Desensitizing Agent Previously Applied During In-Office Bleaching: A Double-Blind Randomized Clinical Trial

Abstract Objective: To compare the clinical effect of two desensitizing agents used before the application of a bleaching gel based on 35% hydrogen peroxide (HP). Material and Methods: 30 patients were selected, and two desensitizing agents with different mechanisms of action were applied: Fluorine Neutral 2% (FN), which acts by blocking dentinal canaliculi while Potassium Nitrate 5% with 2% Sodium Fluoride (PN/SF) that acts in nerve transmission and blockade. Desensitizers were used before the application of 35% HP. For whitening, three clinical sessions were performed, with an interval of seven days, with three applications of the bleaching gel for 15 minutes, totaling 45 minutes/session. Tooth sensitivity (TS) was assessed with the numerical analog scale, and a spectrophotometer was used to obtain the color variation (ΔE). ΔE were submitted to ANOVA and Tukey test (p<0.05), and TS data were submitted to a two-way ANOVA analysis. Results: For sensitivity experience, the Tukey test indicated differences between PN/SF and the placebo I, but there was no statistically significant difference between FN and the placebo II. The TS was lower when the desensitizing gel was used during the bleaching procedure compared to after treatment, regardless of the desensitizing agents. Conclusion: PN/SF before in-office tooth bleaching can reduce TS intensity, and the use of desensitizing gel before bleaching did not affect the bleaching efficacy.

Reproducibility and comparison between methods for gingival color evaluation: a validation study

Aim This study aims to evaluate and validate the sensibility and the level of agreement between different gingival color measures obtained by a spectrophotometer (SPECTRO) and a photography (PHOTO) method. Methods Among 40 patients, the color was measured 2 mm apical to the gingival margin by CIE L*, a*, b* system using a reflectance spectrophotometer and the photography's plus software. The level of agreement between three different measures (m1, m2, m3) in parameters L*, a*, b*, and ∆E (color variation) was evaluated by random and systematic errors, as well as the limits and coefficient of concordance. A comparison between the methods was performed by the Bland-Altman test and the sensibility level was evaluated accordingly to the ∆E: 3.7 thresholds with p<0.05 as the level of significance for these comparisons. Results The SPECTRO method has not presented the systematic error (p>0.05) and had reproducibly and agreement level in three variable measures L* (r: 0.6), a* (r: 0.3), and b* (r: 0.5) as to the PHOTO method L* (r: 0.6), a* (r: 0.5), and b* (r: 0.5), which presented systematic error in L* values (p<0.05). The means of ∆E between measurements were: 6.5 SPECTRO and 5.9 PHOTO. There was no good level of sensitivity ∆E> 3.7 and agreement between the methods, mainly for the a* values. On the other hand, for the L* and in for the most comparisons of b* values, the level of agreement was higher. Conclusion Both methods could quantify the gingival color from the coordinates L *, a *, and b *, which has shown greater reliability between the measurements acquired by the SPECTRO method.

Qualidade do leite cru refrigerado avaliado por diferentes laboratórios credenciados pelo MAPA / Quality of refrigerated raw milk evaluated by different laboratories accredited by MAPA

O objetivo deste trabalho foi analisar e correlacionar os resultados de qualidade do leite cru refrigerado de dez propriedades rurais de Viçosa (MG) obtidos por métodos de referências do Ministério da Agricultura, Pecuária e Abastecimento e por espectrofotômetros de luz infravermelha em três laboratórios (A, B e C) credenciados pelo mesmo órgão de fiscalização. As amostras de leite foram analisadas quanto à contagem bacteriana, contagem de células somáticas (CCS) e teores de gordura, proteína e extrato seco desengordurado (ESD). Não houve discordância de amostras de leite quanto aos teores de proteína e gordura. Porcentagens diferentes de discordância foram observadas entre os resultados dos laboratórios e método de referência quanto à CCS, contagem bacteriana e teores de ESD. Os teores médios de proteína dos laboratórios A e B e os teores médios de ESD de todos laboratórios não foram estatisticamente iguais (p<0,05) aos teores obtidos pelo método de referência. Os teores de gordura obtidos no laboratório B não tiveram correlação estatística (p>0,05) com os teores obtidos pelo método de referência. Observou-se que as CCS e contagens bacterianas médias de todos os laboratórios foram estatisticamente iguais (p>0,05) e correlacionadas (p<0,05) às contagens médias obtidas pelos métodos de referência. Conclui-se que os teores de proteína em dois laboratórios e ESD em todos os laboratórios não são equivalentes com os métodos de referência do MAPA. É importante que os laboratórios revejam a calibração dos seus equipamentos quanto à quantificação dos teores de sólidos do leite.

The objective of this study was to analyze and to correlate the results of refrigerated raw milk quality in ten farms of Viçosa (MG). The milk was analyzed by the Ministério da Agricultura, Pecuária e Abastecimento standard methods and by infrared spectrophotometers in three laboratories (A, B and C) accredited by the same institution. The milk samples were analyzed for bacterial counts, somatic cell count (SCC) and fat, protein and solids not fat (SNF) tenors. There were no disagreement milk samples as the protein and fat tenors. Different percentages of disagreement were observed between the results of laboratory and standard method as the SCC, bacterial count and SNF tenor. The protein mean tenor of A and B laboratories and the SNF mean tenor of all laboratories were not statistically equal (p<0.05) the tenors obtained by standard method. The fat tenors obtained in B laboratory were not statistically correlated (p>0.05) with tenors obtained by the standard method. It was observed that the means of SCC and bacterial counts of all laboratories were statistically the same (p>0.05) and correlated (p<0.05) to the means counts obtained by standard methods. It is concluded that the protein tenors in two laboratories and SNF in all laboratories are not equivalent with the reference methods of MAPA. It is important that laboratories review the calibration of the equipment on the quantification of milk solids tenors.

Propiedades flexurales y estabilidad de color de materiales restauradores estéticos indirectos / Flexural properties and color stability of indirect esthetic restorative materials

Introducción: Las diferencias en las propiedades mecánicas de los materiales cerámicos y a base de resina plantean la interrogante sobre cuál puede tener un mejor desempeño a largo plazo. Objetivos: Evaluar la resistencia flexural y estabilidad de color de diferentes materiales restauradores estéticos indirectos. Métodos: Los materiales seleccionados fueron Filtek™ Z250 XT (3M ESPE), Ceramage (SHOFU Dental), VITA VM® LC y VITA ENAMIC® (VITA Zahnfabrik), IPS e.max® (Ivoclar-Vivadent) y Zolid FX (Amann Girrbach AG). El ensayo de resistencia flexural (n = 10) fue realizado en una máquina universal de ensayos mecánicos. Las lecturas de color (n = 5) se midieron en un espectrofotómetro VITA Easyshade V®. Resultados: Los materiales totalmente cerámicos mostraron un mejor desempeño mecánico (p < 0,001). Los resultados de estabilidad de color muestran que Ceramage, IPS e.max® y Zolid FX, mostraron una diferencia estadísticamente significativa (p ≤ 0,002) con Filtek Z250 XT, VITA VM® LC y VITA ENAMIC®. Conclusiones: Los materiales totalmente cerámicos presentaron una mayor resistencia flexural y estabilidad de color que los materiales de base polimérica. A pesar de ello, los materiales estéticos indirectos con polímeros en su composición, como Ceramage, se presentan como una alternativa válida, ya que además de tener propiedades mecánicas adecuadas, poseen una estabilidad de color semejante a los materiales cerámicos(AU)

