Avaliação do desgaste fisiológico da camada de caracterização aplicada sobre cerâmicas odontológicas / Evaluation of the physiological wear of the applied characterization layer on dental ceramics

O presente estudo teve por objetivo avaliar o comportamento da camada de caracterização sobre zircônia de alta translucidez (YZHT, Vita YZ HT), cerâmica feldspática (FD/VMII, Vita Mark II) e silicato de lítio reforçado por zircônia (ZLS, Vita Suprinity) frente à simulação de desgaste fisiológico variando os antagonistas em YZHT, esteatita e cerâmica híbrida com polímero (Vita Enamic). Foram obtidos 120 discos (ø 12 mm, 1,2 mm de espessura) cerâmicos, sendo 30 de YZHT e FD, e 60 de ZLS, através de corte de blocos para CAD/CAM. As amostras de YZHT foram sinterizadas, e na sequência os grupos YZHT e FD receberam a camada de caracterização. A caracterização das amostras de ZLS foi realizada no mesmo ato da cristalização (ZLS1, etapa única) ou em queima posterior a cristalização (ZLS2, duas etapas). A caracterização foi realizada de acordo com as recomendações do fabricante e todas as amostras receberam aplicação de glaze e consequente queima. Os espécimes foram divididos em subgrupos (n=10) de acordo com os antagonistas: esteatita, cerâmica híbrida ou zircônia; em seguida, foram submetidos à simulação do desgaste fisiológico. Os parâmetros de rugosidade média (Ra) e largura média dos elementos do perfil de rugosidade (Rsm) foram analisados em diferentes momentos da simulação de desgaste fisiológico desde o início até o final da ciclagem. Após os 15.000 ciclos foram calculados a perda de massa dos discos cerâmicos e dos pistões antagonistas. Os resultados foram analisados estatisticamente por Anova 2 fatores e Tukey (p<0,05). Antes do desgaste, as cerâmicas não apresentaram diferenças para os parâmetros de rugosidade, Ra (p=0,3348), Rz (p=0,5590) e Rsm (p=0,5330). Os antagonistas não apresentaram diferenças para os parâmetros, Ra (p=0,0541) e Rsm (p=0,0613), enquanto que o parâmetro Rz (p=0,000) apresentou diferença, já que a esteatita (18,98 ± 2,98 µm) apresentou uma maior rugosidade média quando analisada a altura máxima do perfil quando comparado com os antagonistas em enamic (12,35 ± 0,91 µm) e zircônia (11,47 ± 0,89 µm). Após o desgaste, as cerâmicas continuaram sem apresentar diferenças estatísticas para os parâmetros de rugosidade, Ra (p=0,488), Rz (p=0,681) e Rsm (p=0,256). Os antagonistas não apresentaram diferença para o parâmetro Ra (p=0,124), porém, apresentaram diferença para o parâmetro Rz (p=0,000), já que a esteatita (57,98 ± 4,11 µm) apresentou uma maior média para tal parâmetro quando comparado com os antagonistas em enamic (44,86 ± 2,34 µm) e zircônia (37,81 ± 1,40 µm); e para o parâmetro Rsm (p=0,000), já que as médias da esteatita (502,72 ± 72,20 µm), enamic (385,67 ± 24,84 µm) e zircônia (268,94 ± 27,99 µm) apresentaram diferenças entre si. O tipo de cerâmica (p<0,0001) influenciou a perda de massa das amostras e a interação entre cerâmica e antagonista (p=0,0098), com isso influenciou a perda de massa dos pistões antagonistas. O grupo ZLS 2 apresentou a maior perda de massa entre os grupos testados. Todos os antagonistas testados apresentaram perda de massa semelhante contra o FD, enquanto a esteatita apresentou maior perda de massa quando testadas com amostras YHZT, ZLS 1 e ZLS 2. Todas as cerâmicas apresentaram rugosidade semelhante antes e após a simulação de desgaste. As amostras de cerâmicas apresentaram uma perda de massa semelhante. No entanto, a queima adicional da caracterização da cerâmica de silicato de lítio reforçado por zircônia favoreceu uma maior perda de massa, sem que houvesse alteração de sua resistência(AU)

