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1.
Braz Oral Res ; 35: e29, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33605359

RESUMO

This study evaluated how Er,Cr:YSGG laser, associated or not with 5% fluoride varnish, influences the surface roughness and volume loss of bovine root dentin submitted to erosive and/or abrasive wear. One hundred and twenty dentin specimens were divided into the groups: without preventive treatment (WPT), 5% fluoride varnish (FV); Er,Cr:YSGG laser irradiation (L), and varnish combined with laser (FV + L). The specimens (n = 10) were subdivided into: 1 = erosion (E); 2 = abrasion (A); and 3 = erosion followed by abrasion (E + A). The erosive solution used was a soft-drink (pH = 2.42 at 4ºC) applied in 5-min cycles twice a day for 10d. Abrasive wear involved brushing for 60s with an electric brush (1,600-oscillations/s) at a load of 2.0N. Surface roughness and volume loss were evaluated using a laser scanning confocal microscope. Roughness data were submitted to one-way ANOVA and Tukey post-hoc test. For volume loss, the Kruskal-Wallis and Dunn's post-hoc tests were used (α = 5%). The lowest values of roughness were found in the control areas of all subgroups (p > 0.05). In the experimental area, the [(WPT) + (E+A)] subgroup had a significantly higher roughness (5.712 ± 0.163 µm 2 ) than the other subgroups (p < 0.05). The L and (FV + L) groups had statistically similar roughness, regardless of the type of wear. The (FV + L) group had the lowest volume loss, regardless of the type of wear performed: [(FV + L) + (E)] = 7.5%, [(FV + L) + (A) = 7.3%, and [(FV + L) + (E + A)] = 8.1%. The subgroup [(WPT) + (E + A)] had the highest volume loss (52.3%). The proposed treatments were effective in controlling dentin roughness. Laser irradiation can be an effective method to increase root dentin resistance after challenges and limit problems related to non-carious lesions.


Assuntos
Lasers de Estado Sólido , Erosão Dentária , Animais , Bovinos , Dentina , Fluoretos , Lasers de Estado Sólido/uso terapêutico , Erosão Dentária/etiologia , Raiz Dentária , Escovação Dentária
2.
Braz. oral res. (Online) ; 35: e29, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, BBO - Odontologia | ID: biblio-1153613

RESUMO

Abstract This study evaluated how Er,Cr:YSGG laser, associated or not with 5% fluoride varnish, influences the surface roughness and volume loss of bovine root dentin submitted to erosive and/or abrasive wear. One hundred and twenty dentin specimens were divided into the groups: without preventive treatment (WPT), 5% fluoride varnish (FV); Er,Cr:YSGG laser irradiation (L), and varnish combined with laser (FV + L). The specimens (n = 10) were subdivided into: 1 = erosion (E); 2 = abrasion (A); and 3 = erosion followed by abrasion (E + A). The erosive solution used was a soft-drink (pH = 2.42 at 4ºC) applied in 5-min cycles twice a day for 10d. Abrasive wear involved brushing for 60s with an electric brush (1,600-oscillations/s) at a load of 2.0N. Surface roughness and volume loss were evaluated using a laser scanning confocal microscope. Roughness data were submitted to one-way ANOVA and Tukey post-hoc test. For volume loss, the Kruskal-Wallis and Dunn's post-hoc tests were used (α = 5%). The lowest values of roughness were found in the control areas of all subgroups (p > 0.05). In the experimental area, the [(WPT) + (E+A)] subgroup had a significantly higher roughness (5.712 ± 0.163 μm 2 ) than the other subgroups (p < 0.05). The L and (FV + L) groups had statistically similar roughness, regardless of the type of wear. The (FV + L) group had the lowest volume loss, regardless of the type of wear performed: [(FV + L) + (E)] = 7.5%, [(FV + L) + (A) = 7.3%, and [(FV + L) + (E + A)] = 8.1%. The subgroup [(WPT) + (E + A)] had the highest volume loss (52.3%). The proposed treatments were effective in controlling dentin roughness. Laser irradiation can be an effective method to increase root dentin resistance after challenges and limit problems related to non-carious lesions.