Introduction: Differences in the mechanical properties of ceramic and resin-based materials pose the question of which of the two will perform better in the long run. Objectives: Evaluate the flexural resistance and color stability of different indirect esthetic restorative materials. Methods: The materials selected were Filtek™ Z250 XT (3M ESPE), Ceramage (SHOFU Dental), VITA VM® LC and VITA ENAMIC® (VITA Zahnfabrik), IPS e.max® (Ivoclar-Vivadent) and Zolid FX (Amann Girrbach AG). The flexural resistance assay (n = 10) was conducted in a universal mechanical testing machine. Color readings (n = 5) were taken with a VITA Easyshade V® spectrophotometer. Results: All-ceramic materials had better mechanical performance (p < 0.001). Color stability results show that Ceramage, IPS e.max® and Zolid FX displayed a statistically significant difference (p ≤ 0.002) with respect to Filtek Z250 XT, VITA VM® LC and VITA ENAMIC®. Conclusions: All-ceramic materials exhibited greater flexural resistance and color stability than polymer-based materials. However, indirect esthetic materials with polymers in their composition, such as Ceramage, are presented as a valid alternative, due to their appropriate mechanical properties and their color stability, which is similar to that of ceramic materials(AU)

Color and translucency of repressed lithium disilicate glass ceramic subjected to multiple firings and aging / Cor e translucidez da vitrocerâmica de dissilicato de lítio reprensada submetida a múltiplas queimas e ao envelhecimento

Objetivo: O objetivo deste estudo é avaliar o efeito de múltiplas queimas e envelhecimento na cor e na translucidez da vitrocerâmica de dissilicato de lítio reprensada (IPS e.max press). Material e Métodos: Um total de 42 discos de dissilicato de lítio (15 mm x 1 mm) foram fabricados usando a técnica de prensa térmica seguindo as instruções dos fabricantes. Eles foram divididos em três grupos de acordo com o número de ciclos de prensagem (n=14): Grupo P1 (pressionado uma vez), Grupo P2 (pressionado duas vezes) e Grupo P3 (pressionado três vezes). Cada grupo foi subdividido em dois subgrupos de acordo com o número de ciclos de queima (n=7): Subgrupo (F2): 2 ciclos de queima, Subgrupo (F4): 4 ciclos de queima. Em seguida, todos os corpos de prova foram submetidos à termociclagem. Os parâmetros de cor e translucidez (TP) foram avaliados por espectrofotômetro; após a prensagem, queima (ΔE1: diferença de cor entre prensagem e queima) e envelhecimento (ΔE2: diferença de cor entre prensagem e envelhecimento). Resultados:ΔE1 para o subgrupo F2 (3,38) apresentou menor valor estatisticamente significante do que ΔE1 para o subgrupo F4 (3,94). Após o envelhecimento, o grupo P3 apresentou o maior ΔE2 estatisticamente significante (6,41). Um ΔE2 estatisticamente inferior foi encontrado no grupo P2 (5,55). O grupo P1 apresentou o menor ΔE2 estatisticamente significante (4,28). O TP para o subgrupo F2 (18,27) apresentou valor superior ao subgrupo F4 (17,78). Houve uma diminuição estatisticamente significante no TP após o envelhecimento para todos os grupos testados. Conclusão: O aumento do número de ciclos de queima e de envelhecimento afetaram a cor e a translucidez do dissilicato de lítio reprensado. (AU)

Objective: The aim of this study is to evaluate the effect of multiple firings and aging on color and translucency of repressed lithium disilicate glass ceramic (IPS e.max press). Material and Methods: A total of 42 lithium disilicate discs (15 mm x 1 mm) were fabricated using heat press technique following the manufacturers' instructions. They were divided into three groups according to the number of pressing cycles (n=14): Group P1 (pressed once), Group P2 (pressed twice) and Group P3 (pressed thrice). Each group was subdivided into two subgroups according to the number of firing cycles (n=7): Subgroup (F2): 2 firing cycles, Subgroup (F4): 4 firing cycles. Then all specimens were subjected to thermocycling. Color and translucency parameter (TP) were evaluated by spectrophotometer; after pressing, firing (ΔE1: color difference between pressing and firing) and aging (ΔE2: color difference between pressing and aging). Results:ΔE1 for subgroup F2 (3.38) showed statistically significant lower value than ΔE1 for subgroup F4 (3.94). After aging, group P3 showed the statistically significant highest ΔE2 (6.41). A statistically significant lower ΔE2 was found with group P2 (5.55). Group P1 showed the statistically significant lowest ΔE2 (4.28). TP for subgroup F2 (18.27) showed higher value than subgroup F4 (17.78). There was a statistically significant decrease in TP after aging for all tested groups. Conclusion: Increasing the number of firing cycles and aging affected color and translucency of repressed lithium disilicate. (AU)

Can bulk-fill compromise the curing potential in deep cavities? / Bulkfill pode comprometer o potencial de polimerização em cavidades profundas?

Objective: To determine the effect of the restorative technique, material's opacity and the selected light sources on the curing potential (CP) in deep cavities. Material and Methods: The radiant exitance (mW/cm2) of two light curing units (Bluephase G2 and Radii-Cal) was determined at 0 and 8 mm distance from a power meter sensor (Ophir). Two bulk-fill composites of regular consistency (Opus, FGM; and Filtek One, 3M) and a conventional one (Sirius-Z, DFL) were considered and the level of their opacity were determined by a sphere-based spectrophotometer (SP60, X-Rite). The degree of C=C conversion (DC) was determined by spectroscopy (FTIR-ATR) at 0.05 and 8 mm depths and the CP considered the ratio between them. The "incremental technique" considered 4 increments of 2mm thickness each, whereas the "bulk-fill technique considered 2 increments of 4mm-thickness. Data were submitted to analysis of variance and Tukey's test (95%). Pearson's correlation tests were performed to calculate the possible relation between curing potential and materials' opacity. Results: With the incremental technique it was possible to achieve high CP regardless of the light source. The CP of bulk-fill composites was dependent on the light source, whereas Radii-Cal compromised the DC at 8 mm for both materials. The correlation between opacity and CP was dependent on the light source (r = 0.891707246 for Radii-Cal; r = 0.515703768 for Bluephase G2). Conclusion: The bulk-fill technique was dependent on the light source while the incremental was not. The influence of materials' opacity was dependent on the light curing unit.(AU)

Objetivo: Determinar o efeito da técnica restauradora, a opacidade do material e as fontes de luz selecionadas sobre o potencial de cura (PC) em cavidades profundas. Materiais e métodos: A saída radiante (mW/cm2) de duas unidades de cura por luz (Bluephase G2 e Radii-Cal) foi determinada a 0 e 8 mm de distância de um sensor de potência (Ophir). Dois compósistos bulkfill de consistência regular (Opus, FGM; e Filtek One, 3M) e um convencional (Sirius-Z, DFL) foram considerados e o nível de sua opacidade foi determinado por um espectrofotômetro (SP60, X-Rite). O grau de conversão C=C (DC) foi determinado por espectroscopia (FTIR-ATR) a 0,05 e 8 mm de profundidade e o PC considerou a relação entre eles. A técnica incremental considerou 4 incrementos de 2 mm de espessura cada, enquanto que a técnica bulkfill considerou 2 incrementos de 4 mm de espessura. Os dados foram submetidos à análise de variância e ao teste de Tukey (95%). Os testes de correlação de Pearson foram realizados para calcular a possível relação entre o potencial de cura e a opacidade dos materiais. Resultados: Com a técnica incremental foi possível obter um PC elevado, independentemente da fonte de luz. O PC de compósitos bulkfill foi dependente da fonte de luz, enquanto que Radii-Cal comprometeu o DC em 8 mm para ambos os materiais. A correlação entre opacidade e PC foi dependente da fonte de luz (r = 0,891707246 para Radii-Cal; r = 0,515703768 para Bluephase G2). Conclusão: O potencial de polimerização para a técnica bulkfill foi dependente da fonte de luz, enquanto para a técnica incremental não. A influência da opacidade dos materiais sobre a capacidade de polimerização foi dependente da unidade de fotoativação. (AU)

