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1.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 371-374, 2023.
Artigo em Chinês | WPRIM | ID: wpr-986016

RESUMO

Objective: To establish a inductively coupled plasma mass spectrometry method for the determination of trace cobalt and tungsten in human urine. Methods: The authors used 1% nitric acid solution as diluent in October-December 2021, the sample dilution factor and internal standard element were optimized by single factor rotation experiment, and the difference between the working curve and the standard curve was compared. Results: The method uses working curve to determine cobalt and tungsten in urine, the linear range of this method was 0.0~10.0 μg/L, the correlation coefficient was 0.999 9, the detection limits respectively were 0.005 μg/L (cobalt) and 0.09 μg/L (tungsten), the recoveries of samples respectively were 87.0%~100.2% (cobalt) and 89.4%~104.8% (tungsten), the relative standard deviations respectively were 0.4%~4.4% (cobalt) and 0.6%~3.8% (tungsten) . Conclusion: A simple and rapid method for determination of cobalt and tungsten in urine has been established. This method has the advantages of simple operation, high sensitivity, low detection limit and good stability. It is suitable for determination of cobalt and tungsten in urine of all kinds of people.


Assuntos
Humanos , Cobalto/análise , Tungstênio/análise , Análise Espectral , Ácido Nítrico , Espectrometria de Massas
2.
Artigo em Inglês | LILACS, BBO | ID: biblio-1101284

RESUMO

Abstract Objective: To assess the cytotoxicity, surface morphology, elemental compositions and chemical characterization of two commonly used luting cement. Material and Methods: The two luting types of cement used were Elite Cement® and Hy-Bond Resiglass®. Freshly mixed (n=6) and set form (n=6) of each cement was placed in medium to obtain extracts. The extract from each sample was exposed to L929 mouse fibroblasts (1x104cells/well). Alamar Blue Assay assessed cell viability. Surface morphology and elemental composition were evaluated using scanning electron microscopy and energy dispersive spectroscopy. The chemical characterization was performed by Fourier Transform Infrared Spectroscopy. One-way ANOVA and post-hoc Tukey analysis were conducted to assess results. Results: Hy-Bond Resiglass® was the more cytotoxic of the two types of cement in both freshly mixed (68.10 +5.16; p<0.05) and set state (87.58 +4.86; p<0.05), compared to Elite Cement® both freshly mixed (77.01 +5.45; p<0.05) and set state (89.39 +5.66; p<0.05). Scanning electron microscopy revealed a more irregular and porous structure in Hy-Bond Resiglass® compared to Elite Cement®. Similarly, intense peaks of aluminium, tungsten and fluorine were observed in energy dispersive spectroscopy in Hy-Bond Resiglass. Conclusion: All these three elements (aluminium, tungsten and fluorine) have cytotoxic potential. The Fourier transform infrared spectroscopy revealed the presence of hydroxyethyl methacrylate in Hy-Bond Resiglass®, which has a cytotoxic potential.


Assuntos
Animais , Camundongos , Ratos , Cimento de Fosfato de Zinco , Técnicas In Vitro/métodos , Cimentos Dentários , Fibroblastos , Paquistão , Ratos , Análise Espectral , Tungstênio , Microscopia Eletrônica de Varredura , Análise de Variância , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Journal of Korean Medical Science ; : e24-2019.
Artigo em Inglês | WPRIM | ID: wpr-719566

RESUMO

BACKGROUND: Recently, carbon fibers have been utilized to develop a depth-type microelectrode array for chronic neural recording. Since the diameter of carbon fibers is smaller than the conventional electrodes made of metal wires or microfabricated silicon, the carbon fiber electrodes showed an improved capability for chronic neural recording with less tissue damages. However, the carbon fiber based microelectrodes have a limitation of short insertion depth due to a low stiffness. METHODS: We proposed a carbon fiber based microelectrode array embedded with a mechanical support structure to facilitate the penetration into the deeper brain. The support is made of biodegradable silk fibroin to reduce the reactive tissue responses. The 4-channel carbon fiber based microelectrode arrays were fabricated and accessed in terms of electrochemical impedance, recording capability for 1-month implantation in rat hippocampi. The electrodes with tungsten supports were fabricated and tested as a control group. Immunohistochemical analysis was performed to identify the reactive glial responses. RESULTS: The carbon fiber based electrode arrays with silk supports showed about 2-fold impedance increase 2 weeks after implantation while the number of active electrodes decreased simultaneously. However, after 1 month, the electrode impedance decreased back to its initial value and the percentage of active electrodes also increased above 70%. Immunohistochemical staining clearly showed that the electrodes with silk supports induced less reactive glial responses than that with tungsten supports. CONCLUSION: The proposed carbon fiber based microelectrode array is expected to be used for long-term in vivo neural recording from deep brain regions with the minimized reactive tissue response.


