Bonding performance of universal adhesives with concomitant use of silanes to CAD/CAM blocks / Associação de adesivos universais com silanos na adesão em blocos de CAD/CAM

ABSTRACT Objective: This study assessed whether the use of a silane coupling agent influence the bond strength of two universal adhesives to ceramic or resin CAD/CAM blocks. Methods: Forty-eight samples were obtained from each resin nano-ceramic hybrid block (RCBs) and lithium disilicate ceramic blocks (LD). Samples were treated with silane with MDP (Monobond - S-MDP), silane without MDP (Prosil - PS), and no silane application (Control - Ctr) followed by universal adhesive with silane (UAS) and without silane (UA) (n=8). Three polyurethane tubes (1.5 mm of internal diameter) were positioned in each sample treated surface and filled with a dual cured resin cement. Bond strength was assessed by microshear bond strength test and failure analysis was performed for all samples. Results: For the RCBs, UAS presented the highest bond strength values (p=0.004). Silane application was not significant in bond strength values (p=0.444). For LD, silane application was significant in bond strength values (p<0.001), but the adhesive was not (p=0.066). Failure analysis showed high prevalence of adhesive failures for both substrates. Conclusion: A silane-containing universal adhesive promoted the best bond strength results to the resin nano-ceramic hybrid block. For bonding to a glass-ceramic CAD/CAM material, additional silane (without MDP) application presented the best results.

RESUMO Objetivo: Este estudo avaliou se o uso de um agente de união silano influencia na resistência de união de dois adesivos universais a blocos CAD/CAM cerâmicos ou resinosos. Métodos: Quarenta e oito amostras foram obtidas de blocos resinosos (RCBs) e cerâmicos de dissilicato de lítio (LD). As amostras foram tratadas com silano contendo: MDP (Monobond - S-MDP), silano sem MDP (Prosil - PS) ou sem aplicação de silano (Control - Ctr) seguido de adesivo universal com silano (UAS) ou sem silano (UA) (n=8). Três tubos de poliuretano (1,5 mm de diâmetro interno) foram posicionados em cada superfície tratada da amostra e preenchidos com um cimento resinoso dual. A resistência de união foi avaliada pelo teste de microcisalhamento e a análise de falha foi realizada para todas as amostras. Resultados: Para os RCBs, UAS apresentou os maiores valores de resistência de união (p=0,004). A aplicação de silano não foi significativa nos valores de resistência adesiva (p=0,444). Para LD, a aplicação de silano foi significativa nos valores de resistência de união (p<0,001), mas o adesivo não (p=0,066). A análise de falhas mostrou alta prevalência de falhas adesivas para ambos os substratos. Conclusão: O adesivo universal contendo silano promoveu os melhores valores de resistência adesiva ao bloco de resina. Para o bloco cerâmico, a aplicação adicional de silano (sem MDP) apresentou melhores resultados.

Effect of commercial silanes on bond strength of resin cement to lithium disilicate ceramic / Efeito de silanos comerciais na resistência de união do cimento resinoso à cerâmica de dissilicato de lítio

The aim of this study was to evaluate the effect of different commercial silanes on microshear bond strength of resin cement to lithium disilicate ceramic. Twenty ceramic samples with 10 mm in length, 10 mm wide and 3 mm in thickness were fabricated, etched with 10% hydrofluoric acid for 20 seconds, and divided into 5 groups, according to the commercial silane applied: G1- RelyX Ceramic Primer (3M ESPE), G2- Angelus Silane, G3- Prosil (FGM), G4- Dentsply Silane (Dentsply) and G5- Bis-Silane (Bisco). Silanes were applied in accordance to manufacturers' recommendations. Addition silicone molds with 1 mm in thickness, 10 mm in diameter and 3 perforations with 1 mm in diameter each one, were placed on ceramic and filled with the resin cement RelyX ARC (3M ESPE) in all groups. Light activation was performed with LED Bluephase G2 (Ivoclar Vivadent) at 1200 mW/cm2, for 30 seconds. Samples were maintained in 100% humidity at 37°C for 24 hours and submitted to microshear test. The data (MPa) were submitted to one-way ANOVA and Tukey test (α=0.05). The results obtained for each group were: G1: 22.39±2.99; G2: 23.35±4.08; G3: 26.05±5.46; G4: 18.56±4.09; G5: 25.26±4.10. Statistical analysis showed significantly lower microshear bond strength for G4. Fracture pattern analysis showed predominance of adhesive failures in G1 and G2. G3 and G5 presented higher percentage of cohesive failures in ceramic, and G4 showed mixed, adhesive and cohesive fractures with similar percentages. It was concluded that different silanes showed influence on the lithium disilicate ceramic ­ resin cement bond strength

