Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Photobiomodul Photomed Laser Surg ; 40(12): 818-825, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36507769

RESUMO

Objective: to evaluate the bond strength of repairs to composite resin restorations treated with CO2 laser and bifunctional monomers after 1 year of aging. Background: Adequate bond strength between a composite restoration and resin repair agent can be achieved through mechanical and/or chemical treatment. However, the longevity of such repairs is unknown. Methods: Resin blocks (volume: 125 mm3) were created. Failure surfaces were either not treated or were treated before the repair with a universal adhesive, a silane bonding agent and/or CO2 laser. The blocks were distributed into six groups (n = 6 per group): resin+resin group (RRG), universal adhesive+resin group (ARG), silane+universal adhesive group (SAG), laser+silane+universal adhesive group (LSAG), laser+universal adhesive group (LAG), and laser+silane group (LSG). After treatment, repairs were made with another resin composite. "Sticks" (1.0 mm2 in area and 1.0 cm in length) were cut from the specimens in each group and immersed in distilled water at 37°C. Microtensile bond strength was evaluated after 1 year of aging. Bond strength values were compared using the Kruskal-Wallis test and Dunn's test. Results: Bond strength was significantly higher in the LSAG compared with the RRG, adhesive system, LSG, whereas statistically similar results were found for the SAG, LSAG, and LAG. Bond strength was lowest in the RRG. The LSAG and LAG presented predominantly cohesive fractures. Conclusions: The bond strength of composite resin repairs was satisfactory over time. Treatment with CO2 laser contributed to the maintenance of bond strength during the 1-year storage period and bifunctional monomers present in the universal adhesive on the irradiated repair surface were of fundamental importance to the maintenance of bond strength values, as demonstrated by microtensile bond test and fracture pattern analysis.


Assuntos
Resinas Compostas , Cimentos de Resina , Resinas Compostas/química , Cimentos de Resina/química , Dióxido de Carbono , Propriedades de Superfície , Teste de Materiais , Silanos/química
2.
Biomed Res Int ; 2022: 4293975, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36420095

RESUMO

Objective: To evaluate different concentrations of solvents (tetrahydrofuran (THF) and dimethyl sulfoxide (DMSO) and monomers on the degree of conversion, microtensile bond strength, and mechanical properties of experimental resin infiltrants. Materials and Methods: Resin infiltrants were formulated and divided into eleven groups: (1) Icon, (2) 75% TEGDMA (T) +25% UDMA (U), (3) T +25% BIS-EMA (B), (4) T + U +0.5%DMSO, (5) T + U +5% DMSO, (6) T + U +0.5% THF, (7) T + U +5% THF, (8) T + B +0.5% DMSO, (9) T + B +5% DMSO, (10) T + B +0.5% THF, and (11) T + B +5% THF. One hundred and ten bovine mandibular incisors were sectioned, treated, and destined to the degree of conversion, tensile cohesive strength, microtensile bond strength, flexural strength, and elastic modulus. Data were submitted to one-way ANOVA and Tukey's test (α = 0.05). Results: The degree of conversion was lowest for T + B +5%THF (41.9%) and highest for T + U +5%THF (62.1%). In flexural strength and E-modulus, the T + B (96.5 MPa and 0.49 GPa) obtained the highest values and the lowest for T + U +5% DMSO (18.5 MPa and 9.7 GPa). Icon showed the highest bond strength (19.3 MPa) and cohesive strength (62.2 MPa), while T + U +5%DMSO (9.7 MPa) and T + B +5% DMSO (9.8 MPa) the lowest values and T + B +0.5% DMSO (12.3 MPa) the lowest cohesive strength. Conclusions: The addition of lower concentrations of DMSO or THF (0.5%) did not impair bond strength or significantly affect monomer conversion, but reduced the mechanical properties of resin infiltration.


