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PURPOSE: To evaluate the effect of different surface treatments and adhesive cementation on the miniflexural strength (MFS) of monolithic zirconia. MATERIALS AND METHODS: Two-hundred and forty (240) sintered bars of translucent zirconia (ZT) and ultra-translucent zirconia (ZUT) were obtained (8 mm ×2 mm ×1 mm). The bars were divided into 16 groups (n = 15) according to the factors "Zirconia" (ZT and ZUT), "Cementation" (Cem) and "surface treatment" (Ctrl:Control, Al:Aluminum oxide/Al2O3 50 µm, Si:Silica/SiO2 coated alumina particles oxide 30 µm, Gl:Glazing+hydrofluoric acid). Half of the bars received an adhesive layer application, followed by application of resin cement and light curing. The surface roughness was measured in non-cemented groups. All the bars were subjected to the MFS test (1.0 mm/min; 100 kgf). Scanning electron microscopy was used for qualitative analyses. MFS data (MPa) and roughness (µm) were statistically evaluated by three-way and two-way ANOVA respectively and Tukey's test (5%). RESULTS: The surface treatment and the interaction were significant for roughness. Glazing promoted less roughness compared to silicatization. Regarding MFS, only the zirconia and surface treatment factors were significant. For ZT, the sandblasted groups had an increase in MFS and glazing reduced it. There was no difference between the groups without cementation for the ZUT; however, ZUT.Si/Cem, and ZUT.Al/Cem obtained superior MFS among the cemented groups. CONCLUSIONS: Sandblasting increases the flexural strength for ZT, while glaze application tends to reduce it. Applying resin cement increases the flexural strength of ZUT when associated with sandblasting. Sandblasting protocols promote greater surface roughness.

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The objective is to evaluate the effect of different surface treatments and storage on the shear strength of ultratranslucent zirconia. 36 blocks of ultra-translucent zirconia were fabricated (7x7x2mm) and sintered. Then, divided into 12 groups according to the "surface treatment" (C -Primer; Al -Sandblasting with Al2O3 + Primer; Si -Silicate + Primer; Gl -Glaze + HF + Primer; Z -Zirlink; Zp -Zirlink + Primer) and "storage" factors (ST-with 150 days/37º and without). After surface treatment, five cylinders (Ø=2mm; h=2.0mm) of resin cement (n=15) were constructed in each ceramic block; at the end, the shear strength test was performed (1mm/min, 50Kgf), and analysis of surface failures. 60 additional samples (2x2x2mm) were made for extras analysis (surface roughness, MEV, and EDS). Bond strength and surface roughness data were statistically evaluated by ANOVA (2 factors/1 factor), Tukey test (5%), and Weibull analysis, respectively. ANOVA (2-way) revealed that all factors were statistically significant for bond strength. The silicatization groups (SiST: 30.47AMPa; Si: 29.21AMPa) showed the highest bond strength values, regardless of storage (Tukey's test). While the groups treated with Zirlink (ZST: 2.76FMPa; Z: 5.27EFMPa) showed the lowest values, just similar to the GlST group (5.14EFMPa). The Weibull modulus (m) showed a statistical difference between groups (p=0.000). ANOVA (1 factor) revealed that the "surface treatment" factor (p=0.0000) was statistically significant for surface roughness. Therefore, the application of Zirlink and Glaze on pre-sintered zirconia did not promote efficient adhesion of the ultratranslucent zirconia to the resin cement, even when associated with a primer containing MDP.

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Abstract The objective is to evaluate the effect of different surface treatments and storage on the shear strength of ultratranslucent zirconia. 36 blocks of ultra-translucent zirconia were fabricated (7x7x2mm) and sintered. Then, divided into 12 groups according to the "surface treatment" (C -Primer; Al -Sandblasting with Al2O3 + Primer; Si -Silicate + Primer; Gl -Glaze + HF + Primer; Z -Zirlink; Zp -Zirlink + Primer) and "storage" factors (ST-with 150 days/37º and without). After surface treatment, five cylinders (Ø=2mm; h=2.0mm) of resin cement (n=15) were constructed in each ceramic block; at the end, the shear strength test was performed (1mm/min, 50Kgf), and analysis of surface failures. 60 additional samples (2x2x2mm) were made for extras analysis (surface roughness, MEV, and EDS). Bond strength and surface roughness data were statistically evaluated by ANOVA (2 factors/1 factor), Tukey test (5%), and Weibull analysis, respectively. ANOVA (2-way) revealed that all factors were statistically significant for bond strength. The silicatization groups (SiST: 30.47AMPa; Si: 29.21AMPa) showed the highest bond strength values, regardless of storage (Tukey's test). While the groups treated with Zirlink (ZST: 2.76FMPa; Z: 5.27EFMPa) showed the lowest values, just similar to the GlST group (5.14EFMPa). The Weibull modulus (m) showed a statistical difference between groups (p=0.000). ANOVA (1 factor) revealed that the "surface treatment" factor (p=0.0000) was statistically significant for surface roughness. Therefore, the application of Zirlink and Glaze on pre-sintered zirconia did not promote efficient adhesion of the ultratranslucent zirconia to the resin cement, even when associated with a primer containing MDP.

