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Objective: This study aimed to evaluate the bond strength of a universal adhesive to dentin (µTBS) using different time periods of airborne particle abrasion (APA) and two types of acid etching. Methods: Seventy-two human third molars were divided into 9 groups (n=8) according to dentin pretreatment: APA duration (0, 5, or 10s) and acid etching (no acid - NA, 37% phosphoric acid - PhoA, or 1% phytic acid - PhyA). APA was performed at a 0.5 cm distance and air pressure of 60 psi using 50 µm aluminum oxide particles. Afterwards, two coats of Single Bond Universal adhesive (3M) were applied to the dentin surface. Composite blocks were built using the incremental technique, sectioned into 1×1 mm slices and subjected to microtensile bond strength (µTBS) testing. Fracture patterns and surface topography of each dentinal pretreatment were evaluated using a Scanning electron microscope (SEM). Bond strength data were analyzed using two-way ANOVA and Bonferroni post-hoc tests. Results: The group that received pretreatment with 5s APA and PhoA presented higher µTBS values among all groups, which was statistically different when compared with the PhoA, 10APA+PhoA, and 5APA+PhyA groups. PhyA did not significantly influence the bond strength of the air-abraded groups. Finally, adhesive failure was considered the predominant failure in all groups. Conclusion: Dentin pretreated by airborne particle abrasion using aluminum oxide demonstrated an increase in bond strength when abraded for 5 seconds and conditioned with phosphoric acid in a universal adhesive system.

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Abstract This study aimed to investigate the failure behavior of 3 mol.% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) prosthetic crowns air-abraded with aluminum oxide (AO) particles of different sizes. Ninety ceramic premolar crowns were produced with 3Y-TZP frameworks veneered with porcelain. Crowns were randomly divided into three groups, according to the size of the air abrasion AO particles (n = 30): (GC) untreated (control); (G53) 53 µm; (G125) 125 µm. Air abrasion was performed with 0.25 mpa pressure, 10-mm distance, for 10 s. Crowns were adhesively cemented to dentin analog abutments. Specimens were loaded in compression to failure, in 37oC distilled water, using a universal testing machine (n = 30). Fractographic analysis was performed using a stereomicroscope and SEM. The roughness of the crown's inner surface was evaluated using an optical profilometer (n = 10). Fracture load data were statistically analyzed with Weibull analysis and roughness data with Kruskal-Wallis (α = 0.05). GC had the lowest characteristic fracture load (L0), while G53 and G125 had higher and statistically similar L0 values. The Weibull modulus (m) was similar among groups. The failure modes observed were catastrophic failure and porcelain chipping. There were no differences between the roughness parameters for the experimental groups (p > 0.05). The size of the AO particles did not affect the fracture load and failure mode of 3Y-TZP crowns. Air abrasion with 53 µm and 125 µm particles resulted in a higher fracture load of ceramic crowns than the untreated group while maintaining their reliability and surface characteristics.

Resumo O objetivo deste estudo foi investigar o efeito do jateamento com óxido de alumínio (AO) com diferentes tamanhos de partículas no comportamento de fratura de coroas protéticas de zircônia tetragonal estabilizada com 3 mol% de ítria (3Y-TZP). Noventa coroas cerâmicas de pré-molares foram produzidas com infraestruturas de 3Y-TZP recobertas com porcelana. As coroas foram divididas aleatoriamente em três grupos, de acordo com o tamanho das partículas de AO do jateamento (n = 30): (GC) não tratada (controle); (G53) 53 µm; (G125) 125 µm. O jateamento foi realizado com pressão de 0,25 MPa, distância de 10 mm, por 10 s. As coroas foram cimentadas adesivamente em pilares análogos à dentina. As coroas foram testadas em compressão até a falha, em água destilada a 37ºC, usando uma máquina universal de ensaios (n = 30). A análise fractográfica foi realizada usando estereomicroscópio e MEV. A rugosidade da superfície interna das coroas foi avaliada usando um perfilômetro óptico (n = 10). Os dados de carga de fratura foram analisados ​​estatisticamente com análise de Weibull e os dados de rugosidade com Kruskal-Wallis (( = 0,05). GC apresentou a menor carga característica de fratura (L0), enquanto G53 e G125 apresentaram valores de L0 maiores e estatisticamente semelhantes. O módulo de Weibull (m) foi semelhante entre os grupos. Os modos de falha observados foram falha catastrófica e lascamento da porcelana. Não houve diferenças entre os parâmetros de rugosidade para os grupos experimentais (p > 0,05). O tamanho das partículas de AO não afetou a carga de fratura e o modo de falha das coroas 3Y-TZP. O jateamento com partículas de 53 µm e 125 µm resultou em maior carga de fratura das coroas cerâmicas do que o grupo não tratado, mantendo sua confiabilidade e características de superfície.

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Objective: to evaluate the effect of novel zirconia surface treatment method on shear bond strength between zirconia and veneering porcelain compared to air abrasion and CoJet surface treatment methods. Material and Methods: twenty-one zirconia ceramic discs were fabricated with diameter of 7mm and 3mm thickness and divided according to surface treatment into three subgroups, control group I: Air Abrasion (n=7), group II: CoJet (n=7) and group III: Z-etch (n=7). Porcelain was built over the zirconia specimens with a customized mold and fired in a ceramic furnace. All specimens were thermocycled (20000 cycles) between 5°C ­ 55 °C with a dwell time of 30 seconds in distilled water and shear bond strength of veneering porcelain to each zirconia specimen was tested using a universal testing machine. Results: numerical data were explored for normality by checking the distribution of data and using tests of normality (Kolmogorov-Smirnov and Shapiro-Wilk tests). One-way ANOVA test was used to compare between the groups. There was a statistically significant difference between the three groups (P-value = 0.002, Effect size = 0.503). Pair-wise comparisons between groups revealed that Z-etch showed the statistically significantly highest mean shear bond strength. Conclusion: zirconia coating using z-etch is showing promising results in promoting higher bond strength than conventional surface treatment methods as air abrasion and silica coating (AU)

