RESUMO
AIM: It is very important to perform studies to evaluate micro-hardness and curation level at different depths to refine the clinical indications and orientations that the odontologist gives to the patients, helping to achieve more durable treatments when using resin-modified glass ionomers. This in vitro study evaluated knoop micro-hardness in 2 different brands of resin-modified glass ionomers: Ketac ™ N100 (M1) and Fuji II LC (M2). METHODS: Tests were performed at three depths: surface (P1), 2 mm (P2) and 3 mm (P3). A total of 40 samples where made (20 of each type of resin), half of these measuring 5 x 2 mm and the other half with 5 x3 mm. To evaluate micro-hardness at different depths, 24 hours after the manufacture of samples, tests where made on both top and bottom surfaces. These tests were performed using an HMV-200 Micro Hardness Tester (Shimadzu brand). For statistical analysis data were collected and used first for ANOVA variance analysis (P≤0.01) followed then by Turkey's test. RESULTS: It also shows that the effect is not significant for the interaction between material and depth. Micro-hardness on P1 (34.7) is statistically greater than with P2 (29.2) and P3 (29.0) and these last two are statistically equal between them. M1 (27.8) presented less micro-hardness than M2 (34.2). CONCLUSION: Surface micro-hardness is greater than micro-hardness at other depths and M2 presented better results than M1.
Assuntos
Cimentos de Ionômeros de Vidro , Óxido de Magnésio , Cimento de Policarboxilato , Cimentos de Resina , Resinas Sintéticas , Óxido de Zinco , Testes de Dureza , Teste de Materiais , Propriedades de SuperfícieRESUMO
AIM: The aim of this in vitro study was to evaluate the diametral compressive bond strength between Charisma or TPH composite resin after association or not to an adhesive system in incremental filling technique. METHODS: Twenty cylinders of each composite resin brand were fabricated using a Teflon matrix and divided into four groups, according to the numbers of adhesive layers applied: group 1 Control without adhesive; group 2 one layer; group 3 two layers and group 4 three layers. The bonding system Adper Single Bond was used between composite resin increments. Diametral compression assays were carried out in an EMIC-MEM 2000 universal testing machine, adjusted at 1 mm/min. ANOVA and Tukey's test were used in the statistical analysis. RESULTS: The mean strengths and standard deviations for each group were: Charisma 1= 38.26+/-2.38; 2=46.56+/-2.38; 3=40.57+/-2.38; 4=36.87+/-2.38 (2>1=3=4; P<0.05) and TPH 1=52.17+/-2.38; 2=52.23+/-2.38; 3=44.68+/-2.38; 4=44.11+/-2.38 (1=2>3=4; P<0.05). CONCLUSIONS. It was concluded that TPH presented higher means of compressive bond strength than Charisma, and the association of an adhesive system between the increments may influence the diametral compressive bond strength of composite resins.
Assuntos
Resinas Compostas , Força Compressiva , Colagem Dentária , Cimentos Dentários , Restauração Dentária Permanente/métodos , Humanos , Teste de MateriaisRESUMO
AIM: Amalcomp is a technique that combines composite resin to amalgam in restorative procedures to improve esthetics and minimize the negative effects of polymerization on dental tissues. The objective of this in vitro study was to measure the diametral compressive bond strength between Fill Magic composite (Vigodent) versus Permite (DFL) or Velvalloy (SS White) amalgams in different oxidation stages. METHODS: Twenty-four cylinders of each amalgam brand were fabricated using a Teflon matrix and divided into 3 groups according to the immersion period in artificial saliva for oxidation: A (1 day), B (7 days) and C (30 days). After immersion, the amalgam cylinders were bonded to the composite specimens using the Scotch Bond Multi Use Plus (3M) bonding system. Diametral compression assays were then carried out in an EMIC-MEM 2000 universal testing machine set to 0.5 mm/min. Statistical analysis was performed using ANOVA and Tukey's test. RESULTS: The mean recorded strength (MPa) for each oxidation group was: A=9.71, B=8.21 and C=6.98 (A>B = C; P<0.01). Permite (7.24) provided significantly less adhesion to the composite than Velvalloy (9.36; P<0.05). There was no interaction between the factors alloy, resin and time. CONCLUSIONS: Under the conditions of this study, the less oxidized amalgam showed the greatest diametral compressive strength values.
Assuntos
Resinas Compostas/química , Ligas Dentárias/química , Amálgama Dentário/química , Colagem Dentária , Força Compressiva , Cobre/química , Teste de Materiais , Oxirredução , Saliva Artificial/química , Prata/química , Fatores de TempoRESUMO
O alginato ou hidrocolóide irreversível é um dos materiais de moldagem mais aceitos e utilizados na Odontologia. Muitas substâncias como zinco, cádmio, silicato de chumbo e fluoretos foram adicionadas em algumas marcas de alginatos, com o objetivo de melhorar suas propriedades físicas, químicas, mecânicas e se tornaram causa de preocupação no que se refere à toxicidade desses materiais. Em algumas marcas de alginatos relatou-se a presença de fluoretos, cádmio, silicatos de chumbo e zinco potencialmente tóxicos, isoladamente ou em conjunto, consequentemente, cuidados especiais devem ser tomados na preparação desses materiais. É necessário que haja um controle contínuo de metais e substâncias potencialmente tóxicas nos alginatos para se evitar a contaminação dos profissionais da área odontológica e pacientes. Nesta revisão analisou-se o potencial tóxico de alginatos usados em odontologia.