Assuntos
Animais , Ratos , Encéfalo , Carbono , Impedância Elétrica , Eletrodos , Fibroínas , Microeletrodos , Silício , Seda , Tungstênio
4.
West Afr. j. radiol ; 26(2): 90-93, 2019.
Artigo em Inglês | AIM | ID: biblio-1273552

RESUMO

Background: Radiation dose depends on the total workload (Wtot) which is affected by the number of patients, tube potential, and tube current. Despite the increment in patients visiting the X-ray units under study and X-ray tube revolutions, changes have not been made in the shielding material to suit the current situation. Aims: This study aims to evaluate the thickness of X-ray shielding barriers in two tertiary hospitals in Kano Metropolis using XRAYBAR software. Materials and Methods: This was a prospective, cross-sectional study and was undertaken from March 2017 to October 2017. A purposive sampling technique was employed to select two hospitals out of five. The two were named A and B, respectively. The minimum required thickness in each barrier was determined by XRAYBAR software. Results: The Wtot (workload) for room I, II and III was found to be 199.9, 146, and 149.1 mA-min per week. The shielding barrier thickness required to reduce the unshielded radiation dose to the design dose limit for wall 1, 2, 3, 4, and operating console of the Room I was found to be 17.5, 5.5, 0.2, 0.00, 3.3 cm, that of wall 1, 2, 3, and 4 of room II was found to be 9.1, 3.4, 0.02, 2.3 cm, while for the wall 1, 2, 3, 4, and operating console of room III was found to be 12.3, 4.8, 3.8, 3.2, and 26.5 cm, respectively. Conclusion: The calculated shielding barrier thickness from XRAYBARR code when compared to the design barrier thickness was found to be adequate


Assuntos
Nigéria , Doses de Radiação , Proteção Radiológica/instrumentação , Tungstênio , Raios X
5.
Annals of Pediatric Endocrinology & Metabolism ; : 166-167, 2018.
Artigo em Inglês | WPRIM | ID: wpr-717064

RESUMO

No abstract available.


Assuntos
Falência Renal Crônica , Tungstênio , Síndrome de Wolfram
6.
The Korean Journal of Orthodontics ; : 245-252, 2018.
Artigo em Inglês | WPRIM | ID: wpr-716087

RESUMO

OBJECTIVE: We aimed to perform in-vitro evaluation to compare 1) shear bond strength (SBS), adhesive remnant index (ARI), and color change between self-etched and acid-etched primers; 2) the SBS, ARI and color change between direct and indirect bonding; and 3) the enamel roughness (ER) between 12-blade bur and aluminum oxide polisher debonding methods. METHODS: Seventy bovine incisors were distributed in seven groups: control (no bonding), direct (DTBX), and 5 indirect bonding (ITBX, IZ350, ISONDHI, ISEP, and ITBXp). Transbond XT Primer was used in the DTBX, ITBX, and ITBXp groups, flow resin Z350 in the IZ350 group, Sondhi in the ISONDHI group, and SEP primer in the ISEP group. SBS, ARI, and ER were evaluated. The adhesive remnant was removed using a low-speed tungsten bur in all groups except the ITBXp, in which an aluminum oxide polisher was used. After coffee staining, color evaluations were performed using a spectrophotometer immediately after staining and prior to bonding. RESULTS: ISONDHI and ISEP showed significantly lower SBS (p < 0.01). DTBX had a greater number of teeth with all the adhesive on the enamel (70%), compared with the indirect bonding groups (0–30%). The ER in the ITBX and ITBXp groups was found to be greater because of both clean-up techniques used. CONCLUSIONS: Direct and indirect bonding have similar results and all the primers used show satisfactory adhesion strength. Use of burs and polishers increases the ER, but polishers ensure greater integrity of the initial roughness. Resin tags do not change the color of the teeth.


Assuntos
Adesivos , Óxido de Alumínio , Café , Esmalte Dentário , Incisivo , Resistência ao Cisalhamento , Dente , Tungstênio
7.
The Journal of Advanced Prosthodontics ; : 110-117, 2017.
Artigo em Inglês | WPRIM | ID: wpr-179522

RESUMO

PURPOSE: This laboratory study assessed the effect of different dentin cleaning procedures on shear bond strength of resin cements for recementing prosthesis. MATERIALS AND METHODS: 4 × 4 flat surface was prepared on the labial surface of 52 maxillary central incisors. Metal frames (4 × 4 × 1.5 mm) were cast with nickel-chromium alloy. All specimens were randomly divided into 2 groups to be cemented with either Panavia F2.0 (P) or RelyX Ultimate (U) cement. The initial shear bond strength was recorded by Universal Testing Machine at a crosshead speed of 0.5 mm/min. Debonded specimens were randomly allocated into 2 subgroups (n = 13) according to the dentin cleaning procedures for recementation. The residual cement on bonded dentin surfaces was eliminated with either pumice slurry (p) or tungsten carbide bur (c). The restorations were rebonded with the same cement and were subjected to shear test. Data failed the normality test (P < .05), thus were analyzed with Mann Whitney U-test, Wilcoxon signed rank test, and two-way ANOVA after logarithmic transformation (α = .05). RESULTS: The initial shear bond strength of group P was significantly higher than group U (P = .001). Pc and Uc groups presented higher bond strength after recementation compared to the initial bond strength. However, it was significant only in Pc group (P = .034). CONCLUSION: The specimens recemented with Panavia F2.0 provided higher bond strength than RelyX Ultimate cement. Moreover, a tungsten carbide bur was a more efficient method in removing the residual resin cement and increased the bond strength of Panavia F2.0 cement after recementation.


