Influence of dental erosion on shear bond strength of ceramic brackets bonded with two different adhesive systems: an in vitro study

This study aimed to analyze the shear bond strength (SBS) of ceramic orthodontic brackets bonded with two different adhesive systems to intact and eroded teeth. Ceramic brackets were bonded to 72 bovine central incisors divided into four groups, defined by two study factors: enamel condition (control group, kept in artificial saliva; and experimental group, eroded by using immersion cycles in Coke™ for 90 seconds, every six hours for five days), and adhesive system type (Transbond™ XT or Transbond™ Plus Color Change). Polycrystalline ceramic brackets were adhesively fixed on all specimens using the same light curing protocol. SBS was tested using 0.5 mm/min and the failure mode was classified. SBS data was analyzed using two-way ANOVA followed by Tukey test. The adhesive remnant index (ARI) scores were analyzed using Kruskal-Wallis test with Dunn's post-hoc pairwise comparison (α=0.05). Percentages of ARI scores between the groups were compared by Fisher's exact test. Spearman's correlation coefficient was applied to investigate the correlation between ARI scores and SBS values. Only the adhesive system factor had significant effect on SBS (p=0.014), Transbond™ Plus Color Change showing higher values. No significance was found for enamel condition (p=0.665) or the interaction between adhesive system and enamel condition (p=0.055). ARI scores frequencies differed between groups (p<0.001). The median ARI scores were statistically different for most comparisons among the groups. However, no significant correlation was found between ARI scores and SBS. In conclusion, the type of adhesive system affected the SBS of ceramic brackets to dental enamel, but the enamel condition, intact or eroded, had no significant effect. There was no correlation between ARI scores and SBS values, although eroded enamel tended to retain more adhesive after bracket removal.

Influence of surface sealant and erosive challenge on the color change of composite resin subjected to artificial staining.

The aim of this study was to evaluate the influence of surface sealant and erosive challenge on the color change of composite resin after artificial staining with coffee. Forty-eight composite specimens (8 × 1 mm) were prepared and divided into 4 groups (n = 12) based on the timing of sealant application (immediate vs delayed) and exposure to acid (erosive challenge vs no challenge). The groups were subjected to the procedures in the following order: 1, sealant application, erosive challenge, color measurement, coffee immersion, and color measurement; 2, sealant application, color measurement, coffee immersion, and color measurement; 3, erosive challenge, color measurement, sealant application, coffee immersion, and color measurement; and 4, color measurement, sealant application, coffee immersion, and color measurement. In groups 1 and 2, surface sealant was applied immediately after preparation of the specimens. In groups 3 and 4, sealant was applied after the first color measurement. Color was measured with a spectrophotometer using the CIE L*a*b* system. The erosive challenge (groups 1 and 3) was carried out in 0.01M hydrochloric acid, 150 mL/cycle, at room temperature (2-minute immersions 4 times a day for 5 days). After all specimens were immersed in coffee for 14 days, new color measurements were performed. For total color change (∆E*), groups 1 (21.01) and 2 (23.10) presented lower values than groups 3 (27.76) and 4 (26.57). For luminosity (∆L*), the opposite occurred (groups: 1, -16.84; 2, -17.72; 3, -22.62; and 4, -21.22). For ∆a* and ∆b*, the only statistically significant difference was the group 1 ∆b* value, which was the lowest among all groups. The opacity remained stable in all groups. The results suggest that resin luminosity decreases and color variation increases when surface sealant is applied after erosive cycling and storage.

Functional and aesthetic rehabilitation in posterior tooth with bulk-fill resin composite and occlusal matrix.

The restorative procedure in posterior teeth involves clinical steps related to professional skill, especially when using the incremental technique, which may fail in the long term. A recent alternative is bulk-fill resins, which can reduce polymerization shrinkage, decreasing clinical problems such as marginal leakage, secondary caries, and fracture. This scientific study aims to report a clinical case using bulk-fill resin with an occlusal matrix. As determined in the treatment plan, an acrylic resin matrix was produced to establish an improved oral and aesthetic rehabilitation of the right mandibular first molar, which presented a carious lesion with dentin involvement. The occlusal matrix is a simple technique that maintains the original dental anatomy, showing satisfactory results regarding function and aesthetic rehabilitation.

Dental Bleaching, Microabrasion, and Resin Infiltration: Case Report of Minimally Invasive Treatment of Enamel Hypoplasia.

Enamel hypoplasia occurs because of a defect in formation of the organic matrix during the development of tooth enamel. Minimally invasive procedures of the slightly altered enamel contribute to a greater longevity of teeth and prevent them from relapsing into the repetitive restorative cycle. This case history report aimed to show a sequential technique of minimally invasive procedures for esthetic resolution in anterior teeth. Prior to microabrasion, anterior teeth were bleached in office with 37% hydrogen peroxide. Afterwards, hypoplastic spots on the buccal incisal thirds of the maxillary central incisors were treated with two sessions of microabrasion using phosphoric acid and pumice stone and one session using resin infiltrant. Besides a slight remaining white spot on tooth 21, the masking of spots was done with this sequence of treatments, re-establishing color harmony. Spot depth, diagnosis, and the most relevant treatment choice determined the clinical success.