The present study aimed to evaluate the behavior of the characterization layer on high translucency zirconia (YZHT, Vita YZ HT), feldspar ceramic (FD / VMII, Vita Mark II) and zirconia reinforced lithium silicate (ZLS, Vita Suprinity) compared to the simulation of physiological wear, varying the antagonists in YZHT, steatite and hybrid ceramic with polymer (Vita Enamic). 120 ceramic discs (ø 12 mm, 1.2 mm thick) were obtained, 30 from YZHT and FD, and 60 from ZLS, by cutting blocks for CAD / CAM. The YZHT samples were sintered, and in the sequence the groups YZHT and FD received the characterization layer. The characterization of the ZLS samples was carried out in the same act of crystallization (ZLS1, single step) or in burning after crystallization (ZLS2, two steps). The characterization was carried out according to the manufacturer's recommendations and all samples received application of glaze and consequent burning. The specimens were divided into subgroups (n = 10) according to the antagonists: steatite, hybrid ceramic or zirconia; then, they were submitted to the simulation of physiological wear. The parameters of average roughness (Ra) and average width of the elements of the roughness profile (Rsm) were analyzed at different moments of the simulation of physiological wear from the beginning to the end of the cycle. After 15,000 cycles, the mass loss of the ceramic discs and antagonistic pistons was calculated. The results were analyzed statistically by Anova 2 factors and Tukey (p <0.05). Before wear, the ceramics showed no differences for the roughness parameters, Ra (p = 0.3348), Rz (p = 0.5590) and Rsm (p = 0.5330). The antagonists showed no differences for the parameters, Ra (p = 0.0541) and Rsm (p = 0.0613), while the parameter Rz (p = 0.000) showed a difference, since steatite (18.98 ± 2) , 98 µm) presented a higher average roughness when the maximum profile height was analyzed when compared with the antagonists in enamic (12.35 ± 0.91 µm) and zirconia (11.47 ± 0.89 µm). After wear, the ceramics continued to show no statistical differences for the roughness parameters, Ra (p = 0.488), Rz (p = 0.681) and Rsm (p = 0.256). The antagonists showed no difference for the Ra parameter (p = 0.124), however, they showed a difference for the Rz parameter (p = 0.000), since steatite (57.98 ± 4.11 µm) showed a higher average for such parameter when compared with antagonists in enamic (44.86 ± 2.34 µm) and zirconia (37.81 ± 1.40 µm); and for the parameter Rsm (p = 0.000), since the averages of steatite (502.72 ± 72.20 µm), enamic (385.67 ± 24.84 µm) and zirconia (268.94 ± 27.99 µm ) showed differences between them. The type of ceramic (p <0.0001) influenced the loss of mass of the samples and the interaction between ceramic and antagonist (p = 0.0098), thereby influencing the loss of mass of the antagonist pistons. The ZLS 2 group showed the greatest loss of mass among the tested groups. All tested antagonists showed similar mass loss against FD, while steatite showed greater mass loss when tested with YHZT, ZLS 1 and ZLS 2 samples. All ceramics showed similar roughness before and after wear simulation. The ceramic samples showed a similar mass loss. However, the additional burning of the characterization of the zirconia-reinforced lithium silicate ceramic favored a greater loss of mass, without altering its strength(AU)

Comportamento biomecânico e sobrevivência de coroas de cerâmica híbrida implantosuportadas confeccionadas por diferentes técnicas / Biomechanical behavior and survival of implant-supported hybrid ceramic crowns made by different techniques

O presente estudo teve como objetivo investigar a probabilidade de sobrevivência e distribuição de tensão de restaurações de cerâmica infiltrada por polímero sobre implantes. Setenta e cinco coroas suportadas por implantes foram divididas de acordo com a técnica de fabricação, usando uma base de titânio(Tibase): CME - Solução protética de duas peças composta por uma coroa cimentada no pilar híbrido (Tibase + mesoestrutura cerâmica); MC - Solução protética de peça única composta por uma coroa cimentada diretamente sobre o Tibase; e MP - Solução protética de peça única composta por uma coroa cimentada em um Tibase com orifício de acesso para parafuso. Todas as coroas foram fadigadas pelo teste stepwise (intervalo de carga de 50 N a cada 20.000 ciclos até 1200 N e 350.000 ciclos). As coroas falhadas foram inspecionadas sob microscopia eletrônica de varredura e a probabilidade de sobrevivência foi analisada usando os testes Log-Rank e Willcoxon. Uma geometria tridimensional de cada grupo foi modelada e analisada pelo método dos elementos finitos. Resultados de deformação total, tensão de von-Misses, tensão principal máxima e microdeformação foram solicitados sob carga axial de 900 N. Log-Rank (p = 0,17) e Willcoxon (p = 0,11) revelaram uma probabilidade de sobrevivência semelhante entre as técnicas de fabricação sob 300 e 900 N. Independentemente da sobrevivência semelhante entre CME e MC, MP mostrou resistência característica superior e menor variação de dados. Maior concentração de tensão foi observada no perfil de emergência da coroa independente do grupo. A fractografia possibilitou identificar que a direção de propagação de trinca ocorreu da cervical para oclusal. É possível concluir que a sobrevivência de uma restauração implanto-suportada com cerâmica vítrea infiltrada por polímero independe da técnica utilizada para sua confecção; e que a região do perfil de emergência da coroa protética sempre deve ser avaliada nas consultas periódicas devido a grande prodominância de falhas nessa área(au)

