Effects of lesion size on the 30-month clinical performance of restorations with bulk fill and a regular nanofilled resin composite in noncarious cervical lesions.

OBJECTIVE: The aim of this double-blind, randomized trial was to evaluate the influence of the occlusogingival distance (OGD) in noncarious cervical lesions (NCCLs) on the clinical performance of a regular bulk-fill resin composite and a regular nanofilled resin composite. MATERIALS AND METHODS: One hundred and forty NCCLs in 77 participants were randomly divided into four groups (n = 35), according to OGD (1.5 mm ± 10% or 3 mm ± 10%) and resin composites (Filtek Bulk Fill Posterior [B] or Filtek Z350 XT [C]), namely: 1.5 mm-B, 1.5 mm-C, 3 mm-B, and 3 mm-C. The restorations were bonded using a two-step self-etch adhesive (Clearfil SE Bond), applied following the manufacturer's instructions. Restorations were polished 1 week after placement. Two experienced and calibrated examiners evaluated the restorations using modified US Public Health Service criteria at baseline (7 days) and after 6, 12, 18, 24, and 30 months. Statistical analyses were carried out using Kruskal-Wallis, Friedman's repeated measures analysis of variance, and the Wilcoxon signed rank test (α = 0.05). RESULTS: After 30 months, the recall rate was 94.2%. Eight restorations were lost (3 for 1.5 mm-C, 2 for 1.5 mm-B, 1 for 3 mm-C, and 2 for 3 mm-B). All groups resulted in a significantly worse marginal discoloration and surface texture at 30 months in comparison with the baseline (1 week). No significant difference was found for the other parameters. CONCLUSION: The restorations performed with both resin composites produced clinically acceptable restorations. The OGD of NCCLs did not influence the clinical performance of restorations. CLINICAL SIGNIFICANCE: The OGD of NCCLs did not have a significant effect on the clinical performance of a regular bulk-fill and nanofilled restorations. Both materials showed a very good performance on 30-month evaluation.

In vitro effectiveness of different dental bleaching protocols using violet LED.

PURPOSE: There has been growing demand for dental bleaching worldwide, however, despite being effective, hydrogen peroxide (HP) can negatively affect the dental structure. Thus, new techniques, such as violet LED light have emerged and need to be studied. The aim of this study was to analyze and compare the effectiveness of violet LED light alone or combined with 35% HP gel. METHODS: Six different tooth bleaching techniques (n = 10) were performed in intrinsically pigmented bovine teeth: G1 - 35% HP (1x/week for 4 weeks, 45 min of gel application); G2 - 35% HP (1x/week for 4 weeks, 15 min of gel application); G3 - violet LED (1x/week for 4 weeks); G4 - violet LED (2x/week for 2 weeks); G5 - violet LED (4x/week for 1 week); G6 - Violet LED + 35% HP (hybrid technique, 1x/week for 4 weeks, 15 min of gel application). Specimens were submitted to color evaluation at predetermined times using Konica Minolta® spectrophotometer, and the surface morphology (n = 3) was qualitatively analyzed by Scanning Electron Microscope (SEM). Data of the color change test were analyzed considering a 5% level of significance. RESULTS: There was significant difference in color (p <0.05) for all groups after bleaching protocols. SEM analysis revealed that the greatest change in surface occurred in Group G1, with demineralization of the dental enamel. When considering the same time interval, there were no statistical differences for axis L*, but differences were shown for axis a* (G2, G3, G4 ≥ G1, G5 ≥ G6) and b* (G1, G2, G3, G4, G5 > G6). Regarding the comparison of ΔE00 between groups, results showed statistical difference between groups, with G1 ≥ G2, G5, G6 ≥ G3, G4. CONCLUSION: Bleaching protocols with less time (15 min) or no exposure to 35% HP (violet LED, 4x/week) could promote bleaching results as those obtained by the conventional technique using 35% HP for 45 min, with no enamel surface changes, showing to be a promising alternative to tooth bleaching.

Influence of different intraradicular chemical pretreatments on the bond strength of adhesive interface between dentine and fiber post cements: A systematic review and network meta-analysis.