Assuntos
Alginatos/toxicidade , Materiais para Moldagem Odontológica/toxicidade , Cádmio/toxicidade , Chumbo/toxicidade , Fluoretos/toxicidade , Zinco/toxicidadeRESUMO
Alginate is one de materials most employed in practice to make dental impressions. Substances like zinc, cadmium and lead silicate, which are included in several alginate brands with the aim of improving their physical, chemical and mechanical properties, are a source of serious concern regards their toxicity. The most serious chronic effect of oral exposure to cadmium is renal toxicity. Assimilation of lead has deleterious effects on the gastrointestinal tract, hematopoietic system, cardiovascular system, central and peripheral nervous systems, kidneys, immune system, and reproductive system. Chronic oral exposures to zinc have resulted in hypochromic and microcyte anemia in some individuals. The aim of the present study was to measure the cadmium, lead and zinc contents of seven brands of alginate for dental use on sale in Brazil. The samples were weighed and placed in the Teflon cups of a closed-system microwave oven. Aqua regia (4 mL concentrated HCl:HNO3, 3:1 v/v) and hydrofluoric acid (2mL concentrated HF) were added to the samples, which were then subjected to heating. The samples were then cooled to room temperature and diluted to 25 mL in deionized water in a volumetric glass flask. The samples were diluted in duplicate and analyzed against a reagent blank. The analyses were performed in an atomic absorption flame spectrophotometer. Neither lead nor cadmium was detected. Zinc contents ranged from 0.001% to 1.36% by weight. The alginates exhibited low contents of the metals under study and gave no cause for concern regarding toxicity; even so, it is advisable to monitor potentially toxic materials continually and to analyze their plasmatic levels in the professionals working with them
Assuntos
Alginatos/análise , Alginatos/uso terapêutico , Metais Pesados , Odontologia/métodos , Estudos de Avaliação como Assunto , Cádmio/toxicidade , Chumbo/toxicidade , Zinco/toxicidadeRESUMO
Este trabalho teve como proposta analisar quantitativamente o conteúdo de fluoretos nos alginatos para uso odontológico e a liberação de fluoretos de moldes desses alginatos em água milliQ,saliva artificial e ácido clorídrico 0,1 mol/l.Foram investigadas sete marcas de alginatos disponíveis comercialmente no Brasil, sendo analisados dois lotes de cada material.As concentrações de fluoretos nas diferentes amostras foram determinadas por potenciometria direta, utilizando o eletrodo seletivo combinado de fluoreto.Os materiais que apresentaram maiores concentrações médias de fluoreto total foram Hydrogum (7052,87μg/g), Jeltrate Plus (6519,68μg/g) e Orthoprint (6218,18μg/g).Apenas os materiais das marcas Hydrogum e Jeltrate apresentaram diferenças nas concentrações de fluoretos entre os lotes um e dois.Os materiais apresentaram diferenças na liberação de fluoretos dos moldes, cujas maiores concentrações médias foram liberadas pelas marcas Hydrogum e Orthoprint.O meio influenciou na liberação de fluoreto, sendo que na saliva foi menor que na água e nesta foi inferior ao ácido.Os moldes dos materiais que mais liberaram fluoretos nos três meios (saliva, água e ácido) foram os do Hydrogum e Orthoprint.Considerando que as concentrações de fluoretos encontradas nos alginatos são altas e que existem diferentes fontes de exposição aos fluoretos, há necessidade de constante monitoramento dos alginatos para uso odontológico
Assuntos
Alginatos/análise , Fluoretos/análise , Materiais Dentários/toxicidadeRESUMO
The aim of this study was to evaluate in vivo the use of low-level galium-aluminium-arsenide (GaAlAs) (BDP 600) laser and sodium fluoride varnish (Duraphat) in the treatment of cervical dentine hypersensitivity. Twelve patients, with at least two sensitive teeth were selected. A total of 60 teeth were included in the trial. Prior to desensitizing treatment, dentine hypersensitivity was assessed by a thermal stimulus and patients' response to the examination was considered to be a control. The GaAlAs laser (15 mW, 4 J/cm2) was irradiated on contact mode and fluoride varnish was applied at cervical region. The efficiency of the treatments was assessed at three examination periods: immediately after first application, 15 and 30 days after the first application. The degree of sensitivity was determined following predefined criteria. Data were submitted to analysis and no statistically significant difference was observed between fluoride varnish and laser. Considering the treatments separately, there was no significant difference for the fluoride varnish at the three examination periods, and for laser therapy, significant difference (P < 0.05) was found solely between the values obtained before the treatment and 30 days after the first application. It may be concluded that both treatments may be effective in decreasing cervical dentinal hypersensitivity. Moreover, the low-level GaAlAs laser showed improved results for treating teeth with higher degree of sensitivity.
Assuntos
Sensibilidade da Dentina/terapia , Fluoretos Tópicos/administração & dosagem , Terapia com Luz de Baixa Intensidade , Fluoreto de Sódio/administração & dosagem , Adulto , Feminino , Seguimentos , Temperatura Alta/efeitos adversos , Humanos , Masculino , Resultado do TratamentoRESUMO
Due to the great importance that antiseptic solutions have on the control and prevention of oral diseases and their influence on the translucence of esthetic restorative materials, the present study evaluated the effect of antiseptic solutions on the translucence of two glass-ionomer cements, Vidrion R and Chelon Fil, at eight time periods. Four antiseptic solutions were used: Listerine, Malvona, Flogoral and Plax. Vidrion R was less translucent than Chelon Fil. Translucence decreased with longer observation time and Malvona caused the lowest translucence.