non-crystallographic' parameters

Pós-graduação em Química - IQ

Inorganic elemental analysis and identification of residual monomers released from different glass ionomer cements in cell culture medium

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação da adesão de Staphylococcus spp. em resina acrílica específica para prótese ocular e alteração de cor de botões de íris artificiais, variando a cor e as técnicas de obtenção, ambos após desinfecção química

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biological effects of soft denture reline materials on L929 cells in vitro

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of the addition of antimicrobial agents on shore a hardness and roughness of soft lining materials

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Molhabilidade de material reembasador: efeito dos agentes químicos de limpeza

Risk of mechanical injuries contraindicate brushing and elect chemical agents as appropriate for daily cleaning of dentures relined with resilient materials. It was evaluated the effect of denture cleansers on the wettability of denture relining material (Dentusoft, Dental Medrano). We used 20 discs of acrylic resin thermoactivated VipiCril ® with 30mm diameter and 4mm thick, covered by 2mm Dentusoft ®. Divided into 4grupos were stored in artificial saliva at 37 +1 º C for 30 days, immersed daily for 15minutes in distilled water (GI), Corega ® Tabs (GII), a solution of sodium bicarbonate (GIII) or solution of sodium hypochlorite (GIV) after which, on the soft liner were poured 2 ml of type IV gypsum (Durone IV, Dentsply). Reached the final setting of the gypsum specimens were sectioned vertically and medially, settled water with sandpaper No. 400 and mounted on suitable device for reading (in the right and left) of the contact angle Carl Zeiss microscope (precision, 001). The results were submitted to analysis, showed non-normal distribution, opting for non-parametric test. Kruskal Wallis test performed at 5% significance, there was statistical difference between the groups with lower average contact angle for GII. It was concluded that the chemical cleaning Corega Tabs ® allowed a better adaptation of relining the gypsum studied.