Objetivo: avaliar o efeito do novo método de tratamento de superfície de zircônia na resistência ao cisalhamento entre a zircônia e a porcelana de cobertura em comparação com os métodos de abrasão a ar e jateamento com CoJet. Material e Métodos: vinte e um discos de zircônia foram confeccionados com diâmetro de 7mm e espessura de 3mm e divididos de acordo com o tratamento de superfície em três subgrupos, grupo controle I: Abrasão a ar (n=7), grupo II: CoJet (n=7) e grupo III: Z-etch (n=7). A porcelana foi aplicada sobre os espécimes de zircônia com um molde personalizado e sinterizada em forno de cerâmica. Todos os espécimes foram termociclados (20.000 ciclos) entre 5°C - 55°C com um tempo de permanência de 30 segundos em água destilada e a resistência ao cisalhamento da porcelana de cobertura foi testada através de uma máquina de ensaio universal. Resultados: os dados numéricos foram avaliados quanto à normalidade, verificando a distribuição dos dados e utilizando testes de normalidade (testes de Kolmogorov-Smirnov e Shapiro-Wilk). O teste ANOVA de um fator foi utilizado para comparar os grupos. Houve uma diferença estatisticamente significativa entre os três grupos (P-valor = 0,002, tamanho do efeito = 0,503). As comparações pareadas entre os grupos revelaram que o Z-etch apresentou a resistência de união ao cisalhamento estatisticamente significativamente mais alta. Conclusão: o revestimento de zircônia utilizando Z-etch mostrou resultados promissores para o aumento da resistência de união em comparação aos métodos convencionais de tratamento de superfície, como abrasão a ar e revestimento de sílica (AU)

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Poliéter-éter-cetona (Polyetheretherketone - PEEK) é um polímero de excelentes propriedades mecânicas, o que o torna um potencial candidato para substituir ligas metálicas em diversas especialidades odontológicas. Quando utilizado como infraestrutura para confecção de próteses odontológicas, a adesão do PEEK ao material de revestimento estético é determinante para a longevidade do tratamento, embora a baixa energia de superfície e grande estabilidade química do polímero tornem essa adesão um desafio a ser superado. Objetivo: Responder à pergunta: "Outros tratamentos de superfície do PEEK geram resistências de união superiores ao adesivo comercial?" Métodos: A busca foi feita nas bases Pubmed, , LILACS, Scopus, Web of Science, EMBASE, ProQuest e Google Scholar em junho de 2023 e não houve restrição relativa ao idioma ou à data de publicação dos estudos. Foram utilizados os seguintes termos e operadores booleanos: "polyether ether ketone" [MH] OR "polyether ether ketone" OR "polyetheretherketone" OR "polyetherketoneketone" OR "PEEK" AND "shear strength" [MH] OR "shear strength" OR "shear bond strength" OR "tensile bond strength" OR "shear" OR "tensile" OR "microtensile" OR "microshear" OR "bonding" OR "bond strength" OR "microtensile strength" OR "microshear bond strength" OR "bond" OR "adhesion" OR "bond integrity" OR "bonded" OR "Bonding Strength" OR "Bonding Behavior" OR "Adhesive Performance" OR " surface bonding" OR "tensile strength" [MH] OR "tensile strength". Foram incluídos exclusivamente estudos in vitro. Resinas compostas e resinas acrílicas foram consideradas como materiais de revestimento para PEEK. A média e o desvio padrão expressos em MPa e obtidos a partir de testes de cisalhamento e tração foram utilizados para relatar a resistência de união entre o PEEK e os materiais de revestimento. As meta-análises foram realizadas e a ferramenta Cochrane Collaboration avaliou o risco de viés (RoBDEMAT). Resultados: Foram selecionados 23 estudos. A resistência de união entre PEEK e resina composta foi favorecida pelo uso do adesivo (P<0,00001), independentemente do tipo de adesivo. O pré-tratamento com jato de areia Al2O3 (P<0,00001), ácido sulfúrico (P<0,00001), plasma frio (P=0,0006) e laser (P<0,00001) mostrou-se eficiente, embora o condicionamento com solução piranha não tenha tido efeito estatisticamente significativo (P=0,47). Conclusão: A aplicação de ácido sulfúrico antes do adesivo apresentou melhores resultados de resistência de união em comparação ao uso isolado do adesivo.

Polyether-ether-ketone (Polyetheretherketone - PEEK) is a polymer with excellent mechanical properties, which makes it a potential candidate to replace metallic alloys in several dental specialties. When used as an infrastructure for the manufacture of dental prostheses, the adhesion of PEEK to the aesthetic coating material is decisive for the longevity of the treatment, although the low surface energy and great chemical stability of the polymer make this adhesion a challenge to be overcome. Objective: Answer the question: "Do other PEEK surface treatments generate bond strengths superior to commercial adhesive?" Methods: The search was carried out in the Pubmed, LILACS, Scopus, Web of Science, and EMBASE, ProQuest and Google Scholar databases in June 2023 and there were no restrictions regarding the language or publication date of the studies. The following terms and bolean operators were used: "polyether ether ketone" [MH] OR "polyether ether ketone" OR "polyetheretherketone" OR "polyetherketoneketone" OR "PEEK" AND "shear strength" [MH] OR "shear strength" OR " shear bond strength" OR "tensile bond strength" OR "shear" OR "tensile" OR "microtensile" OR "microshear" OR "bonding" OR "bond strength" OR "microtensile strength" OR "microshear bond strength" OR "bond" OR "adhesion" OR "bond integrity" OR "bonded" OR "Bonding Strength" OR "Bonding Behavior" OR "Adhesive Performance" OR "surface bonding" OR "tensile strength" [MH] OR "tensile strength". Only in vitro studies were included. Composite resins and acrylic resins were considered as coating materials for PEEK. The mean and standard deviation expressed in MPa and obtained from shear and tensile tests were used to report the bond strength between PEEK and coating materials. Meta-analyses were performed and the Cochrane Collaboration tool assessed the risk of bias (RoBDEMAT). Results: 23 studies were selected. The bond strength between PEEK and composite resin was favored by the use of the adhesive (P<0,00001), regardless of the type of adhesive. Pretreatment with Al2O3 sandblasting (P<0,00001), sulfuric acid (P<0,00001), cold plasma (P=0,0006) and laser (P<0,00001) proved to be efficient, although conditioning with piranha solution did not have a statistically significant effect (P=0,47). Conclusion: The application of sulfuric acid before the adhesive showed better results in bond strength compared to the use of the adhesive alone.

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RESUMEN Los selladores de fosas y fisuras han demostrado ser una alternativa eficiente y eficaz para proteger las superficies oclusales del desarrollo de lesiones cariosas. Se realiza una revisión del aire abrasivo usado en odontología resturadora y se presenta un caso clínico del uso de esta tecnologia para la colocación de selladores de fosas y fisuras.

ABSTRACT Pit and fissure sealants have proven to be an efficient and effective alternative to protect occlusal surfaces from the development of carious lesions. A review of the abrasive air used in restorative dentistry is carried out and a clinical case of the use of this technology for the placement of pit and fissure sealants is presented.