Cytotoxicity Comparison of a Calcium Silicate-Based Resin Cement versus Conventional Self-Adhesive Resin Cement and a Resin-Modified Glass Ionomer: Cell Viability Analysis

Abstract Objective: To compare the cytotoxicity level of a new calcium silicate-based resin cement (TheraCem) with two commonly used cements, including a conventional self-adhesive resin cement (Panavia SA) and a resinmodified glass ionomer cement (FujiCem2), on the human gingival fibroblast cells after 24 and 48 hours. Material and Methods: Twelve discs of each cement type were fabricated. The extract of cement disks was made by incubating them in the cell medium. Human gingival fibroblast cells were cultured and exposed to cement extracts for 24 h and 48 h. MTT assay was performed on extracts and optical density and cell viability rates were calculated by the spectrophotometer device at 570 nm. Data were analyzed using ANOVA and Tukey HSD tests. Results: The cell viability rates after 24 hours and 48 hours were as follows: TheraCem: 89.24% and 85.46%, Panavia SA: 49.51% and 46.57% and FujiCem2: 50.63% and 47.36%. TheraCem represented the highest cell viability rate. However, no significant difference was noted between Panavia SA and FujiCem2. Time had no significant effect on cell viability. Conclusion: TheraCem exhibited the best results among three tested cements and was considered non-toxic. Panavia SA and FujiCem2 were not significantly different regarding the cell viability rate. Time had no significant effect on the cytotoxicity level of cements (AU).

Dental Whitening: Self-Referred Needs versus Professional Indication

Abstract Objective: To analyze the self-reported need of patients compared to professional indications for tooth whitening. Material and Methods: Initially, 58 undergraduate students responded to a form that highlighted the question: "Do you think you need to have your teeth whitened?" Among those who answered positively to the previous question, ten individuals were photographed with their smiles. In addition, they were asked to point out, on the Vita 3D-Master scale, which color they believed their teeth had, a value that was compared to the actual color obtained by a spectrophotometer. Finally, the photographs were presented to dentists, who were asked about the indication or not of the whitening treatment. Results: Most interviewees (63.8%) self-reported the need for whitening, as well as there was a greater incidence of a positive indication among professionals (53.9%). Pearson's Chi-square test revealed a relationship between patient gender and the training course on the desire to have teeth whitened. Among the professionals, the specialty, as well as time since graduation, interfered in the indication for whitening. Conclusion: Professionals and patients share the aesthetic ideal directly related to light teeth; most patients self-perceive the color of their teeth darker than it actually is; the opinion about the color of the teeth has an extremely subjective character and varies greatly from one professional to another (AU).

The effect of accelerated aging on the color stability and translucency of novel zirconia reinforced rice husk dental composite resin in different infusion media / O efeito do envelhecimento acelerado na estabilidade de cor e translucidez de uma nova resina composta de casca de arroz reforçada com zircônia em diferentes meios de infusão

Objective: To compare the color stability and translucency of aged and unaged experimental zirconia reinforced rice husk nanohybrid composite resin (Zr-Hybrid) with a commercialized nanofilled and a microhybrid composite resin after immersion in four different infusion media. Material and Methods: Three groups of standardized disc-shaped composite resin with 80 samples per group were prepared as follow: Group 1 (Filtek-Z350-XT), Group 2 (Zmack-Comp), and Group 3 (Zr-Hybrid). Each group was further subdivided into aged (n=40) and unaged (n=40) groups. Initial color measurements were taken using a digital spectrophotometer based on CIE L*a*b* color system. Samples in aged subgroup were subjected to 2500 thermal cycles. Subsequently, all samples were immersed in four different types of infusion media (n=10): T1 - Distilled water, T2 - Soft drink, T3 - Tea and T4 - Coffee. After 15 days, color measurements of all samples were measured again. Data were analyzed using two-way ANOVA followed by Bonferroni and paired sample t-tests with a significance level set at P=0.05. Results: Unaged Zr-Hybrid showed comparable color change to Zmack-Comp and Filtek-Z350-XT (P=0.181), but aged Zr-Hybrid demonstrated the lowest color change (P<0.001). Zr-Hybrid exhibited the lowest translucency value (P<0.001), but no significant color and translucency changes (P=0.051 and P=0.069, respectively) were observed between unaged and aged Zr-Hybrid. Soft drink had the greatest effect (P<0.001) on color change, while coffee showed the greatest effect (P<0.001) on translucency. Conclusion: Although Zr-Hybrid showed greater opacity, it still retained its color stability and translucency after accelerated aging compared to commercialized microhybrid and nanofilled composite resins. All infusion media caused discoloration and affected the composite resins' translucency. (AU)

Objetivo: Comparar a estabilidade de cor e translucidez de uma resina composta nanohíbrida de casca de arroz reforçada com zircônia experimental envelhecida e não envelhecida (Zr-Hybrid) com uma resina composta comercial nanoparticulada e microhíbrida após a imersão em quatro meios de infusão diferentes. Material e Métodos: Três grupos de resina composta em forma de disco padronizado com 80 amostras por grupo foram preparados da seguinte forma: Grupo 1 (Filtek-Z350-XT), Grupo 2 (Zmack-Comp) e Grupo 3 (Zr-Hybrid). Cada grupo foi subdividido em grupos de envelhecimento (n = 40) e não envelhecimento (n = 40). As medições iniciais de cor foram feitas usando um espectrofotômetro digital baseado no sistema de cores CIE L * a * b *. As amostras do subgrupo envelhecido foram submetidas a 2500 ciclos térmicos. Posteriormente, todas as amostras foram imersas em quatro tipos diferentes de meios de infusão (n = 10): T1 - Água destilada, T2 - Refrigerante,T3 - Chá e T4 - Café. Após 15 dias, as medições de cor de todas as amostras foram medidas novamente. Os dados foram analisados usando ANOVA dois fatores seguido por Bonferroni e testes t pareados com nível de significância estabelecido em P = 0,05. Resultados: O grupo Zr-Hybrid não envelhecido mostrou uma mudança de cor comparável a Zmack-Comp e Filtek-Z350-XT (P = 0,181), mas o grupo Zr-Hybrid envelhecido demonstrou a menor mudança de cor (P <0,001). Zr-Hybrid exibiu o menor valor de translucidez (P <0,001), mas nenhuma mudança significativa de cor e translucidez (P = 0,051 e P = 0,069, respectivamente) foram observadas entre Zr-Hybrid não envelhecido e envelhecido. O refrigerante teve o maior efeito (P <0,001) na mudança de cor, enquanto o café apresentou o maior efeito (P <0,001) na translucidez. Conclusão: Apesar do grupo Zr-Hybrid tenha mostrado maior opacidade, ele ainda manteve sua estabilidade de cor e translucidez após envelhecimento acelerado em comparação com resinas compostas micro-híbridas e nanoparticuladas comercializadas. Todos os meios de infusão causaram descoloração e afetaram a translucidez das resinas compostas (AU)