The present study aimed to investigate the survival probability and the stress distribution of a polymer infiltrate ceramic restorations cemented on a chairside titanium­base manufactured using different techniques. Seventy-five implant-supported crowns were divided according to the manufacturing technique using a chairside titanium­base: CME - Two-piece prosthetic solution composed by a crown cemented on the hybrid abutment; MC - One-piece prosthetic solution composed by a crown direct cemented on a titanium base; and MP - One-piece prosthetic solution composed by a crown cemented on a Tibase with screw access hole. All crowns were staircase fatigued (load step of 50 N in each 20,000 cycles until 1200 N and 350,000 cycles). The failed crowns were inspected under scanning electron microscopy. And the survival probability using Log-Rank and Willcoxon tests. One threedimensional geometry from each group were modeled and analyzed using the finite element method. Results in total deformation, von-Misses stress, maximum principal stress and microstrain were requested under 900 N axial load. Log-Rank (p = 0.17) and Willcoxon (p = 0.11) revealed similar survival probability between the techniques at 300 and 900 N. Regardless of the similar survival between CME and MC, MP showed superior characteristic strength and less data variation. Higher stress concentration was observed in the emergence profile of the crown regardless the group design. Fractography analysis allowed to identify that the crack propagation direction occurred from cervical to occlusal. It is possible to conclude that the survival of an implant-supported restoration with polymer infiltrated ceramic network is not influence by the technique used to make it; and that the emergence profile of the prosthetic crown must always be evaluated due to the great incidence of failures in this area(AU)

Influência da espessura da cerâmica no comportamento biomecânico, sobrevivência e na translucidez de coroas monolíticas / Influence of ceramic thickness on biomechanical behavior, survival and translucency of monolithic crowns

Apesar do aumento do uso de coroas monolíticas, seu desempenho, em diferentes aspectos, ainda não foi determinado. Inicialmente, este projeto investigou o comportamento biomecânico de diferentes coroas monolíticas convencionais sobre dentes e a distribuição de tensões na camada de cimento (Artigo 1). Como objetivo principal, este estudo avaliou o efeito do princípio do mínimo preparo dental no comportamento biomecânico, confiabilidade e translucidez de coroas monolíticas posteriores em cerâmica. No entanto, para definir o substrato a ser utilizado para receber as coroas usinadas, uma análise complementar foi desenvolvida para observar o comportamento da restauração sobre diferentes substratos através da análise por elementos finitos (Artigo 2). E para o Artigo 3, cento e vinte e seis coroas foram fabricadas e divididas (n = 21 / gr) de acordo com o material (zircônia de alta translucidez -YZHT, silicato de lítio reforçado com zircônia - ZLS e cerâmica híbrida -HC) e espessura (0,5 ­ subgrupo .5 ou 1 mm ­ subgrupo 1). A concentração de tensão de tração foi calculada pelo método dos elementos finitos, as coroas adesivamente cimentadas foram fadigadas pelo teste step-stress para calcular a confiabilidade de missões a 600 e 900 N a 100.000 ciclos; e, a translucidez foi analisada em 10 discos de cada material e espessura. Maior concentração de tensão de tração foi observada em coroas mais finas e com módulo de elasticidade mais alto. As coroas YZHT foram suspensas quando a fadiga atingiu a carga de 1.500N, sendo utilizado Weibull 1-parâmetro para analisar os dados. A confiabilidade foi afetada apenas pela espessura em 900 N. ZLS.5 apresentou sobrevida semelhante à HC.5, que foi semelhante aos grupos que apresentaram 100% de sobrevivência. YZHT mostrou a maior resistência característica e dispersão de dados. ZLS1 (22,3 ± 1,4) apresentou maior translucidez que HC1 (19,2 ± 0,6) e YZHT1 (12,0 ± 2,9), enquanto ZLS.5 e HC.5 foram semelhantes (26,5 ± 2,3, 26,7 ± 2,2) e superiores a YZHT.5 (12,7 ± 1,2). O HC.5 combinou alta confiabilidade e translucidez com baixa concentração de tensão, produzindo melhor desempenho da coroa e preservação dos dentes(AU)