Assuntos
Ligas , Dentina , Incisivo , Métodos , Próteses e Implantes , Cimentos de Resina , Tungstênio
8.
J. bras. pneumol ; 42(6): 447-452, Nov.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-841240

RESUMO

ABSTRACT Objective: To describe diagnostic and treatment aspects of hard metal lung disease (HMLD) and to review the current literature on the topic. Methods: This was a retrospective study based on the medical records of patients treated at the Occupational Respiratory Diseases Clinic of the Instituto do Coração, in the city of São Paulo, Brazil, between 2010 and 2013. Results: Of 320 patients treated during the study period, 5 (1.56%) were diagnosed with HMLD. All of those 5 patients were male (mean age, 42.0 ± 13.6 years; mean duration of exposure to hard metals, 11.4 ± 8.0 years). Occupational histories were taken, after which the patients underwent clinical evaluation, chest HRCT, pulmonary function tests, bronchoscopy, BAL, and lung biopsy. Restrictive lung disease was found in all subjects. The most common chest HRCT finding was ground glass opacities (in 80%). In 4 patients, BALF revealed multinucleated giant cells. In 3 patients, lung biopsy revealed giant cell interstitial pneumonia. One patient was diagnosed with desquamative interstitial pneumonia associated with cellular bronchiolitis, and another was diagnosed with a hypersensitivity pneumonitis pattern. All patients were withdrawn from exposure and treated with corticosteroid. Clinical improvement occurred in 2 patients, whereas the disease progressed in 3. Conclusions: Although HMLD is a rare entity, it should always be included in the differential diagnosis of respiratory dysfunction in workers with a high occupational risk of exposure to hard metal particles. A relevant history (clinical and occupational) accompanied by chest HRCT and BAL findings suggestive of the disease might be sufficient for the diagnosis.


RESUMO Objetivo: Descrever aspectos relacionados ao diagnóstico e tratamento de pacientes com doença pulmonar por metal duro (DPMD) e realizar uma revisão da literatura. Métodos: Estudo retrospectivo dos prontuários médicos de pacientes atendidos no Serviço de Doenças Respiratórias Ocupacionais do Instituto do Coração, localizado na cidade de São Paulo, entre 2010 e 2013. Resultados: Entre 320 pacientes atendidos no período do estudo, 5 (1,56%) foram diagnosticados com DPMD. Todos os pacientes eram do sexo masculino, com média de idade de 42,0 ± 13,6 anos e média de tempo de exposição a metal duro de 11,4 ± 8,0 anos. Os pacientes foram submetidos a avaliação clinica, história ocupacional, TCAR de tórax, prova de função pulmonar, broncoscopia com LBA e biópsia pulmonar. Todos apresentaram distúrbio ventilatório restritivo. O achado de imagem à TCAR de tórax mais frequente foi de opacidades em vidro fosco (em 80%). Em 4 pacientes, o LBA revelou presença de células gigantes multinucleadas. Em 3, foi diagnosticada pneumonia intersticial por células gigantes na biópsia pulmonar. Houve o diagnóstico de pneumonia intersticial descamativa associada à bronquiolite celular em 1 paciente e de pneumonite de hipersensibilidade em 1. Todos foram afastados da exposição e tratados com corticoide. Houve melhora em 2 pacientes e progressão da doença em 3. Conclusões: Apesar de ser uma entidade rara, a DPMD deve ser sempre considerada em trabalhadores com risco ocupacional elevado de exposição a metais duros. A história clínica e ocupacional associada a achados em TCAR de tórax e LBA sugestivos da doença podem ser suficientes para o diagnóstico.


Assuntos
Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Ligas/efeitos adversos , Ligas/toxicidade , Cobalto/efeitos adversos , Cobalto/toxicidade , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Profissionais/diagnóstico , Exposição Ocupacional/efeitos adversos , Tungstênio/efeitos adversos , Tungstênio/toxicidade , Corticosteroides/uso terapêutico , Biópsia , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/patologia , Pulmão/diagnóstico por imagem , Pulmão/patologia , Doenças Profissionais/tratamento farmacológico , Doenças Profissionais/patologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
9.
Rev. biol. trop ; 64(3): 1077-1089, jul.-sep. 2016. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-958197