Top-100 Most Cited Dental Articles with Authors from Brazil.

This study analyzes the characteristics of the top-100 most cited articles published in international dental journals with at least one coauthor affiliated to Brazil. A search in Scopus database for articles published between 1996 and 2017 was carried out in the 178 journals belonging to the category "Dentistry" identified in SCImago Journals & Country Rank. From the top-100 most cited articles, variables related to the journal, article, and authors were collected. Annual citation averages (ACA) and relative citation ratios (RCR) were calculated. Data were analyzed descriptively. There were 75 original reports and 25 reviews in the sample. The number of citations ranged between 124 and 657 (mean=202, median=168). The papers were published in 31 different journals (46% in only four journals), none based in Brazil. The most frequent subjects (61%) were Dental Materials, Endodontics, and Periodontology, which accounted for 63.6% of the total citations. The subject with the highest ACA was Oral and Maxillofacial Surgery and the subject with the highest RCR was Oral Radiology. Only 12 articles were cited more than 300 times. International collaboration was present in 61 articles and funding was reported in 49 articles. The first author was from Brazil in 70% and corresponding author in 55% of the papers. Southeast (83%) and South (20%) were the regions of Brazil with most presence of coauthors. This top-100 list is presented to provide an overview of the most cited articles and aid in supporting further analyses regarding publication and citation behaviors of Brazilian dentistry.

Top-100 most cited dental articles with authors from Brazil

Abstract This study analyzes the characteristics of the top-100 most cited articles published in international dental journals with at least one coauthor affiliated to Brazil. A search in Scopus database for articles published between 1996 and 2017 was carried out in the 178 journals belonging to the category "Dentistry" identified in SCImago Journals & Country Rank. From the top-100 most cited articles, variables related to the journal, article, and authors were collected. Annual citation averages (ACA) and relative citation ratios (RCR) were calculated. Data were analyzed descriptively. There were 75 original reports and 25 reviews in the sample. The number of citations ranged between 124 and 657 (mean=202, median=168). The papers were published in 31 different journals (46% in only four journals), none based in Brazil. The most frequent subjects (61%) were Dental Materials, Endodontics, and Periodontology, which accounted for 63.6% of the total citations. The subject with the highest ACA was Oral and Maxillofacial Surgery and the subject with the highest RCR was Oral Radiology. Only 12 articles were cited more than 300 times. International collaboration was present in 61 articles and funding was reported in 49 articles. The first author was from Brazil in 70% and corresponding author in 55% of the papers. Southeast (83%) and South (20%) were the regions of Brazil with most presence of coauthors. This top-100 list is presented to provide an overview of the most cited articles and aid in supporting further analyses regarding publication and citation behaviors of Brazilian dentistry.

Resumo Este artigo analisa as características dos 100 artigos mais citados publicados em periódicos internacionais de odontologia com ao menos um co-autor afiliado ao Brasil. Uma busca na base de dados Scopus por artigos publicados entre 1996 e 2017 foi realizada nos 178 periódicos pertencentes à categoria "Dentistry" identificados no SCImago Journals & Country Rank. Dos 100 artigos mais citados, variáveis relacionadas ao periódico, artigo e autores foram coletadas. Médias anuais de citação (MAA) e razões de citação relativa (RCR) foram calculadas. Os dados foram analisados descritivamente. A amostra foi composta por 75 artigos originais e 25 revisões. O número de citações variou entre 124 e 657 (média=202, mediana=168). Os artigos foram publicados em 31 periódicos diferentes (46% em apenas quatro periódicos), nenhum do Brasil. Os temas mais frequentes (61%) foram Materiais Dentários, Endodontia e Periodontia, somando 63,6% do total de citações. O tema com maior MAA foi Cirurgia Oral e Maxilofacial e o tema com maior RCR foi Radiologia Oral. Apenas 12 artigos foram citados mais de 300 vezes. Colaboração internacional estava presente em 61 artigos e financiamento foi reportado em 49 artigos. O primeiro autor era do Brasil em 70% e o correspondente em 55% dos artigos. As regiões do Brasil com mais co-autores presentes foram Sudeste (83%) e Sul (20%). Esta lista é apresentada para prover uma fotografia dos 100 artigos mais citados e ajudar a fomentar análises posteriores em relação a comportamentos de citação e publicação da odontologia brasileira.

Composite vs. ionomer vs. mixed restoration of wedge-shaped dental cervical lesions: Marginal quality relative to eccentric occlusal loading.