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Aim: To evaluate the effect of different surface treatments and adhesive approaches on the microshear bond strength of resin cement to a polymer-infiltrated ceramic network (PICN). Methods: PICN blocks were randomly assigned into 9 groups (n=10): CTRL: no treatment; HF: 5% hydrofluoric acid etching; HF-S: HF + silane; HF-S-A: HF-S + adhesive (Adper Single Bond 2); HF-UA: HF + universal adhesive (Single Bond Universal); SB: sandblasting with 50 µm Al2O3 particles; SB-S: SB + silane; SB-S-A: SB-S + adhesive; SB-UA: SB + universal adhesive. Resin cement microcylinders (Ø = 0.96 mm; height = 1 mm) (RelyX Ultimate) were built upon the PICN surface after roughness and contact angle measurements. Next, microshear bonding tests (µSBS) were performed (0.5 mm/min) after water storage (37ºC, 90 days) and thermocycling (12,000 cycles; 5ºC-55ºC). Failure modes were observed under stereomicroscope. Bond strength data were analyzed by two-way ANOVA/Tukey's test and t-tests. Kruskal-Wallis/Dunn's tests were conducted for roughness and contact angle data (α = 0.05). Results: A rougher surface and lower contact angles were observed for Sandblasting. HF-S (18.54 ± 2.03 MPa), SB-S (19.00 ± 1.66 MPa) and SB-UA (18.07 ± 2.36 MPa) provided the highest bond strength values, followed by the other treated groups. The CTRL group resulted in lower bond strength (7.18 ± 2.34 MPa). Conclusion: Hydrofluoric acid etching followed by silane application and sandblasting followed by silane or universal adhesive are useful clinical steps to enhance bonding to PICN. Adhesive applications after HF etching have no advantages in bonding to PICN

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ABSTRACT Introduction: Orthodontic treatment for adults is currently increasing, and therefore the need to bond brackets to restorations and temporary crowns. The use of CAD/CAM PMMA provisional restorations for orthodontic purposes have not yet been described, and there is currently insufficient information regarding the strength of bracket adhesion. Objective: This study aimed at evaluating the effects of thermocycling (TC) and surface treatment on shear bond strength (SBS) of brackets to different provisional materials. Methods: Forty specimens were made from each material [PMMA (Telio Lab), bis-acryl (Telio CS C&B), and PMMA CAD/CAM (Telio CAD)], sandpapered, and divided according to surface treatment (pumiced or sandblasted) and TC (half of the samples = 1,000 cycles, 5°C/55°C water baths) (n = 10/group). Stainless-steel brackets were bonded to the specimens (using Transbond XT), and SBS testing was performed. Data were analyzed by three-way ANOVA and LSD post-hoc tests (α = 0.05). Failure types were classified with adhesive remnant index (ARI) scores. Results: SBS values ranged from 1.5 to 14.9 MPa. Sandblasted bis-acryl and sandblasted auto-curing PMMA groups presented similar values (p> 0.05), higher than the CAD/CAM material (p< 0.05), with or without TC. When thermocycled, pumiced bis-acryl showed higher SBS than pumiced acrylic (p= 0.005) and CAD/CAM materials (p= 0.000), with statistical difference (p= 0.009). TC showed negative effect (p< 0.05) for sandblasted bis-acryl and pumiced acrylic groups. ARI predominant score was mostly zero (0) for CAD/CAM, 1 and 2 for bis-acryl, and 1 for acrylic groups. Conclusion: In general, bis-acryl material showed the highest SBS values, followed by acrylic and CAD/CAM materials, which showed SBS values lower than an optimum strength for bonding brackets.

RESUMO Introdução: Atualmente, a demanda por tratamento ortodôntico em adultos tem aumentado. Consequentemente, também tem aumentado a necessidade de se colar braquetes em restaurações e coroas provisórias. O uso de restaurações provisórias de PMMA CAD/CAM com finalidade ortodôntica ainda não foi descrito e, até a presente data, não há informação suficiente sobre a resistência da colagem dos braquetes a esse tipo de material. Objetivo: O presente estudo teve como objetivo avaliar os efeitos da termociclagem (TC) e do tratamento de superfície sobre a resistência da colagem ao cisalhamento (RC) de braquetes colados em diferentes materiais provisórios. Métodos: Quarenta espécimes foram confeccionados de cada material: resina acrílica PMMA (Telio Lab), resina bisacrílica (Telio CS C&B), e PMMA CAD/CAM (Telio CAD). Em seguida, foram lixados e divididos de acordo com o tratamento de superfície (polidos ou jateados) e TC (metade da amostra - 1.000 ciclos de imersão em água a 5°C e 55°C) (n = 10/grupo). Braquetes de aço inoxidável foram colados aos espécimes (utilizando Transbond XT) e realizou-se o teste de RC. As informações foram analisadas por meio dos testes ANOVA de três vias e post-hoc LSD (α?#8197;= 0,05). Os tipos de falha foram classificados de acordo com os escores do índice de adesivo remanescente (ARI). Resultados: Os valores de RC variaram de 1,5 a 14,9 MPa. Os grupos de resina bisacrílica jateada e de PMMA autopolimerizável jateado apresentaram valores semelhantes (p> 0,05), superiores ao do material CAD/CAM (p< 0,05) com ou sem TC. Quando submetido à TC, o grupo de resina bisacrílica polida apresentou resistência ao cisalhamento maior do que os grupos de resina acrílica polida (p= 0,005) e do material CAD/CAM (p= 0,000), com diferença estatística (p= 0,009). A TC apresentou efeito negativo (p< 0,05) para os grupos de resina bisacrílica jateada e de resina acrílica polida. O escore ARI = 0 foi predominante para o grupo CAD/CAM; os escores 1 e 2, para o grupo resina bisacrílica; e o escore 1, para o grupo resina acrílica. Conclusão: De forma geral, a resina bisacrílica apresentou os maiores valores de RC, seguida da resina acrílica e do material CAD/CAM, que apresentaram valores de RC inferiores à força recomendada para colagem de braquetes.

