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1.
Shanghai Kou Qiang Yi Xue ; 29(3): 312-315, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-33043351

RESUMO

PURPOSE: To compare the aesthetic effects of all-ceramic micro-veneer and minimally invasive ultra-thin veneer in repairing deformed anterior teeth. METHODS: One hundred and twenty patients with deformed anterior teeth were selected for aesthetic restoration. According to the patient's personal condition, a suitable repair protocol was selected. Patients in the experimental group (60 cases) were repaired with all-ceramic micro-adhesive surface, while patients in the control group (60 cases) were treated with minimally invasive ultra-thin veneer. The US Public Health Administration's Evaluation Criteria (USPHS) scores were recorded and compared 6 months, 12 months, and 24 months after restoration. Statistical analysis was performed using SPSS 25.0 software package. RESULTS: There was no significant difference in the integrity, color, marginal closeness, translucency and marginal staining of the restorations between the two groups 24 months after operation (P>0.05). The satisfaction rate of the aesthetics of the experimental group was significantly lower than that of the control group (71.60% vs 93.83%, P<0.05). The incidence of complications such as broken, detached and secondary caries during the follow-up period was significantly lower in the experimental group than in the control group (1.23% vs 11.11%, P<0.05). CONCLUSIONS: The results showed that there is no significant difference in the success rate between the two methods. All-ceramic micro-veneer technique has good long-term effect, fewer complications, easy to collapse and stain the lip margin, but it has a small amount of teeth preparation and a low incidence of pulpitis in the later period. Minimally invasive super-thin veneer has high aesthetic value, so it is necessary to choose appropriate aesthetic repair methods according to the patients' needs.


Assuntos
Porcelana Dentária , Facetas Dentárias , Cerâmica , Cor , Estética Dentária , Humanos
2.
Proc Biol Sci ; 287(1934): 20201525, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32873200

RESUMO

Honeybees forage on diverse flowers which vary in the amount and type of rewards they offer, and bees are challenged with maximizing the resources they gather for their colony. That bees are effective foragers is clear, but how bees solve this type of complex multi-choice task is unknown. Here, we set bees a five-comparison choice task in which five colours differed in their probability of offering reward and punishment. The colours were ranked such that high ranked colours were more likely to offer reward, and the ranking was unambiguous. Bees' choices in unrewarded tests matched their individual experiences of reward and punishment of each colour, indicating bees solved this test not by comparing or ranking colours but by basing their colour choices on their history of reinforcement for each colour. Computational modelling suggests a structure like the honeybee mushroom body with reinforcement-related plasticity at both input and output can be sufficient for this cognitive strategy. We discuss how probability matching enables effective choices to be made without a need to compare any stimuli directly, and the use and limitations of this simple cognitive strategy for foraging animals.


Assuntos
Abelhas/fisiologia , Animais , Comportamento Animal , Comportamento de Escolha , Cor , Percepção de Cores , Simulação por Computador , Flores
3.
Proc Biol Sci ; 287(1934): 20201894, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32900312

RESUMO

Some camouflaged animals hide colour signals and display them only transiently. These hidden colour signals are often conspicuous and are used as a secondary defence to warn or startle predators (deimatic displays) and/or to confuse them (flash displays). The hidden signals used in these displays frequently resemble typical aposematic signals, so it is possible that prey with hidden signals have evolved to employ colour patterns of a form that predators have previously learned to associate with unprofitability. Here, we tested this hypothesis by conducting two experiments that examined the effect of predator avoidance learning on the efficacy of deimatic and flash displays. We found that the survival benefits of both deimatic and flash displays were substantially higher against predators that had previously learned to associate the hidden colours with unprofitability than against naive predators. These findings help explain the phenological patterns we found in 1568 macro-lepidopteran species on three continents: species with hidden signals tend to occur later in the season than species without hidden signals.