Dental cervical restorations may be impacted by resultants of occlusal loads that may have already contributed to the development of the lesion and should rely on materials' favorable properties to bear the stresses. The marginal quality of cervical restorations made with materials of different moduli of elasticity in essence, isolated, or in combination, was evaluated relative to eccentric occlusal loading. Cervical wedge-shaped cavities, prepared in extracted premolars, were restored with a composite resin (CR), a restorative ionomer (GIC), or the composite in combination with a lining ionomer (Mixed restoration: M). Half of the teeth in each group were subjected to eccentric occlusal loading (eol; 150 N / 106 cycles / 2.5 Hz; CReol / GICeol / Meol, n = 10), and the others were stored in 37 °C distilled water (Control: c; CRc / GICc / Mc, n = 10). A fluorescein-modified adhesive favored delimitation of formed gaps, which were evaluated by confocal laser scanning microscopy regarding their presence, location related to the cavity walls, and width and depth (µm), at a 5% significance level. From a comprehensive perspective, neither the loading nor the materials were significantly associated with the qualitative response variables or exerted any influence over the quantitative variables. More specifically, the use of the different materials was significantly associated with the frequency of gaps exclusively when loading was applied (Chi-square test, p = 0.029, CR > M > GIC). Though the marginal quality of cervical restorations may not be influenced by eccentric occlusal loading or the use of different materials, even in association in general, the unfavorable aspects of the use of the composite may be relevant, particularly in face of the existence of eccentric occlusal loads.

Bond strength to ZLS ceramics at different etching times and cementation protocols after aging / Influência da cimentação e da termociclagem na resistência de união da cerâmica de silicato de lítio reforçada com zircônia

Objective: To assess the influence of 5% hydrofluoric acid etching time (ET), cementation protocol (CP), and thermal cycling (TC) aging on the microshear bond strength (µSBS) of zirconia reinforced lithium silicate ceramic (ZLS) to adhesive resin cement. Material and Methods: Ten VITA Suprinity® ceramic blocks were cut in 120 slices (1.4 mm thickness) and randomly assigned to 12 groups (n = 10) according to the combination of factors (2x3x2 design): etching time (20 or 30 s), cementation protocol (silane + universal adhesive + resin cement; universal adhesive + resin cement; silane + resin cement) and thermal cycling (cycled or no-cycled). RelyX Ceramic Primer and Scotchbond™ Universal Adhesive were used respectively as silane (S) and universal adhesive (Ua). Ceramic surface was etched, and the cementation protocol performed on the delimited bonding area. Then, resin cement (RelyX™ Ultimate Cement [Rc]) cylinders were bonded and light cured. After, specimens were stored in deionized water at 37°C for 7 days and subjected to the µSBS test. Results: Data passed the normality test and three-way ANOVA analysis showed statistical difference (p < 0.01) for isolated; double (ET/TC) (p < 0.05), and triple (p < 0.05) factor interactions. Conclusion: The combination 30s etching-Ua-Rc presented higher adhesive bond strength after thermal aging. (AU)

Objetivo: Avaliar a influência do tempo de condicionamento com ácido fluorídrico 5% (ET), protocolo de cimentação (CP), e envelhecimento por termociclagem (TC) na resistência de união ao microcisalhamento (µSBS) da cerâmica de silicato de lítio reforçada com zircônia (ZLS) ao cimento resinoso adesivo. Material e Método: Dez blocos da cerâmica VITA Suprinity® foram cortados e 120 fatias (com espessura de 1,4 mm) e distribuídos aleatoriamente em 12 grupos (n=10) de acordo com o fator de combinação (2x3x2): tempo de condicionamento (20 ou 30 s), protocolo de cimentação (silano + adesivo universal + cimento resinoso; adesivo universal + cimento resinoso; silano + cimento resinoso) e ciclagem térmica (ciclado ou não ciclado). RelyX Ceramic Primer e adesivo Scotchbond™ Universal foram utilizados respectivamente como silano (S) e adesivo universal (Ua). A superfície cerâmica foi condicionada e o protocolo de cimentação aplicado sobre área de cimentação delimitada. Portanto, cilindros de cimento resinoso (cimento RelyX™ Ultimate [Rc]) foram cimentados e fotopolimerizados. Após, os espécimes foram armazenados em água deionizada a 37°C por 7 dias e submetidos ao teste de µSBS. Resultados: Após teste de normalidade, os dados foram analisados pelo teste ANOVA três critérios mostrando diferença estatística (p < 0.01) para a análise do fator isolado; para a interação entre dois fatores (ET/TC) (p < 0.05), e interação entre os três fatores (p < 0.05). Conclusão: A combinação 30s de condicionamento-Ua-Rc apresentou a maior resistência de união adesiva após a ciclagem térmica.(AU)

Effect of two erosive protocols using acidic beverages on the shear bond strength of orthodontic brackets to bovine enamel