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Aim: To evaluate the retention of an endodontic titanium postwith a spherical head for removable partial denture or overdentureattachment according to surface treatment type. Methods: Sixtyhealthy single-rooted teeth, sectioned at the enamel/cementumjunction, were treated endodontically and steadily fixed in theembedding acrylic resin. The titanium posts were subdivided intofour groups: control, no surface treatment (Ctrl); posts with macroretentivegrooves (MR); air abrasion of the post surface (AB); andposts with macro-retentive grooves and air abrasion of the postsurface (MR+AB). The posts were luted in the root canal usingself-adhesive dual resin cement. Pull-out testing was performedusing a universal testing machine until complete detachment wasachieved. After pull-out testing, the metallic posts were examinedunder an optical microscope and the failures were classifiedbased on the cement distribution pattern on the extracted posts:0, no cement left on the post (cement/post failure); 1, postsurface partially covered by adhered cement (post/cement anddentin/cement mixed failure); 2, post surface completely coveredby cement (dentin/cement failure). The retention data wereanalyzed by one-way ANOVA, Bonferroni­Dunn test (p<0.05)and Weibull analysis. Results: AB showed the highest retentionvalue (485.37±68.36), followed by MR+AB (355.80±118.47), MR(224.63±42.54) and Ctrl (113.12 ± 51.32). AB and MR showedthe highest Weibull moduli. Conclusions: The data indicatedthat air abrasion alone could significantly increase the retentionof titanium posts/attachments for use with overdentures orremovable partial denture

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Abstract Objective This study aims to evaluate the influence of different air-abrasion pressures and subsequent heat treatment on the flexural strength, surface roughness, and crystallographic phases of highly translucent partially stabilized zirconia (Y-PSZ), and on the tensile bond strength of resin cement to Y-PSZ. Methodology Fully sintered zirconia specimens were ground with SiC paper (control) and/or air-abraded with 50 µm particles of alumina at 0.1, 0.15, 0.2, or 0.3 MPa or left as-sintered. After air-abrasion at 0.2 MPa (0.2AB), additional specimens were then heated to 1500°C, and held for one hour at this temperature (0.2AB+HT1h). Flexural strength and surface roughness were evaluated. Crystalline phase identification was also carried out using X-ray diffraction. Bonded zirconia specimens with self-adhesive resin cement were stored in distilled water at 37°C for 24 h, either with or without aging (thermal cycling 4-60°C/20000). Results were analyzed statistically by ANOVA and Tukey-Kramer tests. Results The flexural strength decreased with the increase in air-abrasion pressure, while in contrast, the surface roughness increased. The lowest flexural strength and the highest roughness value were found for the 0.2AB and 0.3AB groups, respectively. All groups contained cubic-, tetragonal ( t )-, and rhombohedral ( r )-ZrO2 phases with the exception of the as-sintered group. Upon increasing the air-abrasion pressure, the relative amount of the r -ZrO2 phase increased, with a significant amount of r -ZrO2 phase being detected for the 0.2AB and 0.3AB groups. The 0.2AB+HT1h group exhibited a similar flexural strength and t -ZrO2 phase content as the as-sintered group. However, the 0.2AB group showed a significantly higher tensile bond strength (p<0.05) than the 0.2AB+HT1h group before and after aging. Conclusion Micromechanical retention by alumina air-abrasion at 0.2 MPa, in combination with chemical bonding of a resin to highly translucent Y-PSZ using a MDP-containing resin cement may enable durable bonding.

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This study evaluated the influence of silica coating, primer type and its heat treatment on bond strength durability between resin cement and an yttrium-stabilized polycrystalline tetragonal zirconia (Y-TZP). Eighty (80) Y-TZP blocks were allocated into 16 groups considering four factors: silica coating (without and with); type of primer (RelyX Ceramic Primer, a silane-based primer; Single Bond Universal, a universal MDP-based primer); heat treatment of the primer (without and with); aging (without and with). After zirconia treatments, resin cement cylinders (RelyX ARC) (n = 20; N = 320) were built. Half of the samples were tested after 24 h, and another half were subjected to aging (thermocycling 5-55°C/5.000, and storage in water for 6 months). Shear bond strength test and failure analysis were performed. Bond strength data were submitted to four-way ANOVA and Tukey test (p = 0.05). All factors were statistically significant (p < 0.001) for bond strength (MPa): silica coating (7.3 ± 5.9) > no-treatment (3.6 ± 4.3); universal primer (6.7 ± 4.8) > silane (4.2 ± 5.8); heat-treatment (6.5 ± 6.3) > no-heating (4.4 ± 4.3); no-aging (8.2 ± 5) > aging (2.7 ± 4.4). Tukey test revealed that the association of silica coating + universal primer + heat-treatment promoted higher and stable resin bond strength. Silica coating, universal adhesive application and heat treatment improve/increase durability and bond strength of zirconia. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 104-111, 2019.

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Resumo Introdução A cimentação adesiva, com cerâmicas puras, é um passo relevante no estabelecimento da longevidade de trabalhos protéticos, sendo estes os melhores materiais utilizados para a reposição de dentes perdidos, de forma a reabilitar o sorriso. O sistema cerâmico de zircônia não se beneficia do tratamento com ácidos e necessita de diferentes métodos para tratar sua superfície, visando à efetividade na união adesiva. Objetivo Avaliar os resultados de diferentes técnicas de jateamento e aplicação de agente de união desenvolvidas para metais e cerâmica de zircônia (Ceramill ZI®), por meio de ensaio de tração, em dois diferentes tratamentos de superfície. Material e método Foram preparadas 20 amostras de Ceramill Zi® (n = 20), em forma de cilindro, e unidas entre si por meio do cimento resinoso (Multilink®), formando 10 espécimes (n = 10). Formaram-se sete grupos experimentais com os mesmos 10 espécimes e estes receberam dois tratamentos de superfície diferentes: abrasão e aplicação de agentes silânicos de união. Resultado A análise estatística mostrou diferenças significativas na resistência à fratura dos espécimes silicatizados com Rocatec®. Os valores de resistência de união à tração, mensurados em MPa, dos grupos 1 a 7, foram, respectivamente: 2,27; 4,48; 8,06; 8,32; 9,15; 10,56 e 10,70. As médias entre os grupos se apresentam estatisticamente significantes, exceto entre os grupos 3 e 4 e entre 6 e 7. Conclusão Os resultados mostraram que o tratamento da superfície cerâmica baseado no método de silicatização promoveu melhor união nos ensaios com Ceramill ZI® e cimentados com Multilink®.

Abstract Introduction Adhesive cementation, with pure ceramics, is a relevant step in establishing the longevity of prosthetic works. Being these, the best materials used for the replacement of lost teeth, in order to rehabilitate the smile. The ceramic zirconia system does not benefit from the treatment and planning needs for its surface, effectively in adhesive therapy. Objective Evaluate the results of different blasting techniques and application of bonding agent for metals and ceramics (Ceramill ZI®) by means of a tensile test in two different surface treatments. Material and method Twenty samples of Ceramill Zi® (n = 20), cylindrical and joined with resin cooling (Multilink®), were prepared, forming 10 specimens (n ​​= 10). The first 10 ingredients were formed by 7 experimental groups and they received 2 surface problems: abrasion and application of silane bonding agents. Result The research resulted in fracture resistance of Rocatec® silica specimens. The values ​​of tensile strength, measured in MPa, of groups 1 to 7, were: 2.27; 4.48; 8.06; 8.32; 9.15; 10.56 and 10.70. We observe how to enter the groups are statistically significant, except between groups 3 and 4 and between 6 and 7. Conclusion The results of the ceramic surface treatment were based on no silicate method, promoting the union of results with Ceramill ZI® and cemented with Multilink®.

