RESUMO
Data-independent acquisition (DIA) allows comprehensive proteome coverage, while it also potentially works as a unified protocol to determine a multitude of proteins found in blood. Because of its high specificity, mass spectrometry may greatly reduce the interference observed in other assays to evaluate blood markers. Here, we combined DIA with volumetric absorptive microsampling (VAMS) and automated proteomics sample processing in a platform to assess clinical markers. As a proof of concept, we evaluated two hemoglobin-related biomarkers: the glycated hemoglobin (HbA1c) and hemoglobin (Hb) variants. HbA1c by DIA showed good correlation with the reference method, but method imprecision did not meet the quality requirement for this biomarker. We developed a strategy to identify Hb variants based on a customized database combined with a workflow for DIA data extraction and rigorous peptide evaluation. Data are available via ProteomeXchange with identifier PXD029918.
Assuntos
Coleta de Amostras Sanguíneas , Teste em Amostras de Sangue Seco , Biomarcadores , Coleta de Amostras Sanguíneas/métodos , Teste em Amostras de Sangue Seco/métodos , Hemoglobinas Glicadas , Espectrometria de Massas/métodosRESUMO
In this study, we sought to evaluate the influence of cigarette smoke and pH cycling on the chemical composition and surface/cross-sectional enamel microhardness. A total of 40 dental blocks obtained from bovine incisors were divided into four groups (n=10): no treatment (control); exposure to cigarette smoke (CS); exposure to pH cycling (PC); and exposure to cigarette smoke and pH cycling (CS-PC). The samples were analyzed by synchrotron radiation micro X-ray fluorescence, bench mode X-ray fluorescence, as well as surface microhardness (SMH) and cross-sectional microhardness (CSMH) testing. The SMH results were submitted to analysis of variance (ANOVA) and Tukey's test. The CSMH results were evaluated using split-plot ANOVA and Tukey's test. A high amount of Cd and Pb and traces of Ni and As were observed in enamel and dentin after exposure to cigarette smoke (CS and CS-PC). The SMH and CSMH of CS were statistically higher when compared with the control. The PC and CS-PC showed lower SMH and CSMH. We conclude that exposure to cigarette smoke promoted heavy metal deposition in enamel/dentin. In addition, it increased the enamel microhardness but did not promote a protective effect on the in vitro development of caries. The clinical significance of this work is that there is significant bioaccumulation of heavy metals from cigarette smoke on the surface and in the enamel and dentin.
RESUMO
In-office bleaching is a treatment based on products that contain hydrogen peroxide (HP) while demonstrating whitening effectiveness. HP could promote alterations to surface morphologies and properties of dental tissues. The objective was describe a toothpaste protocol associated to bleaching therapy to promote a safer approach. Patient 1 (male) and Patient 2 (female) were attended, and toothbrushing (twice a day) with a dentifrice containing bioactive glass (BG) (NovaMin™) and fluoride was indicated before and during the treatment. Three bleaching sessions were made in cases, at intervals of 7 days. The gels used were 35% HP (Patient 1) and 35% HP supplied with calcium (Patient 2). The effectiveness of bleaching treatment was observed in both cases (Vita scale), with an esthetic self-acceptance. Sensitivity associated with the procedure was not reported. The indication of BG-based toothpaste is relevant in relation to enamel properties and did not affect the whitening effectiveness of dental bleaching.
RESUMO
AIM: In the present study, we evaluated the efficacy of bleaching on enamel and opposite dentin surfaces using 35% hydrogen peroxide (HP) with the prior application of a desensitizing agent. METHODS: Thirty bovine dental fragments, with thicknesses of 1 mm enamel and 1.75 mm dentin, were stained in a solution of black tea. The fragments were randomly divided into three groups (n = 10) according to the following protocols: (a) 2% neutral fluoride + bleaching; (b) desensitizing agent + bleaching; and (c) without desensitizer + bleaching. The bleaching efficacy was evaluated four times: after staining with tea (baseline) and after each of the 3 weeks of bleaching, by means of the CIE Lab method using a reflectance spectrophotometer. The data coordinate L* was evaluated by an analysis of repeated measures with PROC MIXED and Tukey-Kramer's test. The ΔE values were subjected to anova and Tukey's test (α = 0.05). RESULTS: The 35% HP treatment showed greater efficacy on deep dentin after removal of the enamel stains, with increasing means during all times in all treatments. CONCLUSION: The use of a desensitizing agent prior to the bleaching session did not affect the mechanism of action of 35% HP with regard to tooth depth.