Assuntos
Aprendizagem da Esquiva , Pigmentação , Comportamento Predatório , Animais , Cor , Sinais (Psicologia) , Estações do Ano
4.
Proc Biol Sci ; 287(1935): 20201688, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32962546

RESUMO

Tarantulas paradoxically exhibit a diverse palette of vivid coloration despite their crepuscular to nocturnal habits. The evolutionary origin and maintenance of these colours remains mysterious. In this study, we reconstructed the ancestral states of both blue and green coloration in tarantula setae, and tested how these colours correlate with presence of stridulation, urtication and arboreality. Green coloration has probably evolved at least eight times, and blue coloration is probably an ancestral condition that appears to be lost more frequently than gained. While our results indicate that neither colour correlates with the presence of stridulation or urtication, the evolution of green coloration appears to depend upon the presence of arboreality, suggesting that it ptobably originated for and functions in crypsis through substrate matching among leaves. We also constructed a network of opsin homologues across tarantula transcriptomes. Despite their crepuscular tendencies, tarantulas express a considerable diversity of opsin genes-a finding that contradicts current consensus that tarantulas have poor colour vision on the basis of low opsin diversity. Overall, our findings raise the possibility that blue coloration could have ultimately evolved via sexual selection and perhaps proximately be used in mate choice or predation avoidance due to possible sex differences in mate-searching.


Assuntos
Opsinas , Pigmentação , Aranhas/fisiologia , Animais , Cor , Evolução Molecular , Comportamento Predatório , Opsinas de Bastonetes , Caracteres Sexuais
5.
Adv Exp Med Biol ; 1268: 381-385, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32918229

RESUMO

BACKGROUND: The rule of thumb "Fill up a handful of sunscreen and spread it all over your body" has been used in several sun safety campaigns. The intention was to increase the applied sunscreen to obtain a quantity of 2 mg/cm2 to all accessible skin. The present study is the first to investigate how this advice works in practice, evaluated by quantity of sunscreen applied and amount of covered skin. METHODS: Seventeen volunteers wearing swimwear were asked to "Fill up a handful and spread it all over your body." Before and after sunscreen application, the volunteers were photographed in black light. As sunscreen absorbs black light, the darkness of the skin increases with increasing amounts of applied sunscreen, making it possible to identify skin left without coverage. The sunscreen container was weighed before and after to quantify the amount of sunscreen applied. RESULTS: A median of 21% of the accessible skin was left completely without coverage. The 79% covered area was covered with a median of 1.12 mg/cm2, not the expected 2 mg/cm2. CONCLUSION: In practice, the advice "Fill up a handful of sunscreen and spread it all over your body" led to a better but still modest protection, compared to the intended effect.


Assuntos
Pele/metabolismo , Protetores Solares/administração & dosagem , Protetores Solares/análise , Administração Cutânea , Cor , Humanos , Protetores Solares/farmacocinética
6.
Int J Prosthodont ; 33(5): 487-492, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32956429

RESUMO

PURPOSE: The aim of the present study was to assess the perceptibility and acceptability threshold values for color differentiation at the restoration and mucosa levels. MATERIALS AND METHODS: One restored single-tooth implant and the contralateral reference tooth were spectrophotometrically assessed in 20 patients. Perceptibility and acceptability were evaluated by dentists, dental technicians, and laypeople. RESULTS: Dental technicians had the highest sensitivity in the perception of tooth color differences (ΔE = 2.7), followed by dentists (ΔE = 3.3) and laypeople (ΔE = 4.4). Acceptability threshold values were generally higher than perceptibility threshold in all groups. Dental technicians exhibited the highest sensitivity in the perception of mucosa color differences (50% perceptibility at ΔE = 2.65), followed by dentists (ΔE > 3.7) and laypeople (ΔE > 6). CONCLUSION: Color differences were tolerated with varying degrees among the three groups. Laypeople accepted higher color differences at the mucosa level.