Resolução estética de lesões de mancha branca pós-tratamento ortodôntico / Esthetic resolution of white spot lesions after orthodontic treatment

O objetivo deste estudo foi comparar as técnicas de microabrasão de esmalte (ME) e infiltração de resina (IR) em relação à resolução estética de lesões cariosas de mancha branca (LCMB) e avaliar a correlação entre a luminosidade das lesões quando transiluminadas e a resolução do problema (estudo 1); avaliar em um estudo "in vitro", a eficácia do clareamento dental, em amostras de dentes submetidos previamente a IR (estudo 2); avaliar a efetividade do clareamento dental 12 meses após a realização dos protocolos de mínima intervenção, em um estudo de série de casos (estudo 3). Para o estudo 1 foram selecionados 17 pacientes que foram divididos em 2 grupos: ME (N=8) e IR (N=9). Um dente de cada paciente foi fotografado sob condição normal e do mesmo dente com auxilio de dispositivo translume. Em seguida os pacientes foram submetidos às técnicas de mínima intervenção. Após 7 dias de acompanhamento, o mesmo protocolo fotográfico foi realizado. Para resolução estética, foi delimitado a área do dente em relação a área da mancha por software. Para avaliação da cor da mancha quando evidenciada, os valores de luminosidade (L*) das coordenadas L*a*b* foram avaliados antes e após a intervenção, sendo mensurados valores das áreas sadias e área da mancha mais enegrecida. Os dados de correlação foram submetidos ao teste de Person. A resolutividade dos tratamentos foi dada por um Teste t-Student e a diferença de luminosidade antes e após os tratamentos foi dado pelo teste Anova 2 fatores de medidas repetidas (p<0,05). Para o estudo 2, quarenta superfícies de esmalte bovino foram submetidas à desmineralização. Após, foram estabelecidos dois protocolos de manchamento. Vinte espécimes foram imersos em caldo de manchamento por 24 horas (Lab 1) ou 7 dias (Lab 2). Dez corpos-de-prova de cada grupo receberam a aplicação de IR. Todas as amostras foram clareadas com gel de peróxido de carbamida 15% por 14 dias (8 horas diárias). A mensuração da cor foi realizada em espectrofotômetro de refletância em três momentos: inicial, após o manchamento e após o clareamento. Os dados (CIEDE00) foram analisados pelo teste t-Student (p <0,05). Para o estudo 3, foram selecionados 4 voluntários, que tinham LCMB nos dentes anteriores superiores. Os pacientes foram divididos de forma aleatória em dois grupos, sendo estes: ME e IR na área de mancha. Para resolução estética das LCMB, foi determinada a área da mancha em relação a área do dente e a porcentagem da redução pós protocolos. Após 12 meses de acompanhamento, os pacientes receberam clareamento dental, com peróxido de carbamida 10%, durante 21 dias. Os dados do estudo 1 mostram que não houve correlação entre as áreas da mancha (normal e transiluminada) e a resolução estética das mesmas (p>0.05). Em relação a resolutividade, não houve diferença entre os tratamentos (p=0.403). O valor de Luminosidade aumentou após a realização dos procedimentos (p=0.001). Para o estudo 2, nenhuma diferença significativa foi observada no Lab 1 (p=0,560). Para o Lab 2, foram detectadas diferenças significativas (p=0,031). Uma vez que o clareamento foi mais efetivo no grupo não submetido a IR (Lab2). Os resultados do estudo 3 mostram que ambos os protocolos reduziram e/ou suavizaram as áreas das manchas. Após 12 meses de acompanhamento, a técnica de ME apresentou redução no valor da área de mancha. Por fim, o clareamento dental foi efetivo em ambos os protocolos, sem diferenças entre as técnicas. Frente as metodologias propostas, pode-se concluir que: não houve diferenças entre os tratamentos em relação a remoção ou mascaramento das LCMB; a cor das manchas quando transiluminadas não estão relacionadas a resolução estética das mesmas; "in vitro", dentes fortemente manchados, submetidos ao tratamento com RI, o produto parece se comportar como uma barreira semipermeável à penetração do peróxido. Por fim, ambas as técnicas podem ser indicadas para reduzir ou suavizar as áreas de mancha. A ME apresentou redução das áreas de mancha no período avaliado (12 meses). Clinicamente, o clareamento dental pode ser indicado para melhorar a cor dos dentes, independentemente do protocolo pré-estabelecido

The aim of this study was to compare enamel microabrasion (EM) and resin infiltration (RI) techniques in relation to the esthetic resolution of white spot carious lesions (WSL) and to evaluate the correlation between the luminosity of the lesions when transilluminated and the resolution of the problem (study 1); To evaluate in an "in vitro" study, the effectiveness of dental bleaching in samples of teeth previously submitted to RI (study 2); to evaluate the effectiveness of dental bleaching 12 months after the minimal intervention protocols were performed, in a case series study (study 3). For study 1, 17 patients were selected and divided into 2 groups: ME (N=8) and IR (N=9). One tooth from each patient was photographed under normal condition and the same tooth with the aid of a translume device. Then the patients were subjected to the minimal intervention techniques. After 7 days of follow-up, the same photographic protocol was performed. For esthetic resolution, the area of the tooth was delimited in relation to the area of the stain using software. To evaluate the color of the stain when evidenced, the luminosity values (L*) of the coordinates L*a*b* were evaluated before and after the intervention, being measured values of the healthy areas and area of the darker stain. The correlation data were submitted to Person's test. The resolution by the treatments was analyzed by Student's t-test, and the difference in luminosity before and after treatments was analyzed by 2-way repeated measures Anova (p<0.05). For study 2, forty bovine enamel surfaces were subjected to demineralization. Two staining protocols were established. Twenty specimens were immersed in staining broth for 24 hours (Lab 1) or 7 days (Lab 2). Ten specimens from each group received IR application. All specimens were bleached with 15% carbamide peroxide gel for 14 days (8 hours daily). Color measurement was performed by spectrophotometry at three periods: bselien, after staining, and after bleaching. Data (CIEDE00) were analyzed by Student's T test (p <0.05). For study 3, 4 volunteers with WSL in the maxillary teeth were selected. The patients were randomly divided into EM or RI for treating lesions. For esthetic resolution of WSL, the spot area relative to tooth area and the percentage of reduction after protocols were determined. After 12 months of follow-up, the patients received dental bleaching with 10% carbamide peroxide for 21 days. The data from study 1 show that there was no correlation between the stain areas (transilluminated or not) and the esthetic resolution (p>0.05). Regarding resolution, there was no difference between treatments (p=0.403). The Luminosity value increased after the procedures were performed (p=0.001). For study 2, no significant difference was observed in Lab 1 (p=0.560). For Lab 2, significant differences were detected (p=0.031), and whitening was more effective in the group not subjected to IR (Lab2). The results of study 3 show that both protocols reduced and/or softened the areas of the stains. After 12 months of follow-up, the EM technique showed a reduction in the stain area value. Finally, dental bleaching was effective with both protocols, with no differences between the techniques. Based on the proposed methodologies, it can be concluded that: there were no differences between the treatments regarding the removal or masking of WSL; the color of the stains when transilluminated is not related to their esthetic resolution; "in vitro", heavily stained teeth submitted to treatment with RI, the product seems to behave as a semi-permeable barrier to peroxide penetration. Finally, both techniques can be indicated to reduce or soften stained areas. The EM showed a reduction of stained areas in the evaluated period (12 months). Clinically, dental bleaching can be indicated to improve the color of teeth, regardless of the pre-established protocol