Systematic review and network meta-analyses were performed to answer the question: Do intraradicular chemical pretreatments affect the bond strength of the adhesive interface between dentine and fiber post cements? A literature search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, and Cochrane Library in October 2018 (updated September 2021). In vitro studies that compared the bond strength assessed by push-out tests following at least two dentine chemical treatments prior to fiber post cementation were included. Risk of bias was evaluated. A random-effects Bayesian-mixed treatment comparison model was used to compare push-out bond strength of different chemical pretreatments. SUCRA (surface area under the cumulative ranking) analysis was performed to rank the pretreatments. After removing duplicates and screening titles and abstracts, 61 studies remained. SUCRA analysis showed that the best bond strength values for self-etch, etch-and-rinse, and self-adhesive cements were ethyl acetate (SUCRA: 99.8%), low concentration NaOCl (SUCRA: 83.4%), and grape seed extract (SUCRA: 97.6%), respectively. According to the SUCRA rankings, ethanol was in a good position for all adhesive strategies (SUCRA: 78.6%). The use of chemical pretreatments in intraradicular dentine of endodontically treated teeth depends on the adhesive and cementation strategy. The pretreatment generally associated with the highest bond strength was ethanol.

Effect of intraradicular fiber post on the fracture resistance of endodontically treated and restored anterior teeth: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: A fiber post is indicated when there is a significant loss of tooth structure and additional support for the restoration is needed. However, whether the use of a glass fiber post affects the fracture susceptibility of the restored anterior teeth is unknown. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the fracture resistance of endodontically treated and restored anterior teeth and to answer the research question, "Does the use of a fiber post influence the fracture resistance of endodontically treated and restored anterior teeth compared with alternative restorative treatments?" MATERIAL AND METHODS: A search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, and Embase databases without date and/or language restrictions (updated in July, 2020). In vitro studies comparing the fracture strength of endodontically treated and restored anterior teeth with and without fiber posts were included. The risk of bias was evaluated by using the previous meta-analyses of in vitro studies. The results were presented as standardized mean difference with a 95% confidence interval. Statistical heterogeneity of treatment effects between studies was assessed using the Cochran Q test and the I2 inconsistency test, and values greater than 50% were considered indicative of substantial heterogeneity. RESULTS: After the removal of duplicates and title and abstract screening, 31 studies remained. Seventeen were considered low risk of bias, 10 were medium risk of bias, and 4 were high risk of bias. Meta-analysis comparing control and experimental groups favored the use of a fiber post in endodontically treated teeth with some types of restoration to improve fracture resistance (standardized mean difference= 0.5 [0.08; 0.92]); a glass fiber post was also favored (standardized mean difference=0.92 [0.43; 1.42]); for veneer preparations and teeth with cervical cavities, a fiber post increases the fracture strength (standardized mean difference= 0.74 [0.01; 1.47]; 1.18 [0.35; 2.02], respectively). CONCLUSIONS: The use of glass fiber posts increases the fracture resistance of endodontically treated and restored teeth.

Monowave and polywave light-curing of bulk-fill resin composites: degree of conversion and marginal adaptation following thermomechanical aging.

Aim: This study aimed to evaluate the effect of polymerization with either a monowave (MW) or a polywave (PW) light-curing unit (LCU) on the degree of conversion (DC) and marginal adaptation following thermomechanical aging of an ormocer bulk-fill resin composite (RC) (Admira fusion X-tra Bulk Fill - AB), a methacrylate-based bulk-fill RC (Tetric N-Ceram Bulk Fill - TB) and a conventional RC (Tetric N-Ceram - TC). Methods: DC was assessed in five samples of each RC using Fourier transform infrared spectroscopy. For determination of marginal adaptation, standard preparations were made in 60 bovine incisors, divided into three groups, according to the RC. The bulk-fill RC was inserted in a single increment of 4 mm. In contrast, the conventional RC was inserted in three increments. Marginal gap was evaluated after thermomechanical aging. Data were analyzed using a two-way analysis of variance (ANOVA) and Tukey's tests for multiple comparisons (α = 0.05). Results: The two-way ANOVA showed a significant effect (p<.05) of the RC factor but not of the LCU factor. The Tukey test showed that TB had the significantly lowest DC followed by TC, and with AB having the significantly highest DC. For the marginal adaptation, a significant effect was found for the LCU factor and the for the interaction RC × LCU (p<.05). Groups light-cured with PW showed significantly wider marginal gaps than MW. TC presented wider marginal gaps (17.36 µm) when cured with PW than when cured with MW (13.05 µm). The two bulk-fill RC resulted in similar marginal gap formation to each other. Conclusion: The ormocer-based bulk-fill RC showed a higher DC than the methacrylate-based bulk-fill RC but similar marginal adaptation. The LCU, MW or PW, had no significant influence on the DC, and no relevance on the marginal adaptation.