Assuntos
Implantes Dentários para Um Único Dente , Dente , Cor , Percepção de Cores , Humanos , Membrana Mucosa
7.
Int J Prosthodont ; 33(5): 536-545, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32956435

RESUMO

PURPOSE: To evaluate the shear bond strength (SBS) and color stability (ΔE) of four ceramic veneers (VITA VM 9; VITA VM 13; VITA VMK 95; and IPS e.max Ceram) following repair with three different self-adhesive composite resins (Fusio Liquid Dentin; Constic; and Vertise Flow) and BISCO Intraoral Repair Kit + Filtek Supreme (BC + FS). MATERIALS AND METHODS: A total of 96 specimens were prepared per ceramic material, and each ceramic group was divided into subgroups according to testing method (32 specimens for color stability analysis and 64 specimens for SBS testing). ΔE and SBS (SBS1 = non-aged, SBS2 = thermally aged) values of the repaired specimens were calculated. One specimen from each of the thermally aged groups was investigated under scanning electron microscopy (SEM). Two-way ANOVA was used to analyze the mean ΔE, SBS1, and SBS2 values. The differences between SBS1 and SBS2 values were analyzed using independent-samples t test. RESULTS: The lowest ΔE values were calculated for Constic (P ≤ .05). The SBS2 values among all groups were lower than the SBS1 values (P ≤ .05). The lowest SBS2 values were observed for Vertise Flow (2.3 ± 1.47 MPa) (P ≤ .05) and were below the acceptable limit of 5 MPa. CONCLUSION: All of the investigated repair materials in combination with the ceramic veneers exhibited ΔE values that were higher than the clinically acceptable limits. Thermal aging negatively affected the SBS values in all groups (P ≤ .05). All tested self-adhesive composite resins, with the exception of Vertise Flow, could be used instead of a repair kit with flowable composite resin, especially in noncooperative patients, for the purpose of repairing chipping fractures for VITA VM 9, VITA VM 13, and VITA VMK 95 (P > .05).


Assuntos
Colagem Dentária , Cimentos Dentários , Resinas Acrílicas , Cerâmica , Cor , Resinas Compostas , Porcelana Dentária , Humanos , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície
8.
Acta Odontol Latinoam ; 33(2): 59-68, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920607

RESUMO

The aim of this in vitro study was to evaluate the effect of bleaching protocols on the surface roughness (Ra), color change and surface micromorphology of a low-viscosity bulk-fill composite (Filtek Bulk Fill Flow, 3M ESPE), a highviscosity bulk-fill composite (Filtek Bulk Fill, 3M ESPE) and a conventional nanoparticulate composite resin (control) (Filtek Z350 XT, 3M ESPE). Forty samples of each composite (disks 5 mm in diameter and 2 mm thick) were randomly divided into four groups (n=10), according to bleaching protocol: a) 10% carbamide peroxide gel (Opalescence, Ultradent Products) (2 h/ day, for 14 days); b) 40% hydrogen peroxide gel (Opalescence Boost, Ultradent Products) (three bleaching sessions, once a week, 45 min/session); c) whitening rinse (Listerine Whitening Extreme, Johnson & Johnson) (2 min/day, for 14 days); and d) distilled water (control). The samples were submitted to triplicate readings (Ra and color [CIELAB parameters]) before and after contact with bleaching protocols. Micromorphology was analyzed in a scanning electron microscope (SEM). Ra and color parameters (ΔL, Δa, Δb and ΔE) were analyzed by generalized linear models (α=0.05). The Ra of the high-viscosity bulk-fill was significantly higher than that of the other composites (p<0.05). Ra increased significantly (p<0.05) and surface became more irregular (SEM analysis) in all the composite resins, regardless of the bleaching protocol (p<0.05). The high-viscosity bulk-fill composite resin group had significantly lower ΔE (p<0.05) than the nanoparticulate composite resin group immersed in distilled water. It was concluded that the characteristics of each resin significantly influenced the Ra more than the bleaching protocol. The high-viscosity bulk-fill resin presented minor color change.