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Abstract Objective This study aims to evaluate the effect of sonochemical treatment on the surface of yttria-stabilized tetragonal zirconia (Y-TZP) before and after the final sintering. Material and Methods Twenty-eight Y-TZP discs were divided into four groups (n=7), according to surface treatment: PRE: pre-sintering sonication with 30% nominal power for 15 min; POS: post-sintering sonication with 30% nominal power for 15 min; JAT: air abrasion with 50-μm alumina particles; and CON: control group with no treatment. The POS and JAT groups were sintered before sonication and the PRE group after sonication. Surface roughness was analyzed using confocal microscopy, after which resin cement cylinders were placed on the surface of the Y-TZP discs and subjected to mechanical microshear bond strength test until fracture. Surface roughness and microshear bond strength values underwent ANOVA and the Tukey tests. Results The surface roughness values for the PRE group (299.91 nm) and the POS group (291.23 nm) were not significantly different (p≥0.05), statistically, and the surface roughness value of the JAT group (925.21 nm) was higher than those of PRE and POS (p=0.007) groups. The mechanical microshear bond strength test showed that there was no statistically significant difference between the groups (p=0.08). Conclusions Therefore, the results showed that sonochemical treatment modifies the Y-TZP surface and is similar to the well-established sandblasting surface treatment regarding the strength of the bond with the resin cement.

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Introducción: La microabrasión se describe como un procedimiento realizado sobre el esmalte dental en el cual mediante la utilización de un agente ácido y un agente abrasivo se logra corregir alteraciones cromáticas superficiales. Algunos estudios demuestran como los parámetros de tiempo, número de aplicaciones y la presión ejercida, influyen en la can-tidad de esmalte eliminado. Objetivo: Establecer el espesor de esmalte dental eliminado según la capacidad abrasiva de 9 tratamientos químico mecánicos, mediante estereomicroscopia. Materiales y métodos: Con el aval del comité de ética de la Facultad de Odontología de la Universidad Nacional de Colombia, se recolectaron 90 terceros molares bajo consentimiento informado y se mantuvieron almacenados bajo los parámetros de la norma ISO 11405. Sobre bloques de acrílico se fijaron las mitades linguales de las coronas dentales, creando sobre ellas superficies planas mediante serie de lijas con irrigación y tomando impresiones con silicona de adición. Se distribuyeron de forma aleatoria en 9 grupos (n 10). Cada grupo recibió un tratamiento por un periodo de 30 segundos: G1: Opalustre® (Ultradent), G2: Piedra pómez y ácido fosfórico al 37% (Ultra-Etch®, Ultradent), G3: Piedra pómez, glicerina y ácido fosfórico al 37% (Ultra-Etch®, Ultradent), G4: Fresas de halo amarillo (Komet), G5: Fresas de halo blanco (Komet), G6: Discos Sof-Lex® (3M), color amarillo, G7: Discos Sof-Lex® (3M), color amarillo y amarillo claro, G8: Arenado, y G9: Puntas ultrasónicas Perfect Margin (Acteon). El espesor de desgaste creado fue medido utilizando un estéreo microscopio con un aumento de 10X. Los datos reco-lectados se analizaron a través de las pruebas de Kruskal-Wallis (p≤0.05) para comparar todos los grupos y la prueba U de Mann-Whitney (p≤0.05) para comparaciones individuales. Resultados: Independientemente del tratamiento realizado todos los grupos presentaron un desgaste del esmalte. El mayor desgaste se registró para el grupo tratado con fresa de halo amarillo (122,66 ± 22,64µm) y el menor desgaste para el grupo de arenado (11,5 ± 2,36µm). Se presentó diferencia estadísticamente significativa entre todos los grupos. Conclusiones: Bajo las limitaciones del presente estudio se puede concluir: La mayor microabrasión en esmalte se produjo con fresas de grano extrafino (halo amarillo) y el menor desgaste se produjo con arenado.

Introduction: Microabrasion is described as a procedure performed on tooth enamel in which the use of an acidic agent and an abrasive agent can correct surface chromatic alterations. Some studies show how the parameters of time, number of applications and the pressure exerted influence the amount of enamel removed.Objective: To establish the thickness of tooth enamel removed according to the abrasive capacity of 9 mechanical chemical treatments, using stereomicroscopy. Materials and methods: With the endorsement of the ethics committee of the School of Dentistry of the National University of Colombia, 90 third molars were collected under informed consent and kept stored under the parameters of ISO 11405. Acrylic blocks were fixed the lingual halves of the dental crowns, creating on them flat surfaces by means of series of sandpaper with irrigation and taking impressions with silicone of addition.They were distributed randomly in 9 groups (n 10). Each group was treated for a period of 30 seconds: G1: Opalustre® (Ultradent), G2: Pumice and 37% phosphoric acid (Ultra-Etch®, Ultradent), G3: Pumice, glycerin and phosphoric acid 37 % (Ultra-Etch®, Ultradent), G4: Yellow halo straw-berries (Komet), G5: White halo strawberries (Komet), G6: Sof-Lex® discs (3M), yellow color, G7: Sof-Lex discs ® (3M), yellow and light yellow, G8: Sandblasted, and G9: Perfect Margin ultrasonic tips (Acteon). The wear thickness created was measured using a stereo microscope with an increase of 10X. The collected data were analyzed through the Kruskal-Wallis tests (p≤0.05) to compare all groups and the Mann-Whitney U test (p≤0.05) for individual comparisons. Results: Regard-less of the treatment performed, all groups presented enamel wear. The highest wear was recorded for the group treated with yellow halo strawberry (122.66 ± 22.64µm) and the lowest wear for the sandblasting group (11.5 ± 2.36µm). There was a statistically significant difference between all groups. Conclusions: Under the limitations of the present study, it can be concluded: The greatest microabrasion in enamel was produced with strawberries of extra-fine grain (yellow halo) and the least wear occurred with sandblasting.