Abstract Objective: To assess the short-term effect of two in vitro erosive challenge protocols on the bond strength of metal orthodontic brackets on bovine enamel. Methods: Sixty bovine incisors were selected and randomly divided into six groups: AS7 (artificial saliva - 7 days, Control Group); CC7 (Coca-Cola™ - 7 days); LJ7 (lime juice - 7 days); AS30 (artificial saliva - 30 days, Control Group); CC30 (Coca-Cola™ - 30 days); LJ30 (lime juice - 30 days). Microhardness testing was performed prior to the erosive challenge to verify the standardization of samples. Immersion was performed 4x/day for five minutes, for either 7 or 30 days. After immersions were concluded, the brackets were bonded and shear bond strength was assessed after 48 hours. The Adhesive Remnant Index (ARI) was also assessed. Data were analyzed by two-way ANOVA, followed by Tukey's post-hoc and Student's t test for paired samples, and the Kruskal-Wallis non-parametric test (α = 5%). Results: The mean and standard deviation of microhardness testing of total samples were 281.89 ± 44.51 KHN. There was no statistically significant difference in shear bond strength for the time factor (7 or 30 days; F5.54= 0.105; p = 0.901). However, there was a statistically significant difference for the solution factor (F5.54= 6.671; p = 0.003). These differences occurred among solutions of Saliva x Coca-Cola™ (p = 0.003) and Coca-Cola™ x Lime Juice (p= 0.029). The assessment of the Adhesive Remnant Index showed no significant difference between groups. Conclusions: The immersion time used in the erosion protocols did not affect the bond strength of brackets to teeth. Coca-Cola™ induced significantly higher shear bond strength values than lime juice and artificial saliva. However, the short term effects of 7/30 days in this in vitro study may not be extrapolated for in vivo ones. Clinical studies should be conducted, substantiating the laboratory results.

Resumo Objetivo: avaliar o efeito de curto prazo de dois protocolos de desafio erosivo, in vitro, na resistência adesiva de braquetes ortodônticos metálicos em esmalte bovino. Métodos: Sessenta incisivos bovinos foram selecionados e divididos aleatoriamente em seis grupos: SA7 (saliva artificial - 7 dias, Grupo Controle); CC7 (Coca-Cola® - 7 dias); SL7 (suco de limão - 7 dias); SA30 (saliva artificial - 30 dias, Grupo Controle); CC30 (Coca-Cola® - 30 dias); SL30 (suco de limão - 30 dias). Foi realizado o teste de microdureza antes do desafio erosivo, para verificar a padronização das amostras. A imersão foi realizada quatro vezes ao dia, por cinco minutos, durante 7 ou 30 dias. Finalizadas as imersões, os braquetes foram colados e, após 48 horas, foi avaliada a resistência ao cisalhamento. O Índice de Adesivo Remanescente (IAR) também foi avaliado. Para análise dos dados, foram utilizados os testes ANOVA dois fatores, seguido do post-hoc de Tukey e teste t de Student para amostras pareadas, e o teste não-paramétrico de Kruskal-Wallis (α?#8197;= 5%). Resultados: a média e o desvio-padrão do teste de microdureza das amostras totais foi igual a 281,89 ± 44,51 KHN. Não houve diferença estatisticamente significativa na resistência ao cisalhamento para o fator tempo (7 ou 30 dias; F5,54= 0,105; p= 0,901). Contudo, houve diferença estatisticamente significativa para o fator solução (F5,54=6,671; p= 0,003). Essas diferenças ocorreram entre as soluções de Saliva x Coca-Cola® (p= 0,003) e Coca-Cola® x suco de limão (p= 0,029). Ao avaliar o Índice de Adesivo Remanescente, não foi possível verificar diferença significativa entre os grupos. Conclusões: o tempo de imersão utilizado nos protocolos de erosão não afetou a resistência de união dos braquetes aos dentes. A Coca-Cola® induziu valores de resistência ao cisalhamento significativamente mais altos do que o suco de limão e a saliva artificial. No entanto, os efeitos em curto prazo de 7 e 30 dias, nesse estudo in vitro, não podem ser extrapolados para os estudos in vivo. Estudos clínicos devem ser conduzidos, fundamentando os resultados laboratoriais.

Effectiveness of whitening mouthwashes on tooth color: an in vitro study.

Products for tooth whitening (or tooth color maintenance) that improve smile esthetics have become increasingly popular due to their easy accessibility and low cost. This in vitro study assessed the effect of whitening mouthwash on bovine tooth color. Forty-eight bovine teeth were divided into 3 immersion groups: SL, artificial saliva (control); CLW, Colgate Luminous White; and OBW, Oral-B 3D White. After prophylaxis with pumice, the initial color was measured using the CIE L*a*b* system. Teeth were immersed in the solutions for 2 minutes, 3 times per day, for 30 days. Changes in color (ΔE*, ΔL*, Δa*, and Δb*) were measured at days 14 and 30. Data were analyzed with 2-way analysis of variance and Tukey test (P < 0.05). At day 30, values of ΔE* had significantly decreased in group SL and increased in group OBW; in addition, at day 30, the ΔE*values in group CLW were significantly greater than those in group SL. The ΔL* values for groups SL and OBW significantly decreased from day 14 to day 30. At day 30, the Δa* and Δb* values were lower in all 3 groups. The results showed that the whitening mouthwashes did not improve color after 14 and 30 days.

Preemptive use of etodolac on tooth sensitivity after in-office bleaching: a randomized clinical trial.

