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The objective of this study was to create injectable photo-crosslinkable biomaterials, using gelatin methacryloyl (GelMA) hydrogel, combined with a decellularized bone matrix (BMdc) and a deproteinized (BMdp) bovine bone matrix. These were intended to serve as bioactive scaffolds for dentin regeneration. The parameters for GelMA hydrogel fabrication were initially selected, followed by the incorporation of BMdc and BMdp at a 1% (w/v) ratio. Nano-hydroxyapatite (nHA) was also included as a control. A physicochemical characterization was conducted, with FTIR analysis indicating that the mineral phase was complexed with GelMA, and BMdc was chemically bonded to the amide groups of gelatin. The porous structure was preserved post-BMdc incorporation, with bone particles incorporated alongside the pores. Conversely, the mineral phase was situated inside the pore opening, affecting the degree of porosity. The mineral phase did not modify the degradability of GelMA, even under conditions of type I collagenase-mediated enzymatic challenge, allowing hydrogel injection and increased mechanical strength. Subsequently, human dental pulp cells (HDPCs) were seeded onto the hydrogels. The cells remained viable and proliferative, irrespective of the GelMA composition. All mineral phases resulted in a significant increase in alkaline phosphatase activity and mineralized matrix deposition. However, GelMA-BMdc exhibited higher cell expression values, significantly surpassing those of all other formulations. In conclusion, our results showed that GelMA-BMdc produced a porous and stable hydrogel, capable of enhancing odontoblastic differentiation and mineral deposition when in contact with HDPCs, thereby showing potential for dentin regeneration.

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Objective: The aim of this in vitro study w as t o analyze the influence of the titanium dioxide nanotubes i n a self-cure mode polymerization of a dual resin luting agent through push out bond strength and radiopacity tests. Material and Methods: After mixed with a commercial du al self-adhesive resin cement, three concentrations o f tit anium dioxide nanotubes (0.3, 0.6, and 0.9% by weight) we re analyzed in self-curing mode. T he bond strength to bovine root dentin and fi berglass posts was assessed with the push out bond str ength t est and was evaluated in three thirds (cervical, middle and apical) (n=10), followed by failure mode analysis (SEM), and the ISO standard 9917-2 was followed for radiopacity test (n=10). Data were statistically analyzed by one-way ANOVA test, followed by Tukey's test (α=0.05). Results: Reinforced self-adhesive resin cement with 0.6% titanium dioxide nanotubes showed significant difference compared to the control gr oup for push out test (p=0.00158). The modified groups did not s how significant difference among thirds (p=0.782). Radiopacity sh owed higher value for group w ith 0.9% titanium dioxide nanotubes in comparison w ith control group (p<0.001). Conclusion: The addition of titanium dioxide nanotubes to a self-adhesive resin cement increased the bond strength to dentin and radiopacity values in the self-cure polymerization mode (AU)

Objetivo: O objetivo deste estudo in vitro foi analisar a influência de nanotubos de dióxido de titânio na polimerização química de um agente cimentante resinoso dual através de testes de resistência à união e radiopacidade. Material e Métodos: Após misturado com um cimento resinoso auto-adesivo comercial, três concentrações de nanotubos de dióxido de titânio (0,3, 0,6 e 0,9% em peso) foram analisadas. A resistência da união para a dentina da raiz bovina e os pinos de fibra de vidro foi avaliada pelo teste de push-out e avaliada em três terços (cervical, médio e apical) (n = 10), seguido pelo análise de modo de falha (MEV) e a norma ISO 9917-2 foi seguido para teste de radiopacidade (n = 10). Os dados foram analisados estatisticamente pelo teste ANOVA um fator seguido do teste de Tukey (α = 0,05). Resultados: O cimento resinoso auto-adesivo reforçado com nanotubos de dióxido de titânio a 0,6% mostrou diferença significativa em comparação com o grupo controle para teste de push-out (p=0,00158). Os grupos modificados não mostraram diferença significativa entre os terços (p=0,782). A radiopacidade mostrou maior valor para o grupo com nanotubos de dióxido de titânio 0,9% em comparação com o grupo controle (p<0,001). Conclusão: A adição de nanotubos de dióxido de titânio a um cimento resinoso auto-adesivo aumentou a os valores de resistência de união à dentina e radiopacidade no modo de polimerização química do agente cimentante (AU)