Assuntos
Resinas Compostas , Dimetil Sulfóxido , Bovinos , Animais , Solventes/química , Resinas Compostas/química , Teste de Materiais , Resistência à Tração
3.
Life (Basel) ; 12(7)2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35888053

RESUMO

The gold standard for the management of sleep bruxism (SB) is the use of a rigid occlusal splint; however, there are limitations for its use in children and alternatives to the management of SB are needed. Photobiomodulation therapy has been used with positive results in temporomandibular disorders. This study aimed to evaluate the effects of photobiomodulation therapy with infrared LED in children with SB. Thirty children were divided into three groups: Group 1: control/absence of bruxism (n = 10); Group 2: SB treated with infrared LED (n = 10); Group 3: SB treated with occlusal splint (n = 10). Electromyographic evaluation of masseter, anterior temporalis, and upper trapezius, and salivary dopamine levels were assessed before and after treatments. Data were statistically analyzed using two-way mixed model ANOVA. An increase in the temporalis and right masseter EMG activity at rest was observed in Group 3, with large effect size (p < 0.05). Left masseter and temporalis EMG activity did not differ over time in the LED group, similar to the control group. Moreover, the EMG activity of masticatory muscles during chewing and upper trapezius muscle did not differ over time in all groups. The results also pointed to a difference in the levels of dopamine between children with and without SB, with Group 3 showing higher levels in the pre-treatment time compared to controls (p < 0.025). In conclusion, an increase in the masticatory muscles activity at rest was observed in children undergoing splint therapy. Moreover, a difference in the levels of salivary dopamine was found between children with and without SB.

4.
Photobiomodul Photomed Laser Surg ; 39(6): 381-385, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34029114

RESUMO

Objective: The aim of this study was to analyze the microhardness of demineralized enamel following different treatments (fluoride varnish, Er:YAG laser, and Er:YAG laser associated with fluoride varnish). Methods: Forty-eight enamel blocks (4 × 4 × 7 mm) were divided into six groups (n = 8): (S) Sound; (DE) Demineralized; (DED) DE + Duraphat® 5% (fluoride varnish); (DEL20) DE + Er:YAG laser (20 mJ pulse mode; 0.20 W; 10 Hz; 60 sec; 1.18 J/cm2; 11.83 W/cm2); (DEL50) DE + Er:YAG laser (50 mJ pulse mode; 0.50 W; 10 Hz; 60 sec; 2.95 J/cm2; 29.58 W/cm2); (DEL20D) DE + Er:YAG laser (20 mJ) + Duraphat 5%. The irradiation was performed at 1 mm distance from the surface using a tip (AS7066X, L-14 mm, D-1.3 mm in diameter) in water/air spray refrigeration (level 6). The enamel blocks were submitted to pH cycling (4 h into DES solution +20 h into RE solution for 8 days and the solutions were changed every day). Knoop microhardness was measured (50 g/15 sec, six readings per sample) and data were analyzed by Kruskal-Wallis test at 5% significance. Results: After treatments, DF group showed higher microhardness values than all the groups. Also, DEL20D group showed similar results with H group according to the microhardness analysis (p < 0.05). Conclusions: It could be concluded that Duraphat 5% treatment showed better results when compared with all tested groups, however, the association of Er:YAG Laser 20 with Duraphat 5% also showed promising results.


Assuntos
Lasers de Estado Sólido
5.
Photobiomodul Photomed Laser Surg ; 39(1): 38-45, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33337926

RESUMO

Background: Orofacial pain has been a prevalent symptom in the worldwide population, which may cause restrictions in daily activities and, consequently, have a great impact on the well-being of affected individuals. Photobiomodulation using light sources, such as low-level laser or light emitting diodes, with different wavelengths, has been widely used in the last years, in addition to being a noninvasive, low-cost resource and reducing pain. Objective: This study aimed at evaluating the effect of photobiomodulation as a protocol treatment to prevent facial muscle discomfort after long-term clinical procedures. Methods: The volunteers were randomized and allocated as follows: laser (n = 16) and placebo (n = 16) groups, following a crossover study design. The laser parameters were as following: 786 nm wavelength, 9 J per point, and 100 mW power of 2.393 W/cm2 irradiance. The discomfort was induced by simulating a 50-min dental procedure (with bilateral mouth open), and the pain scale (assessed bilaterally), tiredness, and temperature measurement through thermography were used for analysis. Results: The results showed a significant lower pain and tiredness in the laser group. Also, the results showed a statistically significant valid temperature change between the groups at times: T1, T40, and T50. Conclusions: According to our results, photobiomodulation showed a positive effect on the face musculature in patients submitted to the treatments, reducing pain and improving the subjective perception of exertion.