3.
J. health sci. (Londrina) ; 21(4): https://seer.pgsskroton.com/index.php/JHealthSci/issue/view/399, 20/12/2019.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1051674

RESUMO

The objective of this in vitro study was to evaluate the influence of the Er,Cr:YSGG laser associated or not to a desensitizing agent in the treatment of erosive lesions. Forty specimens with dimensions of 4mm x 4mm and 3mm thickness were divided into 4 groups (n = 10): G1- no treatment; G2- 5% fluoride varnish; G3- Er,Cr: YSGG; G4 - fluoride varnish + laser. The specimens were immersed in erosive drink 3 times a day for 1 minute with an average interval of 2 hours between cycles for a period of 10 days. The treatments were performed according to the groups and the surface roughness and the wear profile were analyzed by scanning confocal microscopy. The normality (Kolmogorov-Smirnov) and homogeneity (Levene's) of the tests were evaluated. After these analyzes, the surface roughness data were submitted to the statistical analysis of Variance Analysis (ANOVA). All tests adopted a significance level of 5% (α = 0.05). At the representative images of the wear profile, the morphology of bovine dental enamel in its control and eroded areas were compared and qualitatively discussed. As regard surface roughness, there was no statistically significant difference between the groups. The qualitative analysis of the loss of volume showed that all experimental groups showed significant superficial morphology differences. Considering the limitations of an in vitro study, it can be concluded that the treatments performed were not able to treat dental erosion satisfactorily, indicating the need for more treatment sessions. (AU)


O objetivo desse estudo in vitro foi avaliar a influência do laser Er,Cr:YSGG associado ou não a um agente dessensibilizante no tratamento de lesões erosivas. Foram confeccionados 40 espécimes com dimensões de 4mm x 4mm e 3mm de espessura, divididos em 4 grupos (n=10): G1- nenhum tratamento; G2- verniz fluoretado 5%; G3- aplicação do laser Er,Cr:YSGG; G4- verniz fluoretado + laser. Os espécimes foram imersos em bebida erosiva, 3 vezes por dia, durante 1 minuto, com intervalo médio de 2 horas entre os ciclos, por um período de 10 dias. Os tratamentos foram realizados de acordo com os grupos e que foram analisados a rugosidade superficial e o perfil de desgaste por meio de microscopia confocal de varredura. Avaliou-se a normalidade (Kolmogorov-Smirnov) e homogeneidade (Levene's) dos dados. Após estas análises, os dados de rugosidade superficial foram submetidos ao teste estatístico de Análise de Variância (ANOVA). Todos os testes adotaram nível de significância de 5% (α=0,05). Através da obtenção das imagens representativas do perfil desgaste, a morfologia do esmalte dental bovino em suas áreas controle e erodida foram comparadas e qualitativamente discutidas. Quanto à rugosidade superficial, não houve diferença estatisticamente significativa entre os grupos. A análise qualitativa da perda de volume mostrou que todos os grupos experimentais apresentaram diferenças significativas na morfologia superficial. Considerando as limitações de um estudo in vitro pode-se concluir que os tratamentos realizados não foram capazes de tratar a erosão dentária de forma satisfatória, indicando a necessidade de mais sessões de tratamento.

4.
J. health sci. (Londrina) ; 20(4)30/12/2018.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-970569

RESUMO

The objective of this in vitro study was to evaluate the influence of different remineralizing agents in the treatment of enamel erosive lesions. Specimens of 4mmx4mm and 3mm thickness were made from the buccal surface of bovine incisors (n=10) and randomly divided into 4 groups. G1 = application of the remineralizing dentifrice, G2 = application of the remineralizing agent, G3 = remineralizing dentifrice + remineralizing agente, G4 = application of fluoride varnish (positive control), G5 = no treatment Specimens were immersed in refrigerant solution during a period of 10 days. The surface roughness was analyzed by means of confocal laser scanning microscopy. The data were analyzed for homogeneity (Levene's) and normality (Kolmogorov-Smirnov). Parametric tests with analysis of variance were performed on two criteria: time factor and treatment factor, and Tukey post-test for differentiation of means. All tests were statistically significant at 5% (α = 0.05). The results showed statistically significant difference, demonstrating the reduction of surface roughness after the first treatment (G3) and the other groups (G1, G2 and G4) only after the second treatment. It was concluded that the use of dentifrice composed of calcium silicate and sodium phosphate influenced the roughness of the eroded tooth enamel of the bovine tooth. (AU)