This study determined the effectiveness of the preemptive administration of etodolac on risk and intensity of tooth sensitivity and the bleaching effect caused by in-office bleaching using 35% hydrogen peroxide. Fifty patients were selected for this tripleblind, randomized, crossover, and placebo-controlled clinical trial. Etodolac (400 mg) or placebo was administrated in a single-dose 1 hour prior to the bleaching procedure. The whitening treatment with 35% hydrogen peroxide was carried out in two sessions with a 7-day interval. Tooth sensitivity was assessed before, during, and 24 hours after the procedure using the analog visual scale and the verbal rating scale. Color alteration was assessed by a bleach guide scale, 7 days after each session. Relative risk of sensitivity was calculated and adjusted by session, while overall risk was compared by the McNemar's test. Data on the sensitivity level of both scales and color shade were subjected to Friedman, Wilcoxon, and Mann-Whitney tests, respectively (α=0.05). The preemptive administration of etodolac did not affect the risk of tooth sensitivity and the level of sensitivity reported, regardless of the time of evaluation and scale used. The sequence of treatment allocation did not affect bleaching effectiveness, while the second session resulted in additional color modification. The preemptive administration of etodolac in a single dose 1 hour prior to in-office tooth bleaching did not alter tooth color, and the risk and intensity of tooth sensitivity reported by patients. A single-dose preemptive administration of 400 mg of etodolac did not affect either risk of tooth sensitivity or level of sensitivity reported by patients, during or after the in-office tooth bleaching procedure.

Effect of two erosive protocols using acidic beverages on the shear bond strength of orthodontic brackets to bovine enamel.

OBJECTIVE: To assess the short-term effect of two in vitro erosive challenge protocols on the bond strength of metal orthodontic brackets on bovine enamel. METHODS: Sixty bovine incisors were selected and randomly divided into six groups: AS7 (artificial saliva - 7 days, Control Group); CC7 (Coca-Cola™ - 7 days); LJ7 (lime juice - 7 days); AS30 (artificial saliva - 30 days, Control Group); CC30 (Coca-Cola™ - 30 days); LJ30 (lime juice - 30 days). Microhardness testing was performed prior to the erosive challenge to verify the standardization of samples. Immersion was performed 4x/day for five minutes, for either 7 or 30 days. After immersions were concluded, the brackets were bonded and shear bond strength was assessed after 48 hours. The Adhesive Remnant Index (ARI) was also assessed. Data were analyzed by two-way ANOVA, followed by Tukey's post-hoc and Student's t test for paired samples, and the Kruskal-Wallis non-parametric test (α = 5%). RESULTS: The mean and standard deviation of microhardness testing of total samples were 281.89 ± 44.51 KHN. There was no statistically significant difference in shear bond strength for the time factor (7 or 30 days; F5.54= 0.105; p  = 0.901). However, there was a statistically significant difference for the solution factor (F5.54= 6.671; p  = 0.003). These differences occurred among solutions of Saliva x Coca-Cola™ (p  = 0.003) and Coca-Cola™ x Lime Juice (p = 0.029). The assessment of the Adhesive Remnant Index showed no significant difference between groups. CONCLUSIONS: The immersion time used in the erosion protocols did not affect the bond strength of brackets to teeth. Coca-Cola™ induced significantly higher shear bond strength values than lime juice and artificial saliva. However, the short term effects of 7/30 days in this in vitro study may not be extrapolated for in vivo ones. Clinical studies should be conducted, substantiating the laboratory results.

Preemptive use of etodolac on tooth sensitivity after in-office bleaching: a randomized clinical trial

Abstract Purpose: This study determined the effectiveness of the preemptive administration of etodolac on risk and intensity of tooth sensitivity and the bleaching effect caused by in-office bleaching using 35% hydrogen peroxide. Material and methods: Fifty patients were selected for this tripleblind, randomized, crossover, and placebo-controlled clinical trial. Etodolac (400 mg) or placebo was administrated in a single-dose 1 hour prior to the bleaching procedure. The whitening treatment with 35% hydrogen peroxide was carried out in two sessions with a 7-day interval. Tooth sensitivity was assessed before, during, and 24 hours after the procedure using the analog visual scale and the verbal rating scale. Color alteration was assessed by a bleach guide scale, 7 days after each session. Relative risk of sensitivity was calculated and adjusted by session, while overall risk was compared by the McNemar's test. Data on the sensitivity level of both scales and color shade were subjected to Friedman, Wilcoxon, and Mann-Whitney tests, respectively (α=0.05). Results: The preemptive administration of etodolac did not affect the risk of tooth sensitivity and the level of sensitivity reported, regardless of the time of evaluation and scale used. The sequence of treatment allocation did not affect bleaching effectiveness, while the second session resulted in additional color modification. The preemptive administration of etodolac in a single dose 1 hour prior to in-office tooth bleaching did not alter tooth color, and the risk and intensity of tooth sensitivity reported by patients. Conclusion: A single-dose preemptive administration of 400 mg of etodolac did not affect either risk of tooth sensitivity or level of sensitivity reported by patients, during or after the in-office tooth bleaching procedure.