Assuntos
Resinas Compostas/química , Peróxido de Hidrogênio/química , Clareadores Dentários/química , Clareamento Dental/métodos , Descoloração de Dente/tratamento farmacológico , Viscosidade/efeitos dos fármacos , Cor , Humanos , Teste de Materiais
10.
Sci Total Environ ; 745: 141179, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32758748

RESUMO

Recent work has demonstrated that surface colour affects the formation of cyanobacterial subaerial biofilms on polycarbonate coupons and, in turn, influences their bioreceptivity. To explore whether colour is important on other substrates, the influence of colour on the primary bioreceptivity of granite to the terrestrial green alga Apatococcus lobatus (Trebouxiophyceae, Chlorophyta) has been assessed. Two granitoids (Grissal and Rosa Porriño) with the same texture, and very similar chemical composition, open porosity and surface roughness, but different coloration related to feldspars (i.e. greyish and reddish) were used to conduct bioreceptivity studies in parallel field and laboratory tests. Light microscopy, colour spectrophotometry, PAM fluorometry, and optical profilometry were used to evaluate colonisation and its impacts. Short-term results (after 7 and 10 weeks of colonisation by a mono-species biofilm) from both lab and field trials, showed significantly more algae growth on reddish granite (Rosa Porriño) than on greyish granite (Grissal). Also, optical profilometry and light microscopy demonstrated that on both granites algal aggregates developed in hollows. We attribute the roughly double levels of A. lobatus growth on reddish vs greyish granite to differences in the amount of radiant energy absorbed and the higher levels of red wavelength light (known to encourage algal growth) reflected from the reddish surface.


Assuntos
Clorófitas , Cor , Porosidade , Dióxido de Silício
11.
Int J Nanomedicine ; 15: 4959-4967, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764929

RESUMO

Background: Particle-based drug delivery systems (DDSs) have a demonstrated value for drug discovery and development. However, some problems remain to be solved, such as limited stimuli, visual-monitoring. Aim: To develop an intelligent multicolor DDSs with both near-infrared (NIR) controlled release and macroscopic color changes. Materials and Methods: Microparticles comprising GO/pNIPAM/PEGDA composite hydrogel inverse opal scaffolds, with dextran and calcium alginate hydrogel were synthesized using SCCBs as the template. The morphology of microparticle was observed under scanning electron microscopy, and FITC-dextran-derived green fluorescence images were determined using a confocal laser scanning microscope. During the drug release, FITC-dextran-derived green fluorescence images were captured using fluorescent inverted microscope. The relationship between the power of NIR and the drug release rate was obtained using the change in optical density (OD) values. Finally, the amount of drug released could be estimated quantitatively used the structural color or the reflection peak position. Results: A fixed concentration 8% (v/v) of PEGDA and 4mg/mL of GO was chosen as the optimal concentration based on the balance between appropriate volume shrinkage and structure color. The FITC-dextran was uniformly encapsulated in the particles by using 0.2 wt% sodium alginate. The microcarriers shrank because of the photothermal response and the intrinsic fluorescence intensity of FITC-dextran in the microparticles gradually decreased at the same time, indicating drug release. With an increasing duration of NIR irradiation, the microparticles gradually shrank, the reflection peak shifted toward blue and the structural color changed from red to orange, yellow, green, cyan, and blue successively. The drug release quantity can be predicted by the structural color of microparticles. Conclusion: The multicolor microparticles have great potential in drug delivery systems because of its vivid reporting color, excellent photothermal effect, and the good stimuli responsivity.