Protocols to control contamination and strategies to optimize the clinical practice in Restorative Dentistry during the COVID-19 pandemic / Protocolos para controle de contaminação e estratégias para otimizar a prática clínica em Odontologia Restauradora durante a pandemia de COVID-19

The current outbreak of coronavirus 2019 (COVID-19) challenges how professional standards have been defined so far. In Dentistry, biosafety measures already taken by professionals have been intensified, aiming to offer the patient urgent and emergency treatment with safety for both. In this context, Restorative Dentistry is responsible for the care of patients with caries injuries, with or without symptoms and, fractures of teeth and existing restorations. This article guides professionals, during the pandemic period, on the risks involved in adult and pediatric dental care for patients with restorative needs. It also discusses strategies to optimize clinical practice, reducing risks of contamination and virus transmission. (AU)

O atual surto de coronavírus 2019 (COVID-19), fez com que muitos profissionais repensassem sua postura de trabalho. Na Odontologia, medidas de biossegurança já realizadas pelos profissionais, foram intensificadas, com o objetivo de oferecer ao paciente um tratamento de urgência e emergência com segurança para ambos. Neste contexto, a Odontologia Restauradora é responsável pelo atendimento de pacientes com lesões de cárie, com ou sem sintomatologia, e fraturas de dentes e restaurações já existentes. Este trabalho orienta os profissionais quanto aos riscos envolvidos no atendimento odontológico, adulto e pediátrico, de paciente com necessidades restauradoras durante o período de pandemia. O artigo também discute estratégias para otimizar o atendimento, diminuindo riscos de contaminação e transmissão do vírus. (AU)

Effect of glass-fiber post on the biomechanical behavior of teeth with direct veneers / Efeito do pino de fibra de vidro no comportamento biomecânico de dentes com facetas diretas

Objective: This study aimed to evaluate the biomechanical behaviour of endodontically treated teeth with direct veneer that received or not intra-radicular glass fiber post by finite elements analysis. Material and methods: Six models were designed, varying the presence or absence of glass fiber post and the thickness of direct veneer (0.5, 0.7 and 1 mm). Tridimensional models of maxillary central incisors were obtained with CAD software, Rhinoceros 4.0, and transferred to CAE software, ANSYS 17.2, which a 100N load was applied in a 45° on the lingual surface to simulate functional movements. Geometry contacts were bonded, and the structures were isotropic, linear, elastics, and homogeneous. After coherence and convergence analysis of mashes, the chosen fail criterion was the maximum principal stresses. Results: For cement, glass fiber post, the stress distribution was similar independently of glass fiber post presence or veneer thickness. Models with glass fiber post had better stress distribution and lower values of maximum stress for inner dentin and veneers. Veneers with 0.5 and 1 mm had higher stress concentration areas. Conclusions: It can be concluded that glass fiber post is favorable for restored teeth with direct veneers, and very thin or very thick preparations can damage the biomechanical behavior of restorations.(AU)

Objetivo: Este estudo teve como objetivo avaliar o comportamento biomecânico de dentes tratados endodonticamente com faceta direta que receberam ou não pinos de fibra de vidro intrarradicular através de análise de elementos finitos. Material e métodos: Foram desenhados seis modelos, variando a presença ou ausência do pino de fibra de vidro e a espessura da faceta direta (0,5, 0,7 e 1 mm). Modelos tridimensionais de incisivos centrais superiores foram obtidos com o software CAD, Rhinoceros 4.0, e transferidos para o software CAE, ANSYS 17.2, cuja carga de 100N foi aplicada a 45° na superfície lingual para simular movimentos funcionais. Os contatos geométricos foram colados e as estruturas eram isotrópicas, lineares, elásticas e homogêneas. Após análise de coerência e convergência de malhas, o critério de falha escolhido foi a tensão principal máxima. Resultados: Para cimento e pino de fibra de vidro, a distribuição de tensões foi semelhante independentemente da presença do pino de fibra de vidro ou da espessura da faceta. Os modelos com pinos de fibra de vidro apresentaram melhor distribuição de tensão e menores valores de tensão máxima para dentina interna e facetas. Facetas com 0,5 e 1mm apresentaram maiores áreas de concentração de estresse. Conclusões: Pode-se concluir que o pino de fibra de vidro é favorável para dentes restaurados com facetas diretas, e preparações muito finas ou muito espessas podem prejudicar o comportamento biomecânico das restaurações.(AU)