Resumo O objetivo é avaliar o efeito de diferentes tratamentos superficiais e do envelhecimento na resistência ao cisalhamento da zircônia ultratranslúcida. Foram confeccionados 36 blocos de zircônia ultratranslúcida (7x7x2mm) e sinterizados. Em seguida, divididos em 12 grupos de acordo com o "tratamento de superfície" (C-Primer; Al-Jateamento com Al2O3+Primer; Si-Silicato+Primer; Gl -Glaze+HF+Primer; Z-Zirlink; Zp-Zirlink+Primer) e fatores de "armazenamento" (ST-com, 150 dias/37º e sem). Após o tratamento superficial, foram construídos cinco cilindros (Ø=2mm; h=2,0mm) de cimento resinoso (n=15) em cada bloco cerâmico; ao final foi realizado o ensaio de resistência ao cisalhamento (1mm/min, 50Kgf) e análise de falhas superficiais. Foram confeccionadas 60 amostras adicionais (2x2x2mm) para análises extras (rugosidade superficial, MEV e EDS). Os dados de resistência de união e rugosidade superficial foram avaliados estatisticamente por ANOVA (2 fatores/1fator), teste de Tukey (5%) e análise de Weibull, respectivamente. ANOVA (2 fatores) revelou que todos os fatores foram estatisticamente significativos para a resistência de união. Os grupos de silicatização (SiST: 30,47AMPa; Si: 29,21AMPa) apresentaram os maiores valores de resistência de união, independente do armazenamento (Tukey). Enquanto os grupos tratados com Zirlink (ZST: 2,76FMPa; Z: 5,27EFMPa) apresentaram os valores mais baixos, apenas semelhantes ao grupo GlST (5,14EFMPa). O módulo de Weibull (m) apresentou diferença estatística entre os grupos (p=0,000). A ANOVA (1 fator) revelou que o fator "tratamento superficial" (p=0,0000) foi estatisticamente significativo para rugosidade superficial. Portanto, a aplicação de Zirlink e do Glaze na zircônia pré-sinterizada não promoveu adesão eficiente da zircônia ultratranslúcida ao cimento resinoso, mesmo quando associada a primer contendo MDP.

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In the RLT (Rapid Layer Technology), veneering ceramic and framework are fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM) and then cemented to obtain the restoration. This study aimed to evaluate the effect of the thickness of veneering ceramic manufactured by the RLT technique on the fracture resistance (FR) of bilayer crowns with zirconia frameworks. Twenty zirconia frameworks and twenty feldspathic posterior crowns with two different veneering ceramic occlusal thicknesses (1mm=TF1; 2mm=TF2) were manufactured using CAD/CAM system. The specimens were luted to an epoxy resin abutment with resin cement and mechanically cycled (200N and 4.5×105 Pa, 37°C, 2×106 cycles, 3Hz). The FR test was performed (10kN, 0.5mm/min), and the specimens were analyzed in a stereomicroscope. For the stress analysis (finite element analysis, FEA), a 10kN load was equal to the in vitro test, and the principal stress was evaluated. The FR data were analyzed by Student's t-test and Weibull's analysis. The thickness influenced the FR of bilayer crowns. The FR was higher in the TF2 than in the TF1 group. The TF2 group presented the highest characteristic strength compared to the group TF1. The predominant type of failure was delamination. The FEA showed higher stress concentrations below the loading application point at the veneering cement interface in the 1-mm-thick model. The bilayer crowns manufactured using the approach of 2mm of veneering ceramic promoted higher FR compared to the group with 1mm veneering ceramic. Also, the FEA showed that the veneer ceramic thickness has an effect on stress distribution in zirconia-based bilayer crowns.

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Abstract In the RLT (Rapid Layer Technology), veneering ceramic and framework are fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM) and then cemented to obtain the restoration. This study aimed to evaluate the effect of the thickness of veneering ceramic manufactured by the RLT technique on the fracture resistance (FR) of bilayer crowns with zirconia frameworks. Twenty zirconia frameworks and twenty feldspathic posterior crowns with two different veneering ceramic occlusal thicknesses (1mm=TF1; 2mm=TF2) were manufactured using CAD/CAM system. The specimens were luted to an epoxy resin abutment with resin cement and mechanically cycled (200N and 4.5×105 Pa, 37°C, 2×106 cycles, 3Hz). The FR test was performed (10kN, 0.5mm/min), and the specimens were analyzed in a stereomicroscope. For the stress analysis (finite element analysis, FEA), a 10kN load was equal to the in vitro test, and the principal stress was evaluated. The FR data were analyzed by Student's t-test and Weibull's analysis. The thickness influenced the FR of bilayer crowns. The FR was higher in the TF2 than in the TF1 group. The TF2 group presented the highest characteristic strength compared to the group TF1. The predominant type of failure was delamination. The FEA showed higher stress concentrations below the loading application point at the veneering cement interface in the 1-mm-thick model. The bilayer crowns manufactured using the approach of 2mm of veneering ceramic promoted higher FR compared to the group with 1mm veneering ceramic. Also, the FEA showed that the veneer ceramic thickness has an effect on stress distribution in zirconia-based bilayer crowns.

Resumo Na RLT (Rapid Layer Technology), a cerâmica de cobertura e infraestrutura são fabricados pelo Computer-Aided Design / Computer-Aided Manufacturing (CAD / CAM) e cimentados para obter a restauração. Este estudo teve como objetivo avaliar o efeito da espessura da cerâmica de cobertura fabricada pela técnica RLT na resistência à fratura (RF) de coroas bilaminadas com infraestrutura de zircônia. Vinte infraestruturas de zircônia e vinte coroas posteriores feldspáticas com duas espessuras oclusais da cerâmica de cobertura (1mm = TF1; 2mm = TF2) foram fabricadas usando o sistema CAD / CAM. Os espécimes foram cimentados em preparos de resina epóxi com cimento resinoso dual e ciclados mecanicamente (200N e 4,5×105 Pa, 37° C, 2×106 ciclos, 3Hz). O teste de RF foi realizado (10kN, 0,5mm / min) e, posteriormente, os espécimes foram analisados em estereomicroscópio. Para a análise de tensão (análise de elementos finitos, FEA), uma carga de 10kN foi aplicada igual ao teste in vitro, e a tensão principal foi avaliada. Os dados de RF foram analisados pelo teste t de Student e análise de Weibull. A espessura mostrou forte influência na RF das coroas bilaminadas. A RF foi maior em TF2 do que no grupo TF1. O grupo TF2 apresentou a maior resistência característica em relação ao grupo TF1. O tipo de falha predominante foi a delaminação. O FEA mostrou maiores concentrações de tensões abaixo do ponto de aplicação da carga, na interface cimento e cerâmica de cobertura no modelo de coroa de 1 mm de espessura. As coroas de bilaminadas confeccionadas com 2 mm de cerâmica de cobertura promoveram maior RF em comparação ao grupo com cerâmica de cobertura de 1 mm. Além disso, a FEA mostrou que a espessura da cerâmica de cobertura tem um efeito na distribuição de tensões em coroas bilaminadas à base de zircônia.

