Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 55
Filtrar
1.
Gen Dent ; 64(5): 75-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27599287

RESUMO

Enamel defects, such as white or yellow-brown spots, usually cause problems that are more esthetic than functional. Enamel hypoplasia may be the result of hereditary, systemic, or local factors. Dental trauma is a local etiologic factor. It is relatively common in the primary dentition and can cause defects on the surface of permanent successors. Treatment for such defects can differ, depending on the depth of the spots. For deeper white-spot lesions, a composite resin restoration may be necessary. This is an excellent mode of treatment, due to both its low cost and its conservation of healthy tooth structure. The objective of this case report is to describe composite resin restoration of a maxillary central incisor affected by enamel hypoplasia.


Assuntos
Hipoplasia do Esmalte Dentário/cirurgia , Restauração Dentária Permanente/métodos , Adolescente , Resinas Compostas/uso terapêutico , Hipoplasia do Esmalte Dentário/diagnóstico , Estética Dentária , Feminino , Humanos , Incisivo/cirurgia
2.
Dent Mater ; 31(11): 1385-95, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26411647

RESUMO

OBJECTIVES: The aim of this study was to evaluate the formation of dentin bonding interfaces using the water-wet and the ethanol-wet techniques under simulated pulpal pressure, and to assess the effect of adhesive solvent and thermomechanical loading. METHODS: Flat dentin surfaces were restored under 20mm-simulated pulpal pressure following two bonding approaches (water-wet and ethanol-wet bonding) in combination with dental adhesives containing ethanol (Single Bond Plus and Scotchbond Multi-Purpose) or acetone (One-Step Plus and All-Bond 2) as solvent. Half of the restorations of each subgroup were subjected to thermocycling followed by cyclic loading (three teeth per group). Bond strength was measured using the microtensile bond strength test and fitted to a Weibull distribution (α=0.05). Ultrastructural analyses of the interface and leakage/nanoleakage evaluation were performed using confocal scanning microscopy (CLSM) and transmission electron microscopy (TEM). RESULTS: Water permeation through dentin tubules during adhesive application prevented adequate penetration of adhesive monomers into the demineralized collagen matrix in both bonding techniques, but more severely for water-wet bonding. Acetone-solvated adhesives showed worse bonding performance and hybridization than ethanol-based systems when applied in the ethanol-wet mode, both before and after thermomechanical challenge. SIGNIFICANCE: The ethanol-wet bonding technique helps to compensate for water permeation from dentin tubules during the bonding procedures to form more stable dentin bonds, especially when used in conjunction to ethanol-solvated systems.


Assuntos
Cimentos Dentários , Adesivos Dentinários , Cimentos de Resina , Colagem Dentária , Dentina , Etanol , Teste de Materiais , Microscopia Eletrônica de Varredura , Resistência à Tração , Água
3.
RSBO (Impr.) ; 12(2): 179-184, Apr.-Jun. 2015. tab
Artigo em Inglês | LILACS | ID: lil-792041

RESUMO

Introduction: The rehabilitation of teeth by means of ceramic indirect restorations has been widely performed. Previous studies has shown the effectiveness of silane coupling agents on improving the bond strength of the adhesion of resin cements to ceramics; however, some studies question the use of silane. Objective: To evaluate the effect of silane application on the microtensile bond strength of an auto-adhesive luting material to a lithium disilicate glass-ceramic. Material and methods: Two blocks (9x11x4mm) of lithium disilicate glass-ceramic had one of their surfaces polished (# 220, 360, 600 grit silicon-carbide abrasive papers) and cleaned ultrasonically. The ceramic blocks were then divided into two groups according to the surface treatment: G1 (control group): etched with 10% hydrofluoric acid for 20s and silane coated; G2: etched with 10% hydrofluoric acid for 20s. After building two blocks of composite resin (Filtek Z350) with the same dimensions of the ceramic blocks, the self-adhesive resin cement (SpeedCEM) was applied directly to the ceramic surface and the resin block was seated on the cement. After storage (24h, 37°C), the ceramic-cement-composite blocks were cut with an Isomet low-speed diamond saw machine producing sticks, which were loaded to failure at a crosshead speed of 0.5 mm/min. The type of fracture was analyzed under an optical microscope. The results were statistically analyzed using the Student t test. Results: The mean microtensile and standard deviations in megaPascals were: G1 = 21.32 (± 4.36) and G2 = 16.55 (± 4.92). Statistical analysis showed that the bond strength was not significantly affected by the surface treatment with silane. Most of the fractures occurred within the adhesion zone. Conclusion: The application of silane had no significant effect on the bond strength between lithium disilicate glass-ceramic and self-adhesive resin cement.