Assuntos
Esmalte Dentário/efeitos dos fármacos , Dessensibilizantes Dentinários/uso terapêutico , Dentina/efeitos dos fármacos , Peróxido de Hidrogênio/uso terapêutico , Clareadores Dentários/uso terapêutico , Clareamento Dental/métodos , Animais , Bovinos , Cor , Esmalte Dentário/ultraestrutura , Fluoretos/uso terapêutico , Microscopia Eletrônica de Varredura , Nitratos/uso terapêutico , Compostos de Potássio/uso terapêutico , Distribuição Aleatória , Fluoreto de Sódio/uso terapêutico , Espectrofotometria/métodos , Chá , Fatores de Tempo , Descoloração de Dente/tratamento farmacológicoRESUMO
AIM: In the present study, we evaluated the influence of the photo-curing delay time and energy density on the degree of conversion and the Knoop microhardness of a resin cement. METHODS: Seventy-eight samples were assigned to 13 groups (n = 6), one of which received no light curing (control). The samples were made of a dual-cured resin cement (RelyX ARC) with the aid of a Teflon matrix, submitted to one of the following energy densities (J/cm²): 7, 14, 20, and 28. Delay times were immediate (0), 1 min, or 2 min. After 24 h, the degree of conversion and microhardness were measured at three segments: cervical, medium, and apical. Data were submitted to three-way anova and Tukey's and Dunnett's tests, the latest of which was used to compare the control to the experimental groups. RESULTS: No interaction was observed between delay time and energy density regarding the degree of conversion. The cervical segment showed the highest values, while the apical showed the lowest. Microhardness values concerning the cervical segment in all groups were statistically different from that obtained for the control. CONCLUSION: A high-irradiance light-curing unit allows for a reduced irradiation exposure time with a short delay time, aimed at tooth restorations using a dual-cured resin cement.
Assuntos
Cimentos de Resina/química , Bis-Fenol A-Glicidil Metacrilato/química , Lâmpadas de Polimerização Dentária , Dureza , Humanos , Cura Luminosa de Adesivos Dentários/métodos , Teste de Materiais , Polietilenoglicóis/química , Polimerização , Ácidos Polimetacrílicos/química , Doses de Radiação , Autocura de Resinas Dentárias/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Fatores de TempoRESUMO
AIM: The aim of the present study was to evaluate the microleakage in class II cavities restored with dental composite by varying the thickness of two flowable composite resins and the restorative technique. METHODS: A total of 130 cavities were prepared on proximal surfaces of bovine teeth and randomly divided in 13 groups. Twelve experimental groups were performed using flowable composite resin as the liner, and they were divided according to the type of flowable composite resin (Filtek Z350 Flow-Z350F and SureFil SDR Flow-SUR), the thickness of the flowable composite (0.5, 1, or 2 mm), and the restorative technique (flowable composite applied at the cavosurface angle or amelodentinal junction) (n = 10). A control group was performed without using a flowable composite. Following restorative procedures and thermocycling, the samples were immersed in Methylene Blue for 2 h, and prepared for analysis in an absorbance spectrophotometer. All results were statistically analyzed (α = 0.05). RESULTS: There was no significant difference between the flowable composites (P > 0.05). The restorative techniques influenced microleakage and were flowable composite dependent (P ≤ 0.05). The lower thickness of the flowable composite provided less microleakage (P ≤ 0.05). CONCLUSION: The use a lower thickness of a flowable composite resin provided less microleakage, suggesting a better sealing tooth-restoration interface.