Assuntos
Terapia com Luz de Baixa Intensidade , Estudos Cross-Over , Dor Facial , Humanos , Medição da Dor
6.
Photodiagnosis Photodyn Ther ; 29: 101655, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923635

RESUMO

The aim of this in vitro study was to evaluate the preventive effect of different materials on dental erosion lesions by speckle coherent light scattering analysis. Forty bovine teeth were divided in the following groups (n = 10): 1) DURA- Preventive Treatment with Fluoride Varnish (Duraphat, Colgate-Palmolive); 2) ELX- Preventive treatment with Elmex® Erosion Protection Toothpaste (GABA International AG, Therwil, Switzerland); 3) MP- Preventive treatment with MI Paste® (GC America); and 4) REG- Preventive Treatment with Regenerate Enamel Science™ (Unilever). For all groups, each sample was divided into 3 areas: non-treatment (control); preventive treatment + erosive challenge; non-treatment + erosive challenge. The erosive challenge was carried out using Sprite® Zero soft drink (pH 2.58). After the erosive challenge, the samples were evaluated by speckle coherent light scattering method in the eroded area compared to the sound area. The results showed that there was a statistically significant difference between eroded area with and without preventive treatment, however, there was no statistically significant difference among the different preventive materials tested.


Assuntos
Cariostáticos/farmacologia , Esmalte Dentário/efeitos dos fármacos , Imagem Óptica/métodos , Erosão Dentária/diagnóstico por imagem , Erosão Dentária/prevenção & controle , Cremes Dentais/farmacologia , Animais , Bovinos , Diaminas/farmacologia , Fluoretos/farmacologia , Fluoretos Tópicos/farmacologia , Técnicas In Vitro , Teste de Materiais , Fluoreto de Sódio/farmacologia , Propriedades de Superfície
7.
J Lasers Med Sci ; 10(4): 304-309, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31875123

RESUMO

Introduction: Microleakage has been reported to cause dentin hypersensitivity because of the passage of bacteria and their products through the restoration-tooth interface and is one of the main reasons for replacement of restorations. CO2 laser can be used for treatment of dentin hypersensitivity. Thus, this study aimed to evaluate in vitro the microleakage in composite restorations following surface pretreatment with acid etching and CO2 laser. Methods: Twelve human caries-free primary molars were selected. Class II cavities were prepared on occlusal mesial and occlusal distal surfaces. Specimens were randomly divided into four groups (n=6): Group 1 (G1) - 37% phosphoric acid gel etching + Beautiful-Bulk Restorative - Giomer (Shofu Inc); Group 2 (G2) - 37% phosphoric acid gel etching + SDR Bulk-Fill Flow (Dentsply); Group 3 (G3) - CO2 laser irradiation + Beautiful-Bulk Restorative - Giomer (Shofu Inc); Group 4 (G4) - CO2 laser irradiation + SDR Bulk-Fill Flow (Dentsply). Surfaces were restored with bonding agent (Natural Bond DE, DFL). Specimens were cut longitudinally and immersed in 0.5% methylene blue solution for 4 hours. Microleakage scores were assessed under a magnifying glass at x3,5 and qualitatively analyzed by scanning electron microscope (SEM). Data were analyzed using nonparametric Wilcoxon test (P < 0.05). Results: Scores prevailed between 0 and 2, however, no statistically significant difference was found among the groups (P = 0.05). Conclusion: It could be concluded that all composite resins bulk fill did not show significant difference among them regarding microleakage using either CO2 laser or 37% phosphoric acid etching.