Thermal-induced polymerization shrinkage in silorane versus methacrylate based resin composite / Contração de polimeração induzida termicamenteem resinas compostas a base de silorano e metacrilato

Shrinkage is a limitation of resin composite, compromising the clinical longevity of the restorative procedure. In an attempt to reduce their harmful effects, researchers have studied monomers with lower values of contraction. As a result, low-shrinkage composites were developed. This study evaluated quantitatively the shrinkage as a function of power density increase based on methacrylates, comparing them with silorane based resin, and qualitatively regarding gap formation between the adhesive interface as function of tooth substrate. Resin Filtek P90 and Filtek Z250 were polymerized with the device Blue Star 3 with 200, 400, 600, 800 and 1000 mW/cm2 keeping volume constant in 12 mm3. For qualitative analysis of restorative interface, class V cavity preparations in bovine incisors were restored in (2x2x2 mm3), photoactivated with the same values of irradiance, and analyzed by scanning electron microscopy at the interface of the wall surrounding enamel, dentin and axial. The quantitative results of the polymerization shrinkage were analyzed by two-way ANOVA and Tukey's test (p<0.05), while qualitative data were submitedd to Mann-Whitney's, Kruskal-Wallis' and Miller's tests. The progressive increase in power density directly influenced the polymerization shrinkage of the materials studied, although the silorane based resin demonstrated significantly lower values. The marginal integrity was influenced by the dental substrate and the power density used.

Este estudo avaliou quantitativamente a contração de polimerização em função do aumento dos valores de densidade de potência irradiados em compósitos à base de metacrilatos e silorano, e qualitativamente a interface restauradora em relação à abertura de fendas marginais, em função da variação do tipo de substrato dentário. As resinas Filtek Z250 e Filtek P90 foram fotoativadas com 200, 400, 600, 800 e 1000 mW/cm2, em um volume constante de 12mm3, e os valores de contração foram aferidos por meio da máquina de ensaios universal. Para análise qualitativa da interface restauradora, preparos cavitários classe V de (2x2x2mm3) foram restaurados em incisivos bovinos, fotoativados com os mesmos valores de irradiância, e analisados em microscopia eletrônica de varredura nas interfaces da parede circundante em esmalte, parede circundante em dentina e parede axial. Os resultados quantitativos da contração de polimerização foram analisados pelo teste ANOVA a dois critérios e Tukey (p<0,05) enquanto para os dados qualitativos os testes Mann- Whitney, Kruskal-Wallis e Miller foram empregados. O aumento progressivo da densidade de potência influenciou diretamente na contração de polimerização dos materiais estudados, não obstante a resina composta à base de silorano ter demonstrado valores significativamente menores. A integridade marginal sofreu influência do substrato dentário bem como da densidade de potência utilizada, para as duas resinas estudadas.

Noninvasive esthetic treatment for hypomaturation amelogenesis imperfecta: a case report.

Enamel alterations, such as amelogenesis imperfecta, can compromise the harmony of the smile and the patient's self-esteem and may cause tooth sensitivity. A simple and effective treatment approach uses the natural stratification of composite resins to mask deficient enamel formation and mimic the natural appearance of the substrate. The operative steps and principles for restorative success are described in this case report with 36-month follow-up.

Polishing techniques effect on microhybrid, nanohybrid and nanofilled composites color and surface roughness stability / Efeito de técnicas de polimento na estabilidade da cor e rugosidade superficial de resinas compostas microhibridas nanohibridas e nanoparticuladas

Resin roughness and staining is a common problem in dentistry. Objective: the aim of this study was to verify the influence of single and multiple-steps polishing techniques on color stability and surface roughness of differents composite resins. Groups were (n=10): FS+CS. Filtek Supreme XT + clear strip; FS+PG. Filtek Supreme XT+PoGo; FS+SF. Filtek Supreme XT+Sof-Lex; AM+CS. Amelogen+clear strip; AM+PG. Amelogen+PoGo; AM+SF. Amelogen+Sof-Lex; TEC+CL .TetricEvoCeram + clear strip; TEC+PG .Tetric EvoCeram+ PoGo; TEC+SF .Tetric EvoCeram+Sof-Lex; CED+CS .Ceram X Duo+clear strip; CED+PG. Ceram X Duo+PoGo; CED+SF. Ceram X Duo+Sof- Lex. The initial color and roughness were determined before and after the polishing procedures. All specimens were stored for 7 days in coffee solution and the color assessment was performed. Two specimens from each group were evaluated by scanning electron microscopy. Roughness and color data were submitted to ANOVA and Tukey tests(p<0.05). All tested materials presented color alterations after coffee solution storage; the highest E values were observed for clear strips and all composite resins, as following: G4 (9h)>G7(5.8f)=G10(5.7ef)>G1(3.7c), followed by the G6(5.9f)>G9(3.1bc)=G12(2.1ab)>G3(1.7a). G3, after 7 days, presented the lowest values for E(1.704). The lowest roughness values were observed when the clear strips were used regardless material type. The Sof-Lex system provided the lowest surface roughness values for all tested composite resins. Among composite resins the highest roughness values were found for Amelogen (G5­0.49 and G6­0.35), regardless polishing technique. All tested materials presented changes in color after immersion in coffee solution. The roughness surface and the staining of composite resins are material and polishing technique dependents.

