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1.
Am J Orthod Dentofacial Orthop ; 164(2): e51-e63, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37330727

RESUMO

INTRODUCTION: The dental industry is heavily committed to developing more esthetic solutions for orthodontic treatments. Invisalign is a system of transparent orthodontic aligners introduced as an alternative to conventional orthodontic fittings with brackets and metal wires. This study aimed to assess the chemical, physical, mechanical and morphologic changes in these polymeric aligners after exposure to the oral environment. METHODS: Twenty-four Invisalign orthodontic aligners were equally divided into 2 groups: an in vivo aged group in which patients used aligners for 14 days and the reference group, unexposed to the oral environment. Different experimental techniques were used to study the chemical structure, the color changes and translucency, the density and subsequent volume of the aligners, mechanical properties, surface roughness, morphology and elemental composition. The data were subjected to several statistical analyses. RESULTS: Clear orthodontic aligners exhibit chemical stability but undergo a statistically significant optical change in color and translucency. There was a gradual increase in the water absorption rate and the dimensional variation of the polymer, indicating a strong correlation among these factors. The mechanical properties of the polymer showed a statistically significant decrease in its elastic modulus and hardness. There was a slight tendency toward increased surface roughness of the material, but no statistical differences were found between reference and aged groups. The surface morphology of the used aligners demonstrates microcracks, distortions and biofilm formation. CONCLUSION: Intraoral aging adversely affected the physical, mechanical, and morphologic properties of the Invisalign appliance.


Assuntos
Aparelhos Ortodônticos , Polímeros , Aparelhos Ortodônticos/normas , Polímeros/química , Polímeros/normas , Boca/química , Fenômenos Químicos , Dureza , Cor , Fatores de Tempo , Humanos
2.
Sci Rep ; 10(1): 22312, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33339861

RESUMO

Plants may contain beneficial or potentially dangerous substances to humans. This study aimed to prepare and evaluate a new drug delivery system based on a glass-ionomer-Brazilian pepper extract composite, to check for its activity against pathogenic microorganisms of the oral cavity, along with its in vitro biocompatibility. The ethanolic Brazilian pepper extract (BPE), the glass-ionomer cement (GIC) and the composite GIC-BPE were characterized by scanning electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and thermal analysis. The BPE compounds were identified by UPLC-QTOF-MS/MS. The release profile of flavonoids and the mechanical properties of the GIC-BPE composite were assessed. The flavonoids were released through a linear mechanism governing the diffusion for the first 48 h, as evidenced by the Mt/M∞ relatively to [Formula: see text], at a diffusion coefficient of 1.406 × 10-6 cm2 s-1. The ATR-FTIR analysis indicated that a chemical bond between the GIC and BPE components may have occurred, but the compressive strength of GIC-BPE does not differ significantly from that of this glass-ionomer. The GIC-BPE sample revealed an ample bacterial activity at non-cytotoxic concentrations for the human fibroblast MRC-5 cells. These results suggest that the prepared composite may represent an alternative agent for endodontic treatment.


Assuntos
Anacardiaceae/química , Cimentos de Ionômeros de Vidro/síntese química , Boca/efeitos dos fármacos , Extratos Vegetais/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Brasil , Força Compressiva , Frutas/química , Cimentos de Ionômeros de Vidro/química , Cimentos de Ionômeros de Vidro/farmacologia , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Boca/química , Boca/microbiologia , Extratos Vegetais/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
3.
J Appl Oral Sci ; 27: e20180635, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31215600

RESUMO

OBJECTIVE: Acetaldehyde, associated with consumption of alcoholic beverages, is known to be a carcinogen and to be related to the tongue dorsum. The aim of this study was to investigate the relationship between acetaldehyde concentration in mouth air and bacterial characteristics on the tongue dorsum. METHODOLOGY: Thirty-nine healthy volunteers participated in the study. Acetaldehyde concentrations in mouth air were evaluated by a high-sensitivity semiconductor gas sensor. A 16S rRNA gene sequencing technique was used to compare microbiomes between two groups, focusing on the six samples with the highest acetaldehyde concentrations (HG) and the six samples with lowest acetaldehyde concentrations (LG). RESULTS: Acetaldehyde concentration increased in correlation with the increase in bacterial count (p=0.048). The number of species observed in the oral microbiome of the HG was higher than that in the oral microbiome of the LG (p=0.011). The relative abundances of Gemella sanguinis, Veillonella parvula and Neisseria flavescens in the oral microbiome of the HG were higher than those in the oral microbiome of the LG (p<0.05). CONCLUSION: Acetaldehyde concentration in mouth air was associated with bacterial count, diversity of microbiome, and relative abundance of G. sanguinis, V. parvula, and N. flavescens.