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Commercial Yttria-tetragonal zirconia polycrystalline (Y-TZP) was subjected to surface treatments, and the bond strength of dual resin cement to Y-TZP and failure modes were evaluated. Disks (12 mm × 2 mm), cylinders (7 mm × 3.3 mm), and bars (25 mm × 5 mm × 2 mm) were milled from Y-TZP CAD-CAM blocks, divided into seven groups, and subjected to different surface treatments; silicatization was used as control. On the basis of the literature, this study evaluated modifications with films containing SiO2 nanoparticles and silane; SiO2+ZrO2­SiO2 (50%) and ZrO2 (50%) nanoparticles, SiO2+ZrO2/Silane-SiO2 (50%) and ZrO2 (50%) nanoparticles, and silane. Specimens were analyzed by wettability (n = 3), surface free energy (n = 3), X-ray diffraction (n = 1), Fourier transform infrared spectroscopy (FTIR) (n = 1), roughness (n = 5), shear bond test (n = 10), and dynamic modulus (n = 3). Specimens treated with hydrofluoric acid­HF 40% presented significantly higher contact angle and lowest surface free energy (p < 0.05). The SiO2/Silane presented crystalline SiO2 on the surface. The surface roughness was significantly higher for groups treated with nanofilms (p < 0.05). Shear bond strength was significantly higher for silicatization, HF 40%/silicatization, SiO2/Silane, and SiO2+ZrO2/Silane groups. The proposed treatments with nanofilms had potentially good results without prejudice to the physicochemical characteristics of zirconia. Generally, groups that underwent silica surface deposition and silanization had better bond strength (p < 0.005).

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OBJECTIVES: This study evaluated the effect of TiO2 nanoparticles + dense hydroxyapatite (HA) on human osteoblast cells (SAOS-2). METHODS: Particulate bovine HA powder with or without the addition of either 5 or 8 % TiO2 (HA, HA/TiO2Np5 % or HA/TiO2Np8 %) were pressed into disks (Ø = 12.5 mm; thickness = 1.3 mm) uniaxially (100 MPa) and isostatically (200 MPa/1 min) and sintered at 1300 °C. Y-TZP disks were used as control. The following tests were performed: Scanning Electron Microscopy and Dispersive Energy Spectroscopy (SEM/EDS), Atomic Force Microscopy (AFM), cell viability assay (Alamar Blue-AB) and mineralized matrix deposition (Alizarin Red-AR). AB and AR data were submitted to 2-way ANOVA/Tukey tests and ANOVA/Tukey tests, respectively. RESULTS: SEM revealed that the surface of HA/TiO2Np5% resembles DPBHA surface, but also contains smaller granules. HA/TiO2Np8% characteristics resembles HA/TiO2Np5% surface, but with irregular topography. Y-TZP showed a typical oxide ceramic surface pattern. EDS revealed Ca, O, and P in all samples. C, O, and Zr appeared in Y-TZP samples. AFM data corroborates SEM analysis. AB test revealed excellent cellular viability for HA/TiO2Np5% group. AR test showed that all groups containing TiO2np had more mineralized matrix deposition than all other groups, with statistically differences between HA/TiO2Np8% and HA cultivated in non-osteogenic medium. Culture in osteogenic medium exhibited much more mineralized matrix deposition by TiO2np groups. SIGNIFICANCE: In conclusion, the addition of TiO2np showed chemical, superficial, and biological changes in the reinforced materials. HA/TiO2Np5% showed the best results for cell viability and HA/TiO2Np8% for mineralized matrix deposition.