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BACKGROUND: To evaluate, in vitro, the effects of the cooling protocol, application technique, and veneering ceramic thickness on the fracture resistance of ceramic crowns with Y-TZP frameworks. MATERIAL AND METHODS: 80 frameworks were made from zirconia by the CAD/CAM technique and divided into 8 groups (n = 10) according to the factors: "application technique" (stratified-L and pressed -P), "thickness" (1 mm and 2 mm), and "cooling protocol" (slow-S and fast-F) of the feldspathic veneering ceramic. After, all crowns were cemented over G10 preparations with resin cement (Panavia F, Kuraray), mechanically cycled (2x106 cycles, 200 N, 3Hz), and subjected to the axial compression resistance test (0.5 mm/min, 10 kN). The data (N) underwent descriptive statistical analysis by 3-way ANOVA and Tukey's test (5%). Fracture analysis was performed to determine the possible origin of failure. RESULTS: The factors "cooling protocol" (P=0.0058) and "application" technique (P=0.0001) influenced the fracture resistance of the crowns. For pressed veneer technique, the P2S (4608.9±464.5). A presented significantly higher results than that P2F(3621.1±523.0)BCD (Tukey's test). For the stratified technique, this difference was not observed (P>0.05). The thickness of the veneering ceramic was not significant regardless of the cooling protocol and technique (P>0.05). The predominant failure mode was chipping of the ceramic veneer originating in the subsurface. CONCLUSIONS: The pressed technique, used with a slow-cooling protocol, leads to the best outcome for the veneering of all-ceramic crowns. Key words:Zirconia, ceramics, cooling protocol, thickness, application technique.

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OBJECTIVE: To evaluate the influence of extrinsic pigmentation on the biaxial flexural strength and surface topographic of translucent Y-TZP (InCoris TZI - Sirona - USA) subjected to several surface treatments. METHODS: Sintered zirconia discs-shaped specimens (n=120) (ø:12mm; thickness:1.2mm; ISO 6872) were prepared and divided (n=15) according to various factors: "extrinsic pigmentation" (n: without; p: with) and "surface treatments" (C: control - as sintered; A: abraded with silica-coated alumina particles (30µm); G: glazed with a thin film of low-fusing porcelain glaze; GH: glazed and etched with 10% hydrofluoridric acid for 60s. Mechanical cycling (1.2×106 cycles, 200N, 3.8Hz) and flexural strength test (1mm/min - 1000kg cell) were performed. Two-way ANOVA and Tukey's were used for statistical test (α=0.05). Weibull analysis was used to evaluate the strength reliability. Samples were analyzed via (1) an optical profilometer to determine the surface roughness (Ra); (2) an X-ray diffraction (XRD) to evaluate phase transformations; and (3) a SEM equipped with an energy dispersive X-ray spectroscopy (EDX) to elucidate morphological properties and chemical compositions. RESULTS: Regardless of the surface treatment (p=0.5459) (Cn: 560.16MPa; Gn: 573.36MPa; An: 643.51MPa; GHn: 542.94MPa; Cp: 628.04MPa; Gp: 641.90MPa; Ap: 554.47MPa; GHp :602.84MPa) and extrinsic pigmentation (p=0.1280) there was no difference in the flexural strength among the experimental groups. According to the XRD analysis, phase transformations occurred in the An group (t→m) and in Ap group (t→c). Surface roughness was affected by surface treatments (An - p=0.001) and extrinsic pigmentation (Gp - p=0.001). SIGNIFICANCE: The biaxial flexural strength of the tested samples was not affected neither by surface treatments nor by pigmentation, although it can cause phase transformation and promote surface roughness.

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Aim: evaluate the influence of etching time with hydrofluoric acid on the bond strength of a Yttrium-stabilized polycrystalline tetragonal zirconia (Y-TZP) ceramic with a superficial glaze layer and a resin cement. Methods: Y-TZP blocks were cut to obtain 40 samples. They were distributed into four groups (n = 10): control treated by sandblasting with silica-coated alumina (RS) and three glazed experimental groups with different etching times: GS20s, GS60s and GS100s. Cementation was done with a universal adhesive and a resin cement. Two cement cylinders were made in each block. After thermocycling, the shear bond test was performed. Two extra samples of each group were made to obtain profilometry, scanning electron microscopy, mapping and backscattered electron detector images. Energy dispersive spectrometry and goniometry were also performed. Results: Kruskal-Wallis and Dunn tests demonstrated bond strength differences only between the RS (22.10MPa) and the GS groups (GS20s: 8,10Mpa; GS60s: 10.49MPa; GS100s: 7.53MPa) (p = 0.001), but there was no difference among the experimental groups (p > 0.05). The contact angles were 55.33º (RS); 70.78° (GS100s); 48.20º (GS60s) and 28.73º (GS20s). ANOVA and Tukey test demonstrated similar wettability of RS to GS60s and GS100s (p > 0.05), but all the experimental groups were statistically different between them (p < 0.001). Qualitative image analysis revealed an irregular glaze distribution after etching. The thickness of the remaining glaze layer measured by profilometry was 5±1µm (GS20S), 4±1µm (GS60S) and 3±1µm (GS100s). Conclusion: The etching time of glazed zirconia did not influence the adhesive strength of the ceramic to the resin cement