Assuntos
Acetaldeído/análise , Microbiota , Boca/química , Língua/microbiologia , Acetaldeído/metabolismo , Adulto , Consumo de Bebidas Alcoólicas/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Carga Bacteriana , Candida/isolamento & purificação , Estudos Transversais , Feminino , Humanos , Japão , Masculino , Boca/metabolismo , Boca/microbiologia , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/metabolismo , Valores de Referência , Fumar/metabolismo , Estatísticas não Paramétricas , Inquéritos e Questionários , Língua/metabolismo , Adulto Jovem
4.
J Infect Public Health ; 11(1): 126-129, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28684223

RESUMO

Initiatives to increase access to quality rapid HIV diagnostics have had relative success in the Caribbean in recent years, including use of oral rapid HIV testing. However, to date, there has not been any investigation into the performance or acceptability of oral fluids HIV testing in the region. In this cross-sectional study in The Bahamas, 252 persons of unknown serostatus were tested side-by-side with two oral rapid test brands, and the results were compared with the national fingerprick algorithm. In addition, an exit survey was administered to 234 study participants to assess user test preference. The most frequent survey response was to have no test preference (47.8%), but of those who expressed a test preference, most preferred oral (34.4%) versus fingerprick (17.8%) method. Both OraQuick and AWARE were 100% concordant with the gold standard. Therefore, our results show that oral fluids rapid testing is preferred over fingerprick testing by a subset of the potential target population and performs well in a population of undiagnosed persons attending screening clinic in The Bahamas.


Assuntos
Testes Diagnósticos de Rotina/métodos , Anticorpos Anti-HIV/análise , Infecções por HIV/diagnóstico , Boca/química , Aceitação pelo Paciente de Cuidados de Saúde , Adulto , Bahamas , Estudos Transversais , Feminino , Infecções por HIV/virologia , Humanos , Masculino , Inquéritos e Questionários , Adulto Jovem
5.
Braz Oral Res ; 31: e68, 2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-28832715

RESUMO

The objective of this study was to compare coating dimensions and surface characteristics of two different esthetic covered nickel-titanium orthodontic rectangular archwires, as-received from the manufacturer and after oral exposure. The study was designed for comparative purposes. Both archwires, as-received from the manufacturer, were observed using a stereomicroscope to measure coating thickness and inner metallic dimensions. The wires were also exposed to oral environment in 11 orthodontic active patients for 21 days. After removing the samples, stereomicroscopy images were captured, coating loss was measured and its percentage was calculated. Three segments of each wire (one as-received and two after oral exposure) were observed using scanning electron microscopy for a qualitative analysis of the labial surface of the wires. The Lilliefors test and independent t-test were applied to verify normality of data and statistical differences between wires, respectively. The significance level adopted was 0.05. The results showed that the differences between the wires while comparing inner height and thickness were statistically significant (p < 0.0001). In average, the most recently launched wire presented a coating thickness twice that of the control wire, which was also a statistically significant difference. The coating loss percentage was also statistically different (p = 0.0346) when the latest launched wire (13.27%) was compared to the control (29.63%). In conclusion, the coating of the most recent wire was thicker and more uniform, whereas the control had a thinner coating on the edges. After oral exposure, both tested wires presented coating loss, but the most recently launched wire exhibited better results.


Assuntos
Materiais Revestidos Biocompatíveis/química , Níquel/química , Desenho de Aparelho Ortodôntico , Fios Ortodônticos , Titânio/química , Estética Dentária , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Boca/química , Braquetes Ortodônticos , Valores de Referência , Propriedades de Superfície , Fatores de Tempo
6.
Braz. oral res. (Online) ; 31: e68, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-952108

RESUMO

Abstract The objective of this study was to compare coating dimensions and surface characteristics of two different esthetic covered nickel-titanium orthodontic rectangular archwires, as-received from the manufacturer and after oral exposure. The study was designed for comparative purposes. Both archwires, as-received from the manufacturer, were observed using a stereomicroscope to measure coating thickness and inner metallic dimensions. The wires were also exposed to oral environment in 11 orthodontic active patients for 21 days. After removing the samples, stereomicroscopy images were captured, coating loss was measured and its percentage was calculated. Three segments of each wire (one as-received and two after oral exposure) were observed using scanning electron microscopy for a qualitative analysis of the labial surface of the wires. The Lilliefors test and independent t-test were applied to verify normality of data and statistical differences between wires, respectively. The significance level adopted was 0.05. The results showed that the differences between the wires while comparing inner height and thickness were statistically significant (p < 0.0001). In average, the most recently launched wire presented a coating thickness twice that of the control wire, which was also a statistically significant difference. The coating loss percentage was also statistically different (p = 0.0346) when the latest launched wire (13.27%) was compared to the control (29.63%). In conclusion, the coating of the most recent wire was thicker and more uniform, whereas the control had a thinner coating on the edges. After oral exposure, both tested wires presented coating loss, but the most recently launched wire exhibited better results.


