Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
An Bras Dermatol ; 94(3): 279-286, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365655

RESUMO

BACKGROUND: Exposure to UVR provides benefits related to vitamin D synthesis, but also causes harms, since UVB is considered a complete carcinogen. There is no definition of the level of sun exposure and the proportion of exposed body required for proper synthesis of vitamin D in the skin without causing it damage. OBJECTIVES: This study aims to analyze the sun exposure index, vitamin D levels and clinical changes in the skin caused by constant sun exposure in the fishermen population. METHODS: It is a cross-sectional, observational and analytical study. The sample consisted of fishermen and was calculated in 174 individuals. The questionnaire was applied, the dermatological examination was carried out and the examinations of calcidiol, parathyroid hormone, calcium and phosphorus were requested. Data were expressed as percentages. The comparative analysis was done through the Chi-square test, and the correlations were established through the Pearson's linear coefficient. Results: We observed that there was vitamin D deficiency in a small part of the cases (11.46%), and the frequency of diagnosis of skin cancer was 2.7% of the cases surveyed. STUDY LIMITATIONS: The difficulty in categorizing the sun exposure index. CONCLUSION: The fact that fishermen expose themselves to the sun chronically and have been exposed to the sun for more than 15 years, between 21 and 28 hours a week, and without photoprotection, were indicative factors for protection against vitamin D deficiency. Chronic exposure to sun and high vitamin levels D may be indicative of protection of this population against skin cancer.


Assuntos
Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Luz Solar , Raios Ultravioleta , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina D/reabilitação , Vitamina D/biossíntese , Adulto , Índice de Massa Corporal , Brasil/epidemiologia , Estudos Transversais , Dieta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Inquéritos e Questionários , Vitamina D/sangue
2.
An. bras. dermatol ; 94(3): 279-286, May-June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1011121

RESUMO

Abstract: Background: Exposure to UVR provides benefits related to vitamin D synthesis, but also causes harms, since UVB is considered a complete carcinogen. There is no definition of the level of sun exposure and the proportion of exposed body required for proper synthesis of vitamin D in the skin without causing it damage. Objectives: This study aims to analyze the sun exposure index, vitamin D levels and clinical changes in the skin caused by constant sun exposure in the fishermen population. Methods: It is a cross-sectional, observational and analytical study. The sample consisted of fishermen and was calculated in 174 individuals. The questionnaire was applied, the dermatological examination was carried out and the examinations of calcidiol, parathyroid hormone, calcium and phosphorus were requested. Data were expressed as percentages. The comparative analysis was done through the Chi-square test, and the correlations were established through the Pearson's linear coefficient. Results: We observed that there was vitamin D deficiency in a small part of the cases (11.46%), and the frequency of diagnosis of skin cancer was 2.7% of the cases surveyed. Study Limitations: The difficulty in categorizing the sun exposure index. Conclusion: The fact that fishermen expose themselves to the sun chronically and have been exposed to the sun for more than 15 years, between 21 and 28 hours a week, and without photoprotection, were indicative factors for protection against vitamin D deficiency. Chronic exposure to sun and high vitamin levels D may be indicative of protection of this population against skin cancer.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/epidemiologia , Luz Solar , Raios Ultravioleta , Vitamina D/biossíntese , Deficiência de Vitamina D/reabilitação , Deficiência de Vitamina D/epidemiologia , Vitamina D/sangue , Brasil/epidemiologia , Índice de Massa Corporal , Estado Nutricional , Estudos Transversais , Inquéritos e Questionários , Dieta
3.
Pesqui. bras. odontopediatria clín. integr ; 19(1): 4107, 01 Fevereiro 2019. tab
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-997911

RESUMO

Objective: To evaluate the influence of gustatory stimuli on the buffering capacity of saliva. Material and Methods: The buccal ph of 18 male volunteers aged 18-35 years was measured after a mouthwash with 20 ml of water as a control, and in individual disposable cups they collected the saliva for two minutes. Then, each of chewed bubble gum with sugar for two minutes, discarding the gum and made new collection of saliva, for two minutes in other disposable cups individualized. After collection, each volunteer was again subject to regular brushing with toothpaste and waited another ten minutes. The same procedure was repeated with all other substances. Salivary buffer capacity was determined by Ericsson technique. Data were submitted to analysis of variance and the means were compared by the Scott-Knott grouping test and Mann-Whitney test at 5% probability. Estimates of Pearson correlations were calculated in order to determine possible associations between the variables. Results: It was not found statistically significant differences between the initial pH variation and after eating food (p>0.05), or between gustatory stimulation and variation of salivary buffer capacity (p>0.05). Conclusion: There is no influence of gustatory stimulus aroma and flavor on the variation of salivary buffer capacity.