4.
Braz. j. oral sci ; 14(1): 31-35, Jan-Mar/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-745779

RESUMO

To evaluate the bond strength of brackets bonded after different surface treatments on two dental ceramics. METHODS: One hundred and twenty discs 5 mm thick and 7 mm diameter of two ceramic types were made and randomly divided in 8 groups. Groups 1, 3, 5, and 7 used Eris ceramic and groups 2, 4, 6, and 8 used d.Sign ceramic. The ceramic surfaces were treated with 10% hydrofluoric acid G1 and G2, 10% hydrofluoric acid + silane G3 and G4, aluminum oxide blasting + 35% phosphoric acid + silane G5 and G6, CoJet blasting + 35% phosphoric acid + silane G7 and G8. Metallic brackets were cemented with Concise cement. Mechanical test was performed in a universal testing machine until failure. RESULTS: The average values MPa obtained G1 - 7.30; G2 - 6.12; G3 - 17.49; G4 - 19.54; G5 - 18.80; G6 - 21.93; G7 - 6.81 e G8 - 9.77 were submitted to ANOVA and Tukey test p<0.05. The fracture patterns were analyzed in stereoscopic microscope 25´X and representative samples of each group were analyzed in SEM. CONCLUSIONS: It was possible to conclude that use of silane after hydrofluoric acid increased the bond strength values...


Assuntos
Humanos , Adesivos , Colagem Dentária , Porcelana Dentária , Braquetes Ortodônticos , Resistência ao Cisalhamento , Ácido Fluorídrico , Silanos
5.
Clín. int. j. braz. dent ; 10(3): 294-302, jul.-set.2014. ilus, tab, graf
Artigo em Português | LILACS | ID: lil-757788

RESUMO

Uma superfície de cada um de quatro blocos foi polida e submetida aos seguintes tratamentos de superfície: bloco A (HF+S) - microjateamento com Al2O3 de 50 μm (15 s), condicionamento com ácido HF a 9,5% (20 s) e aplicação de silano (3 min); bloco B (HF) - microjateamento e condicionamento com ácido HF; bloco C (S) - microjateamento e silano; e bloco D (CJ) - microjateamento com CoJet Sand e aplicação de silano. O adesivo Scotchbond Multi-Purpose Plus foi aplicado sobre a superfície dos blocos A, B e C, e o adesivo Visio-Bond do sistema CoJet, no D, todos polimerizados, e resina composta (Filtek Z250) foi adicionada em quatro incrementos de 1 mm e fotopolimerizada. Os blocos de resina-cerâmica foram, então, seccionados em dois eixos perpendiculares, produzindo cada um aproximadamente 40 corpos de prova, divididos em dois grupos: grupo “Imediato”, dividido em quatro subgrupos: HF+S/I (n = 19), HF/I (n = 19), S/I (n = 20) e CJ/I (n = 16), armazenados por 24 h em água destilada; e grupo “12m+Tc”, dividido em quatro subgrupos: HF+S/12m (n = 20), HF/12m (n = 20), S/12m (n = 20) e CJ/12m (n = 17), armazenados por 12 meses em saliva artificial, seguidos por termociclagem (800 ciclos). Os valores médios obtidos (HF+S/I = 56,85±16,52(a), HF/I = 51,69±11,34(ab), S/I = 50,73±12,37(ab), CJ/I = 40,13±9,27(bc), HF+S/12m = 42,29±17,34(b), HF/12m = 21,03±7,02(d), S/12m = 13,72±6,24(d), CJ/12m = 26,77±21,07(cd)) foram analisados estatisticamente (ANOVA 2). Observou-se interação entre tratamento de superfície e condição de armazenamento. Condicionamento da superfície cerâmica com ácido HF combinado com silanização propiciou maior μ-TBS à resina após 12 meses de armazenamento em saliva artificial e termociclagem...