8.
Medicine (Baltimore) ; 98(15): e15110, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30985667

RESUMO

BACKGROUND: Antimicrobial photodynamic therapy (aPDT) has been used for the treatment of dental caries. Papacarie is a gel composed of papain and chloramine employed for the partial removal of carious tissue, effective against bacteria, however, some studies report that this antibacterial action is not quite so evident. The aim of this study is to evaluate the clinical effect of aPDT on infected dentin in dental caries lesion in primary teeth. METHODS: Thirty-two primary molars with deep occlusal dental caries will be selected and divided in 2 groups: G1 - caries removal with a low-speed drill and G2 - application of aPDT with PapacarieMBlue. After treatment, all the teeth will be restored with glass ionomer cement and followed up clinically and radiographically, with evaluations at 3, 6, and 12 months. Dentin samples before and after treatment will be analyzed microbiologically. The data will be submitted to descriptive statistical analysis of the association between the categorical variables and both age and gender using the chi-square test and Fisher exact text. The Student t test and analysis of variance will be used for the comparison of mean signs and symptoms of reversible pulpitis. Pearson correlation coefficients will be calculated for the analysis of correlations among the continuous variables. DISCUSSION: Adding methylene blue dye to the formula of PapacarieMBlue might potentiate the antimicrobial action of aPDT and work more effectively on the infected dentin combined with a conservative, minimally invasive treatment. TRIAL REGISTRATION: NCT02734420 on 10 march 2016.


Assuntos
Anti-Infecciosos/uso terapêutico , Cárie Dentária/terapia , Azul de Metileno/uso terapêutico , Papaína/uso terapêutico , Fotoquimioterapia , Dente Decíduo , Criança , Protocolos Clínicos , Cárie Dentária/diagnóstico por imagem , Dentina/diagnóstico por imagem , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Dente Decíduo/diagnóstico por imagem
9.
Dent J (Basel) ; 7(1)2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30720710

RESUMO

This study aimed to evaluate microhardness of a dentifrice containing fluoride and arginine compared to a positive control (fluoride only) and a negative control (no fluoride) on sound and demineralized bovine enamel surfaces. Specimens were randomly assigned to different treatments that included daily pH cycling and brushing three times a day with one of the following dentifrices (n = 8): Neutraçucar (arginine and fluoride), Colgate Total 12 (fluoride) and My First Colgate (no fluoride). Enamel carious lesions were artificially created one week before the beginning of these treatments (demineralized bovine enamel (DE) groups). The same groups were also tested in sound enamel (sound bovine enamel (SE) groups). Microhardness was measured at baseline and after one, two, and five weeks of treatment using a Knoop indenter. Statistical analysis involved two-way Analysis of Variance (ANOVA) and Tukey's test. After five weeks, both Total 12 and Neutraçucar had increased the microhardness of DE specimens (p < 0.05). Only Neutraçucar had increased the microhardness of the sound enamel after five weeks of treatment. Thus, it could be concluded that arginine-based dentifrices increase the microhardness of sound and demineralized bovine enamel surfaces.

10.
Biomed Res Int ; 2018: 5852948, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30175135

RESUMO

OBJECTIVE: To evaluate the influence of ultrapulsed CO2 laser in combination with commercial fluoride products in order to verify the increase of microhardness of artificial enamel caries lesions. MATERIALS AND METHODS: Bovine enamel specimens were prepared, and artificial enamel caries lesions were created. Teeth were randomly divided into 5 groups (n=10): treated with laser (L), laser + neutral fluoride gel 2% (LNF), laser + acidulated phosphate fluoride gel 1.23% (LAFG), laser + acidulated fluoride mousse 1.23% (LAFM), and laser + fluoride varnish 5% (LFV). Microhardness was evaluated at baseline, after caries induction, after CO2 laser irradiation + fluoride treatment in the 1st week, and after fluoride treatment at 3rd and 5th week. RESULTS: There was a decrease in microhardness in all groups after artificial enamel caries lesion formation; no increase in microhardness was found in the first and third weeks in all groups (p > 0.05). In the fifth week, an increase in microhardness occurred in all groups (p < 0.05). CONCLUSION: Although CO2 laser irradiation in combination with different commercial fluoride products was capable of increasing microhardness on enamel caries lesions in bovine tooth enamel it is necessary to confirm these results by testing the isolated effect of fluoride on enamel surface microhardness. Also, although microhardness was higher in the fluoride varnish group than in the other groups in the fifth week it is not possible to discard the best effect of fluoride varnish treatment on absence of artifacts that may occur with the other fluoride treatments. CLINICAL RELEVANCE: In order to prove that CO2 laser may contribute to an increase in microhardness when applied to enamel lesions in combination with different commercial fluoride products it is necessary to conduct additional studies. Also, higher microhardness of fluoride varnish group should be carefully considered.