RESUMO

Abstract:Coral reefs are under intense conditions of stress caused by the anthropogenic activities in coastal areas and the increase of human population. Water effluents from urban and industrial areas carry large amounts of sediments and pollutants affecting corals populations, inducing bioerosion, increasing diseases and promoting the development of algae that compete for space with corals. In the Veracruz Reef System National Park (VRSNP) coral reefs are strongly affected by human activities carried out in the area. Gallega and Galleguilla reefs are among the most affected by wastewater discharges from the industrial (petrochemical and metallurgical) and urban areas in their vicinity. To assess the potential impact of this contamination on corals in the VRSNP, a chemical composition and morphology study of 76 Pseudodiploria colonies collected in reefs Gallega, Galleguilla, Isla Verde and Isla de Enmedio, was performed. Fragments of ~10 cm2 were collected and boric acid at 0.5 % was used to remove tissue from the skeleton; once clean, the morphology of each sample was determined with a scanning electron microscope (SEM). Subsequently, to test the chemical composition, an energy dispersion spectroscopy of X-ray chemical microanalysis (EDSX) was performed in the SEM. We found that corals from Gallega and Galleguilla reefs, located closer to human populations, presented high levels of tungsten and the skeleton exhibited multiple perforations. In contrast, corals from the farthest offshore reefs (Isla Verde and Isla de Enmedio) exhibited lower levels of tungsten and fewer perforations in their skeleton. These results demonstrated that anthropogenic activities in the NPVRS are affecting corals skeleton, highly damaging and promoting their bioerosion. The presence of traces of tungsten in the skeleton of corals is an evidence of the damage that waste discharges are causing to coral reefs. Discharges of large amounts of contaminants promoted the growth of harmful species that grow and develop into the corals skeleton, causing its bioerosion, and making them susceptible to disease and physical damage. This study is the first evidence of the effects of contamination on these species; therefore, further studies are necessary to determine the impact of pollution on their biology and survival. Rev. Biol. Trop. 64 (3): 1077-1089. Epub 2016 September 01.


ResumenLos arrecifes de coral se encuentran bajo condiciones intensas de estrés causado por las actividades antropogénicas y el incremento de las poblaciones humanas en las zonas costeras. Las descargas de aguas de origen urbano e industrial transportan sedimentos y contaminantes que afectan a las poblaciones de corales, induciendo la bioerosion, el aumento de enfermedades en los corales y promueven el desarrollo de algas que compiten por espacio con los corales. En el Parque Nacional Sistema Arrecifal Veracruzano (NPVRS) los arrecifes de coral son afectados fuertemente por las actividades humanas que se llevan a cabo en la zona. Los arrecifes Gallega y Galleguilla son de los más afectados por las descargas de aguas residuales provenientes de la industria (petroquímica y metalúrgica) y de áreas urbanas que desembocan sus aguas en las proximidades de los arrecifes. Para evaluar el posible impacto de las descargas de aguas en los corales del NPVRS, se realizó un estudio de la composición química y morfología de 76 colonias de Pseudodiploria en los arrecifes Gallega, Galleguilla, Isla Verde e Isla de Enmedio. Se recolectaron fragmentos de ~10 cm2, el tejido del esqueleto fue removido utilizando ácido bórico al 0.5 %. Una vez limpia la muestra, la morfología fue analizada con un microscopio electrónico de barrido (SEM), posteriormente, para analizar la composición química de las muestras, realizamos una espectroscopia de dispersión de energía o micro-análisis químico de rayos X (EDSX) en el SEM. Encontramos que los corales de los arrecifes Gallega y Galleguilla que se encuentran ubicados cerca de poblaciones humanas, presentan altos niveles de tungsteno y el esqueleto exhibe múltiples agujeros. En contraste, los corales de los arrecifes más lejanos (Isla Verde e Isla de En medio) mostraron niveles más bajos de tungsteno y un menor número de agujeros en su esqueleto. Nuestros resultados demuestran que las actividades antropogénicas en el NPVRS, están afectando el esqueleto de los corales y promueven la bioerosión. Las descargas de grandes cantidades de contaminantes hacia las zonas costeras, promueven el crecimiento de especies dañinas que crecen y se desarrollan dentro del esqueleto de los corales, causando bioerosión del esqueleto, haciéndolos susceptibles a enfermedades y daños físicos. Debido a que este estudio es la primera evidencia de los efectos de la contaminación sobre esta especie de corales, son necesarios más estudios para determinar el impacto de la contaminación sobre su biología y la supervivencia de los corales.


Assuntos
Animais , Tungstênio/análise , Poluentes Químicos da Água/química , Antozoários/química , Recifes de Corais , Valores de Referência , Água do Mar/química , Espectrometria por Raios X , Microscopia Eletrônica de Varredura , Monitoramento Ambiental , Antozoários/anatomia & histologia , México
10.
Rev. méd. Chile ; 144(7): 837-843, jul. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-793996

RESUMO

Background: The effectiveness against radiation of tungsten bismuth caps, used in interventional cardiology is not well known. Aim: To determine the degree of radiation protection conferred by these caps in real work conditions. Material and Methods: We compared the gross electric charges received at brain lobe levels by three occupationally exposed professionals who participated in 22 consecutive procedures, inside and outside of the tungsten bismuth cap. Results: The median electric charges outside and inside the cap were 3.71 (range 1.46-5.62) and 2.2 (range 1.29-3.93) nC, which correspond to a 40% radiation attenuation. However, the protection was heterogeneous. Conclusions: Tungsten bismuth caps provide an adequate attenuation, but its degree is heterogeneous.