O objetivo deste trabalho in vitro foi avaliar a influência de diferentes agentes remineralizantes no tratamento de lesões erosivas em esmalte. Foram confeccionados espécimes de 4mmx4mm e 3 mm de espessura a partir da superfície vestibular de incisivos bovinos (n=10) e divididos aleatoriamente em 4 grupos. G1=aplicação do dentifrício remineralizante, G2= aplicação do agente potencializador remineralizante, G3= dentifrício remineralizante + agente potencializador remineralizante, G4=aplicação de verniz fluoretado (controle positivo), G5=nenhum tratamento (controle negativo). Os espécimes foram imersos em refrigerante durante um período de 10 dias. A rugosidade superficial foi analisada por meio de microscopia confocal de varredura a laser. Os dados foram analisados quanto à homogeneidade (Levene's) e normalidade (Kolmogorov- Smirnov). Foram realizados testes paramétricos com análise de variância a dois critérios: fator tempo e fator tratamento, e pós-teste de Tukey para diferenciação das médias. Todos os testes estatísticos tiveram nível de significância de 5% (α=0,05). Os resultados obtidos mostraram diferenças estatisticamente significantes, demonstrando a redução da rugosidade da superfície do esmalte logo após o primeiro tratamento (G3) e para os demais grupos (G1, G2 e G4) somente após o segundo tratamento. Concluiu-se que a utilização de dentifrício composto por silicato de cálcio e fosfato de sódio influenciou na rugosidade do esmalte erodido do dente bovino. (AU).

5.
Photomed Laser Surg ; 33(5): 266-73, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25954828

RESUMO

OBJECTIVE: The aim of this study was to assess any long-term chemical and morphological Nd:YAG laser modifications on irradiated primary enamel. BACKGROUND DATA: Previous studies on irradiated primary human enamel employed methodologies that evaluated the short-term effects only. METHODS: One hundred and eighty-six irradiated (with and/or without fluoride) primary enamel teeth from high-caries-risk children, which were exfoliated over a 1-year period, were collected, and the sample surface area was submitted for scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray energy-dispersive spectrometry (EDS). The subsurface was analyzed by Knoop microhardness and light microscopy (LM). Data were analyzed by one way ANOVA and Tukey tests (α=0.05) and Kruskall-Wallis and Tukey tests (α=0.05). RESULTS: FTIR analysis revealed a higher concentration of phosphate and carbonate in the irradiated (0.987±0.064) and lower concentration in the control groups (1.477±0.310). SEM analysis showed that the control samples exhibited a slightly smoother surface than the irradiated groups. The EDS analysis did not show any differences in the amount of calcium, phosphorus, or fluoride among the groups. The microhardness analysis revealed that sealant (249.86±7.15) and laser irradiation (262.44±22.69) led to higher hardness values than the negative control group (128.35±25.19). LM indicated significantly reduced caries formation in the laser (5.35±5.38%) and the laser plus acidulated phosphate fluoride (APF) groups (10.35±0.88%) compared with the negative control group (72.56±12.86%). CONCLUSIONS: Even with the limitations of the present study, these results suggest that Nd:YAG irradiation clinically modified the chemical composition of the enamel surface regardless of fluoride concentration, which successfully inhibited demineralization of primary tooth enamel over a 1-year period without significant morphological changes.


Assuntos
Cárie Dentária/prevenção & controle , Esmalte Dentário/patologia , Esmalte Dentário/efeitos da radiação , Lasers de Estado Sólido/uso terapêutico , Terapia com Luz de Baixa Intensidade , Fluoreto de Fosfato Acidulado/uso terapêutico , Criança , Cárie Dentária/patologia , Feminino , Humanos , Masculino , Dente Decíduo/patologia , Dente Decíduo/efeitos da radiação
6.
Lasers Med Sci ; 30(4): 1183-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24532087