O objetivo neste estudo foi avaliar o efeito de diferentes silanos comerciais na resistência de união ao microcisalhamento do cimento resinoso à cerâmica de dissilicato de lítio. Foram confeccionadas 20 amostras de cerâmica (10mm de comprimento, 10mm de largura e 3mm de espessura), condicionadas com ácido fluorídrico a 10% por 20 segundos e divididas em 5 grupos, de acordo com o silano aplicado: G1- RelyX Ceramic Primer (3M ESPE), G2- Silano Angelus, G3-Prosil (FGM), G4- Silano Dentsply e G5-Bis-Silane (Bisco). Matrizes de silicone por adição (1 mm de espessura, 10 mm de diâmetro e 3 perfurações com 1 mm de diâmetro) foram colocadas sobre a cerâmica e preenchidas com cimento resinoso RelyX ARC (3M ESPE). A fotoativação foi realizada com LED Bluephase G2 (Ivoclar Vivadent) a 1200 mW/cm2, por 30 segundos. As amostras foram mantidas em 100% de umidade a 37°C por 24 horas e submetidas ao teste de microcisalhamento. Os dados (MPa) (G1: 22,39+2,99; G2: 23,35+4,08; G3: 26,05+5,46; G4: 18,56+ 4,09; G5: 25,26+4,10) foram submetidos a análise de variância e ao teste de Tukey (p<0,05). A análise estatística mostrou valor de resistência de união significantemente menor para G4. A análise do padrão de fratura mostrou predominância de falha adesiva para G1 e G2. G3 e G5 apresentaram maior porcentagem de falha coesiva em cerâmica, e o G4 apresentou fraturas mista, adesiva e coesiva em igual porcentagem. Concluiu-se que os diferentes silanos apresentaram influência na resistência de união do cimento resinoso à cerâmica de dissilicato de lítio

Different bonding agents effect on adhesive bond strength: lithium disilicate glass ceramic / Efeito de diferentes agentes de união na cimentação adesiva em superfície cerâmica de dissilicato de lítio

Introduction: The silanization of the ceramic surface prior to applying the adhesive and/or resinous materials plays an important role in bond strength. Nowadays, a new family of adhesive systems has been introduced into the market, aiming to simplify the technique of adhesive procedures during cementation. Objective: To investigate the effectiveness of different bonding agents containing silane and primer on Lithium Disilicate Glass Ceramic (LD) surface by shear bond strength tests. Material and method: 130 LD ceramic blocks were included in acrylic resin, polished and washed in ultrasound for 10 minutes. The specimens were divided into 2 groups according to surface treatment: Polished Surface (PS); Hydrofluoric Acid 9.5% - 20s (HF). Each group was divided into 5 subgroups (n = 13) according to bonding agent type: metallic primer containing MDP (ZPrimePlus, Bisco Inc); two traditional silanes (MonobondPlus, IvoclarVivadent / Porcelain Prime, Bisco Inc.); mixture of silane and resin (Kerr Silane, Kerr); mixture of silane and universal adhesive (Single-bond Universal, 3M Espe). The specimens were mounted in a standard device for shear testing (UltradentBonding Assembly), cemented with dual resin cement (RelyX UltimateTM, 3M Espe.) and photo-polymerized for 20s. The samples were tested after 24 hours and 3 months of storage in distilled water at ±36 °C. The data were analyzed by 3-Way Anova and Tukey's test (α = 5%). Result: Shear bond strength (SBS) was significantly influenced by surface treatment, bonding agent used and storage (p <0.001). Conclusion: Adequate adhesive bond strength to Lithium Disilicate Glass Ceramic can be obtained with traditional silanes, combined with HF acid pretreatment surface.