Assuntos
Humanos , Masculino , Adolescente , Adulto , Saliva/metabolismo , Papilas Gustativas , Dieta , Percepção Gustatória , Concentração de Íons de Hidrogênio , Salivação , Brasil , Tampões (Química) , Análise de Variância , Estatísticas não Paramétricas
4.
Rev. CEFAC ; 20(4): 515-531, July-Aug. 2018. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-956515

RESUMO

ABSTRACT Purpose: to analyze the association of self-reported vocal symptoms with personal, occupational and clinical aspects and relate them to the quality of life of teachers/professors of the federal network of vocational and technological education. Methods: study carried out with 157 teachers from a federal public institution of vocational and technological education, who answered the World Health Organization Quality of Life questionnaire (WHOQOL-bref), Quality of Life in the Voice (V-RQOL) questionnaire and a data form (on social information, health conditions, vocal symptoms, habits, organization and working environment). Statistical analysis was performed using the Chi-square test. Results: 29% of the teachers presented vocal symptoms. The prevalent complaints were dry throat (38.2%), cough (37.6%) and hoarseness (30.6%). There was a higher prevalence of symptoms in females. For the WHOQOL-bref, the average was 71.3 points, which is considered regular. The domain with the highest score was the psychological one with 75.3. Regarding V-RQOL, the average score in the global domain was 92.5 points, and the physical score was the most compromised one. 90.5% of teachers showed low voice impact on quality of life. Conclusion: although these teachers present vocal complaints, they do not reflect in the limitation of the quality of life.


RESUMO Objetivo: analisar a associação de sintomas vocais autorreferidos com aspectos pessoais, ocupacionais, clínicos e relacionar com a qualidade de vida de professores da rede federal de ensino profissional e tecnológico. Métodos: estudo com 157 docentes de uma instituição pública federal de educação profissional e tecnológica, que responderam aos questionários World Health Organization Quality Of Life/bref (WHOQOL-bref), Qualidade de Vida em Voz (QVV) e o formulário de dados (sociais, condições de saúde, sintomas vocais, hábitos, organização e ambiente de trabalho). A análise estatística foi realizada por meio do teste Qui-quadrado. Resultados: 29% dos professores apresentaram sintomas vocais. As queixas prevalentes foram garganta seca (38,2%), tosse (37,6%) e rouquidão (30,6%). Houve maior prevalência dos sintomas no sexo feminino. Para o WHOQOL-bref, a média foi 71,3 pontos, considerada regular. O domínio com maior pontuação foi o psicológico com 75,3. Quanto ao QVV, o escore médio no domínio global foi de 92,5 pontos, sendo o físico o mais comprometido. 90,5% dos docentes apresentaram baixo impacto da voz na qualidade de vida. Conclusão: embora os docentes apresentem queixas vocais, elas não se refletem na limitação da qualidade de vida.

5.
Prótesenews ; 5(1): 18-30, jan.-mar. 2018. ilus
Artigo em Português | BBO - Odontologia | ID: biblio-906300

RESUMO

Os avanços na tecnologia dos materiais odontológicos têm permitido o desenvolvimento de técnicas mais conservadoras e aumentaram as chances de obter resultados estéticos mais previsíveis. Considerando as particularidades de cada técnica, a cerâmica tem sido usada devido à sua biocompatibilidade, longevidade e semelhança com a aparência natural do dente. O objetivo deste trabalho foi utilizar uma técnica minimamente invasiva previsível tanto esteticamente quanto funcionalmente para a confecção de dez laminados cerâmicos. Foi possível concluir que a proposta deste trabalho cumpriu com os requisitos para que uma reabilitação seja adequada nos quesitos de estética, função e estabilidade em longo prazo.


Technology advances in dental materials has allowed the development of more conservative techniques and increased the chances of more predictable aesthetics results. Considering the particularities of each technique, ceramics have been used due to its biocompatibility, longevity and likeness with the tooth natural appearance. The aim of this study was to use a predictable minimally invasive technique both aesthetically and functionally to fabricate 10 ceramic laminate veneers. It was concluded that the proposed technique in this work met the requirements for an esthetic, functional, and stable long-term rehabilitation.