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Roupa de Proteção , Lesões por Radiação/prevenção & controle , Proteção Radiológica/instrumentação , Tungstênio , Bismuto , Radiografia Intervencionista , Exposição Ocupacional/prevenção & controle , Doses de Radiação , Exposição Ocupacional/estatística & dados numéricos , Exposição à Radiação/prevenção & controle
11.
Bauru; s.n; 2016. 94 p. ilus, tab.
Tese em Português | LILACS, BBO | ID: biblio-881415

RESUMO

A atresia maxilar é um quadro de desarranjo de desenvolvimento do arco dentário presente em diversos tipos de má oclusão, desde as alterações transversais mais simples e puras até as formas mais graves, contemplando as divergências verticais e sagitais. O diagnóstico desta atresia, muitas vezes, é simplificado na presença ou não de mordida cruzada posterior, sendo ela unilateral ou bilateral. No entanto, faz-se necessário uma avaliação mais criteriosa que compreenda não só a própria alteração de forma do arco dentário, mas também as modificações oclusais subsequentes, como relação sagital de classe II ou III de Angle ou as discrepâncias verticais. Uma das possíveis formas de tratamento ortodôntico está ligada as expansões rápidas da maxila, método de incrementos ósseos por meio de forças ortopédicas, quando o indivíduo ainda apresenta potencial de crescimento craniofacial, ou seja, crianças e adolescentes. Já na vida adulta, esta possibilidade de ganhos ortopédicos não mais está presente e a opção não cirúrgica é o tratamento ortodôntico compensatório, por meio de expansão dentoalveolar do arco maxilar. O objetivo deste trabalho foi descrever os resultados de expansão dentoalveolar, obtidos utilizando-se o arco auxiliar de expansão em TMA (tungstênio, molibdênio e alloy), a partir de medidas lineares e angulares obtidas, bem como a integridade da cortical óssea vestibular desta área. Foi realizado um estudo retrospectivo de análise de tomografias computadorizadas, contidas na documentação ortodôntica de 13 pacientes tratados em uma clínica particular, realizadas antes e após a realização desta mecânica de expansão dentoalveolar. Para esta expansão, estes pacientes foram submetidos à instalação de um sobre-arco utilizado por vestibular como um arco auxiliar, sendo justaposto e unido ao fio de nivelamento principal (0,017x0,025 Termoativado) em cinco pontos, sendo 2 pontos nas entradas do tubo dos primeiros molares, 2 pontos entre os pré-molares e 1 ponto entre os incisivos centrais, por meio de fio de amarrilho 0,010 aço. Os resultados apresentaram ganhos estatisticamente significantes para aumento da distância das cúspides ao plano vertical mediano de todos os dentes medidos, bem como aumento da inclinação vestibular destes. A cortical óssea demonstrou adaptação, tendo deslocamento na mesma direção do movimento dentário, porém em menor quantidade. O aumento transversal das distâncias inter-dentárias também apresentou aumentos significativos e condizentes com a literatura. Desta forma, o arco auxiliar de expansão demonstrou-se eficiente para expansão dentoalveolar no paciente adulto, por meio de aumento da inclinação vestibular, com deslocamento dentário maior que o movimento de crista óssea, apresentado ganhos transversais significantes.(AU)


The Maxillary constriction is a developmental disorder present in various types of malocclusion, from the most simple and pure transverse changes to the most severe forms, causing vertical and sagittal problems. This malocclusion diagnosis is often simplified in the presence or not of posterior crossbite, which can be uni or bilateral. However, a complete evaluation must include not only the dental arch form changes, but also the subsequent occlusal modifications, such as sagittal relationships of Class II or III malocclusions and vertical discrepancies. Maxillary constriction treatment can be performed by rapid maxillary expansion, using orthopedic forces when there is still craniofacial growth. In adults, the possibility of orthopedic changes is no longer present and the non-surgical option is compensatory orthodontic treatment with dentoalveolar expansion, when the disorder magnitude allows. The objective of this study was to evaluate the effects of dentoalveolar expansion, obtained with a TMA (tungsten and molybdenum alloy) auxiliary expansion archwire, by means of linear and angular measurements, and the integrity of the buccal cortical bone in the posterior area. A retrospective analysis of CT scans, of orthodontic records of 13 patients treated at a private clinic, performed immediately before and after the auxiliary expansion archwire, was used. For the expansion, the patients underwent installation of a secondary arch combined with the primary archwire (0.017x0.025-inch heatactivated Ni-Ti), ligated in five points. Two points in the first molar tube entries, 2 points between the premolars and 1 point between the central incisors, with a 0.010- inch steel ligature wire. The results showed statistically significant transverse increase and buccal inclination for all teeth. The cortical bone showed adaptability and displacement in the same direction of tooth movement, but in smaller amounts. Thus, the auxiliary expansion arch wire proved to be effective to correct dentoalveolar constriction in adult patients, by increasing the buccal dental inclination with larger displacements than the bone crest adaptation and with significant transverse gains.(AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Processo Alveolar/anatomia & histologia , Má Oclusão/terapia , Aparelhos Ortodônticos , Técnica de Expansão Palatina/instrumentação , Ligas/uso terapêutico , Molibdênio/uso terapêutico , Odontometria , Desenho de Aparelho Ortodôntico , Valores de Referência , Estudos Retrospectivos , Estatísticas não Paramétricas , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Tungstênio/uso terapêutico
12.
JDB-Journal of Dental Biomaterials. 2016; 3 (1): 192-198
em Inglês | IMEMR | ID: emr-176267