Introdução: A silanização da superfície cerâmica antes da aplicação do adesivo e/ou materiais resinosos desempenha um papel importante na resistência adesiva. Atualmente, uma nova família de sistemas adesivos foi introduzida no mercado, visando simplificar a técnica dos procedimentos adesivos durante a cimentação. Objetivo: Investigar a eficácia de diferentes soluções contendo silano e primer na superfície de cerâmicas de Dissilicato de Lítio (DLT) por meio de testes de resistência adesiva por cisalhamento. Material e método: 130 blocos cerâmicos DLT foram incluídos em resina acrílica, polidos e lavados em ultra-som por 10 minutos. Os espécimes foram divididos em 2 grupos de acordo com tratamento de superfície: Superfície Polida (PS); Ácido Hidro-Fluorídrico 9,5% - 20s (HF). Cada grupo foi dividido em 5 sub-grupos (n = 13) de acordo com o tipo de primer/silano: primer metálico contendo MDP (ZprimePlus, Bisco Inc); dois silanos tradicionais (MonobondPlus, IvoclarVivadent / Porcelain Prime, Bisco Inc.); mistura de silano e resina (Kerr Silane, Kerr); mistura de silano e adesivo universal (Single-bond Universal, 3M Espe). Os espécimes foram montados em um dispositivo padrão (UltradentBonding Assembly) para teste de cisalhamento Bisco Shear Bond Tester), cimentados com cimento resinoso dual (RelyX UltimateTM, 3M Espe.) e foto-polimerizados por 20s. O teste foi realizado após o período de: 24 horas e 3 meses de armazenamento em água destilada à ±36 °C. Os dados foram analisados por 3-Way Anova e Teste de Tukey (α=5%). Resultado: A resistência adesiva ao cisalhamento (SBS) foi significativamente influenciada pelo tipo de tratamento da superfície, pelo tipo de agente de união utilizado e pelo armazenamento (p<0,001). Conclusão: Adequada resistência adesiva pode ser obtida com silanos tradicionais, combinados com o pré-tratamento de superfície com ácido HF.

Effect of self-etching primer associated to hydrofluoric acid or silane on bonding to lithium disilicate

Abstract To evaluate the effect of combining 5% hydrofluoric acid (HF) and silane (SI) with the self-etching ceramic primer on the immediate and after 1-year of water storage on bonding efficacy, conditioning pattern (CP) and chemical interaction (CI) to the lithium disilicate. A total of 16 CAD/CAM blocks of lithium disilicate (LD) were cut into four square sections (n=64). For bonding efficacy evaluation, the LD specimens were divided into 4 groups (n=10): 1) HF+SI; 2) self-etching ceramic primer (MEP); 3) HF+MEP; 4) MEP+SI. After each treatment, an adhesive system was applied and Tygon matrices were filled with a dual-cured resin cement followed by light curing. Cylinder specimens (0.8 mmx0.5mm) were stored in water (37 °C for 24 h or 1-year) and submitted to the μSBS test (2-way ANOVA and Tukey's test; a=0.05). CP and CI were only evaluated qualitatively. No significant difference on the μSBS was observed between groups (p=0.73), but reduced μSBS was observed after 1-year of water storage (p>0.0001). After application of HF+SI and MEP, reduction in a number of siloxane bonds was observed, suggesting the coupling of SI on the LD surface. HF or HF+MEP produced a higher dissolution of the glassy matrix than the use of MEP alone. The MEP can be an alternative to traditional ceramic treatment once the chemical interaction and long-term bond strength were similar between both groups. The association of hydrofluoric acid or silane with a self-etching ceramic primer did not add any benefits in terms of chemical interaction and bonding stability.