Despite the increased use of monolithic crowns, their performance in different aspects has not yet been determined. Initially, this project investigated the biomechanical behavior of different conventional monolithic crowns on teeth and the stress distribution in the cement layer (Article 1). As main purpose, this study evaluated the effect of minimal dental preparation principle on the biomechanical behavior, reliability and translucency of posterior monolithic ceramic crowns. However, to define the substrate to be used to receive the machined crowns, a complementary analysis was developed to observe the restoration behavior on different substrates using the finite element analysis (Article 2). And for Article 3, one-hundred twenty six crowns were divided (n=21/gr) according to the material (High translucent zirconia - YZHT, Zirconia reinforced lithium silicate - ZLS and Hybrid ceramic - HC) and thickness (0.5 or 1 mm). Tensile stress concentration was calculated using the finite element method, the crowns were adhesivelly cemented and step stress fatigued to calculate reliability for missions at 600 and 900 N at 100,000 cycles; and, the translucency was analyzed in 10 discs of each material and thickness. Higher stress concentration was found in thinner crowns and those with higher elastic modulus. YZHT crowns were suspended when fatigue reached 1,500N load, thus 1-parameter Weibull was used to analyse the data. Reliability was only affected by thickness at 900 N. ZLS.5 showed similar survival to HC.5, which was similar to the groups that presented 100% survival. YZHT showed the highest strength and data scattering. ZLS1 (22.3 ± 1.4) presented higher translucency than HC1 (19.2 ± 0.6) and YZHT1 (12.0 ± 2.9), whereas ZLS.5 and HC.5 were similar to each other (26.5 ± 2.3, 26.7 ± 2.2) and superior to YZHT.5 (12.7 ± 1.2). HC.5 combined high reliability and translucency with low stress concentration, yielding better crown performance and tooth preservation(AU)

Ion-releasing dental restorative composites containing functionalized brushite nanoparticles for improved mechanical strength.

OBJECTIVES: This study describes the synthesis of brushite nanoparticles (CaHPO4·2H2O) functionalized with triethylene glycol dimethacrylate (TEGDMA) and their application in dental restorative composites with remineralizing capabilities. METHODS: Nanoparticles were synthesized, with TEGDMA being added to one of the precursor solutions at three different molar ratios (0:1, 0.5:1 and 1:1, in relation to the ammonium phosphate precursor). Then, they were added (10 vol%) to a photocurable dimethacrylate matrix containing 50 vol% of reinforcing glass particles. The resulting composites were tested for degree of conversion, biaxial flexural strength and elastic modulus (after 24h and 28days in water), and ion release (over a 28-day period). Commercial composites (one microhybrid and one microfilled) were tested as controls. RESULTS: The final TEGDMA content in the functionalizing layer was modulated by the molar ratio added to the precursor solution. Functionalization reduced nanoparticle size, but did not reduce agglomeration. Improved mechanical properties were found for the composite containing nanoparticles with higher TEGDMA level in comparison to the composite containing non-functionalized nanoparticles or those with a low TEGDMA level. All brushite composites presented statistically significant reductions in strength after 28 days in water, but only the material with high-TEGDMA nanoparticles retained strength similar to the microhybrid commercial control. Overall, ion release was not affected by functionalization and presented steady levels for 28 days. SIGNIFICANCE: Though agglomeration was not reduced by functionalization, the improvement in the matrix-nanoparticle interface allowed for a stronger material, without compromising its remineralizing potential.

Physical and chemical properties of model composites containing quaternary ammonium methacrylates.