RESUMO

The objective of this study was to use Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) to assess whether Nd:YAG laser irradiation associated with a dye or not alters the chemical constitution of the enamel. Fourteen enamel sections were randomly divided into two groups: (1) Nd:YAG and (2) dye + Nd:YAG. First, the untreated enamel surfaces were analyzed by FTIR to acquire the control absorption spectrum. Next, Group 2 received a layer of inactivated coal diluted in deionized water before laser treatment. Enamel samples belonging to groups 1 and 2 were then irradiated with a 1,064-nm Nd:YAG laser (80 mJ, 10 Hz) in the contact mode; the carbonate absorption band and the water absorption band were measured in each sample after irradiation. The water band was measured again 24 h, 48 h, and 7 days after irradiation. Group 1 had statistically similar water and carbonate contents before and after irradiation. Group 2 displayed significantly lower (p < 0.05) water content after irradiation, which remained constant along time at 24 and 48 h. After 7 days, the water content increased slightly, being statistically higher than in the other experimental periods, except for the control. The carbonate/phosphate ratio was measured only at the beginning, and after irradiation, it decreased only in Group 2 indicating carbonate loss (p < 0.05). Irradiation with 1,064-nm Nd:YAG laser associated with a dye reduces the carbonate and structural water content in the enamel.


Assuntos
Carbonatos/química , Esmalte Dentário/química , Lasers de Estado Sólido , Água/química , Cárie Dentária/prevenção & controle , Esmalte Dentário/efeitos da radiação , Humanos , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
7.
J Biomed Opt ; 18(10): 108003, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24145663

RESUMO

This study aimed to assess how the wear that brushing promotes affects CO2 laser-irradiated enamel microhardness after cariogenic challenge in vitro. Forty fragments measuring 4 × 4 mm were randomly assigned to four groups according to the enamel surface treatment: G1-control, G2-CO2-laser irradiation, G3-brushing, and G4-CO2 laser irradiation + brushing. A laser device emitting at 10.6 µm was used (power=0.5 W, energy per pulse=0.05 mJ, and frequency=10 kHz). Specimens belonging to groups G3 and G4 were brushed (80,000 strokes) with a brushing simulator using toothpaste. Next, the samples were challenged with acid: the specimens were immersed in demineralizing and remineralizing solutions for 8 days. The acid resistance of enamel was evaluated by cross-sectional microhardness tests. The area under the curve (KHN × µm) was calculated. Analysis of variance (ANOVA) one-away and Fisher's test were performed for the statistical analysis (p<0.05). Group G2 specimens (31,185 ± 4706) were statistically different from specimens belonging to groups G1 (26,723 ± 2446), G3 (28,194 ± 1376), and G4 (28,207 ± 2234), which were statistically similar. The brushing time used in the present study probably wore the CO2-lased enamel, so demineralization could not be prevented in the brushed group.


Assuntos
Esmalte Dentário/química , Lasers de Gás , Análise de Variância , Cárie Dentária/prevenção & controle , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/efeitos da radiação , Dureza , Humanos , Concentração de Íons de Hidrogênio , Dente Molar , Cloreto de Potássio/farmacologia , Distribuição Aleatória , Escovação Dentária
8.
RGO (Porto Alegre) ; 54(4): 351-355, out.-dez. 2006.
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-461706

RESUMO

Novas tecnologias vêm sendo testadas com o intuito de remover cárie e realizar o preparo cavitário, sem causar dor ou desconforto aos pacientes. Entre elas, o laser Er:YAG, alcançou importância clínica por mostrar-se capaz de remover o tecido dental de maneira efetiva, sem causar injúrias térmicas à polpa. Além disso, este sistema vem sendo estudado para o pré-tratamento da superfície dental, como meio de remoção de materiais restauradores estéticos e, mais recentemente, usado na prevenção de cáries secundárias e desinfecção de cavidades, visando auxiliar o cotidiano do profissional e proporcionar mais conforto ao paciente. Esta revisão de literatura esclarece de maneira crítica e objetiva os aspectos importantes da utilização do laser Er:YAG na Odontologia Restauradora.


Assuntos
Cárie Dentária/terapia , Lasers/uso terapêutico , Odontologia Preventiva
9.
Photomed Laser Surg ; 23(2): 229-32, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15910193