RESUMO

Statement of Problem: One of the factors affecting the degree of polymerization of light-cured composites is the type of light-curing unit used. In addition, physicomechanical properties of the composite resins depend on the degree of conversion and polymerization


Objectives: Since the type of initiator in new composite resins is not explained by manufacturers, this study is an attempt to compare the depth of hardening, with two LED and QTH light-curing units


Materials and Methods: Fifteen samples prepared from Gradia Direct and Filtek Z250, both of which being universal, were cured with QTH [Astralis 7] and LED [Bluephase C8] light-curing units. All the samples were molded in polyester resin and cut from the middle by a disk. The hardness of the cut area was evaluated at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5 and 4-mm depth intervals and also at the same interval as the width of the sample, with Vickers hardness machine, while the samples were placed in a darkroom. Data were statistically analyzed using one-way ANOVA, two-way ANOVA, t-test and post Hoc Tukey's tests in SPSS, version 16


Results: Filtek Z250 was harder than Gradia Direct at all the depth with both light-curing units. The hardness of Filtek Z250 sample cured with Astralis 7 was higher than that cured with LED, but with Gradia Direct the LED unit resulted in higher hardness. Curing depth was not significantly different between the groups [p = 0.109]


Conclusions: Vickers hardness number for both composites used in this study is in an acceptable range for clinical implications. The composites' composition is important to be considered for selection of light unit. Based on the findings of the present study, LED did not present more curing depth compared with QTH


Assuntos
Dureza , Luz , Quartzo , Lâmpadas de Polimerização Dentária , Tungstênio , Halogênios
13.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 45-48, 2015.
Artigo em Chinês | WPRIM | ID: wpr-326087

RESUMO

<p><b>OBJECTIVE</b>We sought to master the clinical characteristics and prognosis of hard mental lung disease, improving this disease's diagnosis and treatment quality.</p><p><b>METHODS</b>We recruited two suspected patients with hard mental lung disease and collected their occupational history, examination results of occupational health, and past medical records. By virtue of laboratory tests, high Kv chest radiography, CT and HRCT of chest, fiberoptic bronchoscopy and ECG examination, diagnostic report was synthesized respectively by respiratory physicians and pathologist from three different agencies. Then the report was submitted to diagnosis organizations of occupational disease, and diagnostic conclusion of occupational disease was drawn after discussion by at least three diagnosticians of occupational disease.</p><p><b>RESULTS</b>We found that both of the two suspected patients were exposed to dusts of hard metal, and length of exposure service ranged from 8 to 9 years. Clinical manifestations were dominated by dry cough, wheezing after activities, and pathological manifestation was characteristic giant cell interstitial pneumonia. The prognosis and outcome of the disease were different.</p><p><b>CONCLUSION</b>According to exact occupational exposure history, clinical manifestations, combined with the results of high Kv chest radiography, CT of chest and pathological manifestation, it can be diagnosed with hard mental lung disease.</p>


Assuntos
Humanos , Ligas , Broncoscopia , Cobalto , Poeira , Pulmão , Patologia , Pneumopatias , Diagnóstico , Doenças Profissionais , Diagnóstico , Exposição Ocupacional , Tungstênio
14.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 387-391, 2015.
Artigo em Chinês | WPRIM | ID: wpr-350593

RESUMO

<p><b>OBJECTIVE</b>To analyze the clinical features and investigate the clinical diagnostic methods of hard metal lung disease (HMLD), then provide reference for the diagnostic criteria of occupational HMLD.</p><p><b>METHODS</b>Retrieved the open published case reports associated with HMLD from January, 2000 to June, 2014. Regarding the ages, sex, types and years of work, clinical features and laboratory results for analyzing.</p><p><b>RESULTS</b>Collected 21 clinical cases of HMLD belonged to 6 internal reports and 15 oversea reports. Among them 15 male and 6 female, ages were from 22 to 58, length of service between 1 year and 43 years. Clinical presentations included cough (20 cases), dyspnea on progressive (10 cases), and pulmonary function testing showed a restrictive abnormality. The imaging features presented as bilateral areas of ground-glass attenuation, diffuse small nodules, extensive reticular opacities and traction bronchiectasis. The finding of giant cell interstitial pneumonia (GIP) was almost pathognomonic for hard metal pneumoconiosis. The main pathological findings contained a different levels of lymphocyte, acidophilic cell infiltration, hyperplasia of fibrous tissue and numerous large multinucleated histiocytes which ingested inflammatory cells were admixed with macrophages. 16 cases of the 21 reports showed GIP.</p><p><b>CONCLUSIONS</b>Clinical presentations include cough and dyspnea on progressive, and pulmonary function testing show a restrictive abnormality. The imaging features present as bilateral areas of ground-glass attenuation, areas of consolidation, diffuse small nodules, extensive reticular opacities and traction bronchiectasis. The prime pathological findings contain interstitial pneumonia with intra-alveolar macrophages and a large amount of multinucleated histiocytes.</p>