Resumo Avaliar o efeito da combinação de ácido fluorídrico ou silano com o primer autocondicionante de cerâmicas sobre a eficácia da união imediata e após 1 ano de armazenamento em água, padrão de condicionamento e interação química desses tratamentos com o dissilicato de lítio. Um total de 16 blocos CAD/CAM de dissilicato de lítio (DL) foram cortados em quatro seções quadradas (n=64). Os espécimes de DL foram divididos em 4 grupos: 1) ácido fluorídrico a 5% + silano (HF + SI); 2) primer autocondicionante de cerâmica (MEP); 3) HF + MEP; 4) MPE + SI. Após cada tratamento, o sistema adesivo foi aplicado e as matrizes Tygon foram preenchidas com cimento resinoso dual (Variolink® II), seguido de fotopolimerização. Espécimes em forma de cilindro (0.8 mmÆ x 0.5 mm), foram armazenados em água (37 °C por 24h ou 1 ano) e submetidos ao teste μSBS (ANOVA dois fatores e teste de Tukey; a=0,05). Para avaliação das interações químicas por Espectroscopia Raman, os espécimes de DL foram divididos em 3 grupos (n=4): 1) sem tratamento (DL); 2) HF + SI; e 3) MEP. Para avaliação do padrão de condicionamento da superfície cerâmica após os tratamentos por MEV, os espécimes de DL foram divididos em 3 grupos (n=3): 1) DL; 2) HF; 3) MEP; e 4) HF + MEP. Ambos os métodos foram avaliados apenas qualitativamente. Não foi observada diferença significativa na μSBS imediata entre os grupos (p=0,73), mas após 1 ano de armazenamento das amostras em água, reduziu μSBS (p>0,0001). HF ou HF + MEP produziram uma maior dissolução da matriz vítrea do que o uso de MEP sozinho. Após a aplicação de SI e MEP, observou-se redução de ligações de siloxano, sugerindo o acoplamento da camada de silano na superfície do DL. O primer autocondicionante cerâmico pode ser uma alternativa ao tratamento cerâmico tradicional, uma vez que a interação química e a resistência de união a longo prazo, quando comparada ao tratamento tradicional foram estatisticamente semelhantes. A associação de ácido fluorídrico ou agente de acoplamento silano com um primer autocondicionante de cerâmicas não agregou nenhum benefício em termos de interação química e estabilidade.

Influence of silane content and filler distribution on chemical-mechanical properties of resin composites

This study investigated the influence of silane concentration and filler size distribution on the chemical-mechanical properties of experimental composites. Experimental composites with silane contents of 0%, 1% and 3% (in relation to filler mass) and composites with mixtures of barium glass particles (median size = 0.4, 1 and 2 μm) and nanometric silica were prepared for silane and filler analyses, respectively. The degree of conversion (DC) was analyzed by FTIR. Biaxial flexural strength (BFS) was tested after 24-h or 90-d storage in water, and fracture toughness, after 24 h. The data were subjected to ANOVA and Tukey’s test (p = 0.05). The DC was not significantly affected by the silane content or filler distribution. The 0% silane group had the lowest immediate BFS, and the 90-d storage time reduced the strength of the 0% and 3% groups. BFS was not affected by filler distribution, and aging decreased the BFS of all the groups. Silanization increased the fracture toughness of both the 1% and 3% groups, similarly. Significantly higher fracture toughness was observed for mixtures with 2 μm glass particles. Based on the results, 3% silane content boosted the initial strength, but was more prone to degradation after water storage. Variations in the filler distribution did not affect BFS, but fracture toughness was significantly improved by increasing the filler size.