In-vitro efficacy of two spectrophotometer-based shade matching systems for color matching of ceramics after artificial accelerated aging / Eficácia in vitro de dois espectrofotômetros baseados em escalas de cor para avaliação de cor de cerâmicas após envelhecimento artificial acelerado

Objective: The objective of the present in-vitro study was to verify the efficacy of two spectrophotometer-based shade matching systems for color matching of ceramics after artificial accelerated aging (AAA). Material and Methods: The ceramics used were porcelain laminated veneers. Seventy standard-shaped discs (thickness x diameter: 0.5 mm x 10 mm) of B1 shades were used. Based upon the type of resin cement used, the specimens were divided into seven groups (10/group). The following light-cured cements were used: RelyX-Veneer (L-RV), Variolink-Veneer (L-VV), and Variolink-Esthetic (L-VE). The dual-cured cements were: RelyX Ultimate (D-RU), RelyX-Unicem (D-RC), and Variolink-Esthetics DC (D-VE). The control group consisted of ceramic only. All specimens were thermocycled in water for 3,500 cycles between 5 oC -55 oC, with dwell times of 30 s in each bath and a transfer time of 10 s between baths. All specimens were thermocycled in water for 3,500 cycles between 5 oC and 55 oC, and color measurement was done using the VITA Easyshade and ColorEye spectrophotometers. Baseline color reading was performed 24-hours after cementation. Differences in color (DE) of EasyShade and ColorEye before and after AAA were determined and compared statistically. Group comparisons were done using the paired t-tests. Level of significance was set at P< 0.05. Results: The mean differences in color (ΔE) values obtained from EasyShade spectrophotometer for light- and dual-cured cements, were 0.843±0.89 (L-RV ), 4.11±0.69 (L-VV) and 0.833±0.47 (L-VE); and 2.22±0.64 (D-RU), 3.37±0.83 (D-RC) and 0.38±0.92 (D-VE), respectively. The mean differences in color (ΔE) values obtained from ColorEye spectrophotometer for light- and dual-cured cements, were 0.68±0.86 (L-RV ), 4.55±0.83 (L-VV) and 2.68±0.26 (L-VE); and 2.06±0.84 (D-RU), 1.8±1.08 (D-RC) and 0.96±0.71 (D-VE), respectively. There was no significant difference in the mean DE values among the groups. Conclusion: The VITA Easyshade and ColorEye shade matching systems are comparable in terms of their efficacy for color matching of cerammics after AAA.(AU)

Objetivos: O objetivo do presente estudo in vitro foi verificar a eficácia de dois espectrofotômetros baseados em escalas de cor para avaliação de cor de cerâmicas após envelhecimento artificial acelerado (EAA). Material e Métodos: As cerâmicas utilizadas foram laminados cerâmicos. Foram usados setenta discos de formato padrão (0,5mm de espessura x 10 mm de diâmetro) de tonalidades B1. Com base no tipo de cimento resinoso utilizado, os corpos-de-prova foram divididos em sete grupos (10 / grupo). Foram utilizados os seguintes cimentos fotopolimerizáveis: RelyX-Veneer (L-RV), Variolink-Veneer (L-VV) e Variolink-Esthetic (L-VE). Os cimentos de cura dual foram: RelyX Ultimate (D-RU), RelyX-Unicem (D-RC) e Variolink-Esthetics DC (D-VE). O grupo controle consistia apenas de cerâmica. Todos os corpos-de-prova foram termociclados em água por 3.500 ciclos entre 5oC-55oC, com tempos de permanência de 30s em cada banho e um tempo de transferência de 10s entre os banhos. A medição da cor foi feita usando os espectrofotômetros VITA Easyshade e ColorEye. A leitura da cor inicial foi realizada 24 horas após a cimentação. As diferenças na cor (ΔE) do EasyShade e ColorEye antes e depois do EAA foram determinadas e comparadas estatisticamente. As comparações dos grupos foram feitas usando o teste t pareados. O nível de significância foi estabelecido em p <0,05. Resultados: os valores médios de diferenças na cor (ΔE) obtidos no espectrofotômetro EasyShade para cimentos fotopolimerizáveis e duais foram de 0,843 ± 0,89 (L-RV), 4,11 ± 0,69 (L-VV) e 0,833 ± 0,47 (L-VE ); e 2,22 ± 0,64 (D-RU), 3,37 ± 0,83 (D-RC) e 0,38 ± 0,92 (D-VE), respectivamente. os valores médios de diferenças na cor (ΔE) obtidos no espectrofotômetro ColorEye para cimentos fotopolimerizáveis e duais foram de 0,68 ± 0,86 (L-RV), 4,55 ± 0,83 (L-VV) e 2,68 ± 0,26 (L-VE); e 2,06 ± 0,84 (D-RU), 1,8 ± 1,08 (D-RC) e 0,96 ± 0,71 (D-VE), respectivamente. Não houve diferença significativa nos valores médios de ΔE entre os grupos. Conclusão: Os sistemas de combinação de cores VITA Easyshade e ColorEye são comparáveis em termos de eficácia para avaliação de cores de cerâmicas após EAA. (AU)

Effect of varying thickness and artificial aging on color and translucency of cubic zirconia and lithium disilicate ceramics / Efeito da variação da espessura e do envelhecimento artificial na cor e translucidez de cerâmicas de zircônia cúbica e dissilicato de lítio

Objective: The aim of this study is to evaluate the effect of varying thickness and artificial aging on the color and translucency of cubic zirconia and lithium disilicate ceramics. Material and Methods: A total of 30 square shaped disks (12 mm x 12 mm) were fabricated from the cubic zirconia (Bruxzir Anterior) blank and lithium disilicate blocks (E.max CAD), used in three thicknesses (0.5mm, 0.8mm and 1mm). Portable spectrophotometer Vita Easyshade Advance was used to obtain color coordinates, which were substituted in formulas and used to calculate color change and translucency parameter values before and after aging (thermocycling for lithium disilicate and hydrothermal aging for cubic zirconia). Repeated measures Analysis of Variance (ANOVA) was used to study the effect of ceramic type, thickness, aging and their interaction on mean translucency parameter. Two-way (ANOVA) was used to study the effect of ceramic type, thickness and their interaction on mean color change (ΔE). Results: Statistical analysis showed that E.max CAD HT is more translucent than Bruxzir Anterior. Translucency decreased as thickness increased. There was a statistically significant decrease in TP after aging for both materials. Lithium disilicate showed statistically significant greater ΔE when subjected to aging than cubic zirconia, with both ΔE values being clinically imperceptible. As thickness increased, ΔE decreased. Conclusions: Thickness highly affected translucency and color of ceramics. As thickness increases, translucency parameter decreases and color change becomes less evident. Aging also causes a significant decrease in translucency parameter and induces color change however color changes are imperceptible. (AU)