Introdução: A microabrasão do esmalte dental é descrita como um procedimento realizado no esmalte dentário, no qual o uso de um agente ácido e um abrasivo pode corrigir alterações cromáticas na superfície. Alguns estudos mos-tram como os parâmetros de tempo, número de aplicações e pressão exercida influenciam na quantidade do esmalte removido. Objetivo: Estabelecer a espessura do esmalte dentário removido de acordo com a capacidade abrasiva de 9 tratamentos químicos ou mecânicos, utilizando estereomicroscopia. Materiais e métodos: Com o aval do comitê de ética da Faculdade de Odontologia da Universidade Nacional da Colômbia, 90 terceiros molares hígidos foram coletados sob consentimento informado e mantidos armazenados sob os parâmetros da norma ISO 11405. Em blocos de acrílico foram fixadas as metades linguais das coroas dentárias, criando sobre elas superfícies planas por meio de séries de lixa mais irrigação e toma de impressões com silicone de adição. Eles foram distribuídos aleatoriamente em 9 grupos (n= 10). Cada grupo foi tratado por um período de 30 segundos: G1: Opalustre® (Ultradent), G2: Pedra-pomes e ácido fosfórico a 37% (Ultra-Etch®, Ultradent), G3: Pedra-pomes, glicerina e ácido fosfórico 37 % (Ultra-Etch®, Ultradent), G4: brocas diaman-tadas halo amarelo (Komet), G5: brocas diamantadas halo branco (Komet), G6: discos Sof-Lex® (3M), cor amarelo, G7: discos Sof-Lex ® (3M), amarelo e amarelo claro, G8: jateamento e G9: pontas ultra-sônicas Perfect Margin® (Acteon). A espessura de desgaste criada foi medida usando um microscópio estéreo com um aumento de 10X. Os dados coletados foram analisados pelos testes de Kruskal-Wallis (p≤0,05) para comparar todos os grupos e pelo teste U de Mann-Whit-ney (p≤0,05) para comparações individuais. Resultados: Independentemente do tratamento realizado, todos os grupos apresentaram desgaste do esmalte. O maior desgaste foi registrado para o grupo tratado com broca diamantada com halo amarelo (122,66 ± 22,64 µm) e o menor desgaste para o grupo de jateamento (11,5 ± 2,36 µm). Houve diferença estatisticamente significante entre todos os grupos. Conclusões: Sob as limitações do presente estudo, pode-se concluir que a maior microabrasão no esmalte foi produzida com brocas de grão extra-fino (halo amarelo) e o menor desgaste ocorreu com o jateamento.

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Abstract Objectives: To evaluate the effects of dentin pretreatment and temperature on the bond strength of a universal adhesive system to dentin. Material and Methods: Ninety-six extracted non-carious human third molars were randomly divided into 12 groups (n=8) according to Scotchbond Universal Adhesive (SbU) applied in self-etch (SE) and etch-and-rinse (ER) mode, adhesive temperature (20°C or 37°C) and sodium bicarbonate or aluminum oxide air abrasion. After composite build up, bonded sticks with cross-sectional area of 1 mm2 were obtained to evaluate the microtensile bond strength (μTBS). The specimens were tested at a crosshead speed of 0.5 mm/min on a testing machine until failure. Fractured specimens were analyzed under stereomicroscope to determine the failure patterns in adhesive, cohesive (dentin or resin) and mixed fractures. The microtensile bond strength data was analyzed using two-way ANOVA and Tukey's test (α=5%). Results: Interaction between treatment and temperature was statistically significant for SbU applied in self-etch technique. Both dentin treatments showed higher bond strength for ER mode, regardless of adhesive temperature. When compared to control group, sodium bicarbonate increased bond strength of SbU in SE technique. Adhesive temperature did not significantly affect the μTBS of tested groups. Predominantly, adhesive failure was observed for all groups. Conclusions: Dentin surface treatment with sodium bicarbonate air abrasion improves bond strength of SbU, irrespective of adhesive application mode, which makes this approach an alternative to increase adhesive performance of Scotchbond Universal Adhesive to dentin.

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Abstract This study evaluated the effect of air-abrasion on t®m phase transformation, roughness, topography and the elemental composition of three Y-TZP (Yttria-stabilized tetragonal zirconia polycrystal) dental ceramics: two conventional (Lava Frame and IPS ZirCad) and one with high-translucency (Lava Plus). Plates obtained from sintered blocks of each ceramic were divided into four groups: AS (as-sintered); 30 (air-abrasion with 30 mm Si-coated Al2O3 particles); 50 (air-abrasion with 50 mm Al2O3 particles) and 150 (air-abrasion with 150 mm Al2O3 particles). After the treatments, the plates were submitted to X-ray diffractometry; 3-D profilometry and SEM/EDS. The AS surfaces were composed of Zr and t phases. All treatments produced t®m phase transformation in the ceramics. The diameter of air-abrasion particles influenced the roughness (150>50>30>AS) and the topography. SEM analysis showed that the three treatments produced groove-shaped microretentions on the ceramic surfaces, which increased with the diameter of air-abrasion particles. EDS showed a decrease in Zr content along with the emergence of O and Al elements after air-abrasion. Presence of Si was also detected on the plates air-abraded with 30 mm Si-coated Al2O3 particles. It was concluded that irrespective of the type and diameter of the particles, air-abrasion produced t®m phase transformation, increased the roughness and changed the elemental composition of the three Y-TZP dental ceramics. Lava Plus also behaved similarly to the conventional Y-TZP ceramics, indicating that this high translucency ceramic could be more suitable to build monolithic ceramic restorations in the aesthetic restorative dentistry field.

Resumo Este estudo avaliou o efeito da abrasão a ar na transformação de fase t®m, na rugosidade, topografia e composição elementar de três cerâmicas Y-TZP (Zircônia tetragonal policristalina estabilizada por ítrio): duas convencionais (Lava Frame e ZirCad) e uma de alta translucidez (Lava Plus). Placas obtidas de blocos sinterizados de cada cerâmica foram divididos em quatro grupos: AS (pré-sinterizado); 30 (jateamento com partículas de Al2O3 de 30 mm cobertas com Si); 50 (jateamento com partículas de Al2O3 de 50 mm) e 150 (jateamento com partículas de Al2O3 de 150 mm). Após os tratamentos, as placas foram submetidas à difratometria de Rx, perfilometria 3-D e microscopia eletrônica de varredura com espectroscopia de energia dispersiva de Rx (SEM/EDS). As superfícies pré-sinterizadas apresentaram predominantemente Zr e fase tetragonal. Todos os tratamentos superficiais produziram transformação t®m nas cerâmicas avaliadas. A topografia e a rugosidade foram influenciadas pelo diâmetro das partículas abrasivas (150>50>30>AS). A análise através de SEM mostrou que os três tratamentos produziram fendas retentivas nas superfícies das cerâmicas, por influência do tamanho das partículas. A análise através de EDS mostrou uma diminuição da concentração de Zr, paralela ao surgimento de O e Al, após o jateamento. No grupo tratado com partículas de Al2O3 de 30 mm cobertas com Si foi também observado um aumento de Si após o jateamento. Concluiu-se que, independente do tipo e do diâmetro das partículas, o jateamento produziu transformação t®m, aumentou a rugosidade e alterou a composição elementar das cerâmicas avaliadas. A Lava Plus apresentou comportamento semelhante às cerâmicas convencionais, indicando que esta cerâmica de alta translucidez pode ser mais adequada à confecção de restaurações monolíticas no campo da odontologia estética restauradora.