Assuntos
Humanos , Feminino , Adulto , Cimentação , Porcelana Dentária , Planejamento de Prótese Dentária , Estética Dentária , Facetas Dentárias
6.
Pesqui. bras. odontopediatria clín. integr ; 16(1): 69-78, jan.-dez. 2016. ilus, tab
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-911084

RESUMO

Objective: To evaluate the impact of tooth loss on the quality of life of patients at the Cesmac University Center. Material and Methods: A cross-sectional study was performed, whose sample was composed of 224 volunteers from various health units of the selected health service with at least 12 years of age and one missing tooth. Quality of Life (QOL) was assessed using the Oral Health Impact Profile (OHIP -14) and tooth loss was assessed with the dental chart. A structured interview that assessed the socio-economic condition of the individual was also applied. For interpretation of the OHIP-14, values were assigned using the multiplicative method: 0-3 points = no impact; 3.01 to 6 points = low impact; 6.01 to 10 points = moderate impact; and> 10.01 points = high impact. All volunteers received guidance on oral health and, when necessary, a referral to the dental care provided by this institution was performed. Results: The mean OHIP ranged from no impact (30.9%) to high impact (27.8%). The correlation between the number of missing teeth and QOL scores was statistically significant (p <0.05), as well as the correlation between number of missing teeth and age of volunteers (p <0.0001). The dimensions of the OHIP-14 that showed the most influenced domains were pain, psychological discomfort, psychological disability. Conclusion: Increasing age has shown influence on tooth and tooth loss affected the QOL of volunteers. QOL may be influenced by other factors such as loss of anterior teeth and schooling.


Assuntos
Humanos , Masculino , Feminino , Criança , Assistência Odontológica , Saúde Bucal , Qualidade de Vida/psicologia , Perda de Dente , Brasil , Estatísticas não Paramétricas , Inquéritos e Questionários
7.
J Adhes Dent ; 14(6): 507-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23240109

RESUMO

PURPOSE: To evaluate the effect of different cleaning media on the adhesion of resin cement to feldspathic ceramic after etching. MATERIALS AND METHODS: The cementation surfaces of ceramic blocks (N = 20, n = 5 per group) were etched with 10% hydrofluoric acid (HF) gel for 20 s and rinsed for 60 s. They were then randomly assigned to 4 groups: G1: air-water spray+drying (control); G2: ultrasonic cleaning in distilled water for 4 min+drying; G3: ultrasonic cleaning in 99.5% acetone for 4 min+drying; G4: ultrasonic cleaning in 70% alcohol for 4 min+drying. The ceramic blocks were silanized and cemented (RelyX ARC) to the composite blocks. Subsequently, the microtensile bond strength test (µTBS) was performed. In addition, EDS analysis was made to assess the elemental composition of the conditioned and cleaned ceramic surfaces. RESULTS: A significantly higher mean µTBS was obtained when specimens had been ultrasonically cleaned in distilled water (G2: 18.8 ± 0.4 MPa) (p < 0.05) compared to other groups (G1: 16.6 ± 0.5; G3: 16.1 ± 0.9; G4: 15.8 ± 1.4) (one-way ANOVA). EDS analysis indicated the presence of F- only in G1. Dissolved precipitates after HF etching were removed by ultrasonic cleaning. CONCLUSION: Cleaning the HF-etched ceramic surface ultrasonically in distilled water is recommended, instead of rinsing it with air-water spray only.


Assuntos
Colagem Dentária , Porcelana Dentária , Detergentes , Cimentos de Resina , Ultrassom , Condicionamento Ácido do Dente , Adesividade , Análise do Estresse Dentário , Distribuição Aleatória , Resistência à Tração , Água
8.
São José dos Campos; s.n; 2011. 103 p. ilus, tab, graf.
Tese em Português | LILACS, BBO - Odontologia | ID: lil-642725