Objetivo: O objetivo deste estudo é avaliar o efeito de diferentes espessuras e do envelhecimento artificial na cor e translucidez de cerâmicas de zircônia cúbica e dissilicato de lítio. Material e Métodos: Um total de 30 discos (12 mm x 12 mm) foram fabricados a partir de um bloco branco de zircônia cúbica (Bruxzir Anterior) e blocos de dissilicato de lítio (E.max CAD) em três diferentes espessuras (0,5mm, 0,8mm e 1mm). Um espectrofotômetro portátil Vita Easyshade Advance foi utilizado para obter as coordenadas de cores, que foram substituídas nas fórmulas e usadas para calcular os valores dos parâmetros de mudança de cor e translucidez antes e depois do processo de envelhecimento (termo ciclagem para dissilicato de lítio e envelhecimento hidrotérmico para zircônia cúbica). A análise de variância de medidas repetidas (ANOVA) foi usada para estudar o efeito do tipo de cerâmica, a espessura, o envelhecimento e a sua interação no parâmetro de translucidez média. Two-way (ANOVA) foi usado para estudar o efeito do tipo da cerâmica, espessura e sua interação na alteração de cor média (ΔE). Resultados: a análise estatística mostrou que a cerâmica E.max CAD HT é mais translúcida que Bruxzir Anterior. A translucidez diminuiu com o aumento da espessura. Houve uma diminuição estatisticamente relevante no TP após o envelhecimento para ambos os materiais. O dissilicato de lítio apresentou maior ΔE estatisticamente relevante quando submetido ao envelhecimento quando comparado com a zircônia cúbica, sendo ambos os valores de ΔE clinicamente imperceptíveis. Conforme a espessura aumentou, o ΔE diminuiu. Conclusão: a espessura afetou expressivamente na translucidez e cor das cerâmicas. À medida que a espessura aumentou, os parâmetros de translucidez diminuíram e a mudança de coloração se tornou menos evidente. O envelhecimento também causou uma diminuição significativa no parâmetro de translucidez das cerâmicas de zircônia cúbica e dissilicato de lítio. (AU)

Clinical Evaluation of 6-Month Efficacy of 40% in-Office Whitening Treatment

ABSTRACT Objective: To assess the 6-month efficacy of natural tooth color change in in-office bleaching treatment in terms of time by using a spectrophotometer. Material and Methods: A total of 20 participants were chairside treated with 40% hydrogen peroxide (HP), three applications each 20 minutes, in one appointment. Instrumental color measurement was performed on six anterior maxillary teeth before bleaching (baseline-t0), immediately after in-office bleaching and rehydration of the teeth (t1), 3 months (t2), and 6 months after bleaching treatment (t3). The spectrophotometer measured the tooth shades based on the CIE L*a*b* color notation system and Bleach index during the period of observation. CIE L*a*b* (ΔEab) color differences were calculated. Results: The color change at t1 was ΔEab = 3.2, at t2 was ΔEab = 1.8, at t3 was ΔEab = 1.2 and overall color change of in-office method was ΔEab = 3.6 (p<0.05). A significant effect for the mean CIEL*a*b* values was detected as within time b* values decreased significantly (p<0.05). Bleach index values significantly decreased during the time of observation, too (p<0.05). Conclusion: The in-office bleaching treatment using 40% hydrogen peroxide was effective, and the results showed a statistically significant decrease in color change during the period of 6-month observation.

Effect of pigmenting agents on tooth enamel staining during immediate tooth whitening: an in vitro study / Efeito de agentes pigmentantes no manchamento do esmalte dental durante o clareamento dentário imediato: estudo in vitro

Introduction: Considering the increased search for esthetic procedures, questions emerge about the maintenance and regression of color, especially regarding the need to restrict dark foods during bleaching procedures or their influence on the stability and effectiveness of the treatment. Objective: To assess the influence of staining agents on tooth enamel during immediate bleaching treatment with 35% hydrogen peroxide. Material and method: Sixty bovine teeth were divided into six groups (G) (n=10): G1: distilled water (control); G2: coffee; G3: cola soft drink; G4: wine; G5: mate tea; and G6: industrialized açaí. The samples were subjected to immediate bleaching using 35% hydrogen peroxide for 21 days (three applications of 15 minutes per session, every seven days) and pigment immersion between each session for 15 minutes. The color was assessed before starting bleaching and after 21 days, using a spectrophotometer. The data obtained were subjected to one-way ANOVA and heteroscedasticity analysis by the Welch and Brown-Forsythe tests. The Tamhane test was used for group comparison. Result: The color change was visible to the naked eye, considering the mean ΔE in all groups tested was higher than 3.7. However, there was no statistical difference between the control group and the groups assessed. Conclusion: The contact of staining agents on bovine tooth enamel did not affect the final result of the immediate tooth bleaching.

Introdução: Com o aumento da procura por procedimentos estéticos, dúvidas surgem quanto à manutenção e regressão de cor, especialmente, no que tange a necessidade de restrição quanto à alimentos escuros durante o procedimento clareador ou a sua influência quanto à estabilidade e eficácia do tratamento. Objetivo: Avaliar a influência de agentes pigmentantes sobre o esmalte dental durante o tratamento clareador imediato com peróxido de hidrogênio a 35%. Material e método: 60 dentes bovinos foram divididos em 6 grupos (G) (n=10): G1: água destilada (controle), G2: café, G3: refrigerante à base de cola, G4: vinho, G5: chá-mate, e G6: açaí industrializado. As amostras foram submetidas ao clareamento imediato utilizando peróxido de hidrogênio a 35% durante 21 dias (3 aplicações de 15 minutos por sessão a cada 7 dias) e submetidas à imersão dos pigmentos entre cada sessão durante 15 minutos. A avaliação da cor foi realizada antes do inicio do clareamento e após 21 dias, mediante o uso do espectrofotômetro. Os dados obtidos foram submetidos ao ANOVA one-way e análise de heterocedasticidade pelos testes de Welch e Brown-Forsythe. O teste de Tamhane foi utilizado para a comparação entre os grupos. Resultado: Houve alteração de cor visível ao olho nu, uma vez que a média de ΔE em todos os grupos testados foi maior que 3,7. Contudo, não houve diferença estatística entre o grupo controle em relação aos grupos avaliados. Conclusão: O contato de agentes pigmentantes no esmalte dental bovino não influenciou o resultado final do clareamento dental imediato.

Analysis of the Total Level of Flavonoids in the Brown Algae ( Phaeophyceae ) Extract as Analgesic and Anti-Inflammatory Drugs

Abstract Objective: To determine the total level of flavonoids in brown algae extract Padina sp., Sargassum sp., and Turbinaria sp., which could serve as an analgesic and anti-inflammatory drug. Material and Methods: This is an experimental study with a one-shot case study research design. The study sample consisted of three species of brown algae, namely, Padina sp., Sargassum sp., and Turbinaria sp. The study samples were obtained from Saugi Island, Pangkep, Regency. The sampling method used was convenience sampling. The total flavonoid level in the three extracts of brown algae samples was determined at three concentrations (150 ppm, 300 ppm, and 450 ppm) with three replicates. The analysis used a colorimetric method, a spectrophotometer and aluminium chloride as the reagent. Results: The total level of flavonoids in Padina sp. was the highest at 0.894 ± 0.027%, compared to the levels of 0.786 ± 0.075% in Sargassum sp. and 0.745 ± 0.016% in Turbinaria sp. Conclusion: Padina sp. had the highest total flavonoid levels compared to Sargassum sp. and Turbinaria sp. Flavonoid compounds from brown algae have the potential to be used as analgesic and anti-inflammatory drugs.

Biologically Synthesized Silver Nanoparticles for Enhancing Tetracycline Activity Against Staphylococcus aureus and Klebsiella pneumoniae

Abstract Phytochemical content of plant extracts can be used effectively to reduce the metal ions to nanoparticles in one-step green synthesis process. In this study, six plant extracts were used for the synthesis of silver nanoparticles (AgNPs). Biologically synthesized AgNPs was characterized using UV-Vis Spectrophotometer, Field Emission Scanning Electron Microscope (FE-SEM), X-ray diffraction (XRD), Energy Dispersive X-ray spectroscopy (EDX) and Fourier Transform Infrared (FTIR) spectroscopy. The individual and combined effects of AgNPs and tetracycline against S. aureus and K. pneumoniae were assessed. Ginger, onion and sidr extracts supported AgNPs formation while arak, garlic and mint extracts failed to convert the silver ions to AgNPs. The present findings revealed significant differences between the tested plant extracts in supporting AgNPs synthesis. AgNPs synthesized by ginger showed the highest individual and combined activity against tested strains followed by AgNPs prepared by sidr then that synthesized by onion. AgNPs significantly enhanced tetracycline activity (p≤0.05) against S. aureus and K. pneumoniae. The results of this study demonstrated that the combination of tetracycline and biologically synthesized AgNPs presented a useful therapeutically method for the treatment of bacterial infection and counterattacking bacterial resistance.