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Ligas , Cobalto , Pulmão , Doenças Pulmonares Intersticiais , Patologia , Macrófagos Alveolares , Doenças Profissionais , Patologia , Pneumoconiose , Patologia , Tungstênio
15.
The Journal of Advanced Prosthodontics ; : 249-256, 2015.
Artigo em Inglês | WPRIM | ID: wpr-71463

RESUMO

PURPOSE: The aim of this study was to evaluate the effects of atmospheric plasma (APL) versus conventional surface treatments on the adhesion of self-adhesive resin cement to Ti-6Al-4V alloy. MATERIALS AND METHODS: Sixty plates of machined titanium (Ti) discs were divided into five groups (n=12): 1) Untreated (CNT); 2) Sandblasted (SAB); 3) Tribochemically treated (ROC); 4) Tungsten CarbideBur (TCB); 5) APL treated (APL). SEM analysis and surface roughness (Ra) measurements were performed. Self-adhesive resin cement was bonded to the Ti surfaces and shear bond strength (SBS) tests, Ra and failure mode examinations were carried out. Data were analyzed by one-way analysis of variance and chi-squared test. RESULTS: The lowest SBS value was obtained with CNT and was significantly different from all other groups except for APL. The ROC showed the highest SBS and Ra values of all the groups. CONCLUSION: It was concluded that the effect of APL on SBS and Ra was not sufficient and it may not be a potential for promoting adhesion to titanium.


Assuntos
Ligas , Gases em Plasma , Plasma , Cimentos de Resina , Titânio , Tungstênio
16.
Braz. dent. j ; 25(6): 479-484, Nov-Dec/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-732264

RESUMO

The present study analyzed the action of sodium trimetaphosphate (TMP) and/or fluoride on hydroxyapatite. Hydroxyapatite powder was suspended in different solutions: deionized water, 500 µg F/mL, 1,100 µg F/mL, 1%TMP, 3%TMP, 500 µg F/mL plus 1%TMP and 500 µg F/mL plus 3%TMP. The pH value of the solutions was reduced to 4.0 and after 30 min, raised to 7.0 (three times). After pH-cycling, the samples were analyzed by X-ray diffraction and infrared spectroscopy. The concentrations of calcium fluoride, fluoride, calcium and phosphorus were also determined. Adding 1% or 3% TMP to the solution containing 500 µg F/mL produced a higher quantity of calcium fluoride compared to samples prepared in a 1,100 µg F/mL solution. Regarding the calcium concentration, samples prepared in solutions of 1,100 µg F/mL and 500 µg F/mL plus TMP were statistically similar and showed higher values. Using solutions of 1,100 µg F/mL and 500 µg F/mL plus TMP resulted in a calcium/phosphorus ratio close to that of hydroxyapatite. It is concluded that the association of TMP and fluoride favored the precipitation of a more stable hydroxyapatite.


O presente estudo avaliou a ação do trimetafosfato de sódio (TMP) e/ou fluoreto sobre a hidroxiapatita. Pó de hidroxiapatita foi suspenso em diferentes soluções: água deionizada, 500 µg F/mL, 1100 µg F/mL, 1%TMP, 3%TMP, 500 µg F/mL adicionado a 1%TMP e 500 µg F/mL associado a 3%TMP. O pH das soluções foi reduzido para 4,0 e depois de 30 min, elevado para 7,0 (três vezes). Depois do processo de ciclagem de pH, as amostras foram analisadas por difração de raios-X e espectroscopia por infravermelho. As concentrações de fluoreto de cálcio, fluoreto, cálcio e fósforo também foram determinadas. A adição de 1% ou 3% TMP na solução contendo 500 µg F/mL produziu uma maior quantidade de fluoreto de cálcio comparado às amostras tratadas com uma solução de 1100 µg F/mL. A respeito da concentração de cálcio, amostras tratadas com soluções de 1100 µg F/mL e 500 µg F/mL adicionado ao TMP foram estatisticamente similares e mostraram maiores valores. Soluções de 1100 µg F/mL e 500 µg F/mL adicionado ao TMP resultaram em uma proporção molar Ca/P mais próxima à da hidroxiapatita. Conclui-se que a associação de TMP e F favoreceu a precipitação de uma hidroxiapatita mais estável.


Assuntos
Animais , Camundongos , Infecções Bacterianas/microbiologia , Endotoxinas/toxicidade , Escherichia coli/patogenicidade , Mucosa Intestinal/microbiologia , Compostos de Tungstênio , Alopurinol/farmacologia , Gentamicinas/farmacologia , Íleo/microbiologia , Íleo/patologia , Polimixina B/farmacologia , Compostos de Quinolínio/farmacologia , Tungstênio/farmacologia , Xantina Oxidase/antagonistas & inibidores
18.
Restorative Dentistry & Endodontics ; : 155-163, 2014.
Artigo em Inglês | WPRIM | ID: wpr-94658