RESUMO

O objetivo deste trabalho foi avaliar o efeito de diferentes tratamentos de superfície da cerâmica Y-TZP na resistência de união, durabilidade e discrepância marginal. Para os testes de resistência adesiva, foram obtidos 144 corpos de prova (cp) da cerâmica VITA In-Ceram YZ for InLab (5,25 x 3,75 x 4,5 mm), que foram divididos em 6 grupos (G) (n=24), conforme o tratamento de superfície: G1: sem tratamento (controle); G2: jateamento com partículas de alumínio revestidas por sílica (CoJet®-Sand, 3M ESPE AG) (silicatização); G3: vitrificação 1 (Glaze Spray VITA AKZENT), condicionamento com ácido fluorídrico (HF) (1 min); G4: vitrificação 1 (Glaze Spray VITA AKZENT), silicatização; G5: vitrificação 2 (Glaze VITA AKZENT), condicionamento com HF (1 min); G6: vitrificação 2 (Glaze VITA AKZENT), silicatização. Após todos os tratamentos, as superfícies foram silanizadas por 5 min (ESPE-SIL) e a cimentação com Panavia F (Kuraray) foi realizada. Metade dos espécimes de cada tratamento foi ensaiada 24h após cimentação (SECO), a outra metade foi submetida à armazenagem (150 dias) e termociclagem (12.000x) (TC), e então realizado o ensaio de cisalhamento (1 mm/min). G7: G1+TC; G8: G2+TC; G9: G3+TC; G10: G4+TC; G11: G5+TC; G12: G6+TC. Superfícies tratadas foram analisadas por perfilometria óptica 3D para obtenção dos dados de rugosidade (Ra) e microscopia eletrônica de varredura (MEV) (1000x). Análise por energia dispersiva de raio-X (EDS) foi realizada para determinar os elementos químicos presentes na superfície de cada grupo. Para a análise de adaptação marginal foram confeccionadas 60 infraestruturas (adaptadas em um troquel metálico) nas quais foram realizados os mesmos tratamentos de superfície. Os dados obtidos foram analisados estatisticamente. Constata-se que tanto na condição Seco como na condição TC os grupos que receberam tratamento de superfície via vitrificação (vitrificação 1 e vitrificação 2) apresentaram mais alta resistência de união comparada ao grupo...


The aim of this study was to evaluate the effect of different surface treatments of Y-TZP ceramic on bond durability and marginal fit. 144 specimens of VITA In-Ceram YZ for InLab ceramic (5.25 x 3.75 x 4.5 mm) were obtained and divided into 6 groups (n=24) according to the surface treatment: G1: no treatment (control); G2: chairside tribochemical silica coating system (CoJet®-Sand, 3M ESPE AG) (Cojet); G3: vitrification 1 (Glaze Spray VITA AKZENT), conditioning with hydrofluoric acid (HF) (1 minute); G4: vitrification 1 (Glaze Spray VITA AKZENT), Cojet; G5: vitrification 2 (Glaze VITA AKZENT), conditioning with HF (1 minute); G6: vitification 2 (Glaze VITA AKZENT), Cojet. Then, the ceramic surfaces were silanized and the cement Panavia F (Kuraray) was applied. Half of the specimens from each treatment was tested 24 hours after cementation (DRY), the remaining specimens were stored in distilled water for150 days, thermocycled(12,000x) (AGING) and then the shear test was performed (1mm/minute). Conditioned surfaces were evaluated by 3D optical profilometry in order to obtain roughness data (Ra) and analysed by scan electronic microscopy (SEM) (1000x). Analysis by energy x-ray dispersive (EDS) was performed to determine the chemical elements present in each surface group. For analysis of marginal adaptation 60 crowns were produced (adapted into a metal die) and the same surface treatments were carried out on the internal surface of the crowns. The data were analysed using. The results suggest the vitrification 1 and vitrification 2 groups showed the highest bond strength compared to the control group. The highest marginal discrepancies were observed in the vitrification groups (117.36±29.61 to 105.78±12.23) comparing with the other groups (55.29±8.71 and 55.04±8.55). The proposed new surface treatment changed the Y-TZP ceramic morphology improving its adhesion to the resin cement...


Assuntos
Adesão Celular , Cerâmica , Vitrificação , Abrasão Dental por Ar
9.
Dent Traumatol ; 25(6): 578-83, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19788428

RESUMO

A high prevalence of dental trauma exists and its effects on function and esthetics deserve the attention of general dentists. The aim of this study was to assess the level of general dental practitioners' (GDPs) knowledge about guidelines for dental avulsion and its prevention using a questionnaire. The 21-item questionnaire was distributed among 264 GDPs and the survey was realized between August-November 2006. The data obtained were statistically analyzed using descriptive analysis and Pearson's Chi-square test to determine associations between knowledge regarding emergency treatment and dentists from public or private dental schools and years of experience. The results showed that the participants exhibited appropriate knowledge concerning procedures in cases of tooth avulsion and its prevention. The number of correct answers was low in relation to recommended treatment at the site of injury. Storage medium, preparation of the alveolus and splint time for receiving the avulsed tooth received a high number of correct answers. One statistically significant association between years of experience and recommended treatment at the site of the injury in the case an avulsed tooth (chi(2) = 9.384, P = 0.009). In conclusion, this survey showed appropriate knowledge of dental avulsion management and its prevention among the surveyed dentists. The findings also showed that communication between dentists and the population is deficient, especially concerning practitioners of high risk and contact sports.