O uso de pino de fibra em dentes tratados endodonticamente / Glass fiber post use in endodontically treated teeth

Este estudo envolve um estudo in sílico, um ensaio clínico randomizado e duas revisões sistemáticas com o objetivo de compreender a influência dos pinos de fibra (PF) na resistência à fratura de dentes tratados endodonticamente e restaurados e também, avaliar o efeito de tratamentos químicos dentinários na resistência de união da cimentação do PF na dentina intrarradicular. Estudo in silico: seis modelos tridimensionais de incisivos centrais superiores foram projetados em um software de desenho e se diferenciaram de acordo com a presença ou ausência de PF de vidro e espessura das facetas diretas de resina composta (0,5, 0,7 e 1 mm). Foram transferidos para o software ANSYS 17.2, no qual movimentos funcionais foram simulados com carga de 100 N a 45º nas faces linguais. Os modelos com PF apresentaram melhor distribuição de tensões e menores valores de tensão máxima na região da dentina e faceta. Ensaio clínico randomizado: selecionou-se 50 pacientes com necessidade de faceta em um incisivo central ou lateral superior tratado endodonticamente. Foram divididos em dois grupos (n=25) de acordo com o uso ou não de PF de vidro. Após 6 e 12 meses do tratamento, avaliações clínicas e radiográficas em relação à presença e tipo de fratura, apontaram taxas de sucesso de 96% para o grupo sem PF e 100% para o grupo com PF, sem diferenças estatisticamente significativas. Revisão sistemática e metanálise: as bases de dados PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library e Embase foram acessadas com a estratégia de busca definida de acordo com a pergunta: ' O uso de PF influencia na resistência à fratura de dentes anteriores tratados endodonticamente e restaurados, quando comparados com o não uso de PF? ' Foram incluídos 32 estudos in vitro. Após a metanálise, pode-se concluir que o uso de PF favoreceu a resistência à fratura dos dentes, principalmente para dentes com preparo para faceta e cavidades cervicais e os PF de vidro mostraram resultados mais satisfatórios. Revisão sistemática e metanálise em rede: as bases PubMed, Scopus, Web of Science, LILACS, BBO e Cochrane Library foram acessadas com a estratégia de busca definida de acordo com a pergunta: ' Tratamentos químicos da dentina intrarradicular afetam a força de união de PF em dentes tratados endodonticamente? ' Foram incluídos 61 estudos in vitro. Foi realizada a avaliação do risco de viés para estudos in vitro. Após a metanálise em rede e análise de SUCRA para cada estratégia de cimentação (adesivo autocondicionante, adesivo de condicionamento total e cimento autoadesivo), concluiu-se que os tratamentos químicos da dentina intrarradicular que melhoram a força de união da cimentação de PF são o acetato de etila para adesivos autocondicionantes, NaOCl em baixa concentração para adesivos de condicionamento total e extrato de semente de uva para cimentos autoadesivos(AU)