RESUMO

The aim of this study was to analyze in vitro the influence of Er:YAG laser focal distance variation on tensile bond strength of a composite resin to dentin. Although there are several studies using the Er:YAG laser for dentin treatment, there is a lack of available literature related to the Er:YAG laser focal distance variation. Sixty vestibular and lingual dentin surfaces from extracted human third molars, kept in a 0.4% azide sodium solution, were ground and assigned to six groups. The control group was conditioned with 35% phosphoric acid (CA). In the lased groups, the dentin surface treatment was performed by irradiation with Er:YAG laser (80 mJ/2 Hz), varying the focal distance (11, 12, 14, 16, and 17 mm), followed by acid etching. The Single Bond/Filtek Z250 (3M) resinous system was used for the specimen manufacture. The tensile bond strength tests were performed in a Universal Testing Machine with 50 kgf load cell and 0.5 mm/min cross head speed. The averages in MPa were: CA: 18.03 (+/-2.09); 11 mm; 9.92 (+/-3.34); 12 mm: 9.49 (+/-2.29); 14 mm: 10.99 (+/-3.45); 16 mm: 10.56 (+/-1.93); and 17 mm: 17.05 (+/-2.31). It was concluded that the application of Er:YAG laser in a defocused mode (17 mm) associated with acid etching was similar to the treatment of acid solely. Er:YAG laser irradiation in a focused (12 mm) and a defocused (11, 14, and 16 mm) mode coupled with acid conditioning produced the lowest values of adhesion.


Assuntos
Bis-Fenol A-Glicidil Metacrilato/efeitos da radiação , Resinas Compostas/efeitos da radiação , Colagem Dentária , Adesivos Dentinários/efeitos da radiação , Lasers , Condicionamento Ácido do Dente , Adesividade , Bis-Fenol A-Glicidil Metacrilato/química , Resinas Compostas/química , Infiltração Dentária/prevenção & controle , Restauração Dentária Permanente , Adesivos Dentinários/química , Humanos , Técnicas In Vitro , Teste de Materiais , Dente Molar , Resistência à Tração
10.
J Dent ; 32(4): 269-75, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15053909

RESUMO

OBJECTIVE: The aim of this study was to evaluate the tensile resistance of a flowable resin in different dentin depths, after superficial treatment with Er:YAG laser. METHODS: Eighteen molars were selected and roots were removed. Crowns were bisected in half, embedded in polyester resin and ground until dentin was exposed. The bonding site was delimited and samples were randomly assigned into two groups: superficial dentin (SD--1 mm from amelodentinal junction) and deep dentin (DD--2 mm from amelodentinal junction). The samples were subdivided in three groups according to superficial treatment: non-rinsing conditioner (NRC) solely; Er:YAG laser (80 mJ/2 Hz)+NRC; Er:YAG laser solely. After conditioning, Prime and Bond NT/Dyract flow (Dentsply) was used for the manufacture of specimens. They were adapted to a metallic device, where resin cones were prepared. Samples were stored for 24 h and subjected to a bond strength test (50 kgf at 0.5 mm/min). RESULTS: Means in MPa were: SD-NRC solely 12.29 (+/-4.40); laser+NRC 12.11(+/-3.23); laser solely 5.74(+/-3.01) and DD-NRC solely 9.60 (+/-3.13); laser+NRC 10.44(+/-2.23); laser solely 3.50(+/-1.70). Data were submitted to statistical analysis by ANOVA and Scheffé test (p < 0.05). CONCLUSIONS: SD produced better results and tensile bond strength, while on DD the treatment with NRC or Laser+NRC had higher tensile bond strength. The results suggest that when Er:YAG laser for dentin treatment is used, it is mandatory to associate it to a conditioning agent.


Assuntos
Resinas Compostas/química , Colagem Dentária , Adesivos Dentinários/química , Dentina/efeitos da radiação , Lasers , Condicionamento Ácido do Dente , Silicatos de Alumínio , Análise de Variância , Compômeros/química , Resinas Compostas/efeitos da radiação , Dentina/ultraestrutura , Adesivos Dentinários/efeitos da radiação , Érbio , Humanos , Maleatos/química , Ácidos Polimetacrílicos/química , Resistência à Tração , Ítrio
11.
J Clin Laser Med Surg ; 21(2): 105-8, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12737651