Assuntos
Portadores de Fármacos/química , Microesferas , Resinas Acrílicas/química , Alginatos/química , Cor , Dextranos/química , Liberação Controlada de Fármacos , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Hidrogéis/química , Fenômenos Ópticos , Polietilenoglicóis/química
12.
Ecotoxicol Environ Saf ; 202: 110939, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800222

RESUMO

Pulp and paper mill wastewater (PPMWW) contains high concentrations of recalcitrant compounds that cause toxicity to organisms. Advanced oxidation processes (AOPs) have the ability to degrade these compounds and reduce overall toxicity. Physicochemical characterization and Lactuca sativa toxicity test were conducted to compare the effectiveness of two post-treatments: UV/H2O2 and photo-Fenton. A comparison of four phytotoxicity indexes was carried out. PPMWW from a Brazilian treatment plant was characterized by high values of phenols, color, integrated spectral area (ISA), and chemical oxygen demand (COD), and caused significant inhibition to seedling development. The use of both post-treatments allowed the removal of over 75% of phenols, color, ISA, and COD. Although UV/H2O2 was more effective in removing phenols and ISA, photo-Fenton better reduced phytotoxicity. The most sensitive phytotoxicity indexes were RGIC0.8 and GIC80%, whereas SGC0, REC-0.25 and REC-0.50 better showed the effectiveness of the post-treatments. We suggest the combined use of two phytotoxicity indexes: one that evaluates the effects on seed germination and, another, on root elongation, e.g., SGC0 and RGIC0.8. Additionally, we recommend the use of ISA for monitoring programs of wastewater treatments because it is a cost-effective approach that allows narrowing down the search and identification of compounds present in complex mixtures.


Assuntos
Papel , Fenóis/toxicidade , Eliminação de Resíduos Líquidos/métodos , Análise da Demanda Biológica de Oxigênio , Brasil , Cor , Corantes/toxicidade , Peróxido de Hidrogênio/química , Resíduos Industriais/análise , Oxirredução , Fenóis/análise , Plantas/efeitos dos fármacos , Águas Residuárias/química
13.
N Engl J Med ; 383(9): 809-811, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32846059
14.
Physiol Plant ; 170(1): 7-9, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32830334

RESUMO

Cyanobacteria require light to perform photosynthesis, but not all colors of light are equally useable for them. In particular, blue light-grown cyanobacterial strains, including the well-studied model organism Synechocystis sp. PCC 6803 (Synechocystis), have been observed to exhibit slower growth rates than white or red light-grown cells. In this issue of Physiologia Plantarum, Luimstra et al. (2020) have attempted to understand why cyanobacterial cells suffer under blue light. They measured the molecular and genetic responses of Synechocystis cells to being shifted from white light to blue light. They found that blue light-grown cells make changes that lead to a redistribution of energy flow between the two photosystems that power photosynthesis. These findings could help researchers identify avenues for optimizing photosynthesis in cyanobacterial species, a group of organisms which show great promise as potential solar-powered factories for the production of biofuels and other high-value products.


Assuntos
Synechocystis , Biocombustíveis , Cor , Fotossíntese/genética
15.
Proc Biol Sci ; 287(1933): 20201521, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32811316

RESUMO

Of all hypotheses advanced for why zebras have stripes, avoidance of biting fly attack receives by far the most support, yet the mechanisms by which stripes thwart landings are not yet understood. A logical and popular hypothesis is that stripes interfere with optic flow patterns needed by flying insects to execute controlled landings. This could occur through disrupting the radial symmetry of optic flow via the aperture effect (i.e. generation of false motion cues by straight edges), or through spatio-temporal aliasing (i.e. misregistration of repeated features) of evenly spaced stripes. By recording and reconstructing tabanid fly behaviour around horses wearing differently patterned rugs, we could tease out these hypotheses using realistic target stimuli. We found that flies avoided landing on, flew faster near, and did not approach as close to striped and checked rugs compared to grey. Our observations that flies avoided checked patterns in a similar way to stripes refutes the hypothesis that stripes disrupt optic flow via the aperture effect, which critically demands parallel striped patterns. Our data narrow the menu of fly-equid visual interactions that form the basis for the extraordinary colouration of zebras.