Rugosidade e pigmentação de resinas são problemas comuns em odontologia. Objetivo: Avaliar influência das técnicas de um e múltiplos-passos de polimento na estabilidade de cor e rugosidade de resinas. Os grupos (n=10): G1.Filtek Supremo XT+Tira poliéster; G2.Filtek SupremeXT+PoGo; G3.Filtek Supreme XT+ Sof-Lex; G4.Amelogen+Tira poliéster; G5.Amelogen + PoGo; G6.Amelogen + Sof-Lex; G7.Tetric EvoCeram +Tira poliéster; G8.Tetric EvoCeram+PoGo; G9.Tetric EvoCeram+Sof-Lex; G10.CeramXDuo+Tira poliéster; G11.Ceram X Duo+PoGo; G12.Ceram X Duo+Sof-Lex. A Cor inicial e rugosidade foram determinadas antes e apóso polimento. Após, foram armazenadas durante 7 dias em solução de café e nova avaliação da cor foi realizada. Dois espécimes de cada grupo foram avaliados pela microscopia eletrônica de varredura. Dados de rugosidade e cor foram submetidos à ANOVA e teste Tukey (p <0,05). Todas as resinas testadas apresentaram alterações de cor após armazenamento em solução de café; foram observados os maiores valores de AE em tiras de poliésterpara as resinas,a seguir: G4 (9h)>G7 (5,8f) = G10 (5,7ef)>G1 (3,7c), seguindo-se a G6 (5,9f)>9 (3,1bc)=G12 (2,1ab)>G3 (1,7a). G3, após 7 dias, apresentaram os menores valores para AE (1,704). Menores valores de rugosidade foram observados para as tiras de poliéster, independentemente do material. Menores valores de rugosidade foram encontrados no sistema Sof-Lex. Entre as resinas valores maiores de rugosidade foram encontrados para Amelogen (G5-0,49 e G6-0,35), para as duas técnicas. Todos os materiais testados apresentaram alterações na cor após imersão em solução de café. A rugosidade e pigmentação das resinas compostas são dependentes da técnica e material.

Variação da temperatura intra-câmara pulpar em função da ativação com LED de géis clareadores de uso ambulatorial / Variation of temperature in pulp chamber due to LED bleaching gels activation

Este estudo avaliou o efeito da aplicação de diferentes géis clareadores na temperatura intra-câmara pulpar no clareamento fotoativado em consultório. Preencheu-se a câmara pulpar de um incisivo com pasta térmica e um sensor digital Termopar, e a raiz submersa em água a 37°C. Avaliaram-se 6 grupos: G1- SG: sem gel; PH: G2- peróxido de hidrogênio incolor a 35%; G3- OXB: Opalescence Xtra Boost; G4- WHP: Whiteness HP; G5- WM: Whiteness HP MAXX; G6- LP: Lase Peroxide. Para a ativação dos géis empregou-se o aparelho LED por 3 minutos. A aferição da variação de temperatura intra-câmara foi realizada com termômetro digital com termopar tipo K a cada 30 segundos. Os dados foram submetidos à ANOVA a dois critérios e teste de Tukey. Os resultados foram: 60 s - O grupo G2 (38° C) apresentou menor valor que os demais; 90 s - G2 (38,8°C) < G6 (39,6°C), G3 (39,8°C); 120 s - G2 (38,8°C) < G3 (40°C), G4 (39,6°C), G5 (39,8°C), G6 (40°C); 150 s - G2 (39°C) < G1 (39,8°C) G3, G4, G5, G6 (40°C); 180 s. A média final obtida foi: G2 (38,72°C) < G5 (39,16°C) < G1 (39,27°C) < G4 (39,30°C) < G6 (39,33°C) < G3 (39,47°C). O gel incolor não promoveu aumento significante na temperatura intrapulpar; géis clareadores com corante vermelho e verde aceleram este aumento quando ativados por luz LED azul de alta densidade de energia...

This study has evaluated the effect of different dental bleaching gels over the pulp chamber temperature during in-office photoactivated dental bleaching. The empty pulp chamber of an incisor was filled with a heat sink compound and a thin digital K-type thermocouple, immersed in distilled water at 37°C. Six groups were evaluated: G1 with no gel; G2 colorless gel; G3- OXB: Opalescence Xtra Boost; G4- WHP: Whiteness HP; G5- WM: Whiteness HP MAXX; G6- LP: Lase Peroxide. The gel light activation was made using LED, during 3 consecutive minutes. The intra-pulpal temperature was measured using a digital thin K-type thermocouple K at every 30 seconds. Data were submitted to ANOVA and TukeyÆs test. Results showed: 60 s -G2 (38°C) showed lower value than the others; 90s -G2 (38.8°C) < G6 (39.6°C), G3 (39.8°C); 120 s - G2 (38.8°C) < G3 (40°C), G4 (39.6°C), G5 (39.8°C), G6 (40°C); 150 s - G2 (39°C) < G1 (39.8°C) G3, G4, G5, G6 (40°C); 180 s. The final mean obtained was: G2 (38,72°C) < G5 (39,16°C) < G1 (39,27°C) < G4 (39,30°C) < G6 (39,33°C) < G3 (39,47°C). The colorless gel did not provided significant increase in the pulp chamber temperature; bleaching gels with red and green dyes accelerate this increase in temperature when activated by blue LED light with high energy density...