RESUMO

OBJECTIVE: The present study had the aim of evaluating the influence of different frequencies of the Er:YAG laser on adhesive resistance of enamel and one restorative system. BACKGROUND DATA: There have been no reports of studies assessing the influence of the pulse frequency variation of the Er:YAG laser on adhesive resistance of the enamel/resin interface. MATERIALS AND METHODS: Fifty surfaces of enamel from extracted human third molars were planed and divided into five groups at random. Enamel surface treatment was realized by the Er:YAG laser at 80-mJ power and 1-, 2-, 3-, and 4-Hz pulse frequencies, followed by etching. For the control group, only acid conditioning with 37% phosphoric acid for 15 sec was used. The Single Bond/Filtek Z250 system was chosen for the fabrication of the specimens, which were stored in 100% relative humidity for 24 h, at 37 degrees C. The specimens were submitted to tensile resistance tests using a Universal Testing Machine (50 Kgf and 0.5 mm/min). RESULTS: The mean values in MPa were 1 Hz, 25.58 (+/-6.16); 2 Hz, 25.58 (+/-3.79); 3 Hz, 21.34 (+/-3.78); 4 Hz, 21.17 (+/-3.13); and phosphoric acid only, 22.44 (+/-7.0). Data were submitted to statistical analysis using ANOVA, and there was no significant difference in tensile resistance between the studied groups. CONCLUSION: The results suggest that the Er:YAG laser, with 80-mJ power associated with acid conditioning at 1-, 2-, 3-, and 4-Hz frequencies, did not present significant improvement in tensile bonding of enamel, as compared to acid conditioning only.


Assuntos
Colagem Dentária , Esmalte Dentário/efeitos da radiação , Lasers , Condicionamento Ácido do Dente , Análise de Variância , Esmalte Dentário/efeitos dos fármacos , Humanos , Dente Serotino , Ácidos Fosfóricos , Propriedades de Superfície/efeitos dos fármacos , Propriedades de Superfície/efeitos da radiação
12.
Quintessence Int ; 33(6): 450-6, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12073726

RESUMO

OBJECTIVES: The aim of this study was to assess the ability of three low-viscosity resin systems (Unibond, Single Bond, and Fluorseal), used as rebonding agents, and a specific surface-penetrating sealant (Fortify) to prevent microleakage in Class V resin composite restorations. METHOD AND MATERIALS: Fifty Class V cavities with the occlusal margin in enamel and the cervical margin in dentin and cementum were prepared on both the buccal and lingual surfaces of sound extracted premolars and restored with a hybrid light-cured resin composite. After finishing and polishing, restorations were randomly assigned to one of five equal groups (n = 10): a control, without surface sealing, and four experimental groups in which margins were etched and rebonded. Specimens were thermocycled, immersed in a 50% silver nitrate solution, sectioned longitudinally, and analyzed for leakage at the occlusal and cervical interfaces. RESULTS: Statistical analysis showed significantly less leakage at the enamel margins for all groups. Fortify and Unibond were statistically similar and provided better marginal sealing at dentin and cementum interfaces. Fluorseal showed the poorest ability to prevent microleakage. CONCLUSION: The rebonding technique may substantially minimize microleakage at dentin and cementum margins of composite restorations, when a resin system with sufficiently low viscosity is used as a surface sealant, regardless of whether it has been specified for such a purpose.


Assuntos
Resinas Compostas/química , Colagem Dentária/métodos , Infiltração Dentária/classificação , Restauração Dentária Permanente , Adesivos Dentinários/química , Condicionamento Ácido do Dente , Bis-Fenol A-Glicidil Metacrilato/química , Cemento Dentário/ultraestrutura , Esmalte Dentário/ultraestrutura , Polimento Dentário , Restauração Dentária Permanente/classificação , Dentina/ultraestrutura , Humanos , Selantes de Fossas e Fissuras/química , Cimentos de Resina/química , Coloração pela Prata , Estatísticas não Paramétricas , Propriedades de Superfície , Termodinâmica , Viscosidade , Água/química
13.
J Adhes Dent ; 4(1): 73-80, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12071632

RESUMO

PURPOSE: The objective of this study was to evaluate the mechanical properties and bond strength of glass-ionomer cements (GICs) and resin-modified GICs (RM-GICs) that are indicated as restorative materials for the Atraumatic Restorative Treatment (ART) technique. MATERIALS AND METHODS: Fifteen disk specimens for the diametral tensile strength (DTS) test and fifteen cylindrical specimens for the compressive strength (CS) test were made of each GIC: Ketac-Fil, Ketac-Molar (ESPE), Fuji IX and Fuji PLUS (GC). Forty human molars were sectioned and embedded in resin with either buccal or lingual surfaces exposed for the tensile bond strength (TBS) test. The surface was ground until a flattened area of enamel or dentin was obtained. After conditioning, inverted truncated cones of GICs were prepared on the flat tooth surfaces. The powder:liquid ratio of Fuji PLUS was adjusted for restorative purposes. Prior to testing, specimens were stored for 24 h (TBS test) and for 1 h, 24 h, and 7 days (CS and DTS tests) in deionized water at 37 degrees C. They were then loaded at a crosshead speed of 1.0 mm/min for CS and 0.5 mm/min for DTS and TBS tests until failure occurred. The data were submitted to two-way ANOVA at 0.05 level of significance, followed by a Tukey-Kramer test for multiple comparisons. RESULTS: The mean CS values ranged from 90.27 to 170.73 MPa and DTS means from 6.21 to 22.32, with test periods from 1 h to 7 days. The means for TBS ranged from 4.90 to 11.36 MPa and from 2.52 to 5.55 MPa in enamel and dentin, respectively. No differences were found between materials with the CS test except at 1 hour. The resin-modified GIC (RM-GIC) had the highest DTS, with no changes between the test periods, and the highest TBS for both enamel and dentin. CONCLUSION: Among the GICs tested, RM-GIC showed higher values of DTS and TBS.