Assuntos
Dípteros , Pigmentação , Animais , Cor , Sinais (Psicologia) , Voo Animal , Mordeduras e Picadas de Insetos
16.
Water Sci Technol ; 81(12): 2664-2673, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32857751

RESUMO

Horseradish peroxidase (HRP) characteristics were improved by two techniques, Na-alginate entrapment and glutaraldehyde crosslinking prior to alginate entrapment, in order to enhance the stability, functionality and removal of dyes in waste water. Free, entrapped and crosslinked-entrapped enzymes were compared by activity assays, which indicated the optimum temperature is 25 °C and pH 4.0-5.0. Kinetics results showed that alginate entrapment and crosslinking prior to entrapment increased Vmax and did not cause any significant decrease in Km. The thermal resistance of the free enzyme was short-term, zero residual activity after 250 min, while the immobilized enzymes preserved more than 50% of their activity for 5 h at 60 °C. Immobilized HRP was resistant to methanol, ethanol, DMSO and THF. The storage stability of free HRP ended in 35 days whereas entrapped and crosslinked-entrapped HRPs had 87 and 92% residual activity at the 60th day, respectively. HRP was used in the decolorization of azo dye Acid yellow 11 and total decolorization (>99%) was obtained using crosslinked-entrapped HRP. Reusability studies presented the improvement that crosslinked-entrapped HRP reached 74% decolorization after 10 batches. The results demonstrated that the novel immobilized HRP can be used as an effective catalyst for dye degradation of industrial waste effluents.


Assuntos
Compostos Azo , Enzimas Imobilizadas , Cor , Corantes , Peroxidase do Rábano Silvestre , Concentração de Íons de Hidrogênio , Cinética , Temperatura
17.
An Acad Bras Cienc ; 92(suppl 1): e20180889, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32756837

RESUMO

Brown leaf spot disease, caused by the fungus Ragnhildiana diffusa, is responsible for losses in pecan orchards and quantification is essential in order to conduct epidemiological studies to establish levels of productivity losses, and assess control strategies. Therefore, the aim of this study was to develop and validate a diagrammatic scale for assessing the severity of brown leaf spot in pecan. 240 symptomatic leaflets were collected from adult trees in Anta Gorda, in the Brazilian state of Rio Grande do Sul, and used to assess the current percentage severity of the disease. The scale was based on the minimum and maximum observed severity of the disease, with six graduations defined according to the Weber-Fechner Visual Stimulus Law. The scale therefore consisted of eight levels (1.5, 4.6, 10.6, 17.3, 39.5, 65.1, 77.5, and 98%). The estimates of eight evaluators provided a basis for validating the scale. They made estimates of disease severity on 40 symptomatic digitalized pecan leaflets first, without using the scale and then referring to it. The scale provided greater precision, accuracy, and reproducibility of estimates and should result in more reliable epidemiological studies.


Assuntos
Carya , Ascomicetos , Cor , Folhas de Planta , Reprodutibilidade dos Testes , Árvores
18.
PLoS One ; 15(8): e0237854, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853262

RESUMO

Drug-induced long QT syndrome (diLQTS), characterized by a prolongation of the QT-interval on the electrocardiogram (ECG), is a serious adverse drug reaction that can cause the life-threatening arrhythmia Torsade de Points (TdP). Self-monitoring for diLQTS could therefore save lives, but detecting it on the ECG is difficult, particularly at high and low heart rates. In this paper, we evaluate whether using a pseudo-colouring visualisation technique and changing the coordinate system (Cartesian vs. Polar) can support lay people in identifying QT-prolongation at varying heart rates. Four visualisation techniques were evaluated using a counterbalanced repeated measures design including Cartesian no-colouring, Cartesian pseudo-colouring, Polar no-colouring and Polar pseudo-colouring. We used a multi-reader, multi-case (MRMC) receiver operating characteristic (ROC) study design within a psychophysical paradigm, along with eye-tracking technology. Forty-three lay participants read forty ECGs (TdP risk n = 20, no risk n = 20), classifying each QT-interval as normal/abnormal, and rating their confidence on a 6-point scale. The results show that introducing pseudo-colouring to the ECG significantly increased accurate detection of QT-interval prolongation regardless of heart rate, T-wave morphology and coordinate system. Pseudo-colour also helped to reduce reaction times and increased satisfaction when reading the ECGs. Eye movement analysis indicated that pseudo-colour helped to focus visual attention on the areas of the ECG crucial to detecting QT-prolongation. The study indicates that pseudo-colouring enables lay people to visually identify drug-induced QT-prolongation regardless of heart rate, with implications for the more rapid identification and management of diLQTS.