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OBJECTIVES: To characterize the behavior of three different polymeric agents before and after an erosive challenge on dentin permeability, to analyze their degradation in both conditions, and to analyze their degree of conversion (DC). METHODS: The permeability of human dentin disks (1.0 ± 0.2 mm) was measured with smear layer, after its removal, after treatment (LpTreat) with Gluma Desensitizer, PRG Barrier Coat (PBC) or Icon infiltrant (n = 11/group) and after exposure to citric acid (LpEro) (6%, pH 2.1, 1 min). The specimens were analyzed under a Laser Scanning Confocal Microscope (n = 2/group) and the products' DC were calculated. Data were subjected to 2-way repeated measures ANOVA and post-hoc Bonferroni (permeability analysis), to paired t-test (for specimens treated with Icon) and to t-test (DC analysis) (α < 0.05). RESULTS: Icon showed the lowest LpTreat and LpEro values, while PBC and Gluma did not differ from each other under these conditions. Icon and PBC showed LpEro similar to a dentin with smear layer. Under the Laser Scanning Confocal Microscope, more deposits were noticeable on dentin after treating with PBC. Gluma presented the deepest penetration in dentin. The DC of PBC was the highest. SIGNIFICANCE: Icon caused the highest reduction on permeability values, followed by PBC and Gluma. PBC generated more deposits covering dentin and seemed to be more efficient after an erosive challenge. The association of a polymeric resin with inorganic ion-releasing fillers seem to be a great strategy to manage dentin hypersensitivity under erosive conditions.

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OBJECTIVE: This study evaluated the microshear bond strength of a resin cement to Y-TZP after different methods of TiO2 nanotubes (nTiO2) incorporation on pre-sintered Y-TZP surfaces. METHODS: nTiO2 were synthesized and incorporated on Y-TZP slices as follows (n = 15): 1) nTiO2 mixed with isopropyl alcohol/manual application (MAl); 2) nTiO2 mixed with acetone/manual application (MAc); 3) nTiO2 mixed with isopropyl alcohol/high-pressure vacuum application (HPVAl); 4) nTiO2 mixed with acetone/high-pressure vacuum application (HPVAc). As controls, surfaces were sandblasted with Al2O3 (OX) or Rocatec silicatization (ROC). All ceramics were sintered after nTiO2 incorporation. Surface treatments of OX and ROC were made after sintering. Surfaces were characterized by confocal laser microscopy, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). Resin composite cylinders (1.40 mm diameter and 1 mm height) were cemented with a resin cement, stored in water at 37 °C for 24 h and thermocycled for 10 000 cycles before microshear bond strength evaluation. Data were analyzed with one-way ANOVA and Games-Howell (α = 0.05), and fracture analysis was performed using a stereomicroscope. RESULTS: EDS confirmed the presence of TiO2 on treated Y-TZP. The confocal analysis showed higher roughness for HPVAc and OX. There were significant differences between surface treatments (p < 0.001). HPVAl (22.96 ± 10.3), OX (34.16 ± 7.9) and ROC (27.71 ± 9.4) showed higher microshear bond strengths and were statistically similar (p > 0.05). MAC showed intermediary values, and HPVAc and MAl presented decreased bond strength, with a high percentage of premature debonding. CONCLUSION: High-pressure vacuum application of nTiO2 mixed with isopropyl alcohol was able to produce bond strength values compared to conventional air abrasion and Rocatec silicatization. SIGNIFICANCE: The infiltration of TiO2 nanostructures on the pre-sintered Y-TZP is an interesting approach that can improve bond strength without the need of sandblasting methods.