One surface of each out of four blocks was polished and subjected to the following surface treatments: A: (HF + S) – sandblasting with AL2O3 50 μm (15 s), etching with 9.5% HF (20 s) and silane application (3 min); B:(HF) - sandblasting and etching with HF; C: (S) – sandblasting and silane; D: (CJ) – sandblasting with CoJet Sand and silane application. A three-step total-etch adhesive was applied (ScotchBond Multi-Purpose Plus) on the surface of the blocks A, B, and C, and the light-cured bonding material, proprietary of the CoJet system (Visio-Bond) on block D, light-cured, and composite resin (Filtek Z250) was added in four 1 mm increments and light cured. The ceramic-resin blocks were then sectioned into two perpendicular axes, each producing approximately 40 specimens, divided into two groups: “immediate” group divided into four subgroups: HF + s / i (n = 19) , HF / i (n = 19), S / I (n = 20) and cj / i (n = 16), stored for 24 h in distilled water; and group “12m + tc”, divided into four subgroups: s/12m + HF (n = 20) HF/12m (n = 20) s/12m (n = 20) and CJ/12m (n = 17) stored for 12 months in artificial saliva followed by thermocycling (800 cycles). The obtained average values (HF + s / i = 56.85 ± 16.52 (a) HF / i = 51.69 ± 11.34 (ab) s / i = 50.73 ± 12.37 (ab), CJ/ i = 40.13 ± 9.27 (bc) + HF s/12m = 42.29 ± 17.34 (b), HF/12m = 21.03 ± 7.02 (d), s / 12m = 13.72 ± 6.24 (d), 26.77 ± 21.07 CJ/12m = (cd)) were statistically analyzed (2-way ANOVA). Interaction between surface treatment and storage conditions were observed. Conditioning of the ceramic surface with HF associated with silanization provided greater μ-TBS values to resin after 12 months of storage in artificial saliva and thermocycling...


Assuntos
Humanos , Cerâmica , Restauração Dentária Permanente , Resinas Sintéticas , Silanos
6.
Braz Oral Res ; 282014.
Artigo em Inglês | MEDLINE | ID: mdl-24918366

RESUMO

The purpose of this study was to evaluate the influence of buccal and lingual wall thickness on the fatigue resistance of molars restored with CAD/CAM ceramic inlays. Forty human third molars were selected and divided into 4 groups, according to the remaining surrounding wall thickness chosen for inlay preparation (n=10): G1, 2.0 mm; G2, 1.5 mm; G3, 1.0 mm; G4, 0.5 mm. All inlays were made from feldspathic ceramic blocks by a CAD/CAM system, and cemented adhesively. After 1 week stored in distilled water at 37 °C, the specimens were subjected to fatigue testing under the following protocol: 5Hz; pre-load of 200 N for 5,000 cycles, followed by increasing loads of 400, 600, 800, 1000, 1200 and 1400 N for 30,000 cycles each. The specimens were cycled until failure or completion of 185,000 cycles. The survival rate of the groups was compared using the Kaplan-Meier survival curves (p>0.05). All specimens withstood the fatigue protocol (185,000 cycles), representing a 100% survival rate. The Kaplan-Meier survival curves showed no difference between groups. It can be concluded that the remaining tooth wall thickness did not influence the fatigue resistance of molars restored with CAD/CAM ceramic inlays.