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PURPOSE: The objective of this study was to evaluate the effect of primer-cement systems with different functional phosphate monomers on the adhesion of zirconia to dentin with and without aging protocols. MATERIALS AND METHODS: Bovine teeth (N = 180) were embedded in acrylic resin after sectioning their roots with with their coronal parts exposed. The buccal surface of each tooth was polished with silicon carbide papers (#200, 400, 600) until dentin exposure. Sintered zirconia cylinders (N = 180) (Ø: 3.4 mm; height: 4 mm) (Vita In-Ceram 2000) were prepared and distributed into 18 groups (n = 10 per group) considering the following factors: "Cementation System" (Panavia F - PAN; RelyX Ultimate - ULT, Multilink N - MULT) and "aging" (water storage in distilled water at 37 °C for 24 h (control, C); 30 days (30D); 6 months (6 M) and thermocycling for 5000 (5TC), 10,000 (10TC) and 20,000 (20TC) thermal cycles (5-55 °C; dwell time: 30 s)". Zirconia and dentin cementation surfaces were conditioned according to the recommendations of the manufacturers of each resin cement. The cylinders were adhesively cemented to the dentin surfaces and the specimens were submitted to the aging protocols. After aging, the specimens were subjected to shear bond strength test (SBS) (1 mm/min) in a Universal Testing Machine and failure types were analyzed. The data (MPa) were statistically using Kruskal-Wallis followed by the Dunn test (α = 5%). The degree of conversion (DC) rates of the cementing systems were also measured. RESULTS: While without aging (24 h) no significant difference was found between the cement systems (p > 0.05), after 30D (4.3-5.4), the highest decrease in all groups were observed after 5TC (1.5-2.3) (p < 0.05). Overall, MULT and ULT presented significantly higher results than that of PAN (p < 0.05). Pre-test failures during TC were more frequent in the PAN group. Complete adhesive failures at the cement/dentin interface were more frequent for MULT (30-80%) and PAN (10-70%) and for ULT (20-90%) at the cement/ceramic interface. DC of the tested cements did not show significant difference. CONCLUSION: Adhesion performance of the primer-cement systems with different functional phosphate monomers on zirconia-dentin complex varied as a function of aging strategies with MULT and ULT delivering higher bond strength values. When failure types considered, none of the cement systems performed well on both ceramic and dentin.

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This study evaluated the effectiveness of a multi-mode adhesive (SBU-Scotch Bond Universal/3M) as a substitute for silica coating and silane application on the bonding of zirconia ceramics to resin cement. One-hundred and twenty sintered zirconia ceramic blocks (5 x 5 x 5 mm) were obtained, finished by grounding with silicon carbide paper (#600, #800, #1000 and #1200) and randomly divided into 12 groups (n=10) in accordance with the factors "surface treatment" (ScSi - silicatization + silanization; ScSBU - silicatization + SBU; SBU - SBU without photoactivation and SBUp - SBU photoactivated) and "ceramic" (Lava / 3M ESPE, Ceramill Zirconia / Amann Girrbach and Zirkonzahn / Zirkonzahn). Dual resin cement cylinders (RelyX Ultimate/3M ESPE) were subsequently produced in the center of each block using a silicon matrix (Ø=2 mm, h=5 mm) and photoactivated for 40 s (1200 mW/cm2). The samples were stored for 30 days in distilled water (37ºC) and submitted to shear bond strength test (1 mm/min, 100 KgF). Data (MPa) were analyzed under ANOVA (2 levels) and Tukey test (5%). Complementary analyzes were also performed. ANOVA revealed that only the factor "surface treatment" was significant (p=0.0001). The ScSi treatment (14.28A) promoted statistically higher bond strength values than the other ScSBU (9.03B), SBU (8.47B) and SBUp (7.82B), which were similar to each other (Tukey). Failure analysis revealed that 100% of the failures were mixed. The silica coating followed by the silanization promoted higher bond strength values of resin cement and ceramic, regardless of the zirconia ceramic or SBU.

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Abstract This study evaluated the effectiveness of a multi-mode adhesive (SBU-Scotch Bond Universal/3M) as a substitute for silica coating and silane application on the bonding of zirconia ceramics to resin cement. One-hundred and twenty sintered zirconia ceramic blocks (5 x 5 x 5 mm) were obtained, finished by grounding with silicon carbide paper (#600, #800, #1000 and #1200) and randomly divided into 12 groups (n=10) in accordance with the factors "surface treatment" (ScSi - silicatization + silanization; ScSBU - silicatization + SBU; SBU - SBU without photoactivation and SBUp - SBU photoactivated) and "ceramic" (Lava / 3M ESPE, Ceramill Zirconia / Amann Girrbach and Zirkonzahn / Zirkonzahn). Dual resin cement cylinders (RelyX Ultimate/3M ESPE) were subsequently produced in the center of each block using a silicon matrix (Ø=2 mm, h=5 mm) and photoactivated for 40 s (1200 mW/cm2). The samples were stored for 30 days in distilled water (37ºC) and submitted to shear bond strength test (1 mm/min, 100 KgF). Data (MPa) were analyzed under ANOVA (2 levels) and Tukey test (5%). Complementary analyzes were also performed. ANOVA revealed that only the factor "surface treatment" was significant (p=0.0001). The ScSi treatment (14.28A) promoted statistically higher bond strength values than the other ScSBU (9.03B), SBU (8.47B) and SBUp (7.82B), which were similar to each other (Tukey). Failure analysis revealed that 100% of the failures were mixed. The silica coating followed by the silanization promoted higher bond strength values of resin cement and ceramic, regardless of the zirconia ceramic or SBU.

Resumo Este estudo avaliou a efetividade de um adesivo "multi-mode" (Single Bond Universal/3M) como um substituto para a silicatização e aplicação do silano na resistência de união das cerâmicas de zircônia e um cimento resinoso. Para isso, 120 blocos cerâmicos sinterizados de zircônia nas dimensões de (5 x 5 x 5 mm) foram obtidos, lixados com lixas de granulação decrescente (#600, #800, #1000 e #1200) e divididos aleatoriamente em 12 grupos (n = 10), de acordo com os fatores "tratamento de superfície" (ScSi - silicatização + silanização; ScSBU - silicatização + Single Bond; SBU - SBU sem fotoativação e SBUp - SBU com fotoativação) e "cerâmica" (Lava/3M ESPE, Ceramill Zircônia/ Amann Girrbach e Zirkonzahn/Zirkonzahn). Posteriormente, cilindros de cimento resinoso dual (RelyX Ultimate/3M ESPE) foram confeccionados no centro de cada bloco com auxílio de uma matriz de silicone (Ø=2 mm; h=5 mm) e fotopolimerizados por 40 s (1200 mW/ cm²). Em seguida, as amostras foram armazenadas durante trinta dias em água destilada (37 °C) e submetidas ao ensaio de resistência de união ao cisalhamento (1 mm/min, 100 kgF). Os dados (MPa) foram analisados sob ANOVA (2 fatores) e teste de Tukey (5%). Análises complementares também foram realizadas. ANOVA revelou que apenas o fator "tratamento de superfície" foi significativo (p=0,0001). O tratamento ScSi (14.28A) promoveu valores de adesão estatisticamente superiores aos demais ScSBU (9.03B), SBU (8.47B) e SBUp (7.82B), os quais foram semelhantes entre si (Tukey). A Análise de falhas revelou que 100% da falhas que ocorreram foram mistas. A silicatização seguida da silanização promoveu a melhor resistência de união entre cimento resinoso e a cerâmica, independentemente do tipo da cerâmica ou do SBU.