Thirteen-year follow up of a conservative approach for closing diastema in anterior teeth with composite resin / Treze anos de acompanhamento clínico de restaurações conservativas de resina composta no fechamento de diastemas anteriores

Anterior multiple diastema is a problem when the objective is harmonic an smile. Composite resin direct adhesive restorations provide satisfactory esthetic and function with minimum wear of the dental structures. The treatment success depends mainly on good patient oral health, correct diagnosis and technique. This article describes the step by step of an multiple anterior diastema restoration by using composite resin to mimic the enamel and dentin, improving the smile's esthetic. This 13-year follow up shows imperceptible restorations that maintain the natural reproduction of the dental structures over the long term.

Diastemas anteriores múltiplos podem representar um problema na estética quando o objetivo é um sorriso harmonico. Restaurações de resina composta aplicadas de forma direta promovem função e estética satisfatórias, com o mínimo de desgaste da estrutura dental. O tratamento depende principalmente da boa higiene oral, de um correto diagnóstico e da técnica empregada. Este artigo descreve os passos de restaurar diastemas anteriores usando resinas compostas para mimetizar o esmalte e a dentina, otimizando a estética do sorriso. Este acompanhamento clínico de 13 anos demonstra as restaurações imperceptíveis que mantiveram a reprodução natural das estruturas dentárias ao longo do tempo.

Effect of preventive use of nonsteroidal anti-inflammatory drugs on sensitivity after dental bleaching: a systematic review and meta-analysis.

BACKGROUND: Tooth sensitivity associated with bleaching remains a challenge for clinicians. Inflammatory mediators released by the penetration of bleaching agents into dental tissues can sensitize nociceptors, leading to tooth sensitivity. TYPE OF STUDIES REVIEWED: In this systematic review, the authors included randomized clinical trials in which the investigators compared the preventive use of nonsteroidal anti-inflammatory drugs (NSAIDs) with a placebo for sensitivity after dental bleaching. The authors included only studies in which the investigators evaluated in-office tooth bleaching with high-concentration hydrogen peroxide and reported the risk or the level of tooth sensitivity after bleaching. RESULTS: The authors included 3 studies and evaluated the levels of sensitivity reported at up to 1 hour after the procedure and from 1 to 24 hours after bleaching. The authors also calculated the pooled relative risk for the effect of preventive use of NSAIDs on sensitivity after dental bleaching. Preventive analgesia with NSAIDs did not have a significant effect on the risk of sensitivity after dental bleaching or on the levels of sensitivity reported by patients. PRACTICAL IMPLICATIONS: There is insufficient evidence about the use of NSAIDs to prevent tooth sensitivity caused by in-office bleaching procedures.

Multidisciplinary esthetic approach for multiple anterior diastema: 36-month clinical performance / Abordagem estética multidisciplinar para múltiplos diastemas anteriores: desempenho clínico de 36 meses

The presence of diastema, between anterior teeth, distorts a pleasing smile by concentrating the observer’s attention on the spaces. The patient’s needs and expectations must be considered in the process of treatment planning to ensure satisfaction with the treatment out comes. There are many forms of therapy that can be used for diastema closure. A carefully developed diagnosis, which includes a determination of the causal element sand advanced treatment planning, allows the mostappropriate treatment to be selected for each case. The aim of this paper is to present a multidisciplinary approach as a solution to multiple diastemata in the anterior region using gingival tissue recontouring and direct adhesive restorations, with minimumwear of the dental structure, after the orthodontic intervention, discussing the minimal intervention toobtain imperceptive and aesthetic final restoration. Thirty-six months after the treatment was carriedout, the final aesthetic was maintained with all dental element details and gingival tissue harmony, without recurrence of periodontal pockets and the preservation of the tooth color and shape...

A presença de diastemas, entre dentes anteriores, distorce um sorriso agradável, concentrando a atenção do observador para os espaços. As necessidades e expectativas do paciente devem ser consideradas no processo de planejamento para garantir a satisfação no resultado do tratamento. Existem muitas formas de tratamento que podem ser utilizadas para o fechamento de diastemas. Um diagnóstico desenvolvido cuidadosamente, que inclui a determinação dos elementos causais e planejamento avançado do tratamento, permite as eleção do tratamento mais adequado para cada caso. O objetivo deste artigo é apresentar uma abordagem multidisciplinar como solução para diastemas multiplos na região anterior usando o recontorno gengival e restaurações adesivas diretas, com mínimo desgaste da estrutura dental, após a intervenção ortodôntica discutindo a intervenção mínima para a obtenção de restaurações finais estéticas e imperceptiveis. Trinta e seis meses após o tratamento foi avaliado, a estética final foi mantida com os detalhes do elemento dental e harmonia tecido gengival, sem recorrência de bolsas periodontais e preservando a cor e forma dos dentes...