Assuntos
Cerâmica/química , Restaurações Intracoronárias/métodos , Dente Molar/anatomia & histologia , Desenho Assistido por Computador , Cimentos Dentários/química , Falha de Restauração Dentária , Análise do Estresse Dentário , Humanos , Estimativa de Kaplan-Meier , Teste de Materiais , Valores de Referência , Reprodutibilidade dos Testes , Propriedades de Superfície , Fatores de Tempo
7.
Clin Oral Investig ; 18(2): 515-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23716064

RESUMO

OBJECTIVES: The aim of this in vitro study was to evaluate the marginal and internal fit of CAD/CAM-generated four-unit zirconia fixed dental prostheses made with digital and conventional impressions. MATERIALS AND METHOD: A titanium master model was used. For group conventional impression (CI), 12 polyether impressions of the master model with Impregum(TM) were made. For group digital impression (DI), 12 digital impressions of the master model using Lava(TM) C.O.S. system were made. The replica technique was applied. The Mann-Whitney U statistical test was applied to detect statistical differences between the groups, in terms of marginal and internal fit. Face-by-face comparisons between groups were also carried out. RESULTS: Groups DI and CI presented mean marginal fit of 63.96 and 65.33 µm, respectively, and showed no statistically significant difference. Groups DI and CI presented significantly different internal fit with mean values of 58.46 and 65.94 µm, respectively. Group DI showed statistically significantly lower values for marginal and internal fit on premolar mesial face, and on molar distal and palatal faces. CONCLUSIONS: Frameworks fabricated from digital and conventional impressions showed clinically acceptable marginal fit. Frameworks fabricated from digital impression demonstrated better internal fit than ones fabricated from conventional impression. Reviewing each retainer face, digital impression showed better marginal and internal fit at the premolar mesial and molar distal faces. CLINICAL RELEVANCE: The results of this in vitro study show that digital impressions made with the Lava(TM) C.O.S. system and its digital workflow are suitable for fabricating four-unit zirconia frameworks, with regard to marginal and internal fit requirements.


Assuntos
Técnica de Moldagem Odontológica , Prótese Dentária , Zircônio , Estudos de Casos e Controles , Humanos
8.
Clín. int. j. braz. dent ; 9(4): 448-455, out.-dez. 2013. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-786188

RESUMO

A contração de polimerização ainda é um grande inconveniente dos materiais restauradores adesivos diretos. Com o objetivo de minimizar esse problema, foram introduzidas no mercado resinas de baixa contração. Uma delas é a resina à base de silorano, que combina as vantagens do silorano, o qual lhe confere hidrofobicidade, e o oxirano, que resulta em baixa contração volumétrica. Assim, por suas boas propriedades mecânicas e baixa contração volumétrica, ela é indicada para restaurações em dentes posteriores. O objetivo do presente artigo é apresentar o caso clínico de uma restauração de classe I realizada com resina de baixa contração à base de silorano.


Polymerization shrinkage is a major drawback of direct restorative materials. In order to minimize this problem, low-shrinkage composite resins were introduced. Silorane-based composites combine the advantages of the silorane, which conveys hydrophobicity, and oxirane which results in low volumetric shrinkage. They are indicated for restorations in posterior teeth due to their suitable mechanical properties and low shrinkage. The aim of this paper is to present a clinical case of a Class I restoration performed with low shrinkage silorane-based composite resin.


Assuntos
Humanos , Masculino , Resinas Compostas , Restauração Dentária Permanente , Resinas de Silorano
9.
Clín. int. j. braz. dent ; 8(4): 438-452, out.-dez. 2012. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-740481

RESUMO

As LCNCs apresentam etiologia multifatorial e expressão crescente na clínica diária. Seu estudo é cada vez mais necessário, para possibilitar correto diagnóstico, tratamento e prevenção. A resina composta apresenta–se como melhor material para restaurar as LCNCs com estética e funcionalidade. Outra grande vantagem dela é o selamento da dentina cervical exposta, que elimina a sensibilidade e traz, assim, conforto ao paciente. Todavia, a adoção de um protocolo criterioso, especialmente nas etapas do isolamento do campo operatório, aplicação do sistema adesivo, inserção da resina composta, acabamento e polimento, é essencial para o sucesso restaurador. Sendo assim, a parte II desta série apresenta dois protocolos clínicos como sugestões para se obterem resultados mais previsíveis, com base em uma interpretação conservadora da literatura.