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Objective: The aim of this study was to systematically review the literature to assess static fracture strength tests applied for fixed dental prostheses (FDPs) and analyze the impact of periodontal ligament (PDL) simulation on the fracture strength. Material and Methods: Original scientific papers published in MEDLINE (PubMed) database between 01/01/1981 and 10/06/2018 were included in this systematic review. The following MeSH terms, search terms, and their combinations were used:"Dentistry", "Fracture Strength", "Fracture Resistance", "Fixed Dental Prosthesis", "Fixed Partial Denture", "Mechanical Loading". Two reviewers performed screening and analyzed the data. Only the in vitro studies that reported on load-bearing capacity of only FDP materials where mean or median values reported in Newnton (N) were included. Results: The selection process resulted in the 57 studies. In total, 36 articles were identified related to allceramics, 10 were fiber reinforced composite resin (FRC), 8 of composite resin (C) and 5 of metalceramic. As for clinical indications, 3 and 4-unit FDPs were more commonly studied (n=32; with PDL=21, without PDL=11), followed by single crowns (n=13; with PDL=3, without PDL=10), and inlay-retained and cantilever FDPs (n=12; with PDL=8, without PDL=4). Conclusion: An inclination for decreased static fracture strength could be observed with the simulation of PDL but due to insufficient data this could not be generalized for all materials used for FDPs (AU)

Objetivo: O objetivo deste estudo foi revisar sistematicamente a literatura para avaliar os testes de força de fratura estática aplicados para próteses dentárias fixas (FDPs) e analisar o impacto da simulação do ligamento periodontal (PDL) na resistência à fratura. Material e Métodos: Artigos científicos originais publicados na base de dados MEDLINE (PubMed) entre 01/01/1981 e 10/06/2018 foram incluídos nesta revisão sistemática. Foram utilizados os seguintes termos MeSH, termos de pesquisa e suas combinações: "Dentistry", "Fracture Strength", "Fracture Resistance", "Fixed Dental Prosthesis", "Fixed Partial Denture", "Mechanical Loading". Dois revisores realizaram a triagem e analisaram os dados. Apenas os estudos in vitro que reportaram a capacidade de suporte de carga de FDP, com os valores das médias ou medianas relatados em Newton (N) foram incluídos. Resultados: O processo de seleção resultou em 57 estudos. No total, 36 artigos foram identificados relacionados à restaurações totalmente cerâmicas, 10 em resina composta reforçada com fibra (FRC), 8 em resina composta (C) e 5 em metalocerâmica. Quanto às indicações clínicas, os PDF de 3 e 4 unidades foram mais comumente estudados (n = 32; com PDL = 21, sem PDL = 11), seguidos de coroas isoladas (n = 13; com PDL = 3, sem PDL = 10) e FDPs retidas por inlays e com cantilever (n = 12; com PDL = 8, sem PDL = 4). Conclusão: Uma inclinação para a diminuição da resistência à fratura estática pôde ser observada com a simulação do PDL, mas devido a dados insuficientes, isso não pôde ser generalizado para todos os materiais utilizados para as FDPs (AU)

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Objective: To evaluate the effect of different irrigation solutions prior to post cementation on the resin bonding to bovine root dentine. Material and Methods: 60 bovine roots (16 mm) were prepared to 12 mm with specific drill of a double-tapered fiber post system, included in PMMA, and divided into 6 groups, considering the irrigation solutions (IS) prior to cementation: Gr1- saline solution (control), Gr2- NaOCl 0.5 %, Gr3- NaOCl 1 %, Gr4- NaOCl 2.5 %, Gr5- NaOCl 5 %, Gr6- Chlorexidine 2 % (solution). The root canals were irrigated with IS 20 ml during 10 min. Then they were rinsed with 20 ml of distilled water and dried with paper points. One fiber post was molded with polyvinylsiloxane and 60 posts made of resin cement (PRC) were obtained moments before the cementation. The root canal dentin was etched with H2PO3 37 %/15 s + washing/drying, a multi-bottle etch&rinse adhesive system was applied and the PRC were resin luted with dual resin cement (DuolinkTM, Bisco). Each specimen was cut into 4 slices of ±1.8mm in thickness and submitted to push-out test (1 mm/min). Results: ANOVA showed that bond strength was significantly affected by IS (P < 0.0001). The highest bond strengths (MPa) were those for the groups 4 (3.51 ± 1.52) and 5 (3.0 ± 1.16). The groups 1 (0.70 ± 0.30), 2 (0.80 ± 0.24), 3 (1.26 ± 0.57) and 6 (0.90 ± 0.41) were statistically similar to each other. Conclusion: The resin bonding to the root dentine was higher when higher concentrations of hypochlorite solutions were used. (AU)