RESUMO

OBJECTIVES: Light-curing of resin-based materials (RBMs) increases the pulp chamber temperature, with detrimental effects on the vital pulp. This in vitro study compared the temperature rise under demineralized human tooth dentin during light-curing and the degrees of conversion (DCs) of three different RBMs using quartz tungsten halogen (QTH) and light-emitting diode (LED) units (LCUs). MATERIALS AND METHODS: Demineralized and non-demineralized dentin disks were prepared from 120 extracted human mandibular molars. The temperature rise under the dentin disks (n = 12) during the light-curing of three RBMs, i.e. an Ormocer-based composite resin (Ceram. X, Dentsply DeTrey), a low-shrinkage silorane-based composite (Filtek P90, 3M ESPE), and a giomer (Beautifil II, Shofu GmbH), was measured with a K-type thermocouple wire. The DCs of the materials were investigated using Fourier transform infrared spectroscopy. RESULTS: The temperature rise under the demineralized dentin disks was higher than that under the non-demineralized dentin disks during the polymerization of all restorative materials (p 0.05). CONCLUSIONS: Although there were no significant differences in the DCs, the temperature rise under demineralized dentin disks for the silorane-based composite was higher than that for dimethacrylate-based restorative materials, particularly with QTH LCU.


Assuntos
Humanos , Cavidade Pulpar , Dentina , Dente Molar , Polimerização , Polímeros , Quartzo , Espectroscopia de Infravermelho com Transformada de Fourier , Dente , Tungstênio
19.
The Journal of Advanced Prosthodontics ; : 491-497, 2014.
Artigo em Inglês | WPRIM | ID: wpr-99024

RESUMO

PURPOSE: This study evaluated the influence of abutment materials on the stability of the implant-abutment joint in internal conical connection type implant systems. MATERIALS AND METHODS: Internal conical connection type implants, cement-retained abutments, and tungsten carbide-coated abutment screws were used. The abutments were fabricated with commercially pure grade 3 titanium (group T3), commercially pure grade 4 titanium (group T4), or Ti-6Al-4V (group TA) (n=5, each). In order to assess the amount of settlement after abutment fixation, a 30-Ncm tightening torque was applied, then the change in length before and after tightening the abutment screw was measured, and the preload exerted was recorded. The compressive bending strength was measured under the ISO14801 conditions. In order to determine whether there were significant changes in settlement, preload, and compressive bending strength before and after abutment fixation depending on abutment materials, one-way ANOVA and Tukey's HSD post-hoc test was performed. RESULTS: Group TA exhibited the smallest mean change in the combined length of the implant and abutment before and after fixation, and no difference was observed between groups T3 and T4 (P>.05). Group TA exhibited the highest preload and compressive bending strength values, followed by T4, then T3 (P<.001). CONCLUSION: The abutment material can influence the stability of the interface in internal conical connection type implant systems. The strength of the abutment material was inversely correlated with settlement, and positively correlated with compressive bending strength. Preload was inversely proportional to the frictional coefficient of the abutment material.


Assuntos
Fricção , Articulações , Titânio , Torque , Tungstênio
20.
Chinese Medical Journal ; (24): 2819-2823, 2014.
Artigo em Inglês | WPRIM | ID: wpr-318529

RESUMO

<p><b>BACKGROUND</b>Giant cell interstitial pneumonia (GIP) was a rare form of pneumoconiosis, associated with exposure to hard metals, which had been reported mostly as isolated case reports. We described eight cases of GIP diagnosed in our hospital during the past seven years, with particular reference to new findings.</p><p><b>METHODS</b>Eight patients with GIP confirmed by biopsy in the Nanjing Drum Tower Hospital affiliated to Medical School of Nanjing University from 2005 to 2011 were retrospectively analyzed. For each patient, the occupy histories and medical records were thoroughly reviewed and clinic data were extracted. Two radiologists, without knowledge of any of the clinical and functional findings, independently reviewed the HRCT scans of all patients. Follow-up data were collected.</p><p><b>RESULTS</b>Among the eight patients, seven had a history of exposure to hard metal dusts, one denied an exposure history. The most common manifestations were cough and dyspnea. One patient initiated with pneumothorax and another pleural effusion, both of which were uncommon to GIP. The main pathologic appearances were the presence of macrophages and multinucleated giant cells in the alveolar space. The clinical symptoms and radiographic abnormalities were obviously improved after cessation of exposure and receiving corticosteroid treatments, recurrences were observed in two patients when they resumed work. In spite of exposure cessation and corticosteroid treatment, one patient developed pulmonary fibrosis at seven years follow-up.</p><p><b>CONCLUSIONS</b>Awareness of the patients' occupational history often provided clues to the diagnosis of GIP. Histopathologic examinations were necessary to establish the right diagnosis. Exposure cessation was of benefit to most patients; however, pulmonary fibrosis was possible in spite of exposure cessation and corticosteroid treatment. Better ways should be found out to improve the outcome and quality of life.</p>


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Ligas , Toxicidade , Cobalto , Toxicidade , Pulmão , Patologia , Doenças Pulmonares Intersticiais , Diagnóstico , Fibrose Pulmonar , Diagnóstico , Estudos Retrospectivos , Tungstênio , Toxicidade
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