NCCLs presente multifactorial etiology and increased prevalence in the daily practice. Its study is increasingly necessary to enable correct diagnosis, treatment and prevention. Composite resin has shown to be material of choice to restore NCCLs with esthetics and function. Another great advantage is sealing of exposed cervical dentin, eliminating tooth sensitivity, thus bringing comfort to the patient. However, the adoption of a careful protocol, especially in the steps of isolation of the operative field, application of adhesive system, insertion of composite resin, finishing and polishing, is essential for successful restorations. Therefore, the second part of this three-part series presents two suggestions of clinical protocols to obtain more predictable results, based on a conservative approach of the literature.


Assuntos
Humanos , Animais , Feminino , Adulto , Resinas Compostas , Estética Dentária , Abrasão Dentária , Erosão Dentária
10.
Clín. int. j. braz. dent ; 8(1): 34-46, jan.-mar. 2012. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-716588

RESUMO

As lesões cervicais não cariosas (LCNCs) são cada vez mais prevalentes, tanto em jovens quanto em adultos e idosos. Elas são consideradas um dos novos desafios da odontologia. Inúmeras controvérsias ainda perduram na literatura, dificultando o diagnóstico e tratamento desse tipo de lesão. Diversos materiais têm sido utilizados na restauração delas, sendo as resinas compostas a principal opção. Este artigo, que é uma parte de dois, apresenta uma breve revisão da literatura sobre as LCNCs. Nesta parte, são abordados pontos importantes, como definição, epidemiologia, implicações clínicas, tratamento, variáveis que influenciam a adesão e a seleção do material e por que utilizar resina composta.


Non carious cervical lesions (NCCLs) became increasingly prevalent, both in young and adults, and are considered a new challenge in Dentistry. Numerous controversies still exist in the literature, difficulting the diagnosis and treatment of this type of lesion. Various materials have been used to restore these lesions, and composite resins are the material of choice. This article, the first of two-part study, presents a brief review of the literature on NCCLs. This will address important points, such as definition, epidemiology, clinical implications, treatment, variables that influence the adhesion, material selection and why using composite resins.


Assuntos
Resinas Compostas , Estética Dentária , Abrasão Dentária , Erosão Dentária
11.
J Adhes Dent ; 13(2): 139-45, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21594227

RESUMO

PURPOSE: To compare the bond strengths of young and old dentin using a single-bottle etch-and-rinse adhesive system with two acid-etching times (15 s and 30 s), and to examine the correlation between dentin hardness and bond strength. MATERIALS AND METHODS: Twenty-four molars from 18- to 22- or 55- to 60-year-old patients were prepared to expose the occlusal dentin, cut into two equal parts, and assigned to four groups (G), varying the etching time (15 s and 30 s) and dentin age (young [Y]or old [O]): G15Y, G30Y, G15O and G30O. After etching, AdperSingleBond (3M ESPE) adhesive was applied and the tooth was built up with a composite (Filtek Z250). The specimens were prepared for the microtensile bond strength test (µTBS) at a crosshead speed of 0.5 mm/min and the interfaces were observed under SEM. Also, the Knoop hardness (KHN) of young vs old dentin was measured. RESULTS: The mean (± SD) µTBS (MPa) were: G15Y = 45.9 (± 10.7)a, G15O = 34.1 (± 9.4)b, G30Y = 48.6 (± 14.3)a and G30O = 47.7 (± 11.0)a. Two-way ANOVA showed no difference in µTBS between young and old dentin. Old dentin acid etched for 15 s (G15O) had a lower µTBS than when acid etched for 30 s (G30O). Dentin hardness was higher for old dentin (67.0 ± 4.8KHN) than young dentin (63.7 ± 2.9KHN) (p < 0.004). No correlation between µTBS and dentin hardness was observed. Resin tags were larger and more numerous for young dentin. The hybrid layer formed in intertubular old dentin (G15O) was very thin. CONCLUSION: Bonding to old dentin with 30 s of etching time resulted in higher bond strength and more homogeneous hybrid layer formation than dentin acid etched for 15 s.