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OBJECTIVE: The aim of this paper is to present the results of a consensus meeting on the threshold property requirements for the clinical use of conventional glass-ionomer cements (GICs) for restorative indications. METHODS: Twenty-one experts on GICs evaluated the results of tests on mechanical and optical properties of 18 different brands of restorative GICs: Bioglass R [B], Chemfil Rock [CR], Equia Forte [EF], Gold Label 2 [GL2], Gold Label 9 [GL9], Glass Ionomer Cement II [GI], Ionglass [IG], Ion Z [IZ], Ionomaster [IM], Ionofil Plus [IP], Ionostar Plus [IS], Ketac Molar Easymix [KM], Magic Glass [MG], Maxxion R [MA], Riva Self Cure [R], Vidrion R [V], Vitro Fil [VF] and Vitro Molar [VM]. All experiments were carried out by a team of researchers from Brazil and England following strict protocols, under the same laboratory conditions throughout, and maintaining data integrity. RESULTS: There was consensus on: determining as primary properties of the material: compressive strength, microhardness, acid erosion and fluoride release, and as secondary properties: contrast ratio and translucency parameter, in order to rank the materials. Seven brands were below the thresholds for restorative indications: IZ, IM, IG, MA, VF, B and MG. CONCLUSIONS: Based on the primary properties adopted as being essential for restorative indications, the conventional restorative GICs that met the thresholds and could be considered suitable as long-term restorative materials were: EF, GI, GL9, KM, IP, GL2, IS, CR, V, VM and R. A decision-making process to select the best GIC must also include results from clinical trials. CLINICAL SIGNIFICANCE: This study provides a ranking of GICs that could be considered suitable as long-term restorative materials based on their main properties.

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OBJECTIVES: To evaluate the marginal adaptation and internal space of crowns produced by 4 CAD/CAM systems using microcomputed tomography (µCT) and replica technique (RT). MATERIALS AND METHODS: Monolithic lithium disilicate crowns were milled (Ceramill, Cerec, EDG, and Zirkonzahn) (n = 10). The cement film obtained with low viscosity silicone was scanned by the µCT system and captured by a stereomicroscope, according to RT. Two-way ANOVA followed by Tukey's test were used for statistical analysis (α = 0.05). A uniformity index (UI) was idealized to describe the distribution of crowns' internal space and submitted to the Kruskal-Wallis and Tukey's test (α = 0.05). The correlation between µCT and RT was performed by Pearson's Correlation Coeficient (α = 0.05). RESULTS: Marginal adaptation and internal space were statistically significant different between the experimental groups for the µCT and RT (p < 0.05). The medians of the 4 systems tested were within clinically acceptable range and the mean (± SD) highest marginal discrepancy was recorded in the Ceramill group at 133.0 ± 71.5 µm (µCT) and 90.6 ± 38.5 µm (RT). For internal fit, the UI disclosed a better distribution of the internal space for the Zirkonzahn group (p < 0.001). There was a strong correlation between the methods (p = 0.01 and r = 0.69). CLINICAL RELEVANCE: Because of the variability of the CAD/CAM systems available, evaluating their accuracy is of clinical interest. The 4 systems are capable to produce restorations adaptated within clinically appropriate levels. The µCT and RT are efficient adaptation methodologies.

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OBJECTIVE: To evaluate the translucency parameter (TP) and contrast ratio (CR) of different conventional restorative glass-ionomer cements (GICs). MATERIALS AND METHODS: Eighteen brands of GICs were evaluated. Five disks of each material were made following ISO 9917-1. The luminous reflectance and Central Bureau of the International Commission on Illumination parameters of disks were evaluated using a colorimeter, against backings of white and black, to obtain the translucent parameter and contrast ratio of different brands of glass-ionomer cements. The correlation between translucency parameter and contrast ratio was assessed with the Pearson correlation test. The translucent and contrast ratio parameters values were submitted to the one-way ANOVA and Tukey test for multiple comparisons (p < 0.05). RESULTS: There was a strong inverse relationship between CR and TP (r2  = 0.94, p < 0.001). The contrast ratio decreased as translucency increased. There were significant differences in TP and CR among brands (p < 0.001). CONLUSIONS: GICs exhibit different translucency and contrast ratio behavior. Some brands of GICs presented very low TP and this condition would be unacceptable for areas with esthetic demands. In addition, TP and CR showed a strong linear relationship. CLINICAL SIGNIFICANCE: The results found in this study demonstrated that the knowledge of the translucency and CR of different conventional restorative GICs is important in order to guide clinicians in the selection of restorative GICs for anterior teeth.