Efeito do tratamento de superfície e condição de armazenamento sobre a resistência de união resina-cerâmica / Effect of surface treatment and storage condition on the ceramic-resin bond strength

Uma superfície de cada um de quatro blocos foi polida e submetida aos seguintes tratamentos de superfície: bloco A (HF+S) - microjateamento com Al2O3 de 50 μm (15 s), condicionamento com ácido HF a 9,5% (20 s) e aplicação de silano (3 min); bloco B (HF) - microjateamento e condicionamento com ácido HF; bloco C (S) - microjateamento e silano; e bloco D (CJ) - microjateamento com CoJet Sand e aplicação de silano. O adesivo Scotchbond Multi-Purpose Plus foi aplicado sobre a superfície dos blocos A, B e C, e o adesivo Visio-Bond do sistema CoJet, no D, todos polimerizados, e resina composta (Filtek Z250) foi adicionada em quatro incrementos de 1 mm e fotopolimerizada. Os blocos de resina-cerâmica foram, então, seccionados em dois eixos perpendiculares, produzindo cada um aproximadamente 40 corpos de prova, divididos em dois grupos: grupo “Imediato”, dividido em quatro subgrupos: HF+S/I (n = 19), HF/I (n = 19), S/I (n = 20) e CJ/I (n = 16), armazenados por 24 h em água destilada; e grupo “12m+Tc”, dividido em quatro subgrupos: HF+S/12m (n = 20), HF/12m (n = 20), S/12m (n = 20) e CJ/12m (n = 17), armazenados por 12 meses em saliva artificial, seguidos por termociclagem (800 ciclos). Os valores médios obtidos (HF+S/I = 56,85±16,52(a), HF/I = 51,69±11,34(ab), S/I = 50,73±12,37(ab), CJ/I = 40,13±9,27(bc), HF+S/12m = 42,29±17,34(b), HF/12m = 21,03±7,02(d), S/12m = 13,72±6,24(d), CJ/12m = 26,77±21,07(cd)) foram analisados estatisticamente (ANOVA 2). Observou-se interação entre tratamento de superfície e condição de armazenamento. Condicionamento da superfície cerâmica com ácido HF combinado com silanização propiciou maior μ-TBS à resina após 12 meses de armazenamento em saliva artificial e termociclagem...

One surface of each out of four blocks was polished and subjected to the following surface treatments: A: (HF + S) – sandblasting with AL2O3 50 μm (15 s), etching with 9.5% HF (20 s) and silane application (3 min); B:(HF) - sandblasting and etching with HF; C: (S) – sandblasting and silane; D: (CJ) – sandblasting with CoJet Sand and silane application. A three-step total-etch adhesive was applied (ScotchBond Multi-Purpose Plus) on the surface of the blocks A, B, and C, and the light-cured bonding material, proprietary of the CoJet system (Visio-Bond) on block D, light-cured, and composite resin (Filtek Z250) was added in four 1 mm increments and light cured. The ceramic-resin blocks were then sectioned into two perpendicular axes, each producing approximately 40 specimens, divided into two groups: “immediate” group divided into four subgroups: HF + s / i (n = 19) , HF / i (n = 19), S / I (n = 20) and cj / i (n = 16), stored for 24 h in distilled water; and group “12m + tc”, divided into four subgroups: s/12m + HF (n = 20) HF/12m (n = 20) s/12m (n = 20) and CJ/12m (n = 17) stored for 12 months in artificial saliva followed by thermocycling (800 cycles). The obtained average values (HF + s / i = 56.85 ± 16.52 (a) HF / i = 51.69 ± 11.34 (ab) s / i = 50.73 ± 12.37 (ab), CJ/ i = 40.13 ± 9.27 (bc) + HF s/12m = 42.29 ± 17.34 (b), HF/12m = 21.03 ± 7.02 (d), s / 12m = 13.72 ± 6.24 (d), 26.77 ± 21.07 CJ/12m = (cd)) were statistically analyzed (2-way ANOVA). Interaction between surface treatment and storage conditions were observed. Conditioning of the ceramic surface with HF associated with silanization provided greater μ-TBS values to resin after 12 months of storage in artificial saliva and thermocycling...