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Introdução: Os pinos de fibra de vidro são uma alternativa aos núcleos metálicos e apresentam vantagens, tais como: estética, módulo de elasticidade semelhante à dentina e cimentação imediata após o término do tratamento endodôntico. Ainda, apresentam a capacidade de aderir ao cimento resinoso e este, à dentina, por meio de técnicas adesivas. Objetivo: Comparar a adesão de um cimento resinoso convencional e um autoadesivo a pinos de fibra de vidro, e os efeitos de diferentes tratamentos de superfície na resistência adesiva dos pinos. Material e método: Trinta pinos foram divididos em três grupos: Controle: sem tratamento na superfície; Jateamento: jateamento com óxido de alumínio por 30 segundos, e Peróxido: imersão em peróxido de hidrogênio 24% por um minuto. Em seguida, corpos de prova foram obtidos a partir de cilindros de cimento resinoso contendo o pino de fibra posicionado no centro de seu longo eixo. Em cada grupo, cinco pinos foram associados ao adesivo Âmbar + cimento convencional AllCem Core e os outros cinco pinos, ao cimento autoadesivo RelyX U200. O conjunto pino/cimento foi segmentado e avaliado em relação à resistência de união (RU) por push-out. Os dados foram analisados estatisticamente pelos testes de ANOVA e Tukey (p< 0,05). Resultado: Os cimentos avaliados exibiram valores de RU semelhantes. Em relação aos tratamentos de superfície, os maiores valores de RU foram encontrados no grupo Jateamento. Conclusão: O cimento convencional, AllCem Core, e o cimento autoadesivo, RelyX U200, mostraram valores de resistência de união semelhantes. Ainda, o jateamento com óxido de alumínio favoreceu a adesão dos pinos aos cimentos.

Introduction: The fiberglass posts are an alternative to the metal cast, presenting some advantages, such as aesthetics, tensile modulus similar to dentin and can be placed in a single session, immediately after the endodontic treatment. It also has the ability to adhere to the resin cement and the last to dentin by means of bonding techniques. Objective: To compare the adhesion of a conventional resin cement with a self-adhesive to fiberglass posts, and the effects of different surface treatments on adhesion of posts. Material and method: Thirty fiber posts were divided into 3 groups: control: untreated surface; Blasting: blasting with aluminum oxide for 30 seconds and peroxide: immersion in 24% hydrogen peroxide for 1 minute. Then, the samples were obtained from resin cement cylinders containing the fiber post positioned in the center of its long axis. In each group 5 posts were associated with the adhesive Ambar+conventional cement Allcem Core and the other 5 posts with the self-adhesive cement RelyX U200. The post/cement sample was segment in discs and evaluated for bond strength (BS) by push-out test. Data were analyzed statistically by ANOVA and Tukey tests (p< 0.05). Result: The cements evaluated exhibited similar BS values. Regarding surface treatments, the highest BS values were found in blasting group. Conclusion: Conventional cement, Allcem Core, and self-adhesive, RelyX U200, showed similar bond strength values. Also, blasting with aluminum oxide favored the adhesion of posts to cements.

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Problematização. As Zircônias tetragonais estabilizadas com ítria (Y-TZP) são amplamente utilizadas na confecção de próteses dentárias. Uma vez que é mais utilizada como infraestrutura, as cerâmicas de cobertura ainda mostram fraturas, resultando em redução da longevidade da prótese. Objetivo. Avaliar e testar a eficácia de tratamentos de superfície entre Y-TZP e cerâmica de cobertura antes da aplicação do liner. Material e métodos. Quarenta discos Y-TZP (12,5mm de diâmetro e 3,5mm de espessura) foram divididos em quatro grupos (n = 10): LC: aplicação exclusiva do liner; S40: sonicação pré-sinterizada com 40 % de potência nominal durante 15 minutos; S70: sonicação présinterizada com 70 % de potência nominal durante 15 minutos; JOX: jateamento com partículas de alumínio de 50µm. Após os tratamentos rugosos de superfície, o liner foi aplicado na superfície das amostras todos os grupos. Após a sinterização, os espécimes foram submetidos a Microscopia confocal de varredura a laser (CLSM) e Microscopia de força atômica (AFM) para avaliar a topografia e a rugosidade da superfície. As fases das estruturas cristalinas foram identificadas através de espectroscopia micro-Raman (MRS). Após esta etapa, a cerâmica de cobertura foi aplicada em todas as superfícies da Y-TZP e os espécimes foram submetidos ao teste de Resistência de união ao cisalhamento (SBS) a uma velocidade de 0,5mm/min até à fratura. Os modos de falha foram classificados como adesiva, coesiva ou mista. Os resultados de SBS foram submetidos a uma ANOVA a um critério (α = 0,05) seguido pelo teste de Tukey (α = 0,05). Resultados. Não foram observadas diferenças entre os grupos quanto à rugosidade superficial (0,255), embora as imagens da Microscopia Confocal e AFM apresentassem diferenças topográficas entre os grupos. O grupo LC apresentou maiores valores medianos de SBS, significativamente diferentes de S70 e JOX (p=0,008), os quais não foram diferentes. S40 apresentou os valores medianos de SBS mais baixos (15,43 Mpa). Todos os espécimes Y-TZP exibiram bandas típicas tetragonais e fases monoclínicas. A maioria dos espécimes de todos os grupos exibiram falhas mistas (67,5%) e os espécimes restantes exibiram falhas adesivas. Conclusão. Tratamentos de superfície adicionais para Y-TZP, jateamento e tratamento sonoquímico com potência de 70 % mostraram resultados semelhantes, mas não aumentaram a SBS para uma cerâmica de cobertura.(AU)