This study involves an in silico study, a randomized clinical trial, and two systematic reviews to understand the influence of fiber posts (FP) on fracture strength of endodontically treated and restored teeth and also to evaluate the effect of dentin chemical treatments on bond strength of FP cementation in intraradicular dentin. In silico study: six three-dimensional models of maxillary central incisors were designed in a CAD software and differed according to the presence or absence of glass FP and thickness of composite resin direct veneer (0.5, 0.7 and 1 mm). They were transferred to the ANSYS 17.2 software, in which functional movements were simulated with a load of 100N at 45º on the lingual surfaces. The models with glass FP showed better stress distribution and lower maximum stress values in the dentin and veneer region. Randomized clinical trial: 50 patients who needed veneer treatment of an endodontically treated central or lateral maxillary incisor were selected. They were divided into two groups (n=25) according to the use or not of glass FP. Direct composite resin veneers were performed for two groups. In the FP group, they were cemented with self-adhesive resin cement. Descriptive data of the population and restored teeth were collected. After 6 and 12 months of treatment, clinical and radiographic evaluations regarding the presence and type of fracture indicated success rates of 96% for the group without FP and 100% for the group with FP, with no statistically significant differences. Systematic review and meta-analysis: PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library and Embase databases were accessed with the search strategy defined according to the question: "Does the use of FP influence on fracture strength of endodontically treated and restored anterior teeth when compared to non-use of fiber posts?" Thirty-two in vitro studies were included. Bias risk assessment was based on existing systematic reviews of in vitro studies. After the meta-analysis, it can be concluded that the use of FP favored the fracture resistance of teeth, especially for teeth with veneer preparation and cervical cavities and the glass FP showed more satisfactory results. Systematic review and network meta-analysis: PubMed, Scopus, Web of Science, LILACS, BBO and Cochrane Library databases were accessed with the search strategy defined according to the question: 'Do intraradicular dentin chemical pretreatments affect the bond strength of fiber posts for endodontically treated teeth?' Sixty-one in vitro studies were included. Bias risk assessment for in vitro studies was performed. After network meta-analysis and SUCRA analysis for each cementation strategy (self-etching adhesive, total etching adhesive and self-adhesive cement), it was concluded that the intraradicular dentin chemical treatments that improve the bond strength of FP cementation are ethyl acetate for self-etching adhesive, low concentration NaOCl for total etching adhesives and grape seed extract for selfadhesive cements(AU)

Six-month performance of restorations produced with the ethanol-wet-bonding technique: a randomized trial.

This double-blind randomized controlled clinical trial evaluated the effectiveness of dentin pretreatment with 100% ethanol (EWBT - ethanol wet bonding technique) and different adhesive protocols in noncarious cervical lesions (NCCL) after 6 months. Patients presenting at least one NCCL were included. NCCLs (n=148) were randomly assigned to 4 groups: NE (Non-EWBT + three-step etch-and-rinse (Scotchbond Multi Purpose, 3M ESPE [MP]), E (EWBT + MP); EB (EWBT + [Bond - third step of MP]), and EU (EWBT + universal adhesive (Single Bond Universal, 3M ESPE). Conventional acid-etching (Condac 37%, FGM) and nanohybrid resin composite (Z350, 3M ESPE) were used. Trained and calibrated examiners (Kappa = 0.61) evaluated the restorations at baseline (7 days) and 6-month recall using the USPHS modified criteria. Data were subjected to Chi square (α = 0.05). Differences in the success rate were found for the treatments (p = 0.003). EB presented the lowest success rate compared with the other groups (p < 0.02). No significant differences were detected among NE, E, and EU (p > 0.49). The survival rates were 97.23%, 97.30%, 78.95%, and 97.30% for NE, E, EB, and EU, respectively. Regarding postoperative sensitivity, a significant reduction was found for groups E (p = 0.027) and EU (p < 0.01) after 6 months. After 6 months, EWBT associated to the hydrophobic adhesive system had the highest failure rate.

Six-month performance of restorations produced with the ethanol-wet-bonding technique: a randomized trial