Assuntos
Eletrocardiografia , Frequência Cardíaca , Síndrome do QT Longo/diagnóstico por imagem , Síndrome do QT Longo/fisiopatologia , Adulto , Cor , Movimentos Oculares/fisiologia , Feminino , Fixação Ocular/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação Pessoal , Estimulação Luminosa , Psicofísica , Curva ROC , Tempo de Reação , Fatores de Risco , Sensibilidade e Especificidade , Adulto Jovem
19.
Int J Esthet Dent ; 15(3): 306-316, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760925

RESUMO

The aim of this study was to evaluate, in vivo, the immediate masking effect of white spot lesions (WSLs) treated with an infiltrant resin (IR). The investigation was conducted on 40 young adolescent and adult patients (11 to 23 years old) who presented with at least one permanent maxillary or mandibular anterior tooth with active WSLs on the enamel (ICDAS score 2). Before resin infiltration, the color of both the WSLs and the sound adjacent enamel (SAE) was evaluated by a digital spectrophotometer (CIELab). Subsequently, a resin infiltration technique (Icon) was performed on the WSLs according to the manufacturer's instruction. At the end of the clinical session, the color of the IR was evaluated. The color difference (ΔE) was calculated between WSL × SAE, WSL × IR, and IR × SAE, and then analyzed using one-way analysis of variance (ANOVA), followed by the Tukey's test. The L*, a*, and b* values of WSL, SAE, and IR were compared using the Student's t test for related samples (α = 5%). The ΔE observed was 5.93 ± 0.41 on the WSL × IR comparison, and 5.77 ± 0.41 on the IR × S AE one, indicating that the color of the WSL changed after treatment, but that the infiltration did not fully camouflage the WSLs when compared with the SAE. The lightness was higher for the SAE than for the IR. It was concluded that the IR treatment was not able to camouflage the color of the WSLs when compared with the SAE. However, the treatment was able to attenuate the discoloration of the demineralized dental enamel.


Assuntos
Cárie Dentária , Esmalte Dentário , Adolescente , Adulto , Criança , Cor , Humanos , Resinas Sintéticas , Espectrofotometria , Adulto Jovem
20.
Int J Esthet Dent ; 15(3): 318-332, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760926

RESUMO

OBJECTIVE: The fluorescence properties of tooth-colored restorative materials can vary according to the shade of the material. The objective of this study was to investigate the fluorescence behavior of different shades of selected contemporary tooth-colored restorative materials when illuminated with violet light (405 nm wavelength). METHODS: Fifteen different tooth-colored restorative materials, in total 111 shades, were analyzed. Samples of 10-mm diameter and 5-mm thickness were fabricated for each shade. The levels of red, blue, green, and luminosity were analyzed for each sample under 405 nm illumination and an orange long pass filter, using data from the histogram tool in Adobe Photoshop software. RESULTS: There were significant variations in fluorescence luminosity according to both shade and manufacturer. Within any one brand of material, fluorescence emissions differed according to shade, with the lightest shades giving the strongest emissions. Variations in fluorescence were most prominent for composite resins, followed by ormocers, and then glass-ionomer materials. There were also significant variations in fluorescence luminosity between materials of the same shade made by different manufacturers. CONCLUSION: Fluorescence emissions vary considerably among different shades of the same material, and between different materials that are labelled as having the same shade. In the present study, the lightest shades had the greatest emissions under UV light.


Assuntos
Resinas Compostas , Restauração Dentária Permanente , Cor , Materiais Dentários , Fluorescência , Teste de Materiais
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