Assuntos
Esmalte Dentário , Fluoretos Tópicos , Lasers de Gás , Fluoreto de Fosfato Acidulado , Animais , Bovinos , Fluoretos , Distribuição Aleatória
11.
Photodiagnosis Photodyn Ther ; 18: 221-225, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28300725

RESUMO

BACKGROUND: This study presents the correlation between laser speckle images and detection of incipient caries lesions from changs in the microstructure of the surface of tooth enamel. METHODS: We used 30 healthy deciduous molar teeth collected from the Biobank Human Teeth, Faculty of Dentistry, University of São Paulo who had carious lesions induced by the pH cycling method. The samples were evaluated for the diagnosis of caries by two methods ICDAS and speckle pattern of coherent light scattering after 5, 10 and 15days and the results were statistically analyzed using α=0.05 significance level. RESULTS: A significant difference was observed between the image of the speckle scattering of healthy and injured areas within the 3 study groups, but not when comparing the three groups, showing us that it is an innovative technique that needs further study, but can be used as a diagnostic method for the detection of early caries lesions. CONCLUSION: It can be concluded that the analysis of scattering speckle pattern is a diagnostic technique that provides information on the microstructure of the surface of tooth enamel which has sensitivity for detection of incipient caries lesions.


Assuntos
Cárie Dentária/diagnóstico por imagem , Cárie Dentária/patologia , Interpretação de Imagem Assistida por Computador/métodos , Dente Molar/diagnóstico por imagem , Dente Molar/patologia , Fotografia Dentária/métodos , Dente Decíduo/diagnóstico por imagem , Testes de Atividade de Cárie Dentária , Feminino , Humanos , Técnicas In Vitro , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Dente Decíduo/patologia
12.
J Phys Ther Sci ; 29(12): 2107-2111, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29643585

RESUMO

[Purpose] Problems involving the temporomandibular joint and associated structures can lead to temporomandibular disorder (TMD). The aim of the present study was to evaluate muscle activity in individuals with a diagnosis of TMD before and after treatment with low-level laser therapy (LLLT) through the use of electromyography (EMG). [Subjects and Methods] Male and female individuals aged 14 to 23 years were evaluated. TMD was determined by a clinical examination and the administration of the Research Diagnostic Criteria for Temporomandibular Disorders, followed by the evaluation of sensitivity to palpation of the masseter and anterior temporal muscles as well as the EMG determination of muscle activity. The participants were randomly allocated to an active LLLT group (n=9) and sham group (n=7). Twelve sessions of LLLT were conducted using a wavelength of 780 nm, energy density of 25 J/cm2, power of 50 mW, power density of 1.25 W/cm2 and a 20-second exposure time or sham LLLT. Muscle activity was determined prior to treatment and after the last session. [Results] During the isometric evaluation of the masseter and anterior temporal muscles, an increase in the mean EMG signal was found in the group submitted to active LLLT. When evaluated individually, some participants in the active LLLT group demonstrated a reduction in muscle activity, but no significant differences were found in the mean EMG signal between the initial and final evaluations. [Conclusion] Further studies with a larger sample size are needed to confirm the present findings.