Assuntos
Resinas Compostas/química , Infiltração Dentária/classificação , Materiais Dentários/química , Restauração Dentária Permanente/métodos , Condicionamento Ácido do Dente/métodos , Animais , Bovinos , Corantes , Forramento da Cavidade Dentária/métodos , Preparo da Cavidade Dentária/classificação , Esmalte Dentário/ultraestrutura , Restauração Dentária Permanente/classificação , Dentina/ultraestrutura , Teste de Materiais , Azul de Metileno , Distribuição Aleatória , Espectrofotometria/instrumentação , Propriedades de Superfície , Temperatura , Fatores de Tempo , ViscosidadeRESUMO
AIM: To quantify the microleakage on restorations carried out with a two-step etch-and-rise adhesive system and nanofilled composite resin after thermal and mechanical loading cycling. METHODS: Ninety cavities were prepared on proximal surfaces of incisive teeth, and were randomly divided according to the photoactivation time (10, 20, or 30 s) and light-curing mode (Quartz Tungsten Halogen (QTH) lamps, 450 mW/cm(2); Light Emitting Diode (LED) second generation, 1100 mW/cm(2); or LED third generation, 700 mW/cm(2)) of an adhesive system (n = 10). Following restorative procedures and thermal and mechanical loading cycling, the samples were immersed in Methylene Blue for 2 h. The samples were ground, and the powder was prepared for analysis in an absorbance spectrophotometer. All results were statistically analyzed by anova and Tukey's test at the 5% level of significance. RESULTS: There were no significant statistical difference in microleakage between the light-curing mode (P = 0.1212) and light-curing time (P = 0.2043). CONCLUSION: Different curing modes and increasing the curing time were not factors that influenced the process of microleakage.
Assuntos
Resinas Compostas/química , Cimentos Dentários/química , Infiltração Dentária/classificação , Materiais Dentários/química , Restauração Dentária Permanente/métodos , Condicionamento Ácido do Dente/métodos , Animais , Bovinos , Corantes , Lâmpadas de Polimerização Dentária/classificação , Preparo da Cavidade Dentária/classificação , Restauração Dentária Permanente/classificação , Teste de Materiais , Azul de Metileno , Nanocompostos/química , Ácidos Fosfóricos/química , Polimerização , Distribuição Aleatória , Espectrofotometria/instrumentação , Estresse Mecânico , Temperatura , Fatores de Tempo , Água/químicaRESUMO
OBJECTIVES: This study evaluated the effectiveness of low- and high-concentration bleaching agents on enamel and deep dentin. STUDY DESIGN: Stained bovine incisors fragments were randomized placed into 10 groups (n=5), according to the sample thicknesses (2.0 mm or 3.5 mm) and bleaching agent: 10% carbamide peroxide (CP) (4 h a day/21 days); 6% hydrogen peroxide (HP) with calcium (1:30 h a day/21 days); HP 20% with calcium (50 min a day/3 sessions with a 7-day interval); HP 35% (3 x 15 min a day/3 sessions with a 7-day interval); HP 35% with calcium (40 min a day/3 sessions with a 7-day interval). The samples were stored in artificial saliva during the experiment. The color change was evaluated using a spectrophotometer at the initial analysis, after artificially staining with black tea and after each of the bleaching weeks, and data was expressed in CIE Lab System values. The L* coordinate data was submitted to analysis of variance and Tukey-Kramer test and the ?E values data was submitted for analysis of variance in a split-plot ANOVA and Tukey's test (?=0.05). RESULTS: None of the bleaching agents tested differed from the reflectance values on the enamel surface. For deep dentin HP 20% and HP 35%, both with calcium, showed the lowest reflectance values, which differed from CP 10%. CONCLUSION: It is concluded that high concentration hydrogen peroxide with calcium was less effective in deep dentin than 10% carbamide peroxide. Key words:Dental bleaching; hydrogen peroxide; carbamide peroxide; dental staining.