Assuntos
Condicionamento Ácido do Dente/métodos , Envelhecimento/fisiologia , Colagem Dentária , Dentina/fisiologia , Adolescente , Envelhecimento/patologia , Análise de Variância , Bis-Fenol A-Glicidil Metacrilato , Resinas Compostas , Restauração Dentária Permanente/métodos , Adesivos Dentinários , Dureza , Humanos , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Esclerose , Fatores de Tempo , Adulto Jovem
12.
Clín. int. j. braz. dent ; 7(1): 106-117, jan.-mar.2011. ilus
Artigo em Português | LILACS | ID: lil-757829

RESUMO

Desde seu surgimento, os pinos fibrorresinosos têm sido muito utilizados na restauração de dentes tratados endodonticamente. Apesar do desenvolvimento nos últimos anos das técnicas adesivas, vários estudos têm demonstrado haver um importante percentual de falhas adesivas na interface pino-cimento resinoso. Dessa forma, a presente revisão de literatura expõe diferentes protocolos clínicos sugeridos na literatura científica e as novas possibilidades de tratamento de superfície, com o intuito de melhorar o desempenho clínico dos pinos fibrorresinosos...


Since their introduction, fiber posts have been used for restoration of endodontically treated teeth. Despite the development of adhesive techniques in recent years, several studies have shown a significant percentage of adhesive failures at the post/resin cement interface. Thus, the present review addresses different clinical protocols suggested in the literature and new possibilities of surface treatments to improve the clinical performance of fiber posts...


Assuntos
Humanos , Pinos Dentários , Adesivos Dentinários , Cimentos de Resina , Dente não Vital
13.
J Dent ; 38(10): 802-10, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20599465

RESUMO

OBJECTIVES: To evaluate the dentin bond durability of simplified adhesives after one-year (1 y) under water storage and simulated pulpal pressure. METHODS: Class I cavities were prepared in sixty human third molars with the pulpal wall located in mid-coronal dentin. The roots were cut off to expose the pulpal chamber, and the teeth were assembled in a pulpal pressure simulator device. A two-step etch-and-rinse adhesive (Single Bond 2/SB), a two-step self-etch adhesive (Clearfil SE Bond/CSE), a three-step self-etch adhesive (Adper Scotchbond SE/SSE) and three all-in-one adhesives (Adper Easy Bond/EB, Clearfil S(3) Bond/S3 and Adhese One/AO) were applied according to manufacturers instructions. No enamel pre-etching was used for the self-etch systems. The cavities were filled with a composite (Z250, 3M ESPE) in four to five horizontal increments and individually cured. Immediately after the final cure, pulpal pressure was set to 15 cm H(2)O. After 24 h and 1 y under simulate pulpal pressure the teeth were cut following a 'nontrimming' microtensile test technique (n=30) and tested in tension. Kruskall-Wallis and post hoc multiple comparisons were used at alpha=0.05. Weibull statistics was applied to SB, CSE and EB. Fractographic analysis of debonded specimens was performed using scanning electron microscopy. RESULTS: At 24 h and 1 y periods, SB showed higher bond strength means than all the others adhesives tested. CSE was not statistically different from EB at 24 h and from EB and SB at 1 y. EB showed bond strength statistically higher than the other three self-etch adhesives, which were not statistically different from each other at 24 h. AO showed significantly lower bond strength than all tested materials after 1 y. For all adhesives the mean bond strength at 1 y were not statistically different from the values measured at 24 h (p>0.05). Shifts in failure mode patterns and Weibull modulus decrease indicate some degree of bond degradation after the 1 y storage period. CONCLUSION: One-year of simulated pulpal pressure did not affect dentin bond strength of simplified adhesives in Class I restorations. Signs of degradation were only revealed by fractographic analysis and reliability parameters.


Assuntos
Polpa Dentária/fisiologia , Adesivos Dentinários/química , Dentina/ultraestrutura , Cura Luminosa de Adesivos Dentários , Resinas Acrílicas/química , Bis-Fenol A-Glicidil Metacrilato/química , Fenômenos Químicos , Resinas Compostas/química , Preparo da Cavidade Dentária/métodos , Restauração Dentária Permanente/métodos , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Pressão , Cimentos de Resina/química , Estresse Mecânico , Propriedades de Superfície , Resistência à Tração , Fatores de Tempo , Água/química
14.
Gen Dent ; 58(4): 326-30, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20591778

