Efeito da escovação sobre a rugosidade superficial, perda de massa e adesão de microrganismos na superfície de cimentos de ionômero de vidro utilizados no tratamento restaurador atraumático

Pós-graduação em Ciências Odontológicas - FOAR

Influência da técnica de preparo cavitário na microinfiltração marginal em restaurações de dentes decíduos

Pós-graduação em Odontologia - FOAR

Avaliação de escova ultrassônica em pacientes sob terapia ortodôntica. Estudo in vitro, clínico e microbiológico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Topografia superficial e aderência de Streptococcus mutans no titânio após imersão e escovação com dentifrícios fluoretado e não-fluoretado simulando 10 anos de uso

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da união zircônia-cimento resinoso-dentina com diferentes estratégias de cimentação e de envelhecimento

Pós-graduação em Odontologia Restauradora - ICT

Filmes de SiOx crescidos em substrato de zircônia tetragonal policristalina estabilizada por ítria: influência na durabilidade da adesão a cimentos resinosos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência de diferentes protocolos de jateamento na resistência à flexão e na estabilidade estrutural de uma cerâmica policristalina de zircônia tetragonal parcialmente estabilizada com ítria

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito do tempo e da desinfecção por micro-ondas no desempenho clínico e na quantificação de micro-organismos de um reembasador rígido

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

Efeito de agentes fluoretados e suplementados com trimetafosfato de sódio sobre a erosão e abrasão do esmalte dentário bovino: estudos in situ e ex vivo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Tubos de concreto com adição de resíduos de borracha de pneu

Pós-graduação em Engenharia Civil - FEIS

Resistência à fratura entre a resina acrílica e a resina composta em coroas provisórias implanto-suportadas unitárias imediatas anteriores: estudo in vitro

Pós-graduação em Reabilitação Oral - FOAR

Avanços no torneamento utilizando um porta-ferramentas refrigerado internamente com fluido em mudança de fase

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

Comparison of Physicochemical Surface Conditioning Methods for Adhesion of bis-GMA Resin Cement to Particulate Filler Composite and Surface Characterization

This study compared the effect of physicochemical surface conditioning methods on the adhesion of bis-GMA-based resin cement to particulate filler composite (PFC) used for indirect dental restorations. PFC blocks (N (block)=54, n (block)=9 per group) were polymerized and randomly subjected to one of the following surface conditioning methods: a) No conditioning (Control-C), b) Hydrofluoric acid (HF)etching for 60s (AE60), c) HF for 90s (AE90), d) HF for 120s (AE120), e) HF for 180s (AE180), and f) air-abrasion with 30 mu m silica-coated alumina particles (AB). The conditioned surfaces were silanized with an MPS silane, and an adhesive resin was applied. Resin composite blocks were bonded to PFC using resin cement and photo-polymerized. PFC-cement-resin composite blocks were cut under coolant water to obtain bar specimens (1mmx0.8mm). Microtensile bond strength test (mu TBS)was performed in a universal testing machine (1mm/min). After debonding, failure modes were classified using stereomicroscopy. Surface characterization was performed on a set of separate specimen surfaces using Scanning Electron Microscopy (SEM), X-Ray Dispersive Spectroscopy (XDS), X-Ray Photoelectron Spectroscopy (XPS), and Fourier Transform-Raman Spectroscopy (FT-RS). Mean mu TBS (MPa) of C (35.6 +/- 4.9) was significantly lower than those of other groups (40.2 +/- 5.6-47.4 +/- 6.1) (p<0.05). The highest mu TBS was obtained in Group AB (47.4 +/- 6.1). Prolonged duration of HF etching increased the results (AE180: 41.9 +/- 7), but was not significantly different than that of AB (p>0.05). Failure types were predominantly cohesive in PFC (34 out of 54) followed by cohesive failure in the cement (16 out of 54). Degree of conversion (DC) of the PFC was 63 +/- 10%. SEM analysis showed increased irregularities on PFC surfaces with the increased etching time. Chemical surface analyses with XPS and FT-RS indicated 11-70% silane on the PFC surfaces that contributed to improved bond strength compared to Group C that presented 5% silane, which seemed to be a threshold. Group AB displayed 83% SiO2 and 17% silane on the surfaces.

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.

Streptococcus Mutans Adhesion to Titanium After Brushing with Fluoride and Fluoride-Free Toothpaste Simulating 10 Years of Use

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)