Assuntos
Humanos , Fios Ortodônticos , Titânio/química , Desenho de Aparelho Ortodôntico , Materiais Revestidos Biocompatíveis/química , Níquel/química , Valores de Referência , Propriedades de Superfície , Fatores de Tempo , Teste de Materiais , Microscopia Eletrônica de Varredura , Braquetes Ortodônticos , Estética Dentária , Boca/química
7.
Food Funct ; 7(3): 1483-91, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26883936

RESUMO

Citrus aurantium (bitter orange) extracts have been used in products for weight management and sports performance. These extracts contain large amounts of p-synephrine and much smaller amounts of p-octopamine. Both protoalkaloids exert lipolytic and glycogenolytic activities at similar concentrations. The biotransformation of p-synephrine and p-octopamine is not as well-known as those of other adrenergic amines. For this reason transformation of these amines was investigated in the isolated perfused liver. Special attention was devoted to the single pass extraction of each compound as well as to the kinetics of uptake. The assay of the amines in the outflowing perfusate was done by means of high performance liquid chromatography (HPLC). The single pass extraction of p-synephrine was higher than 90% at a portal concentration of 10 µM. It declined with the concentration, but was still around 30% at the concentration of 500 µM. At low concentrations (10-50 µM) the decreasing sequence of single pass extractions was p-synephrine > p-octopamine ≈ epinephrine > norepinephrine. Rates of uptake versus p-synephrine concentration resulted in a Michaelis-Menten type of relationship, with a KM value of 290.7 ± 32.1 µM and a Vmax of 0.762 ± 0.042 µmol min(-1) g(-1). The rates of uptake of p-octopamine did not present clear saturation and could be approximated by a linear relationship with a first order rate constant of 1.5 min(-1). The rapid hepatic transformation of p-synephrine and p-octopamine means that their concentration in the portal vein exceeds that in the systemic circulation during absorption. Their metabolic effects will, thus, be exerted predominantly in the liver.


Assuntos
Citrus/metabolismo , Fígado/metabolismo , Boca/metabolismo , Octopamina/metabolismo , Extratos Vegetais/metabolismo , Sinefrina/metabolismo , Animais , Biotransformação , Cinética , Fígado/química , Masculino , Boca/química , Octopamina/química , Extratos Vegetais/química , Ratos , Ratos Wistar , Sinefrina/química
8.
Pediatr Pulmonol ; 51(6): 596-600, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26584251

RESUMO

INTRODUCTION: Previous studies have suggested that full-term newborns delivered by elective cesarean section who develop transient tachypnea have low gastric microbubble counts. In the present study, microbubble concentrations in oral fluid samples were used to evaluate pulmonary maturity. OBJECTIVE: To evaluate lung maturity in full-term newborns delivered by elective caesarean section using the stable microbubble test in oral aspirates collected at birth. METHOD: The study involved newborns with gestational age >37 weeks delivered by elective cesarean section. Oral fluid samples were obtained in the delivery room immediately after birth, and gastric fluid was collected within the first hour of life. Samples were frozen and analyzed by two blinded researchers. RESULTS: The sample comprised 544 newborns. Twenty-two were diagnosed with transient tachypnea of the newborn by the assisting physician, and required admission to the Neonatal Intensive or Intermediate Care Unit. The median (interquartile range) of the number of microbubbles in the oral samples of these patients was 67.5 (45-150) microbubbles/mm(2) . The remaining 498 newborns without respiratory difficulties had a count of 350 (150-750) microbubbles/mm(2) -P < 0.001. Gastric fluid tests revealed a count of 150 (82.5-700) microbubbles/mm(2) for neonates with respiratory difficulties, and of 600 (216-1125) microbubbles/mm(2) -P < 0.05 for those without respiratory symptoms. CONCLUSION: The present results suggest that transient tachypnea of the newborn is associated with surfactant dysfunction. Pediatr Pulmonol. 2016;51:596-600. © 2015 Wiley Periodicals, Inc.


