ABSTRACT: The objective of this study was to evaluate the color alteration of four brands of artificial teeth (Art Plus, Trilux, Bionote and Biolux), after immersion in color solutions of coffee, red wine and urucum. We used 80 artificial teeth, which were standardized with 2 mm thickness. Then, they were subjected to finishing and polishing, and divided into 4 groups (n = 05), which were immersed in one of the 3 types of dye, plus distilled water (control). The samples were immersed daily for 4 hours, then they were removed, washed in tap water, dried with absorbent paper and immersed in distilled water for the subsequent hours in a biological glasshouse at 37 ºC, for 21 days. The evaluation of the color change was made in the periods of 0, 7, 14 and 21 days, by means of the tristimulus colorimeter. The data were subjected to the ANOVA and Tukey test with a 5 % significance. The results showed that the urucum was the substance that caused the greatest staining while the coffee and the wine did not show statistical difference. Regarding trademarks, Trilux presented a statistical difference compared to the other commercial brands, revealing colorimetric alteration only in the 14-day period. It was concluded that the composition of the artificial teeth, the type of pigmenting agent and the immersion time determine the color change.

RESUMEN: El objetivo de este estudio fue evaluar la alteración de color de cuatro marcas de dientes artificiales (Art Plus, Trilux, Bionote y Biolux), después de inmersión en soluciones colorantes de café, vino tinto y urucum. Se utilizaron 80 dientes artificiales, los cuales fueron estandarizados con 2 mm de espesor. En seguida, los mismos fueron sometidos al acabado y pulido, y divididos en 4 grupos (n = 5), los cuales fueron inmersos en uno de los 3 tipos de colorante, más agua destilada (control). Las muestras permanecieron inmersas diariamente durante 4 horas, luego fueron retiradas, lavadas en agua corriente, secas con papel absorbente e inmersas en agua destilada por las horas subsiguientes en invernadero biológico a 37 ºC, por 21 días. La evaluación del cambio de color se realizó en los períodos de 0, 7, 14 y 21 días, por medio del colorímetro tristimulo. Los datos fueron sometidos a la prueba ANOVA y Tukey con un 5 % de significancia. Los resultados demostraron que el urucum fue la sustancia que provocó mayor manchado mientras que el café y el vino no presentaron diferencia estadística. En cuanto a las marcas comerciales, el Trilux presentó una diferencia estadística en comparación con las otras marcas comerciales, revelando alteración colorimétrica sólo en el período de 14 días. Se concluyó que la composición de los dientes artificiales, el tipo de agente pigmentante y el tiempo de inmersión determinan el cambio de color.

An increase in dentin roughness, associated with surface composition, contributes to bacterial adherence in recontaminations. Surface roughness is also important for micromechanical interlocking of dental materials to dentin, and understanding the characteristics of the surface is essential to obtain the adhesion of root canal sealers that have different physico-chemical characteristics. OBJECTIVES: To evaluate the effects of sodium hypochlorite (NaOCl), ethylenediaminetetraacetic (EDTA), etidronic (HEBP), and citric acid (CA) associated with different irrigation regimens on root dentin roughness. MATERIAL AND METHODS: Forty-five root halves of anterior teeth were used. The root parts were sectioned in thirds, embedded in acrylic resin and polished to a standard surface roughness. Initially, the samples of each third were randomly assigned into 3 groups and treated as follows: G1 - saline solution (control); G2 - 5% NaOCl+18% HEBP mixed in equal parts; and G3 - 2.5% NaOCl. After initial measuments, the G3 samples were distributed into subgroups G4, G5 and G6, which were subjected to 17% EDTA, 10% CA and 9% HEBP, respectively. Following the new measuments, these groups received a final flush with 2.5% NaOCl, producing G7, G8 and G9. The dentin surface roughness (Ra) was determined before and after treatments using a profilometer. The Wilcoxon test (α<0.05) was used to compare the values before and after treatments, and the Friedman test (α<0.05) to detect any differences among root thirds. RESULTS: (i) NaOCl did not affect the surface roughness; (ii) there was a significant increase in roughness after the use of chelating agents (P<0.01); and (iii) only the G3 group showed a difference in surface roughness between apical third and other thirds of the teeth (P<0.0043). CONCLUSION: Only the irrigation regimens that used chelating agents altered the roughness of root dentin.

The present investigation observed the sealing ability of low shrinkage composite resins in large and deep cavities, placed and photocured in one increment. Large, deep cavities (5.0 mm diameter and 2.5 mm deep) surrounded by enamel were prepared in bovine teeth, which were then divided into five groups. Groups 1, 2, 3 and 4: acid conditioning + Adper Single Bond (3M/ESPE, St Paul, MN, USA) and restoration with Aelite LS Posterior (BISCO Inc. Schaumburg, IL, USA) (G1); Filtek Z-350 (3M/ESPE,St Paul, MN, USA) (G2); Filtek Z-350 Flow (3M/ESPE, St Paul, MN, USA) (G3); Premisa (KERR Corporation, Orange, CA, USA) (G4). Group 5: Silorane Adhesive system (3M/ESPE, St Paul, MN, USA) + restoration with Filtek Low Shrinkage Posterior P90 (3M/ESPE, St Paul, MN, USA). After polymerization, the teeth were immersed in 0.5% basic fuchsine solution and immediately washed. Using the Imagetool Software, the extent of dye along the margins was calculated as a percentage of total perimeter. The restorations were then transversally sectioned and the depth of dye penetration was calculated in mm, using the same software. Kruskal-Wallis analysis for all groups showed no statistical differences for extent (p = 0.54) or depth (p = 0.8364) of dye penetration. According to this methodology, the so-called low shrinkage composite resins had the same sealing ability compared to regular and flowable nanocomposite materials.