OBJECTIVE: Investigate physical and chemical properties of model composites formulated with quaternary ammonium salt monomers (QAS) at different concentrations and alkyl chains lengths METHODS: QAS with 12 dimethylaminododecyl methacrylate (DMADDM) and 16 dimethylaminohexadecyl methacrylate (DMAHDM) chains lengths were synthesized and incorporated at 5 and 10% in model composites, resulting in four groups: G12.5 (DMADDM 5%), G12.10 (DMADDM 10%), G16.5 (DMAHDM 5%), G16.10 (DMAHDM 10%). One group was used as control group (CG 0%). Degree of conversion (DC); water sorption (WS) and solubility (SL); hygroscopic expansion (HE); degradation temperature (DT); glass transition temperature (Tg) and polymerization shrinkage (PS) were determined. Knoop hardness (KNH), flexural strength (FS) and elastic modulus (EM) were measured before and after storage Data were submitted to ANOVA and Tukey's test (p≤0.05). RESULTS: DC ranged between 76.1 (G12.10) and 70.7 (G16.5) %; CG had the lowest WS, SL and HE. There was no statistical difference for PS and FS. KHN values ranged between 30.2 (GC) and 25 (G16.10) and after storage the performance was depended on QAS concentration and chain length. For EM, CG had the highest values before and after storage and no difference was observed in the QAS groups before storage. After storage, the results were dependent on QAS concentration (3.5-4.3GPa). SIGNIFICANCE: In general, the addition of QAS increased composite's degradation compared with the CG. In the tested QAS, the addition of DMADDM at 5% concentration resulted in a less degradable material.

Novel urethane-based polymer for dental applications with decreased monomer leaching.

The aim of this study was to synthesize and characterize new multifunctional-urethane-methacrylate monomers to be used as the organic matrix in restorative dental composites, and evaluate the main physical-chemical properties of the resulting material. Bis-GMA (bisphenol-A-diglycidylmethacrylate) and GDMA (glycerol dimethacrylate) were modified by reacting the hydroxyl groups with isocyanate groups of urethane-methacrylate precursors to result in the new monomeric systems U-(bis-GMA)-Mod and U-(GDMA)-Mod, U=Urethane and Mod=Modified. The modifications were characterized by FTIR and 1H NMR. The final monomeric synthesized system was used to prepare dental resins and composites. The physical-chemical properties were evaluated and compared with those of bis-GMA composites with varying filler contents or unfilled resins. U-(bis-GMA)-Mod and U-(GDMA)-Mod can be used to prepare dental restorative composites, with some foreseeable advantages compared with bis-GMA composites. One significant advantage is that these composites have the potential to be less toxic, once they presented a reduction of 50% in leaching of unreacted monomers extracted by solvent.

Cytocompatible antifungal acrylic resin containing silver nanoparticles for dentures.

BACKGROUND: Inhibition of Candida albicans on denture resins could play a significant role in preventing the development of denture stomatitis. The safety of a new dental material with antifungal properties was analyzed in this work. METHODS: Poly(methyl methacrylate) [PMMA] discs and PMMA-silver nanoparticle discs were formulated, with the commercial acrylic resin, Nature-Cryl™, used as a control. Silver nanoparticles were synthesized and characterized by ultraviolet-visible spectroscopy, dispersive Raman spectroscopy, and transmission electron microscopy. The antifungal effect was assessed using a luminescent microbial cell viability assay. Biocompatibility tests were carried out using NIH-3T3 mouse embryonic fibroblasts and a Jurkat human lymphocyte cell line. Cells were cultured for 24 or 72 hours in the presence or absence of the polymer formulations and analyzed using three different tests, ie, cellular viability by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and cell proliferation by enzyme-linked immunosorbent assay BrdU, and genomic DNA damage (Comet assay). Finally, the samples were evaluated mechanically, and the polymer-bearing silver nanoparticles were analyzed microscopically to evaluate dispersion of the nanoparticles. RESULTS: The results show that PMMA-silver nanoparticle discs significantly reduce adherence of C. albicans and do not affect metabolism or proliferation. They also appear not to cause genotoxic damage to cells. CONCLUSION: The present work has developed a new biocompatible antifungal PMMA denture base material.

Effects of type I collagen coating on titanium osseointegration: histomorphometric, cellular and molecular analyses.