13.
Clin Oral Investig ; 21(6): 2143-2151, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27838844

RESUMO

OBJECTIVE: This study aimed at evaluating the chemophysical properties of experimental resin infiltrants (ERIs) doped with different bioactive particles. METHODS: A control resin infiltrant (CR) was formulated using triethylene glycol dimethacrylate (TEGDMA) and ethoxylated bisphenol A dimethacrylate (BisEMA). Moreover, five experimental ERIs were also created by incorporating the following bioactive fillers (10 wt%) into the CR: hydroxyapatite (Hap), amorphous calcium phosphate (ACP), zinc-polycarboxylated bioactive glass (BAG-Zn), bioactive glass 45S5 (BAG 45S5), and calcium silicate modified with beta tricalcium phosphate (ß-TCP). ICON® resin infiltrant was also used as control. All the ERIs used in this study were assessed for degree of conversion (DC), Knoop microhardness (KHN), softening ratio (SR), tensile cohesive strength (TCS), modulus of elasticity (E-modulus), water sorption (WS), and solubility (SL). Data were subjected to ANOVA and Tukey's test (α = 5%). RESULTS: ICON® presented the lowest DC, KHN, TCS, E-modulus, and SR. Incorporation of bioactive fillers into CR caused significant increase in the KHN. Conversely, no significant effect was observed on DC, TCS, and E-modulus. The resin infiltrant containing Hap showed a significant increase in softening ratio, while, ICON® presented the highest WS and SL. The WS of ACP-doped resin infiltrant was significantly higher than that of the Hap-doped infiltrant. The SL of the ACP-doped infiltrant was higher than CR BAG-Zn or BAG 45S5. CONCLUSION: The incorporation of bioactive particles into experimental resin infiltrants can improve the chemomechanical properties and reduce water sorption and solubility. CLINICAL RELEVANCE: Resin infiltrants doped with bioactive particles may improve the long-term performance of the treatment of white-spot lesions.


Assuntos
Materiais Dentários/química , Metacrilatos/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Resinas Sintéticas/química , Compostos de Cálcio/química , Fosfatos de Cálcio/química , Cerâmica/química , Durapatita/química , Módulo de Elasticidade , Vidro/química , Dureza , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Cimento de Policarboxilato/química , Silicatos/química , Solubilidade , Propriedades de Superfície , Resistência à Tração
14.
J Adhes Dent ; 17(2): 117-23, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25830164

RESUMO

PURPOSE: To evaluate the effect of different concentrations of monomers and solvents/diluents on the microtensile bond strength (µTBS) bond strength of experimental low-viscosity resins (infiltrants) to enamel caries-like lesions (ECLL). MATERIALS AND METHODS: Flat enamel blocks obtained from sound human third molars were submitted to ECLL formation and randomly distributed into 9 groups (n = 10): G1: TEG-DMA 100%; G2: TEG-DMA 80%, ethanol 20%; G3; TEG-DMA 80%, HEMA 20%; G4: TEG-DMA 75%, UDMA 25%; G5: TEG-DMA 60%, UDMA 20%, ethanol 20%; G6: TEG-DMA 60%, UDMA 20%, HEMA 20%; G7: TEG-DMA 75%, bis-EMA 25%; G8: TEG-DMA 60%, bis-EMA 20%, ethanol 20%; G9: TEG-DMA 60%, bis-EMA 20%, HEMA 20%. After etching with 37% phosphoric acid for 60 s, experimental infiltrants were actively applied and photocured for 60 s, then stored in 100% humidity (24 h, 37°C). Hourglass-shaped specimens were obtained and the µTBS test performed (MPa). The fracture patterns were assessed by SEM. Data were submitted to two way-ANOVA and Tukey's tests (α = 0.05). RESULTS: The highest µTBS value was observed for G4 (TEG-DMA/UDMA, 19.18 MPa) and the lowest for G5 (TEG-DMA/UDMA/ethanol, 9.00 MPa). A significant decrease in µTBS was observed for all groups containing ethanol (G2, G5, and G8). The addition of HEMA did not affect µTBS values. Most groups showed a high frequency of mixed failure between infiltrant and enamel. CONCLUSION: The addition of bis-EMA or UDMA to TEG-DMA-based infiltrants did not improve bond strength to carious enamel. The ethanol addition negatively affected the bonding strength of infiltrants to enamel caries-like lesions, regardless of the resin matrix composition of the infiltrant.