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OBJECTIVE: To evaluate the influence of the addition of functionalized and non-functionalized TiO2 nanostructures on properties of a resin composite. METHODS: TiO2 nanostructures were synthesized and functionalized, using 3-(aminopropyl)triethoxysilane (APTMS) and 3-(trimethoxysilyl)propyl methacrylate (TSMPM). Characterizations were performed with XRD, EDS, TEM, and TGA. Resin composites containing Bis-GMA/TEGDMA, CQ, DABE, and barium-aluminum silicate glass were produced according to TiO2 nanostructure (nanotube or nanoparticle), concentration (0.3 or 0.9 wt%), and functionalization (APTMS or TSMPM). The resin composite without nanostructures was used as control. The amount of fillers was kept constant at 78.3 wt% for all materials. The degree of conversion (DC - at 0 h and 24 h), maximum polymerization rate (Rpmax), and Knoop microhardness (KHN before and after ethanol softening) were evaluated. Data were analyzed with two-way ANOVA with repeated measures and Tukey's HSD (α = 0.05). RESULTS: TGA results demonstrated that functionalizations were effective for both nanostructures. For DC, resin composites, time and interaction effect were significant (p < 0.001). Higher DC was found for 0.3-wt%-functionalized-nanotubes at 24 h. For nanoparticles, only 0.9-wt%-non-functionalized and 0.3-wt%-APTMS-functionalized showed DC similar to the control and all other groups showed higher DC (p < 0.05). Rpmax was higher for 0.3-wt%-APTMS-nanotubes, which corresponded to higher DC after 24 h. The lowest Rpmax occurred for 0.9-wt%-TSMPM-nanotubes, which showed smaller DC at 0 h. For KHN, resin composites, ethanol softening and interaction effect were significant (p < 0.001). KHN decreased after ethanol softening all groups, except for 0.3-wt%-TSMPM-nanotubes, 0.9-wt%-TSMPM-nanotubes, and 0.3-wt%-non-functionalized-nanoparticles. CONCLUSION: The resin with 0.3-wt%-TSMPM-nanotubes showed higher DC after 24 h, while being the most stable material after the ethanol softening. SIGNIFICANCE: The addition of functionalized TiO2 nanostructures in resin-based materials may improve the properties of the material.

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The objective was to evaluate the compressive strength (CS), diametral tensile strength (DTS), flexural strength (FS), and Knoop microhardness (KH) of different conventional restorative glass-ionomer cements (GICs) and to correlate these mechanical properties (MP) with the stabilization time (ST) of their chemical bonds. Eighteen GICs were tested: Bioglass [B], Chemfil Rock [CR], Equia Forte [EF], Gold Label 2 [GL2], Gold Label 9 [GL9], Glass Ionomer Cement II [GI], Ionglass [IG], Ion Z[ IZ], Ionomaster [IM], Ionofil Plus [IP], Ionostar Plus [IS], Ketac Molar Easymix [KM], Magic Glass [MG], Maxxion R [Ma], Riva Self Cure [R], Vidrion R [V], Vitro Fil [VF] and Vitro Molar [VM]. The mechanical strength tests were performed in a universal testing machine. KH readings were done with a diamond indenter. STs were examined by Fourier Transform Infrared spectroscopy (FTIR). Data were analyzed with ANOVA and Tukey test (p<0.05). The Spearman rank test was used to evaluate the dependence between the MPs and ST results. The highest MP values were EF, GL2, GL9, GI and KM and the lowest for MG, MA, B, VF and IM. The longest ST was for GL2 and the shortest was for B. ST correlated positively with MP. GICs with longer chemical bonds ST are generally stronger and the ST value obtained from FTIR was useful in predicting the strength of GICs tested.