Abstract This double-blind randomized controlled clinical trial evaluated the effectiveness of dentin pretreatment with 100% ethanol (EWBT - ethanol wet bonding technique) and different adhesive protocols in noncarious cervical lesions (NCCL) after 6 months. Patients presenting at least one NCCL were included. NCCLs (n=148) were randomly assigned to 4 groups: NE (Non-EWBT + three-step etch-and-rinse (Scotchbond Multi Purpose, 3M ESPE [MP]), E (EWBT + MP); EB (EWBT + [Bond - third step of MP]), and EU (EWBT + universal adhesive (Single Bond Universal, 3M ESPE). Conventional acid-etching (Condac 37%, FGM) and nanohybrid resin composite (Z350, 3M ESPE) were used. Trained and calibrated examiners (Kappa = 0.61) evaluated the restorations at baseline (7 days) and 6-month recall using the USPHS modified criteria. Data were subjected to Chi square (α = 0.05). Differences in the success rate were found for the treatments (p = 0.003). EB presented the lowest success rate compared with the other groups (p < 0.02). No significant differences were detected among NE, E, and EU (p > 0.49). The survival rates were 97.23%, 97.30%, 78.95%, and 97.30% for NE, E, EB, and EU, respectively. Regarding postoperative sensitivity, a significant reduction was found for groups E (p = 0.027) and EU (p < 0.01) after 6 months. After 6 months, EWBT associated to the hydrophobic adhesive system had the highest failure rate.

Effect of pH on whitening efficacy of 35% hydrogen peroxide and enamel microhardness.

OBJECTIVE: This study aimed to evaluate the effect of 35% hydrogen peroxide at different pH values and the degree of tooth staining on whitening efficacy and enamel microhardness. MATERIALS AND METHODS: 90 enamel-dentin specimens were obtained from bovine incisors. They were randomly divided into 2 groups (n = 45), 1 group was immersed in a staining broth for 14 days, and another group was not stained and kept in distilled water at 37°C. Twenty-four hours after the staining procedure, each group was distributed into 3 subgroups that were whitened by 35% hydrogen peroxide with different pH values (5, 7, and 8.4) for 30 minutes. The color was measured at baseline and 7 days after whitening. Microhardness was measured at baseline, immediate, 24 hours, and 1 month after the whitening procedure. Data were submitted to 2-way analysis of variance (ANOVA) and the Tukey test for multiple comparisons for color analysis. Repeated measures ANOVA and the Tukey test were used to analyze microhardness data. RESULTS: The color change of the stained groups (ΔE00 = 4.6) was significantly higher than that of the nonstained groups (ΔE00 = 3.7). Microhardness value decreased significantly immediately after whitening for all subgroups and did not return to initial values. For each measurement time, microhardness was not significantly different among subgroups with different pH values. CONCLUSIONS: Despite the effectiveness of 35% hydrogen peroxide, changes on gel pH did not affect the whitening efficacy, and the enamel was superficially demineralized, regardless of pH values. CLINICAL SIGNIFICANCE: Independently of the pH value of whitening gel, enamel undergoes superficial demineralization and with a reduction in superficial microhardness that does not return to the initial values. However, using hydrogen peroxide with different pH values does not alter the whitening effect.

Eficácia de agentes clareadores de venda livre associados ou não ao clareamento com Peróxido de Carbamida a 10 por cento / Efficacy of over-the-counter whitening products associated with 10 % carbamide peroxide home-bleaching