Objetivo: Avaliar o efeito de diferentes soluções de irrigação antes da cimentação do pino na resistência de união da resina à dentina radicular bovina. Material e Métodos: Foram preparadas 60 raízes bovinas (16 mm) a 12 mm com broca específica de um sistema de pino de fibra com dupla conicidade, incluídas no PMMA, e divididas em 6 grupos, considerando as soluções irrigadoras (IS) antes da cimentação: Gr1-Solução salina (controle), Gr2-NaOCl 0,5 %, Gr3-NaOCl 1 %, Gr4-NaOCl 2,5 %, Gr5-NaOCl 5 %, Gr6-Clorexidina 2 % (solução). Os canais radiculares foram irrigados com 20 ml de IS durante 10 min. Depois, foram lavados com 20 ml de água destilada e secos com pontas de papel. Um pino de fibra foi moldado com polivinilsiloxano e 60 pinos de cimento resinoso (PRC) foram obtidos momentos antes da cimentação. A dentina radicular foi condicionada com H2PO3 37 %/15 s + lavagem/ secagem, aplicou-se o sistema de adesivo e o PRC foi cimentado com cimento resinoso dual (DuolinkTM, Bisco). Cada amostra foi cortada em 4 fatias de ± 1,8 mm de espessura e submetida a teste push-out (1 mm/ min). Resultados: ANOVA mostrou que a força de união foi significativamente afetada pelo IS (P< 0,0001). As maiores resistências de união (MPa) foram para os grupos 4 (3,51 ± 1,52) e 5 (3,0 ± 1,16). Os grupos 1 (0,70 ± 0,30), 2 (0,80 ± 0,24), 3 (1,26 ± 0,57) e 6 (0,90 ± 0,41) foram estatisticamente semelhantes entre si. Conclusão: A resistência de união da resina à dentina radicular foi maior quando foram utilizadas concentrações maiores de soluções de hipoclorito. (AU)

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The aim of this study was to evaluate the effects of different light-curing units and resin cement curing types on the bond durability of a feldspathic ceramic bonded to dentin. The crowns of 40 human molars were sectioned, exposing the dentin. Forty ceramic blocks of VITA VM7 were produced according to the manufacturer's recommendations. The ceramic surface was etched with 10% hydrofluoric acid / 60s and silanized. The dentin was treated with 37% phosphoric acid / 15s, and the adhesive was applied. The ceramic blocks were divided and cemented to dentin according to resin cement / RC curing type (dual- and photo-cured), light-curing unit (halogen light / QTH and LED), and storage conditions (dry and storage / 150 days + 12,000 cycles / thermocycling). All blocks were stored in distilled water (37°C / 24h) and sectioned (n = 10): G1 - QTH + RC Photo, G2 - QTH + RC Dual, G3 - LED + RC Photo, G4 - LED + RC Dual. Groups G5, G6, G7, and G8 were obtained exactly as G1 through G4, respectively, and then stored and thermocycled. Microtensile bond strength tests were performed (EMIC), and data were statistically analyzed by ANOVA and Tukey's test (5%). The bond strength values (MPa) were: G1 - 12.95 (6.40)ab; G2 - 12.02 (4.59)ab; G3 - 13.09 (5.62)ab; G4 - 15.96 (6.32)a; G5 - 6.22 (5.90)c; G6 - 9.48 (5.99)bc; G7 - 12.78 (11.30)ab; and G8 - 8.34 (5.98)bc. The same superscript letters indicate no significant differences. Different light-curing units affected the bond strength between ceramic cemented to dentin when the photo-cured cement was used, and only after aging (LED > QTH). There was no difference between the effects of dual- and photo-cured resin-luting agents on the microtensile bond strength of the cement used in this study.

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The aim of this study was to evaluate the effects of different light-curing units and resin cement curing types on the bond durability of a feldspathic ceramic bonded to dentin. The crowns of 40 human molars were sectioned, exposing the dentin. Forty ceramic blocks of VITA VM7 were produced according to the manufacturer's recommendations. The ceramic surface was etched with 10% hydrofluoric acid / 60s and silanized. The dentin was treated with 37% phosphoric acid / 15s, and the adhesive was applied. The ceramic blocks were divided and cemented to dentin according to resin cement / RC curing type (dual- and photo-cured), light-curing unit (halogen light / QTH and LED), and storage conditions (dry and storage / 150 days + 12,000 cycles / thermocycling). All blocks were stored in distilled water (37°C / 24h) and sectioned (n = 10): G1 - QTH + RC Photo, G2 - QTH + RC Dual, G3 - LED + RC Photo, G4 - LED + RC Dual. Groups G5, G6, G7, and G8 were obtained exactly as G1 through G4, respectively, and then stored and thermocycled. Microtensile bond strength tests were performed (EMIC), and data were statistically analyzed by ANOVA and Tukey's test (5%). The bond strength values (MPa) were: G1 - 12.95 (6.40)ab; G2 - 12.02 (4.59)ab; G3 - 13.09 (5.62)ab; G4 - 15.96 (6.32)a; G5 - 6.22 (5.90)c; G6 - 9.48 (5.99)bc; G7 - 12.78 (11.30)ab; and G8 - 8.34 (5.98)bc. The same superscript letters indicate no significant differences. Different light-curing units affected the bond strength between ceramic cemented to dentin when the photo-cured cement was used, and only after aging (LED > QTH). There was no difference between the effects of dual- and photo-cured resin-luting agents on the microtensile bond strength of the cement used in this study.

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The aim of this study was to evaluate the influence of 2 different surface polishing procedures-glazing and manual polishing-on the roughness of ceramics processed by computer-aided design/computer-aided manufacturing (CAD/CAM) and conventional systems (stratification technique). Eighty ceramic discs (diameter: 8 mm, thickness: 1 mm) were prepared and divided among 8 groups (n = 10) according to the type of ceramic disc and polishing method: 4 GZ and 4 MP. Specimens were glazed according to each manufacturer's recommendations. Two silicone polishing points were used on the ceramic surface for manual polishing. Roughness was measured using a surface roughness tester. The roughness measurements were made along a distance of 2 mm on the sample surface and the speed of reading was 0.1 mm/s. Three measurements were taken for each sample. The data (µm) were statistically analyzed using analysis of variance (ANOVA) and Tukey's test (α = 0.05). Qualitative analysis was performed using scanning electron microscopy (SEM). The mean (± SD) roughness values obtained for GZ were: 1.1 ± 0.40 µm; 1.0 ± 0.31 µm; 1.6 ± 0.31 µm; and 2.2 ± 0.73 µm. For MP, the mean values were: 0.66 ± 0.13 µm; 0.43 ± 0.14 µm; 1.6 ± 0.55 µm; and 2.0 ± 0.63 µm. The mean roughness values were significantly affected by the ceramic type (P = 0.0001) and polishing technique (P = 0.0047). The SEM images confirmed the roughness data. The manually polished glass CAD/CAM ceramics promoted lower surface roughness than did the glazed feldspathic dental ceramics.