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PURPOSE: To evaluate the shear bond strength (SBS) between Y-TZP and a resin luting agent, after 1 of 2 enhancing strategies with TiO2--nts was applied, either to the resin luting agent or the Y-TZP mass, in different concentrations. METHODS: In the Strategy TiO2-nts on ceramic, the resin luting agent Panavia F2.0™ (Kuraray) and an experimental Y-TZP with added concentrations of TiO2--nts (0%, 1%, 2%, and 5% vol/vol) and a commercial Y-TZP, comprised 5 different groups (n = 10). In the Strategy TiO2-nts on cement, the resin luting agent RelyX U200™ (3 M ESPE) was added with different concentrations of TiO2--nts (0%, 0.3%, 0.6%, 0.9% wt/wt) luted to a commercial Y-TZP, comprising 4 different groups (n = 10). The Y-TZP discs were included in acrylic bases, and a cylinder (3 × 3 mm) of the correspondent luting agent for each respective group was applied over them. After 24 h, specimens were subjected to SBS assessments in a universal testing machine. Field emission scanning electron microscopy and energy dispersive X-ray spectroscopy analyses were also performed on Y-TZP surfaces. Data were analyzed via analysis of variance and Tukey tests (α = 0.05). RESULTS: TiO2-nts on ceramic influenced the bond strength significantly, but not linearly; TiO2-nts on cement did not influence bond strength when analyzed separately, nor in comparison with the first. CONCLUSION: Y-TZP enhancements with TiO2-nts led to a higher SBS with Panavia F2.0, a 5% TiO2--nt concentration presented the highest bond strength. Modified Rely X U200 did not improve SBS.

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Objective: multidisciplinary treatment has become increasingly common in dental offices and this treatment strategy is based on the achievement of a healthy, harmonious, and pleasant smile. In addition, the development of new ceramic systems and the possibility of making indirect restorations with a low thickness, such as laminates veneers, allowed combining highly satisfactory aesthetic properties, preserving the dental structure through minimally Invasive technique. Case report: this paper describes a multidisciplinary approach involving periodontics and restorative dentistry for the successful, functional, and aesthetic treatment in an adult patient. The digital smile design was performed as a guide to plan the clinical case considering factors such as tooth inclination and position, golden proportion, tooth size and shape. Discussion: based on these concepts, the present work reports, through a clinical case, the restoration of aesthetics and function with ceramic laminates veneers in lithium disilicate, in the case of anatomical correction and diastema closure. Conclusion: overall, the multidisciplinary treatment plan demonstrated to have greater advantages both for the aesthetics and function of the patient, as well as for the work team. During the 24-month follow-up, this case presented great functional and aesthetics results. (AU)

Introdução: o tratamento multidisciplinar tornou-se cada vez mais comum nos consultórios odontológicos, sendo uma estratégia baseada no tratamento da obtenção de um sorriso saudável, harmonioso e agradável. Além disso, o desenvolvimento de novos sistemas cerâmicos e a possibilidade de fazer restaurações indiretas com baixa espessura, como facetas laminadas, permitiram combinar propriedades estéticas altamente satisfatórias, preservando a estrutura dentária com o mínimo desgaste. Caso clínico: este artigo descreve uma abordagem multidisciplinar envolvendo Periodontia e Odontologia restauradora para um tratamento funcional e estético em um paciente adulto. O desenho digital do sorriso foi realizado como um guia para planejar o caso clínico, considerando fatores como inclinação e posição do dente, proporção áurea, tamanho e formato do dente. Discussão: com base nesses conceitos, o presente trabalho relata, através de um caso clínico, a restauração estética e funcional com laminados cerâmicos em dissilicato de lítio para correção anatômica e fechamento de diastemas. Conclusão: em geral, o plano de tratamento multidisciplinar demonstrou ter maiores vantagens tanto para a estética e função do paciente, quanto para a equipe de trabalho. Durante os 24 meses de acompanhamento, esse caso apresentou ótimos resultados funcionais e estéticos. (AU)