Reparación intraoral de una prótesis parcial fija metal-cerámica de seis unidades con resina compuesta: relato del caso / Repair of a six-unit fixed partial denture metal-ceramics with composite resin: case report

Múltiples son los factores que pueden desencadenar fracturas de porcelana en una prótesis parcial fija metal-cerámica, aunque esta situación no siempre determina un reemplazo. La reparación de porcelana mediante el uso de resina compuesta es una alternativa con ventajas de una fácil manipulación y bajo costo. El objetivo del presente artículo es presentar a la resina compuesta como una opción con resultados considerables en la reparación de prótesis metal-cerámicas fracturadas, con alto compromiso estético. Se presenta un caso clínico de reparación intraoral de una prótesis fija metal-cerámica de seis unidades en el sector anterior superior. El tratamiento realizado incluyó fresado de la superficie de porcelana, aislamiento absoluto, grabado ácido con fluoruro de fosfato acidulado, microarenado con óxido de aluminio, silanización, aplicación del adhesivo convencional y tres tipos de resinas compuestas, resina opaca, microhíbrida y resina de nanorelleno. A los 8 meses se evaluó la adaptación de la reparación mediante un explorador e inspección visual, secando con una jeringa triple donde no se observó signos de percolación alguna. Basado en los resultados se puede considerar a esta combinación de resinas compuestas como una alternativa útil en la reparación de porcelana fracturada.

There are multiple factors that can trigger a fracture of porcelain in a metal-ceramic fixed partial denture, although a replacement is not always required. The porcelain repair using composite resin is an alternative with advantages such as easy handling and low cost. The aim of this paper is to present the composite as an option with significant results in the repair of fractured metal-ceramic prostheses, with a high aesthetic commitment. We report a case of intraoral repair of a six-unit metal-ceramic fixed prosthesis in the anterior superior sector. The treatment provided included milling of the surface of porcelain, absolute isolation, acid etching with acidulated phosphate fluoride, aluminium oxide sandblasting, silanization, conventional adhesive application and three types of composite resins: opaque resin, micro-hybrid resin and nanofilled resin. After 8 months we assessed the adaptation of the repair using a surface explorer and visual inspection, drying with a triple syringe. No signs of seepage were observed. Based on the results, this combination of composite resins can be considered as a useful alternative in the repair of broken porcelain.

Effects of silica coating and silane surface conditioning on the bond strength of rebonded metal and ceramic brackets

OBJECTIVE: The aim of this study was to evaluate the effects of tribochemical silica coating and silane surface conditioning on the bond strength of rebonded metal and ceramic brackets. MATERIAL AND METHODS: Twenty debonded metal and 20 debonded ceramic brackets were randomly assigned to receive one of the following surface treatments (n=10 for each group): (1) sandblasting (control); (2) tribochemical silica coating combined with silane. Brackets were rebonded to the enamel surface on the labial and lingual sides of premolars with a light-polymerized resin composite. All specimens were stored in distilled water for 1 week and then thermocycled (5,000 cycles) between 5-55ºC. Shear bond strength values were measured using a universal testing machine. Student's t-test was used to compare the data (α=0.05). Failure mode was assessed using a stereomicroscope, and the treated and non-treated bracket surfaces were observed by scanning electron microscopy. RESULTS: Rebonded ceramic brackets treated with silica coating followed by silanization had significantly greater bond strength values (17.7±4.4 MPa) than the sandblasting group (2.4±0.8 MPa, P<0.001). No significant difference was observed between the rebonded metal brackets treated with silica coating with silanization (15±3.9 MPa) and the sandblasted brackets (13.6±3.9 MPa). Treated rebonded ceramic specimens primarily exhibited cohesive failure in resin and adhesive failure at the enamel-adhesive interface. CONCLUSIONS: In comparison to sandblasting, silica coating with aluminum trioxide particles followed by silanization resulted in higher bond strengths of rebonded ceramic brackets.