The effect of different surface treatments on color and translucency of bilayered translucent nano-crystalline zirconia before and after accelerated aging / O efeito de diferentes tratamentos de superfície na cor e translucidez da zircônia de dupla camada nano-cristalina translúcida antes e depois do envelhecimento

Objective: Despite the higher translucency of nanocrystalline Y-TZP than the conventional Y-TZP, it couldn't be used in the anterior region of the mouth in its fully anatomical form without veneering for better esthetics. This study evaluated the color change (ΔE) and translucency parameter (TP) of the bilayered nano-crystalline zirconia restorations after different treatments of the zirconia surface before and after accelerated aging. Material and Methods: Forty samples of inCoris TZI were cut in the form of discs 15 mm (diameter) and 1mm (thickness) so that after sintering each disc dimensions' would be 12 mm (diameter) and 0.8 mm (thickness). All discs were colored by dipping in aqueous zirconia coloring solution of shade A2, then divided into four groups according to the type of surface treatment received before sintering; being tribochemical silica coating, zirconia powder deposition, glass grading, and a control untreated group. After sintering, all discs were veneered with a layer of porcelain 0.7 mm (thickness) and 12 mm (diameter). (ΔE) and TP were measured using VITA Easyshade Compact spectrophotometer before and after accelerated autoclave aging. Results: Different surface treatments applied had significant effect (P<0.05) over ΔE and TP. Glass graded group showed the highest ΔE value and the least TP value among both un-aged and aged sub-groups. Conclusion: Different surface treatments applied affected the color and translucency negatively where the control untreated group showed the highest TP and the least color deviation from the A2 color parameters. On the other hand, accelerated autoclave aging had no effect over translucency or color. (AU)

Objetivo: Apesar da maior translucidez da Y-TZP nanocristalina em relação à Y-TZP convencional, ela não pode ser usada na região anterior da boca em sua forma totalmente anatômica, sem o recobrimento cerâmico para uma melhor estética. Este estudo avaliou a mudança de cor (ΔE)eoparâmetrodetranslucidez(PT)das restauraçõesde zircônia nano-cristalina em duas camadas após diferentes tratamentos de superfície, antes e após o envelhecimento. Material e Métodos: Quarenta amostras de inCoris TZI foram cortadas na forma de discos de 15 mm (diâmetro) e 1 mm (espessura) para que, após sinterização, cada diâmetro dos discos fosse de 12 mm (diâmetro) e 0,8 mm (espessura). Todos os discos foram corados por imersão em solução aquosa de zircônia corante da sombra A2, divididos em quatro grupos de acordo com o tipo de tratamento de superfície recebido antes da sinterização; sendo revestimento de sílica químico-química, deposição de pó de zircônia, jateamento de vidro e um grupo de controle sem tratamento. Após a sinterização, todos os discos foram revestidos com uma camada de porcelana de 0,7 mm (espessura) e 12 mm (diâmetro). ΔE e TP foram medidos usando o espectrofotômetro VITA Easyshade Compact antes e depois do envelhecimento em autoclave. Resultados: Diferentes tratamentos de superfície aplicados tiveram efeito significativo (P <0,05) sobre ΔE o e maior TP. valor O grupo com de ∆E e o menor jateamento de vidro valor de TP apresentou entre os subgrupos não envelhecidos e envelhecidos. Conclusão: Diferentes tratamentos de superfície aplicados afetaram negativamente a cor e a translucidez, onde o grupo controle sem tratamento apresentou o maior TP e o menor desvio de cor dos parâmetros de coloração A2. Por outro lado, o envelhecimento acelerado da autoclave não teve efeito sobre a translucidez ou a cor. (AU)

The effect of a bleaching agent on the pigment removal and the bond strength of bulk-fill resin composites: an in vitro study / Efeito dos agentes clareadores na remoção de pigmentos e na resistência de união de resinas compostas bulk-fill: um estudo in vitro

Introduction: In order to simplify the technique, reduce the time required for direct adhesive restorations, bulk-fill resin composites have been developed be applied in bulk placement up to 4 mm increments. Objective: Evaluating the color change (ΔE) and the microtensile bond strength (μTBS) of bulk fill resin composites (BFRC) to dentin after the immersion in regular beverages and the application of bleaching systems. Method: Forty-five human molar teeth were randomly distributed in three groups according to the filling material (n=15): Filtek Bulk Fill, Tetric N Ceram Bulk Fill and Filtek Z100. The restored teeth were immersed in coffee, wine and distilled water (n=5) for 72 hours. The color parameters were measured using a spectrophotometer, having as basis the CIE L*a*b*, before and after tooth staining and application of bleaching processes. Subsequently, the teeth were sectioned to obtain the specimens for the microtensile testing. The ΔE values were analyzed applying the Kruskal-Wallis and the Wilcoxon tests, and the μTBS values were analyzed applying the ANOVA and the Bonferroni tests (p<0.05). Result: There were no significant differences in the ∆E values when comparing the BFRCs to the conventional resin composite (CRC) in most of the experimental groups. The ∆E values did not present significant differences before and after the application of bleaching processes for all the tested resin composites. The BFRCs presented higher μTBS values than the CRC after exposure to distilled water, wine and bleaching agent. Conclusion: The studied BFRCs presented similar color stability to the CRC. The BFRCs presented higher bond strength to the dentin than the CTC in most of the evaluated conditions. The bleaching agent was not effective in whitening the stained restored teeth.

Introdução: Em busca de simplificar a técnica, reduzir o tempo requerido para as restaurações adesivas, resinas compostas bulk-fill (RCBF) estão sendo desenvolvidas para serem aplicadas em incrementos com espessura de até 4 mm. Objetivo: Avaliar a alteração de cor (ΔE) e resistência de união (μTBS) de RCBF a dentina após imersão em bebidas e aplicação de um sistema clareador. Método: Foram utilizados 45 dentes molares humanos que foram distribuídos aleatoriamente em três grupos de acordo com o material restaurador (n=15): Filtek Bulk Fill, Tetric N Ceram Bulk Fill e Filtek Z100. Os dentes restaurados foram imersos em café, vinho e água destilada (n=5) durante 72 horas. Os parâmetros de cor foram mensurados utilizando um espectrofotômetro, tendo como base o CIE L*a*b*, antes e após o manchamento e aplicação dos agentes clareadores. Consequentemente, os dentes foram seccionados para a obtenção de espécimes para o teste de microtração. Os valores de ΔE foram analisados aplicando os testes de Kruskal-Wallis e Wilcoxon e os valores de μTBS foram analisados aplicando ANOVA e o teste de Bonferroni (p<0,05). Resultado: Não houve diferença significante nos valores de ∆E quando as RCBFs foram comparadas a resina composta convencional (RCC) na maioria dos grupos experimentais. Os valores de ∆E não apresentaram diferença estatística antes e após a aplicação do agente clareador para todas as resinas testadas. As RCBFs demonstraram maiores valores de μTBS comparado a RCC após exposição a água destilada, vinho e agente clareador. Conclusão: As RCBFs demonstraram uma similar estabilidade de cor quando comparado a RCC. As RCBFs apresentaram maior resistência de união a dentina que a RCC na maioria das condições avaliadas. O agente clareador não foi efetivo no clareamento dos dentes restaurados.