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PURPOSE: The aim of this study was to evaluate the marginal discrepancy (MD) and internal discrepancy (ID) of ceramic crowns manufactured by a CAD/CAM system, having different finish lines. The hypotheses tested were that the finish line type would not influence the MD or ID of the crowns, and ID would not change in different regions. MATERIALS AND METHODS: Three aluminum master dies (height: 5.5 mm, Ø: 7.5 mm, conicity: 6°) with different finish lines (TC: tilted chamfer; LC: large chamfer; RS: rounded shoulder) were manufactured. Ten impressions were made from each master die using a modified parallelometer. Impressions were poured in type IV dental stone, and 30 ceramic crowns (IPS Empress CAD, Ivoclar) were subsequently milled. The crowns were fixed on their respective metallic die using a metallic fixation device. The distance between the external edges of the crown to the edge of the cervical preparation was performed at 50 points on the respective metallic die (MD analysis). With the replica technique, the ID values of each crown were further evaluated at 12 points equidistant to each other in three regions: radius (R), axial (A), and occlusal (Occl). The measurements were performed using an optical microscope (250×). The data (µm) were analyzed using ANOVA and Tukey's test (5%). RESULTS: The RS group (28.24 ± 11.42 µm) showed significantly lower MD values (p= 0.001) than those of TC (99.92 ± 18.32 µm) and LC (64.71 ± 25.64 µm) groups, both of which also differed statistically from one another. The ID results demonstrated significantly lower values in the LC group (183.01 ± 62.82 µm) (p= 0.0014) than those of TC (216.26 ± 83.23 µm) and RS (219.12 ± 87.24 µm) groups. ID results of TC and RS were not significantly different. Additionally, the ID results showed significant differences among the regions (p= 0.0001). The null hypotheses were rejected. CONCLUSION: The RS finish line produced MD values significantly lower than tilted and large chamfer, but large chamfer presented the lowest internal discrepancy values. Independent of the finish line type, internal discrepancy was the lowest in the axial region followed by radius and occlusal regions.

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Avaliar a influência de diferentes unidadespolimerizadoras na resistência de união ao cisalhamento entrediferentes metais a uma resina laboratorial. Método: Foramconfeccionados 60 cilindros metálicos (5mm x 4mm), sendotrinta em titânio comercialmente puro (Ticp) e trinta em liga deouro-paládio (Au-Pd), jateados (Al2O3 110μm, 20s, 2,9 bar)previamente à aplicação de resina. Foram aplicadas duascamadas do opaco (Sinfony) e posteriormente foi aplicada aresina de revestimento estético Sinfony na superfície deunião ao material estético nos cilindros metálicos. O opaco ea resina de revestimento foram polimerizados em diferentesunidades, de acordo com os grupos experimentais: GrA1-Ticp + Visio Beta (3M ESPE/EUA); GrA2 – Ticp + Powerlux(EDG, Brasil); GrA3 – Ticp + Strobolux (EDG, Brasil); GrB1 –Au-Pd + Visio Beta; GrB2 – Au-Pd + Powerlux; GrB3 – Au-Pd+ Strobolux. As amostras foram submetidas ao cisalhamentoem máquina de teste universal (EMIC/Brasil) com célula decarga com capacidade de 500 Kg (0,5 mm/min). Os dadosobtidos (MPa) foram submetidos à análise de variância ANOVA2 fatores e teste Tukey (5%). Resultados: As médias edesvio-padrão obtidos foram (MPa): GrA1: 6,1±1,9; GrA2:5,6±1,4; GrA3: 5,5±2,5; GrB1:9,46±2,5; GrB2:7,4±2; GrB3:8,2±3,1. Conclusão: As ligas de Au-Pd promovem uma maiorresistência de união à resina indireta Sinfony comparado aoTicp, independente da unidade polimerizadora utilizada...

To evaluate the effect of different polymerizationunits on the shear bond strength between different metalsand a laboratorial resin. Material and Method: Sixty metalliccylinders were obtained (5mm x 4mm), thirty in commerciallypure titanium (CpTi) and thirty in gold-palladium alloy (Au-Pd),which were sandblasted (Al2O3 110μm, 20s, 2,9 bar) beforethe resin application. Two layers of opaque (Sinfony Opaque)were applied with a brush and with the assistance of theteflon matrix, the esthetic veneering resin was applied onthe metallic cylinders. The opaque and veneering resin werepolymerized at different polymerized, according toexperimental groups: GrA1 – CpTi + Visio Beta (3M ESPE/EUA); GrA2 – CpTi + Powerlux (EDG, Brazil); GrA3 – CpTi +Strobolux (EDG, Brasil); GrB1 – Au-Pd + Visio Beta; GrB2 –Au-Pd + Powerlux; GrB3 – Au-Pd + Strobolux. The specimenswere submitted to shear test in a universal testing machine(model DL/1000-EMIC) with a 500kg load cell (0,5 mm/min).The data (MPa) were submitted to the analysis of variance(ANOVA) and tukey’s test (5%). Results: The means andstandard deviations obtained were (MPa): GrA1: 6.1±1.9;GrA2: 5.6±1.4; GrA3: 5.5±2.5; GrB1: 9.4±2.5; GrB2: 7.4±2; GrB3:8.2±3.1. Conclusion: The Au-Pd alloys promote higher bondstrength to sinfony indirect resin compared to Ticp, regardlessthe polymerized unit used...