O objetivo deste estudo foi avaliar a cor, fluorescência, e microdureza de agentes clareadores de venda livre associados ou não ao clareamento com Peróxido de Carbamida a 10% (PC10%) e comparar sua eficácia ao do clareamento caseiro com gel de PC10%. Duzentos e dez espécimes de esmalte e dentina foram obtidos a partir de incisivos bovinos e manchados em caldo de manchamento durante 14 dias. Foram randomizados em dois grupos, um deles foi clareado previamente com Peróxido de Carbamida a 10% (PC) e o outro não. Cada grupo foi subdividido em 7 subgrupos de acordo com o produto (n = 15): PC-Lis e Lis­ enxaguatório clareador (Listerine Whitening); PC-AG e AG ­ água deionizada; PC-E e E­ escovação mecânica. PC-EConv e EConv ­ creme dental convencional (Colgate Total Clean Mint); PC-EPerox e EPerox (Colgate Luminous White Advanced); PC-EAbras e EAbras (Oral-B 3D White Luxe); e PC-EOpt e EOpt (Close Up Diamond Attraction) ­ dentifrícios clareadores. O grupo clareado com PC10% foi submetido a 14 dias de ciclos diários de clareamento caseiro associado aos tratamentos com agentes de venda livre. Após isso, todos os subgrupos passaram por ciclos de escovação ou enxágue durante 12 semanas. As medidas de cor, fluorescência e microdureza foram realizadas após o manchamento, após o clareamento com PC10% e após as 12 semanas dos tratamentos com os agentes clareadores de venda livre. Os dados de cor foram analisados pelo teste de análise de variância (ANOVA) e teste de Tukey de comparações múltiplas. Para fluorescência e microdureza foi utilizado o teste Tukey no grupo clareado com PC10%, e teste t-pareado para o outro grupo. Na comparação dos produtos com o PC10%, foi utilizado o teste de Dunnet. Para o grupo clareado com PC10% os resultados foram: valores do ∆Eab* e ∆b* foram semelhantes após o clareamento com PC10%, após 12 semanas PC-Lis e PC-AG apresentaram os menores valores de ∆Eab* e PC-Lis, PC-AG e PC-E apresentaram maiores valores de ∆b; A fluorescência aumentou para todos os grupos e após 12 semanas, diminuiu significativamente para PC-AG e PC-E. Para a dureza não houve diferenças estatísticas entre os subgrupos. Para o grupo não clareado com PC10%: Lis, EConv, EPerox, EOpt, e EAbras apresentaram valores negativos para ∆b, mostrando eficácia clareadora significantemente maior que AG e E; após 12 semanas a microdureza do subgrupo EConv aumentou; a fluorescência aumentou para Lis, EConv, EPerox, EAbras e EOpt. Nenhum dos agentes clareadores de venda livre apresentou valores semelhantes ao clareamento com PC10%. Pode-se concluir que todos dentifrícios testados são capazes de manter o clareamento obtido pelo PC10%, já o enxaguatório não teve a mesma eficácia. Quando não associados ao clareamento com PC10% os agentes clareadores de venda livre promovem efeito clareador similar, mas não promovem o mesmo efeito do PC10%. (AU)

The aim of this study was to evaluate color change, fluorescence and microhardness of different over-the-counter (OTC) whitening products, and to compare them with 10% carbamide peroxide (10%CP) gel. Two hundreds and ten enamel-dentin specimens were obtained from bovine incisors and stained in staining broth for 14 days, then randomly divided into 2 groups, one of them was bleached with 10%CP and the other was not bleached. Each group was divided into 7 subgroups according to type of product (n = 15): PC-Lis and Lis­ whitening mouth rinse (Listerine Whitening); PC-AG and AG ­ deionized water; PC-E and E­ mechanical brushing. PC-EConv and EConv ­ conventional dentifrice (Colgate Total Clean Mint); PCEPerox and EPerox (Colgate Luminous White Advanced); PC-EAbras and Eabras (Oral-B 3D White Luxe); and PC-EOpt and EOpt (Close Up Diamond Attraction) ­ whitening dentifrices. Bleached groups were submitted to daily cycles of at-home bleaching associated with OTC whitening products. Then, all subgroups were submitted to cycles of whitening of OTC whitening products. Color, fluorescence and microhardness were measured after staining and after bleaching with 10%CP and after 12 weeks of whitening treatment with OTC products. Color data was submitted for analysis of variance and Tukey's test for multiple comparisons, for microhardness and fluorescence, Tukey's test was used for bleached groups and paired t-test was used for non-bleached group. In comparison of OTC whitening agents with 10%CP bleaching was used Dunnet's test. Results for bleached group: ∆Eab* and ∆b* values was similar after 10%CP bleaching; after 12 weeks PC-Lis e PC-AG presented lower values of ∆Eab* and PC-Lis, PC-AG and PC-E presented lower values of ∆b*; fluorescence increased for all groups after 10%CP treatment and after 12 weeks, decreased significantly for PC-AG and PC-E. For microhardness there were not statistical differences between subgroups. For non-bleached group: Lis, EConv, EPerox, EOpt, and EAbras presented negative ∆b* values, showing bleaching efficacy significantly higher than AG and E. After 12 weeks EConv microhardness values was increased and fluorescence was increased for Lis, EConv, EPerox, EAbras and EOpt. None of the OTC agents presented a whitening effect similar to 10%CP. It is concluded that all dentifrices tested were able to preserve bleaching obtained with 10%CP, the mouth rinse did not present the same efficacy. When they were not associated with 10%CP, they promoted a similar whitening effect. Despite this, OTC whitening agents did not present a similar whitening effect compared to athome bleaching with 10%CP.(AU)