Assuntos
Colagem Dentária , Cimentos de Ionômeros de Vidro/química , Análise de Variância , Força Compressiva , Preparo da Cavidade Dentária/métodos , Esmalte Dentário/ultraestrutura , Restauração Dentária Permanente/métodos , Dentina/ultraestrutura , Humanos , Maleatos/química , Dente Molar , Cimentos de Resina/química , Estatística como Assunto , Estresse Mecânico , Temperatura , Resistência à Tração , Fatores de Tempo , Água/química
14.
Rev. odontol. UNESP ; 30(1): 75-86, jan.-jun. 2001. ilus, tab
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-329220

RESUMO

O propósito deste estudo foi avaliar in vitro a infiltraçäo marginal de duas resinas compostas modificadas por poliáciso - F2000(3M) e Freedom (SDI) - comparando-as a um cimento de ionômero de vidro modificado por reina - Vitremer (3M). Para tanto, 30 preparos classe V - com 2 mm de profundidade e dimensöes mesiodistal e ocluso-gengival de 4 mm e 3 mm, respectivamente - foram confeccionados em pré-molares e caninos humanos e divididos aleatoriamente em 3 grupos iguais (n=10). As cavidades foram tratadas e entäo restauradas seguindo-se as instruçöes da bula de cada material. Os dentes ficaram armazenados por 7 dias em 100 por cento de umidade relativa a 37ºC em estufa e após esse período foi realizado o polimento. Os espécimes foram submetidos a ciclagem térmica (600 ciclos), impermeabilizados com esmalte cosmético, deixando-se uma janela de 1 mm em torno da restauraçäo sem isolar, e a seguir foram imersos em soluçäo de nitrato de prata a 50 por cento por 8 horas. Os dentes foram lavados, incluídos em resina acrílica, seccionados longitudinalmente e avaliados seguindo-se escores de 0 a 3. A análise estatística dos dados pelos testes de Wilcoxon e Kruskall-Wallis revelou que na regiäo de esmalte os materiais testados apresentaram completo vedamento marginal em praticamente todos os espécimes, näo havendo diferença estatística significante entre eles. Na margem dentina/cemento, o Vitremer e o F2000 promoveram melhor selamento quanto comparados ao Freedom, que apresentou os resultados mais insatisfatórios. Com base nesses dados pode-se concluir que nenhum dos materiais testados propiciou completo vedamento da margem com término cervical em dentina/cemento


Assuntos
Compômeros , Cimentos de Ionômeros de Vidro , Infiltração
15.
RGO (Porto Alegre) ; 48(3): 153-154, jul.-set. 2000. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-321888

RESUMO

Como tratamento restaurador estético de dentes anteriores fraturados, podemos lançar mäo de materiais de uso direto como as resinas compostas e a colagem do fragmento dental, ou indireto, como as coroas totais de porcelana. Entretanto, quando há perda do fragmento dental, pode-se optar por uma técnica conservadora e econômica, que baseia-se na utilizaçäo de fragmentos feitos de dentes armazenados em um banco de dentes. O presente trabalho propôs a realizaçäo de uma colagem homógena, em paciente de treze anos como técnica alternativa para restabelecimento da funçäo e estética do incisivo central fraturado, evitando-se desta forma, utilizar um tratamento protético mais radical e conseqüentemente de custo mais elevado


Assuntos
Humanos , Masculino , Adolescente , Colagem Dentária/métodos , Fraturas dos Dentes
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