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Avaliar a influência de diferentes dispositivos decarregamento na resistência de união ao cisalhamento entreo titânio comercialmente puro (Ticp) e uma resina indireta.Materiais e Método: Foram confeccionados trinta cilindrosmetálicos (CM) em Ticp (altura: 5 mm; diâmetro: 4 mm). OsCM tiveram sua superfície adesiva jateada com Al2O3 110 μm.Todos os cilindros foram imersos em álcool isopropílico 10% elimpos em banho ultra-sônico (10 min). Duas camadas(espessura: 0,2 mm) de Sinfony Opaco foram aplicadas sobrea superfície jateada dos CM e submetidas à polimerização nasunidades Visio Alfa e Visio Beta. Com auxílio de um dispositivode teflon, a resina de recobrimento estético Sinfony foi aplicada(altura: 5 mm; diâmetro: 4 mm) sobre a camada de opaco epolimerizada de acordo com as recomendações do fabricante.As amostras foram divididas em três grupos, de acordo com otipo de dispositivo para carregamento utilizado para o ensaiode cisalhamento (n=10): Gr1- pistão, Gr2- cinzel reto e Gr3-cinzel reto com entalhe. As amostras foram submetidas aoensaio de cisalhamento na máquina de ensaio universal. Osdados (MPa) foram submetidos à análise de variância (ANOVA).Resultados: As médias e desvios-padrões obtidos foram: Gr1-5,49±1,41 MPa; Gr2- 5,37±0,8 MPa e Gr3- 5,56±1,92 MPa.Conclusão: Todos os dispositivos testados apresentaramdesempenho semelhante na análise da união metal/resina(p=0,9550>0,05)...

The aim of this study was to evaluate the influenceof the different devices on the shear bond strength betweenthe titanium (Ticp) and an indirect resin. Material and Method:Thirty metallic cylinders of Ticp (height: 5 mm; diameter: 4mm) obtained by machining of pure commercially titaniumbar (Ticp). The metallic cylinders had their adhesive surfacesandblasted (Al2O3; 110μm). All cylinders were immerged inisopropyl alcohol 10% and were cleaned ultrasonically (10min). Two layers of the resin Opaque Sinfony were applied onthe metallic cylinders and cured in the Visio Alfa and VisioBeta units, according to the manufacturer’s recommendation.The esthetic resin Sinfony was applied (height: 5 mm; diameter:4 mm) on the opaque layer using a teflon device, according tothe manufacturer’s instructions. The specimens were dividedinto three groups, according to the shear device used (n=10):Gr1: piston, Gr2: knife without a groove; Gr3: knife with a groove.The shear test was performed in a universal testing machine.Bond strength results were analyzed using one-way ANOVA.Results: The means and standard deviations obtained were:Gr1- 5.49 ± 1.41 MPa, Gr2- 5.37 ± 0.8 MPa and Gr3- 5.56 ±1.92 MPa. Conclusion: All devices used showed similarperformance on the bond strength between metal/resin(p=0.9550>0.05)...

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Objetivo: Avaliar a resistência de união ao cisalhamento entre um material de revestimento estético e um metal submetido a três tratamentos de superfície. Método: Foram confeccionados trinta cilindros metálicos, com 5 mm de comprimento e 4mm de diâmetro cada, obtidos por meio de usinagem de barras de titânio comercialmente puro (Ticp). Os cilindros foram divididos em três grupos conforme o tratamento superficial (n=10): Grupo 1 - jateamento com óxido de alumínio (150 micrometros); Grupo 2 - Sistema Rocatec (3M/ESPE): jateamento com óxido de alumínio (Al2O3) 110 micrometros (Rocatec-pre powder) e com sílica (Rocatec-plus powder) + silano (Rocatec-Sil) e Grupo 3 - Sistema CoJet (3M/ESPE): jateamento com partículas de sílica 30 micrometros + Silano (ESPE Sil). Para confecção dos espécimes, foi aplicado sobre cada base metálica o sistema opaco (Sinfony Opaco, 3M ESPE/EUA) e posteriormente a resina composta para restauração indireta (Sinfony, 3M ESPE/EUA). Os espécimes foram armazenados em água destilada (37 graus Celsius / 24 horas) e submetidos ao ensaio de cisalhamento em máquina de ensaio universal (EMIC, modelo DL- 1000), com célula de carga de 500 Kgf, a uma velocidade constante de 0,5mm/min. Os dados obtidos (MPa) foram submetidos ao teste ANOVA (1 fator) e teste de Tukey (5%). Resultados: Observou-se que o grupo 1 (20,01 - 3,12) diferiu estatisticamente do grupo 2 (27,83 - 3,02) e do grupo 3 (26,91 - 3,65) que, entre si, não diferiram estatisticamente. Conclusão: O tratamento da superfície do Ticp com Rocatec ou CoJet gera maior resistência de união entre o Ticp e a resina Sinfony.

Objective: To assess the shear bond strength of an esthetic coatingmaterial and a metal subjected to three surface treatments. Methods: Thirty metallic cylinders (5 mm high x 4 mm diameter) were fabricated from machining of commercially pure titanium (CPTi) bars. The cylinders were assigned to three groups (n=10), according to the surface treatment: Group 1: 150- micrometrics aluminum oxide particle air abrasion; Group 2 - Rocatec system (3M/ESPE):110- micrometrics aluminum oxide particle air abrasion (Rocatec-pre powder) and silica air abrasion (Rocatec-plus powder) + silane (Rocatec- Sil); and Group 3 - CoJet system (3M/ESPE): 30- micrometrics silica particle air abrasion + silane (ESPE Sil). The specimens were fabricated by applying the opaque system (Sinfony Opaco, 3M/ESPE) followed by indirect composite resin (Sinfony, 3M ESPE/USA). After storage in distilled water at 37 degrees celsius for 24 hours, the specimens were tested in shear strength in a universal testing machine (EMIC, model DL- 1000) with a 500 kgf charge cell at 0.5 mm/min crosshead speed. The obtained data (MPa) were subjected to one-way ANOVA and Tukey's test at 5% significance level. Results: Group 1 (20.01 - 3.12) was statistically different from Group 2 (27.83 -3.02) and Group 3 (26.91 - 3.65). Groups 2 and 3 did not differ significantly from each other. Conclusion: The surface treatment of CPTi with Rocatec or CoJet produced greater bond strength between CPTi and Sinfony composite resin.

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