Statement of the problem. The yttria-stabilized tetragonal zirconia (Y-TZP) ceramics are widely used manufacturing of dental prostheses. Since it is most used as framework, the ceramics veneers still show fractures, resulting in reduction of longevity of the prosthesis. Objective. Evaluate and test the effectiveness of roughening treatments between Y-TZP and veneering ceramic before liner application. Material and methods. Forty Y-TZP discs (12.5mm Ø and 3.5mm thickness) were divided in four groups (n = 10): LC: application of the proprietary liner only; S40: pre-sintered sonication with 40 % nominal power for 15 minutes; S70: pre-sintered sonication with 70 % nominal power for 15 minutes; JOX: sandblasting with 50 µm aluminum particles. After roughening treatments, the liner was applied to the surface of the samples in all groups. After sintering, the specimens were subjected to confocal laser scanning microscopy (CLSM) and atomic force microscopy (AFM) analyses to evaluate the topography and surface roughness. The phases of the crystalline structures were identified through micro-Raman spectroscopy (MRS). After that, a veneering ceramic was applied to all Y-TZP surfaces and subjected to shear bond strength (SBS) testing at a speed of 0,5mm/min until fracture. Failure modes were classified as adhesive, cohesive, or mixed. SBS results were subjected to one-way ANOVA (α = 0.05) followed by Tukey's test (α = 0.05). Results. No differences were shown between groups regarding surface roughness (p=0,255), although Confocal and AFM images showed topographical differences among groups. The LC group showed the highest SBS median values, which were significantly different from S70 and JOX (p=0,008), which were not different. S40 showed the lowest SBS median values (15,43 MPa). All specimens exhibited typical Y-TZP tetragonal bands and monoclinic phases. Most specimens of all groups exhibited mixed failures (67,5%) and the remaining specimens exhibited adhesive failures. Conclusion. Additional surface treatments for Y-TZP, sandblasting, and 70 % power sonochemical treatment showed similar results but did not increase SBS to a feldspathic ceramic.(AU)

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To evaluate the shear bond strength of a recent adhesive system used in the cementation of zirconia.Material and Methods:Overall, 72 zirconia specimens (Zirconzhan) were divided and randomized into 3 groups according to the type of surface treatment: G1 no treatment + adhesive system; G2 blasted with aluminum oxide + adhesive system and G3 tribochemical treatment (Rocatec Plus) + adhesive system. Half of each group (n = 12) had bond strength evaluated on two occasions: 24 hours after cementation, kept stored in distilled water at 37 ° C without thermal cycling, and after thermal cycling (5000 cycles, 5°C-55°C). Data were analyzed by ANOVA with Tukey's post-test (α≤0.05).Results:At first moment, G1 and G3 showed higher bond strength (8.64 ± 3.43 MPa and 6.55 ± 2.27 MPa) compared to G2, with no statistically significant difference between them. After thermal cycling, G3 showed higher bond strength (7.70 ± 1.82 MPa).Conclusion:Initially, only the adhesive system promoted higher bond strength, but after thermal cycling,bond strength decreased. The best treatment to promote high bond strength to zirconia is to associate tribochemical treatment with the adhesive system; most failures observed after thermal cycling were mixed and cohesive, showing a mechanical imbrication of the adhesive system, suggesting that there is no chemical bond; and the surface of the group with greater bond strength after thermal cycling showed more surface irregularities compared to the other groups...

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OBJECTIVES: To investigate the adhesive potential of novel zirconia primers and universal adhesives to surface-treated zirconia substrates. METHODS: Zirconia bars were manufactured (3.0mm×3.0mm×9.0mm) and treated as follows: no treatment (C); air abrasion with 35µm alumina particles (S); air abrasion with 30µm silica particles using one of two systems (Rocatec or SilJet) and; glazing (G). Groups C and S were subsequentially treated with one of the following primers or adhesives: ZP (Z-Prime Plus), AZ (AZ Primer); MP (Monobond Plus); SU (ScotchBond Universal) and; EA (an Experimental Adhesive). Groups Rocatec and SilJet were silanized prior to cementation. Samples form group G were further etched and silanized. Bars were cemented (Multilink) onto bars of a silicate-based ceramic (3.0mm×3.0mm×9.0mm) at 90° angle, thermocycled (2.500 cycles, 5-55°C, 30s dwell time), and tested in tensile strength test. Failure analysis was performed on fractured specimens to measure the bonding area and crack origin. RESULTS: Specimens from group C did not survive thermocycling, while CMP, CSU and CEA groups survived thermocycling but rendered low values of bond strength. All primers presented a better bond performance after air abrasion with Al2O3 particles. SilJet was similar to Rocatec, both presenting the best bond strength results, along with SMP, SSU and CEA. G promoted intermediate bond strength values. Failure mode was predominately adhesive on zirconia surface combined to cohesive of the luting agent. CONCLUSIONS: Universal adhesives (MP, SU, EA) may be a considerable alternative for bonding to zirconia, but air abrasion is still previously required. Air abrasion with silica particles followed by silane application also presented high bond strength values.

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Objetive: The purpose of this study was to evaluate the influence of sandblasting distance on ceramic and enamelbond strength. Material & Methods: Sixtythird molars were selected, enamel surfaces were ground flat with wet 600 - 2000 grit aluminum oxide abrasive papers and polished with three, one, and one-fourth micrometer-grit diamond pastes. On hundred and twentylithium disilicate-based core ceramic discs (2 mm diameter; 1 mm thickness) were also obtained and further divided into 7 groups [Group C, no sandblasting, Group SB-E(5-10) enamel sandblasting - 5 and 10 mm of distance, Group SBC(5-10) ceramic sandblasting 5 mm and 10 mm of distance, Group SB-EC(5-10) enamel and ceramic sandblasting 5 mm and 10 mm of distance]. After treatments,shear and Atomic Force Microscopy (AFM) tests were performed.Data were analyzed by Statistic Tests of normality, one-way ANOVA and Tukey post-test (α: 0.05). Results: Group C presented the highestbond strength values(59.2 ±12.5), while group SB-E 5 mm showed the lowest values (21.7 ± 08.8) (p < 0.005). Conclusion: The use of sandblasting treatment of enamel surface at 5mm distance decreases the bonding strength to shear.

Objetivo: o objetivo do estudo foi avaliar influência do jateamento na estrutura cerâmica e esmalte sob resistência de união, mudando a distância. Materiais e Métodos: 60 terceiros molares, foram selecionados, superfícies de esmalte foram planificadas com lixa com grão 600 - 2000 lixas e polido com pastas de diamante de um grão -micrômetro. Obtidos 120 discos cerâmica em dissilicato de lítio de (2 mm de diâmetro e 1 mm de espessura), dividido em sete grupos [Grupo C, não jateamento, Grupo SB-E (5-10) esmalte jateamento 5 e 10 mm, Grupo SB -C (5-10) de jacto de areia cerâmica 5 mm e 10 mm, Grupo SB-CE (5-10) e esmalte cerâmico areação 5 milímetros e 10 mm], depois foi realizado o microcisalhamento e a microscopia de forca atômica (AFM), estatística como Teste de Normalidade , após análise de variância one-way e teste de Tukey (α: 0,05). Resultados: A força do grupo C apresentou maiores valores de resistência de união (59,2 ± 12,5), o grupo SB-E 5 mm (21,7 ± 08,8) (p < 0,005), o grupo SB-E10 (53,6 ± 14,3). Conclusão: o uso de jateamento tratamento da superfície do esmalte de 5 mm, de 20 s diminui a força de ligação de microcisalhamento.

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