Assuntos
Líquidos Corporais/química , Cesárea , Pulmão/metabolismo , Pulmão/fisiologia , Microbolhas , Boca/química , Surfactantes Pulmonares/análise , Nascimento a Termo , Taquipneia Transitória do Recém-Nascido/fisiopatologia , Feminino , Suco Gástrico/química , Humanos , Recém-Nascido , Pulmão/fisiopatologia , Masculino , Gravidez , Surfactantes Pulmonares/metabolismo , Taquipneia Transitória do Recém-Nascido/metabolismo
9.
J Appl Oral Sci ; 23(1): 64-70, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25760268

RESUMO

OBJECTIVE: Acetaldehyde is the first metabolite of ethanol and is produced in the epithelium by mucosal ALDH, while higher levels are derived from microbial oxidation of ethanol by oral microflora such as Candida species. However, it is uncertain whether acetaldehyde concentration in human breath is related to oral condition or local production of acetaldehyde by oral microflora. The aim of this pilot study was to investigate the relationship between physiological acetaldehyde concentration and oral condition in healthy volunteers. MATERIAL AND METHODS: Sixty-five volunteers (51 males and 14 females, aged from 20 to 87 years old) participated in the present study. Acetaldehyde concentration in mouth air was measured using a portable monitor. Oral examination, detection of oral Candida species and assessment of alcohol sensitivity were performed. RESULTS: Acetaldehyde concentration [median (25%, 75%)] in mouth air was 170.7 (73.5, 306.3) ppb. Acetaldehyde concentration in participants with a tongue coating status score of 3 was significantly higher than in those with a score of 1 (p<0.017). After removing tongue coating, acetaldehyde concentration decreased significantly (p<0.05). Acetaldehyde concentration was not correlated with other clinical parameters, presence of Candida species, smoking status or alcohol sensitivity. CONCLUSION: Physiological acetaldehyde concentration in mouth air was associated with tongue coating volume.


Assuntos
Acetaldeído/análise , Boca/química , Língua/química , Acetaldeído/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Candida albicans/isolamento & purificação , Estudos Transversais , Etanol/metabolismo , Feminino , Humanos , Masculino , Microbiota , Pessoa de Meia-Idade , Boca/metabolismo , Boca/microbiologia , Respiração Bucal/metabolismo , Respiração Bucal/microbiologia , Valores de Referência , Fatores Sexuais , Estatísticas não Paramétricas , Inquéritos e Questionários , Fatores de Tempo , Língua/metabolismo , Língua/microbiologia , Adulto Jovem
10.
J. appl. oral sci ; 23(1): 64-70, Jan-Feb/2015. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: lil-741599

RESUMO

Objective Acetaldehyde is the first metabolite of ethanol and is produced in the epithelium by mucosal ALDH, while higher levels are derived from microbial oxidation of ethanol by oral microflora such as Candida species. However, it is uncertain whether acetaldehyde concentration in human breath is related to oral condition or local production of acetaldehyde by oral microflora. The aim of this pilot study was to investigate the relationship between physiological acetaldehyde concentration and oral condition in healthy volunteers. Material and Methods Sixty-five volunteers (51 males and 14 females, aged from 20 to 87 years old) participated in the present study. Acetaldehyde concentration in mouth air was measured using a portable monitor. Oral examination, detection of oral Candida species and assessment of alcohol sensitivity were performed. Results Acetaldehyde concentration [median (25%, 75%)] in mouth air was 170.7 (73.5, 306.3) ppb. Acetaldehyde concentration in participants with a tongue coating status score of 3 was significantly higher than in those with a score of 1 (p<0.017). After removing tongue coating, acetaldehyde concentration decreased significantly (p<0.05). Acetaldehyde concentration was not correlated with other clinical parameters, presence of Candida species, smoking status or alcohol sensitivity. Conclusion Physiological acetaldehyde concentration in mouth air was associated with tongue coating volume. .


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Acetaldeído/análise , Boca/química , Língua/química , Acetaldeído/metabolismo , Candida albicans/isolamento & purificação , Estudos Transversais , Etanol/metabolismo , Microbiota , Respiração Bucal/metabolismo , Respiração Bucal/microbiologia , Boca/metabolismo , Boca/microbiologia , Inquéritos e Questionários , Valores de Referência , Fatores Sexuais , Estatísticas não Paramétricas , Fatores de Tempo , Língua/metabolismo , Língua/microbiologia
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