OBJETIVO: Avaliar a influência do uso de pontas ultra-sônica em diamante CVD e de pontas rotatórias convencionais na força adesiva do descanso para apoio de cíngulo em resina composta, confeccionadas sobre dentina de dente bovino. METODOLOGIA: Foram confeccionados 20 espécimes para cada grupo experimental. A exposição dentinária foi realizada com a ponta diamantada rotatória nos espécimes do Grupo 1 e com ponta diamantada CVD no Grupo 2. Em ambos os grupos foi utilizado um sistema adesivo autocondicionante de dois passos. A forma e o tamanho do descanso em resina composta foram padronizados com uma matriz de acetato. Os espécimes foram submetidos ao ensaio de cizalhamento em máquina de teste universal com velocidade constante de 0,5 mm/min. Os dados foram analisados por teste t de Student ao nível de significância de 0,05. RESULTADOS: O teste t-Student demonstrou diferença estatisticamente significante entre os grupos (P=0,028), com médias de 24 kgf para o grupo 1 e 31 kgf para o grupo 2. CONCLUSÃO: O preparo dental com exposição de dentina em região de cíngulo com ponta ultra-sônica CVD promoveu maior resistência de união do sistema adesivo autocondicionante com o descanso para apoio de cíngulo em resina composta para uso em prótese parcial removível.

PURPOSE: To evaluate the influence of using either ultrasonic CVD (Chemical Vapor Deposition) or conventional rotary diamond tips on the adhesive strength of cingulum rest seats made of composite resin over bovine dentin. METHODS: Twenty specimens were produced for each experimental group. For specimens in Group 1, the dentin was exposed with a rotary diamond tip; in Group 2 this procedure was performed using an ultrasonic CVD diamond tip. In both groups a two-step self-etching adhesive system was used, and the shape and size of the rest seats made of composite resin were standardized. The specimens were subjected to a shear assay using a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed by Student's t-test at the significance level of 0.05. RESULTS: There was a statistically significant difference (P=0.028) between the means of the experimental groups: 24 kgf for Group 1 and 31 kgf for Group 2. CONCLUSION: Dental preparation with dentin exposure in the cingulum region by using ultrasonic CVD diamond tip showed the highest bond strength of self-etching adhesive system and composite rest seats for support of removable partial dentures.

This study investigated the influence of bioactive materials on the dentin surface whitened. MATERIAL AND METHODS: Three bovine teeth were shaped into three dentin wafers. Each wafer was then sectioned, into six dentin slices. One slice from each tooth was distributed into one of 6 groups: 1.CG = control group (distilled water); 2.WT = whitening treatment; 3.WT + MI Paste Plus, applied once a day; 4.WT + Relief ACP30, applied once a day for 30 mintes; 5.WT + Relief ACP60, applied once a day for 60 minutes; 6.WT + Biosilicate®, applied once a week. All groups were treated over 14 days. RESULTS: CG presented all dentinal tubules occluded by smear layer; WT group was observed all dentinal tubules opened. In the groups 3, 4 and 6, tubules were occluded. Group 5, dentinal tubules were completely occluded by mineral deposits. CONCLUSION: The use of bioactive materials immediately after whitening treatment can reduce or even avoid the demineralization effect of whitening and avoid exposing dentinal tubules.

Este estudo teve o propósito de avaliar o nível de conhecimento de 150 alunos de graduação dos cursos de Odontologia e Educação Física acerca dos protetores bucais no município de Belém, Brasil. Além disso, objetivou-se promover maior informação a esses futuros profissionais, por meio de palestras e distribuição de folders, nas quais o foco principal eram os protetores bucais, suas indicações, seus tipos, sua higienização e armazenamento. Os participantes da pesquisa pertenciam ao último ano de seus referidos cursos de graduação. A análise dos resultados permitiu evidenciar que 68% dos alunos entrevistados ainda não possuem informação adequada acerca dos protetores bucais, mas que, apesar disso, em sua maioria são conscientes quanto aos riscos a que vários atletas são submetidos em esportes que exigem impacto físico. Os autores acreditam que é extremamente importante que haja maior divulgação da importância da utilização de protetores bucais na prática esportiva, visando a prevenção e a promoção de saúde da população em geral.

This study had the aim to assess the level of knowledge of 150 Odontology and Physical Education undergraduation students concerning mouth guards in the city of Belém, Brazil. Besides that, we tried to provide further information to these future professionals through speeches and distribution of folders in which the main focus was the mouth guards, their indications, types as well as hygienization and storage. The participants in the research were in the last year of their specific undergraduation courses. The analysis of the results showed that 68% of the interviewed students still do not have suitable information on the mouth guards, but despite of that, in their majority they are aware of the risks many athletes face in sports which have physical impact. The authors believe the spread of the information on the use of mouth guards in sportive practice is relevant and aims to prevent trauma and promote health of general population.