The investigation of titanium (Ti) surface modifications aiming to increase implant osseointegration is one of the most active research areas in dental implantology. This study was carried out to evaluate the benefits of coating Ti with type I collagen on the osseointegration of dental implants. Acid etched Ti implants (AETi), either untreated or coated with type I collagen (ColTi), were placed in dog mandibles for three and eight weeks for histomorphometric, cellular and molecular evaluations of bone tissue response. While the histological aspects were essentially the same with both implants being surrounded by lamellar bone trabeculae, histomorphometric analysis showed more abundant bone formation in ColTi, mainly at three weeks. Cellular evaluation showed that cells harvested from bone fragments in close contact with ColTi display lower proliferative capacity and higher alkaline phosphatase activity, phenotypic features associated with more differentiated osteoblasts. Confirming these findings, molecular analyses showed that ColTi implants up-regulates the expression of a panel of genes well known as osteoblast markers. Our results present a set of evidences that coating AETi with collagen fastens the osseointegration by stimulating bone formation at the cellular and molecular levels, making this combination of morphological and biochemical modification a promising approach to treat Ti surfaces.

Influence of BisGMA, TEGDMA, and BisEMA contents on viscosity, conversion, and flexural strength of experimental resins and composites.

Different monomer structures lead to different physical and mechanical properties for both the monomers and the polymers. The objective of this study was to determine the influence of the bisphenylglycidyl dimethacrylate (BisGMA) concentration (33, 50 or 66 mol%) and the co-monomer content [triethylene glycol dimethacrylate (TEGDMA), ethoxylated bisphenol-A dimethacrylate (BisEMA), or both in equal parts] on viscosity (eta), degree of conversion (DC), and flexural strength (FS). Eta was measured using a viscometer, DC was obtained by Fourier transfer Raman (FT-Raman) spectroscopy, and FS was determined by three-point bending. At 50 and 66% BisGMA, increases in eta were observed following the partial and total substitution of TEGDMA by BisEMA. For 33% BisGMA, eta increased significantly only when no TEGDMA was present. The DC was influenced by BisGMA content and co-monomer type. Mixtures containing 66% BisGMA showed a lower DC compared with mixtures containing other concentrations of BisGMA. The BisEMA mixtures had a lower DC compared with the TEGDMA mixtures. The FS was influenced by co-monomer content only. BisEMA mixtures presented a statistically lower FS, followed by TEGDMA + BisEMA mixtures, and then by TEGDMA mixtures. Partial or total replacement of TEGDMA by BisEMA increased eta, which was associated with the observed decreases in DC and FS. Although the BisGMA content influenced the DC, it did not affect the FS results.

Effect of the composite surface sealant application moment on marginal sealing of compactable composite resin restoration.

An analysis was carried out to observe whether the application or not of a composite surface sealant (CSS), as well the moment for CSS application were able to reduce marginal microleakage in compactable composite resin restoration. All the preparations were restored with a compactable composite resin. The restored teeth were randomly assessed. G1 (control group): finished and polished; G2: finished, polished, etched and cover with CSS; G3: immediately after the restoration done the CSS was applied, then finished and polished; G4: CSS applied immediately after the restoration was done, the finished and polished, etched, and covered with CSS. The specimens were isolated with nail polish, thermocycled, immersed in aqueous solution of silver nitrate, and followed in a photo developing solution. The microleakage scores obtained from the occlusal and cervical walls were analyzed with the Kruskall-Wallis nonparametric test. No microleakage was found at the enamel margins. Comparing the microleakage scores at dentin/cementum margins (p < 0.05) it was found that G3 (p = 0.0162) and G4 (p = 0.0187) were able to reduce microleakage when compared with group G2. However the results were not statistically different from the control group. The application of CSS was not able to completely eliminate marginal microleakage at the dentin/cementum margins.

RESTAURACION DE DIENTES TEMPORARIOS CON CEMENTO DE VIDRIO IONOMERO-PLATA

El material propuesto contituye una alternativa para la obturación de piezas dentarias temporarias.Por sus caraterísticas de adhesión química a dentina y esmalte, es un exelente sellador marginal, evitando así la microfiltración. Por el desprendimiento de iones de fluor, a largo plazo, a las estructuras del diente, reduce la irrupción de caries marginal, constituyéndose en un material preventivo de caries.El material puede gravarse y así formar una unión con las resinas compuestas. La obturación se realiza en una sóla sesión.Para el manejo del material se precisan de instrumentos especiales