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Abstract The objective was to evaluate the compressive strength (CS), diametral tensile strength (DTS), flexural strength (FS), and Knoop microhardness (KH) of different conventional restorative glass-ionomer cements (GICs) and to correlate these mechanical properties (MP) with the stabilization time (ST) of their chemical bonds. Eighteen GICs were tested: Bioglass [B], Chemfil Rock [CR], Equia Forte [EF], Gold Label 2 [GL2], Gold Label 9 [GL9], Glass Ionomer Cement II [GI], Ionglass [IG], Ion Z[ IZ], Ionomaster [IM], Ionofil Plus [IP], Ionostar Plus [IS], Ketac Molar Easymix [KM], Magic Glass [MG], Maxxion R [Ma], Riva Self Cure [R], Vidrion R [V], Vitro Fil [VF] and Vitro Molar [VM]. The mechanical strength tests were performed in a universal testing machine. KH readings were done with a diamond indenter. STs were examined by Fourier Transform Infrared spectroscopy (FTIR). Data were analyzed with ANOVA and Tukey test (p<0.05). The Spearman rank test was used to evaluate the dependence between the MPs and ST results. The highest MP values were EF, GL2, GL9, GI and KM and the lowest for MG, MA, B, VF and IM. The longest ST was for GL2 and the shortest was for B. ST correlated positively with MP. GICs with longer chemical bonds ST are generally stronger and the ST value obtained from FTIR was useful in predicting the strength of GICs tested.

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INTRODUCTION: Polymer-based composite materials have been proposed as an alternative for single unit restorations, due to their resilient and shock absorbing behavior, in contrast to the brittleness of ceramic materials that could result in failure by fracture. OBJECTIVE: To evaluate the fatigue strength and damage modes of monolithic posterior resin nanoceramic and lithium disilicate glass ceramic crowns. METHODOLOGY: Twenty-six resin nanoceramic (RNC) and lithium disilicate glass ceramic (LD) 2 mm monolithic crowns (n=13) were cemented on composite resin replicas of a prepared tooth and subjected to cyclic load with lithium disilicate indenters for 2 million cycles. Specimens and indenters were inspected every 500,000 cycles and suspended when presenting fractures or debonding. Surviving specimens were embedded in epoxy resin, polished and subsurface damage was analyzed. Specimens presenting fractures or severe subsurface damage were considered as failures. Survival data was subjected to Fisher's exact test; damage modes were subjected to Mann-Whitney test (p<0.05). RESULTS: There were no debonding, cohesive or catastrophic failures. Considering subsurface damage, 53.8% of RNC and 46.2% of LD crowns survived the fatigue test, presenting no statistical difference. Chief damage modes were radial cracks for RNC and inner cone cracks for LD, presenting no statistical difference. CONCLUSIONS: The results suggest that if debonding issues can be resolved, resin nanoceramic figures can be an alternative to posterior crowns. Although distinct, damage modes revealed potential to cause bulk fracture in both glass ceramic and resin nanoceramic crowns.

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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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OBJECTIVES: To perform a systematic review of test methodologies on conventional restorative glass-ionomer cement (GIC) materials for mechanical and optical properties to compare the results between different GICs. MATERIAL AND METHODS: Screening of titles and abstracts, data extraction, and quality assessments of full-texts were conducted in search for in vitro studies on conventional GICs that follow the relevant specifications of ISO standards regarding the following mechanical and optical properties: compressive strength, flexural strength, color, opacity and radiopacity. SOURCES: The Latin American and Caribbean Health Sciences (LILACS), Brazilian Bibliography of Dentistry (BBO) databases from Latin-American and Caribbean System on Health Sciences Information (BIREME) and PubMed/Medline (US National Library of Medicine - National Institutes of Health) databases were searched regardless of language. Altogether, 1146 in vitro studies were selected. Two reviewers independently selected and assessed the articles according to pre-established inclusion/exclusion criteria. Among all the properties investigated, only one study was classified as being of fair quality that tested compressive strength and was included. It was observed that many authors had not strictly followed ISO recommendations and that, for some properties (diametral tensile strength and microhardness), there are no guidelines provided. CONCLUSIONS: It was not possible to compare the results for the mechanical and optical properties of conventional restorative GICs due to the lack of standardization of studies.