RESUMO

This in vitro study evaluated the microtensile bond strength (muTBS) of composite resin bonded to dentin that had been contaminated by cigarette smoke. Ten extracted unerupted human third molars were used: Six molars were prepared for muTBS testing, while the other four molars were assigned to pre- and post-etching scanning electronic microscopy (SEM) analysis. The 20 specimens obtained from the 10 coronal portions were distributed into two experimental groups so that each tooth served as its own control. Group 1 underwent a daily toothbrushing simulation and exposure to a smoking simulation chamber, while Group 2 received only a daily simulated toothbrushing. Student's t-test demonstrated that Group 1 samples demonstrated significantly lower bond strength (49.58 MPa) than Group 2 samples (58.48 MPa). Pre and postetching SEM analysis revealed the presence of contaminants on the dentinal surfaces of the Group 1 specimens. It was concluded that contamination by cigarette smoke decreases the bond strength between dentin and composite resin.


Assuntos
Poluentes Atmosféricos/química , Resinas Compostas/química , Colagem Dentária/métodos , Adesivos Dentinários/química , Dentina/efeitos dos fármacos , Fumaça , Falha de Restauração Dentária , Análise do Estresse Dentário , Dentina/ultraestrutura , Humanos , Teste de Materiais , Dente Serotino , Fumar , Estatísticas não Paramétricas , Resistência à Tração/efeitos dos fármacos
15.
Oper Dent ; 35(2): 139-46, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20420056

RESUMO

OBJECTIVE: To evaluate the influence of various light sources on the microhardness of human dental enamel following treatment with an in-office vital bleaching agent (35% hydrogen peroxide). METHODS AND MATERIALS: One-hundred and sixty dental enamel slabs (-2.5 x 2.5 x 1.0 mm) were obtained from 32 recently extracted human third molars, polished and subjected to hardness testing (KHN, 50g-load, 5 seconds) after four time periods (baseline and after 1, 7 and 14 days). The specimens were placed in intraoral appliances and delivered to eight volunteers after being equally divided into five groups each according to the light source treatment to be performed extraorally (n=32): Group LA (35% hydrogen peroxide + argon laser unit); Group HA (35% hydrogen peroxide + halogen light-curing unit); Group LED (35% hydrogen peroxide + LED-laser unit); Group OX (35% hydrogen peroxide + no light source unit); or Group CO (control: saliva only). Microhardness values were analyzed by ANOVA and Tukey's post-hoc test (alpha = 0.05). RESULTS: Significant decreases in KHN were found in enamel for the HA group one day and seven days after treatment (5.81% and 2.35%, respectively) (p < 0.0001). However, no significant differences were found between the baseline and final microhardness values for all groups submitted to bleaching. CONCLUSION: The different tested light sources did not significantly influence the microhardness of human enamel following treatment with 35% hydrogen peroxide.


Assuntos
Lâmpadas de Polimerização Dentária , Esmalte Dentário/efeitos da radiação , Dureza/efeitos da radiação , Clareamento Dental , Adulto , Análise de Variância , Esmalte Dentário/efeitos dos fármacos , Halogênios , Dureza/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Lasers de Gás , Lasers Semicondutores , Luz , Pessoa de Meia-Idade , Dente Serotino , Oxidantes/farmacologia , Estatísticas não Paramétricas , Adulto Jovem
16.
Clín. int. j. braz. dent ; 6(1): 86-96, jan.-mar. 2010. ilus, graf, tab
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-716601

RESUMO

A tecnologia de planejamento e produção computadorizada de restaurações dentárias pode ser utilizada para as mais diferentes situações clínicas. Isso, associado ao grande número de empresas fabricantes de equipamentos para o conceito CAD/CAM, resultou em uma miríade de materiais restauradores para a confecção de peças protéticas sob esse conceito. O presente artigo, último de uma série de três, discute os materiais metálicos, resinosos e, principalmente, cerâmicos indicados para produção por sistemas CAD/CAM. Ênfase é dada ao dióxido de zircônio, por ser um material que apresenta características relevantes para a odontologia restauradora e ter, na tecnologia automatizada, um grande facilitador de seu processamento