Assuntos
Resinas Compostas/química , Colagem Dentária , Cárie Dentária/patologia , Esmalte Dentário/ultraestrutura , Materiais Dentários/química , Solventes/química , Condicionamento Ácido do Dente/métodos , Análise do Estresse Dentário/instrumentação , Etanol/química , Humanos , Umidade , Teste de Materiais , Metacrilatos/química , Microscopia Eletrônica de Varredura , Ácidos Fosfóricos/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Poliuretanos/química , Estresse Mecânico , Propriedades de Superfície , Temperatura , Resistência à Tração , Fatores de Tempo
15.
J Dent ; 41(11): 1014-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24004967

RESUMO

OBJECTIVES: To evaluate the properties of experimental infiltrant blends by comparing them with the commercial infiltrant Icon(®) and penetration homogeneity into enamel caries lesions. METHODS: Groups were set up as follows: G1 (TEGDMA 100%); G2 (TEGDMA 80%, Ethanol 20%); G3 (TEGDMA 80%, HEMA 20%); G4 (TEGDMA 75%, BisEMA 25%); G5 (TEGDMA 60%, BisEMA 20%, Ethanol 20%); G6 (TEGDMA 60%, BisEMA 20%, HEMA 20%); G7 (TEGDMA 75%, UDMA 25%); G8 (TEGDMA 60%, UDMA 20%, Ethanol 20%); G9 (TEGDMA 60%, UDMA 20%, HEMA 20%) and Icon(®). Ten specimens were comprised by each group for the following tests (n=10): degree of conversion (DC), elastic modulus (EM), Knoop hardness (KH), and softening ratio (SR). Infiltrant penetration was evaluated using confocal microscopy (CLSM). Data were subjected to two-way ANOVA and a Tukey's test (5%). Data comparing experimental materials and Icon(®) were analysed using ANOVA and Dunnett's test (5%). RESULTS: The highest DC values were found in G1, G7, G8, and G9. The lowest DC values were found in G2, G4, G5, and G6. EM and KHN were significantly lower in HEMA and with ethanol addition for all blends, except for G9. There was no significant difference among the groups regarding SR, and it was not possible to take KHN readings of G2, G5, and G8 after storage. There was no significant difference among groups for infiltrant penetration into enamel lesions. CONCLUSIONS: The addition of hydrophobic monomers and solvents into TEGDMA blends affected DC, EM, and KHN. UDMA added to TEGDMA resulted in an increase in DC, EM, and KHN. Overall, solvents added to monomer blends resulted in decreased properties. The addition of hydrophobic monomers and solvents into TEGDMA blends does not improve the penetration depth of the infiltrants.


Assuntos
Resinas Compostas/química , Cárie Dentária/patologia , Esmalte Dentário/ultraestrutura , Materiais Dentários/química , Adsorção , Módulo de Elasticidade , Etanol/química , Dureza , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Metacrilatos/química , Microscopia Confocal , Polietilenoglicóis/química , Polimerização , Ácidos Polimetacrílicos/química , Poliuretanos/química , Resinas Sintéticas/química , Solventes/química , Propriedades de Superfície
16.
Eur J Dent ; 3(4): 290-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19826601

RESUMO

OBJECTIVES: The aim of this study was to evaluate the bond strength of one-step adhesive systems to dry or moist dental substrate. METHODS: Thirty human third molars were sectioned into two halves, in the mesio-distal direction, parallel to the long axis of the tooth. Each half was embedded in a polystyrene resin cylinder so that the buccal/lingual surface remained exposed. This exposed surface was abraded to obtain both flat exposed enamel and dentin. The samples were randomly allocated according to the adhesive system (Xeno III, Adper Prompt and iBond) and moisture condition (dry and moist). The substrates were air-dried for 30 s for dry condition, while the moist substrates were re-wet with 2.5 mul of distilled water after drying. After the adhesive procedures, two resin composite cylinders were build-up on dentin and enamel substrates, totaling four per sample. A shear load was applied to the samples at a crosshead speed of 0.5 mm/min until failure. Data were statistically analyzed by three-way ANOVA and the Tukey test (alpha=0.05). RESULTS: The evaluated one-step adhesives showed higher bond strength to dentin than enamel. The iBond presented better bond performance to moist substrate and Xeno III to dry substrate. The moisture condition did not interfere in the performance of Adper Prompt. The Xeno III and iBond presented higher bond strength than the other adhesives to both dry and moist substrates. CONCLUSIONS: The moisture condition of substrate interfered in the performance of one-step self-etching adhesives and the best moisture condition was material dependent.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...