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Bulk-fill composites were introduced in dentistry to accelerate clinical procedures while providing adequate outcomes. Concerns regarding the use of bigger composite increments rely on the polymerization shrinkage and shrinkage stress, which may generate gaps on the adhesive interface and result in a reduced success rate. OBJECTIVE: To evaluate the polymerization shrinkage stress of different bulk-fill resin composites and their elastic modulus. MATERIALS AND METHODS: Fourteen specimens were made for each of the nine different resin composites (seven with 12 mm3 and seven with 24 mm3): Surefill SDR flow (SDR), X-tra Base (XB), Filtek Bulk Fill Flowable (FBF), Filtek Z350XT Flow (Z3F); Tetric Evo Ceram Bulk Fill (TBF), X-tra Fil (XF), Filtek Bulk Fill (FBP), Admira Xtra Fusion (ADM) and Filtek Z350 XT (Z3XT). Linear shrinkage stress was evaluated for 300 s with the aid of a linear shrinkage device adapted to a Universal Testing Machine. For each composite group, seven additional specimens (2x2x25 mm) were made and Young's modulus was evaluated with a 3-point bending device adapted in a Universal Testing Machine with 0.5 mm/min crosshead speed and 50 KgF loading cell. RESULTS: For 12 mm3 specimens, three-way ANOVA showed that only SDR and TBF generated lower stress after 20 s. Considering 300 s, TBF, SDR, and XF generated the lowest stress, followed by ADM, FBP, XB, and FBF, which were similar to Z3XT. Z3F generated the highest stress values for all time points. Considering 24 mm3 specimens after 20 s, all bulk fill composites generated lower stress than Z3XT, except XB. After 300 s, SDR, FBP, and ADM generated the lowest stress, followed by TBF and XF. For elastic modulus, one-way ANOVA showed that FBF, SDR, Z3F, and ADM presented the lowest values, followed by XB and TBF. FBP, Z3XT, and XF presented the highest elastic modulus among the evaluated composites. CONCLUSIONS: Bulk-fill resin composites presented equal to lower shrinkage stress generation when compared to conventional composites, especially when bigger increments were evaluated. Bulk-fill composites showed a wide range of elastic modulus values, but usually similar to "regular" composites.

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Atualmente, os procedimentos minimamente invasivos vêm sendo cada vez mais realizados, tanto para restaurações diretas quanto para restaurações indiretas. O surgimento dos laminados cerâmicos minimamente invasivos, comumente conhecidos como "lentes de contatos", permitem a confecção de restaurações cerâmicas com o mínimo de espessura para a cimentação. O sistema CAD/CAM possui muitas vantagens sendo possível confeccionar uma restauração indireta em poucos minutos, diminuindo etapas laboratoriais e, principalmente, a possibilidade de fresar restaurações cerâmicas com pouca espessura. No entanto, o conhecimento e o treinamento prático para utilização desse sistema são fundamentais para o sucesso clínico em casos de facetas minimamente invasivas. O presente relato de caso clínico destaca o insucesso de restaurações minimamente invasivas em dentes anteriores inferiores confeccionadas pelo sistema CAD/CAM e discute a necessidade do conhecimento do software do sistema para evitar o fracasso das restaurações (AU).

Nowadays, the minimally invasive procedures have been realized, for direct restorations as well as for indirect restorations. The appearance of the minimally invasive ceramic laminate veneers, commonly known as "contact lens", allow the construction of ceramic restorations with minimum thickness for cementation. The CAD/CAM system has many advantages being possible to make an indirect restoration obtaining in a few minutes, reducing laboratorial steps and, mainly, the possibility of milling a restoration with little thickness. However, the knowledge and the practical training of this system are fundamental to have clinical success in cases of minimally invasive veneer. The present case report emphasizes the failure of minimally invasive restorations in lower anterior teeth made in the CAD/CAM system and discusses the need to know the system software to avoid failure of restorations (AU).

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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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