The computerized technology for the design and production of dental restorations can be employed in many clinical situations. This broad range of indications, associated to a great number of equipment’s manufactures for the CAD/CAM concept resulted in a myriad of restorative materials suitable for the manufacturing of prosthetic elements. This article, last of a series of three, discusses the metallic, resinous and, ceramic materials that are by dental CAD/CAM systems. An emphasis is given to the zirconium dioxide, a ceramic that presents very interesting properties for restorative dentistry and is highly benefited by the computerized manufacturing technology


Assuntos
Desenho Assistido por Computador , Prótese Dentária , Restauração Dentária Permanente , Zircônio
17.
Clín. int. j. braz. dent ; 5(4): 424-435, out.-dez. 2009. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-716577

RESUMO

Os sistemas CAD/CAM atuais podem ser utilizados para a confecção de inúmeros tipos de peças protéticas, desde inlays e onlays até amplas pontes fixas de 14 elementos. O desenvolvimento das tecnologias e consequente aumento da utilização dos métodos de planejamento e produção computadorizados resultaram em grande número de sistemas no mercado. O presente artigo, segundo de uma série de três, discute as possibilidades restauradoras com o uso de sistemas CAD/CAM e apresenta os principais equipamentos existentes no cenário odontológico mundial.


The present CAD/CAM systems are capable to produce a number of indirect restorations, from inlays and onlays to larg-span 14-units bridges. The development of technologies and consequent increasing use of computerized design and manufacturing methods resulted in a great number of CAD/CAM systems in the market. This article, the second of a series of three, discusses the restorative possibilities using CAD/CAM technology and presents the main equipment’s and systems available in the world dental scenario.


Assuntos
Desenho Assistido por Computador , Equipamentos Odontológicos , Prótese Dentária , Restauração Dentária Permanente
18.
Clín. int. j. braz. dent ; 5(3): 294-303, jul.-set. 2009. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-716537

RESUMO

A odontologia restauradora atual vem sendo transformada pela utilização de sistemas automatizados. As fases de impressão, planejamento e confecção de diversos tipos de restaurações podem ser realizadas com o auxílio de técnicas e equipamentos computadorizados, no conceito de produção chamado de CAD/CAM. O presente artigo, que é o primeiro de uma série de três, discute os princípios desse conceito, aponta vantagens, limitações e pondera sobre algumas mudanças que tais tecnologias provocam no cotidiano dos profissionais da odontologia.


One of the latest advances in restorative dentistry is the use of computer-based techniques and equipment’s in several procedures, from restoration planning (designing), impression-taking, and fabrication of a number of dental restorations. This concept is called CAD / CAM. This is the first article of a series of three, addresses the fundamentals of CAD/CAM concept, points out the advantages and limitations, and discusses some changes that these technologies brings to dentistry’s daily practice.


Assuntos
Desenho Assistido por Computador , Prótese Dentária , Restauração Dentária Permanente
19.
Clín. int. j. braz. dent ; 5(3): 304-310, jul.-set. 2009.
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-716538

RESUMO

Embora os materiais de cimentação e as técnicas adesivas tenham evoluído nas últimas décadas, a adesão de pinos fibrorresinosos ainda é considerada um desafio. A presente revisão de literatura aponta os principais desafios e possibilidades dessa técnica e fornece subsídios científicos para se contornar os problemas envolvidos e auxiliar na tomada de decisão clínica.


Although luting materials and the adhesive techniques have evolved in the last few decades, adhesion to fiber-reinforced composite posts is still considered a challenge. The purpose of this literature review is to address and discuss the main challenges and possibilities of this technique and to supply scientific evidence to avoid the major problems and to support decision-making.


Assuntos
Cimentação , Adesivos Dentinários , Técnica para Retentor Intrarradicular
20.
Clín. int. j. braz. dent ; 5(1): 86-93, jan.-mar. 2009. ilus, tab, graf
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-547582

RESUMO

O propósito deste estudo é avaliar a influência do preparo cavitário (MO e MOD) e do término cervical (esmalte ou dentina) na adaptação marginal cervical de inlays cerâmicos (IPS Empress). Os resultados demonstram que não há diferença entre os grupos avaliados.


Assuntos
Cerâmica , Adaptação Marginal Dentária , Restaurações Intracoronárias
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...