Color evaluation of a resin cement light polymerized by different light sources and submitted to potentially staining beverages / Avaliação da cor de um cimento resinoso fotopolimerizado por diferentes fontes de luz e submetidos a bebidas potencialmente corantes

Introduction: The color stability of resin cements, whether dual-pre-cured or photopolymerizable, as well as the color of the dental substrate, are fundamental for the aesthetic success of ceramic restorations, since the ceramic presents a high level of translucency due to its small thickness. Objective: The aim of this in vitro study was to evaluate the color of a resin cement light polymerized by different light sources and immersed in potentially staining beverages. Material and method: Were made 42 specimens of resin cement Variolink-Esthetic (2×6mm) (n=7), being half polymerized with LED light (F1) and half with Halogen light (F2). The specimens were stored in artificial saliva at 37 °C±1 °C. After 24 hours, they were polished with abrasive discs, and divided for the purpose of being submitted to the different solutions for 2 minutes per day, for 28 days, as follows: S1 - Coca-Cola; S2 - Red Wine; and S3 - Distilled Water (Control). Five color readouts were taken: T0 - initial; T1 - 7 days; T2 - 14 days; T3 - 21 days; and T4 - 28 days; with a spectrophotometer (Model SP62S). The color change data (ΔE*) were submitted to statistical analysis, ANOVA and Tukey (p≤0.05). Result: Analyzing the factor solution, S2 (5.89 (±0.02)), produced a higher ΔE* value than S1 (3.79 (±0.02)) and (S1), a higher value than S3 (1.41 (±0.02)). Analyzing the factor light source, F2 (4.05 (±0.12)), produced a higher ΔE* value than F1 (3.33 (±0.12)). When analyzing the factor time, ΔE* values were found to increase gradually over the course of time: T1(2.36 (±0.08)); T2(3.27 (±0.08)); T3(4.06 (±0.08)); and T4(5.09 (±0.08)). Conclusion: It was concluded that red wine produced a greater color change; Halogen light promoted highest degree of pigmentation; and the longer the time of immersion, the greater the color change of the material.

Introdução: A estabilidade de cor dos cimentos resinosos, sejam eles de presa dual ou fotopolimerizáveis, assim como a cor do substrato dental, são fundamentais para o sucesso estético das restaurações cerâmicas uma vez que a cerâmica apresenta alto nível de translucidez devido a sua pequena espessura. Objetivo: O objetivo deste estudo in vitro foi avaliar a cor de um cimento resinoso fotopolimerizado por diferentes fontes de luz e imersos em bebidas potencialmente corantes. Material e método: Foram confeccionados 42 espécimes do cimento resinoso Variolink-Esthetic (2×6mm) (n=7), sendo metade fotopolimerizado com luz LED (F1) e metade com luz Halógena (F2). Os espécimes foram mantidos em saliva artificial à 37 °C±1 °C. Após 24 horas, foram polidos com discos abrasivos e subdivididos para serem imersos 2 minutos por dia, durante 28 dias, nas diferentes soluções: S1 - Coca-Cola; S2 - Vinho Tinto; e S3 - Água destilada (controle). Foram realizadas 5 leituras de cor: T0 - inicial; T1 - 7 dias; T2 - 14 dias; T3 - 21 dias; e T4 - 28 dias; com auxílio de um espectrofotômetro (modelo SP62S). Os dados de alteração de cor (ΔE*) foram submetidos a análise estatística, ANOVA e Tukey (p≤0,05). Resultado: Analisando o fator solução, S2 (5,89 (±0,02)), proporcionou maior ΔE* que S1 (3,79 (±0,02)) e este (S1), maior que S3 (1,41 (±0,02)). Analisando o fator fonte de luz, F2 (4,05 (±0,12)), proporcionou maior ΔE* que F1 (3,33 (±0,12)). E analisando o fator tempo, obteve-se que ΔE* foi gradativamente aumentando no decorrer do tempo: T1(2,36 (±0,08)); T2(3,27 (±0,08)); T3(4,06 (±0,08)); e T4(5,09 (±0,08)). Conclusão: Conclui-se que o vinho tinto promoveu maior alteração de cor; a luz Halógena promoveu maior pigmentação e; quanto maior o tempo de imersão, maior alteração de cor do material.

Avaliação do efeito cromático em resinas compostas nanoparticuladas submetidas a solução café / Two nanoparticulate composite resins chromatic effect evaluation submitted to coffee solution

Introdução: Em uma sociedade de alta competitividade social, os padrões estéticos estão cada vez mais refinados e, dentro destes, a concepção e o desejo de se ter o sorriso perfeito aumentaram consideravelmente a busca pelos tratamentos dentários e, consequentemente, o desenvolvimento de materiais que possam propiciar tais resultados. O sucesso clínico de uma restauração engloba sua longevidade, do ponto de vista funcional, incluindo ausência de infiltrações, e sua função estética, por meio da manutenção de coloração e lisura superficial adequada. Objetivo: O presente trabalho busca analisar a alteração de cor de duas marcas de compósitos odontológicos nanoparticulados ‒ Z350 e Bulk Fill (3M ESPE) ‒ e dois sistemas de polimento ‒ Disco SofLex e Disco SofLex espiral emborrachado (3M ESPE) ‒, com as subdivisões em grupos controle (água destilada) e experimental (café), em um período de 21 dias. Material e método: Os espécimes foram confeccionados de modo padronizado e armazenados por sete dias em água deionizada a 37 °C, em estufa para análise da cor inicial, seguido do armazenamento nas respectivas soluções para a análise cromática, ao final do período de estudo, sendo ambas as análises realizadas através de espectrofotômetro (CM-700d, Konica Minolta, Osaka, Japão) e escala ΔE CIELAB. Resultado: Observou-se que ambas as resinas tiveram sua coloração alterada na presença do café, entretanto a resina Z350 apresentou maiores variações em comparação à Bulk Fill. Conclusão: Apesar de a solução corante café ser capaz de promover mudança de cor nas resinas estudadas, os sistemas de polimento, isoladamente, não apresentam efeito final sobre a alteração cromática desses materiais restauradores.

Introduction: In a highly social competitive society, aesthetic standards are increasingly refined as the conception and desire of a perfect smile considerably increased the search for dental treatment, with the developing of materials that could propitiate those results. Restorations clinical success includes its longevity, from the functional point of view, with no infiltrations, and aesthetic, through the color conservation and proper surface smoothness. Aim: This work analyzes the color change of two nanoparticulate resins: Z350 and Bulk Fill (3M ESPE) and two polishing systems: SofLex Disk and rubber spiral SofLex Disk (3M ESPE), divided in control group (deionized water) and experimental group (coffe), during 21 days. Material and method: The resin discs were prepared by a standardized mode and submerged in deionized water for 7 days at 37 °C in incubator before initial color evaluation, followed by the immersion in each solution to final color analysis. Both used a spectrophotometer (CM-700d, Konica Minolta, Osaka, Japan) and ΔE CIELAB scale. Result: It was seen that both resins presented color change when exposed to coffee, however the Z350 resin presented a greater variation compared to Bulk Fill resin. Conclusion: Although coffee is a dye solution, the polishing systems did not present any effect on chromatic alteration.