Assuntos
Odontologia Geral , Conhecimentos, Atitudes e Prática em Saúde , Avulsão Dentária/terapia , Adulto , Competência Clínica , Tratamento de Emergência , Feminino , Humanos , Masculino , Soluções para Preservação de Órgãos , Contenções Periodontais , Cuidados Pós-Operatórios , Guias de Prática Clínica como Assunto , Inquéritos e Questionários , Avulsão Dentária/prevenção & controle , Reimplante Dentário
10.
Ciênc. odontol. bras ; 11(02): 29-35, abr-jun. 2008. tab
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-850633

RESUMO

O presente estudo avaliou a resistência da união entre a superfície da cerâmica VITA OMEGA 900 (VITA) e dois cimentos resinosos. Foram confeccionados quatorze blocos da cerâmica com dimensões de 6mm x 6mm x 5mm (recomendações do fabricante), os quais foram duplicados em resina composta (W3D MASTER, Wilcos, Brasil). Uma das faces de cada bloco cerâmico (6mm x 5mm) foi tratada com ácido fluorídrico a 10% (Dentsply) e cimentada com dois diferentes cimentos resinosos: Panavia F (Kuraray) and Rely X (3M/ESPE) sob carga constante de 750g, à face do bloco de resina composta correspondente. Os conjuntos cerâmica-cimento-resina composta foram divididos em. dois grupos (n=7): grupo do Panavia F e grupo do Rely X. Cada conjunto foi cortado e foram obtidas oito amostra por conjunto. Cada uma foi fixada com cianoacrilato em um paquímetro adaptado e acoplado em máquina de ensaios universal (EMIC) com velocidade de 0,5mm/min. Os dados (MPa) foram submetidos ao teste estatístico paramétrico ” t ”de amostras independentes cujos resultados indicaram que o grupo do Panavia F (média = 16,07 MPa ; dp = 3,61) não diferiu estatisticamente (t= 1,27; gl=12; p-valor = 0,228) do grupo do RelyX (média = 13, 71 ; dp = 3.33) ao nível de significância de 5%. De acordo com os resultados obtidos foi possível concluir que os dois cimentos resinosos usados nesse estudo foram eficientes para cimentação intra-oral.


Assuntos
Cimentos de Resina , Resistência à Tração
11.
J Prosthet Dent ; 100(2): 107-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18672127

RESUMO

STATEMENT OF PROBLEM: The use of ultrasonic tips has become an alternative for cavity preparation. However, there are concerns about this type of device, particularly with respect to intrapulpal temperatures and cavity preparation time. PURPOSE: The purpose of this study was to analyze pulpal temperature increases generated by an ultrasonic cavity preparation with chemical vapor deposition (CVD) tips, in comparison to preparation with a high-speed handpiece with a diamond rotary cutting instrument. The time required to complete the cavity preparation with each system was also evaluated. MATERIAL AND METHODS: Thermocouples were positioned in the pulp chamber of 20 extracted human third molars. Slot-type cavities (3 x 3 x 2 mm) were prepared on the buccal and the lingual surfaces of each tooth. The test groups were: high-speed cavity preparation with diamond rotary cutting instruments (n=20) and ultrasonic cavity preparation with CVD points (n=20). During cavity preparation, the increases in pulpal temperature, and the time required for the preparation, were recorded and analyzed by Student's t test for paired samples (alpha=.05). RESULTS: The average pulpal temperature increases were 4.3 degrees C for the high-speed preparation and 3.8 degrees C for the ultrasonic preparation, which were statistically similar (P=.052). However, significant differences were found (P<.001) for the time expended (3.3 minutes for the high-speed bur and 13.77 minutes for the ultrasound device). CONCLUSIONS: The intrapulpal temperatures produced during cavity preparation by ultrasonic tips versus high-speed bur preparation were similar. However, the use of the ultrasonic device required 4 times longer for the completion of a cavity preparation.


Assuntos
Preparo da Cavidade Dentária/instrumentação , Equipamentos Odontológicos de Alta Rotação , Polpa Dentária/fisiologia , Ultrassom , Temperatura Corporal , Preparo da Cavidade Dentária/métodos , Diamante , Humanos , Fatores de Tempo
12.
Ciênc. odontol. bras ; 11(2): 29-35, abr.-jun. 2008. tab
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-524128

RESUMO

O presente estudo avaliou a resistência da união entre a superfície da cerâmica VITA OMEGA 900 (VITA) e dois cimentos resinosos. Foram confeccionados quatorze blocos da cerâmica com dimensões de 6mm x 6mm x 5mm (recomendações do fabricante), os quais foram duplicados em resina composta (W3D MASTER, Wilcos, Brasil). Uma das faces de cada bloco cerâmico (6mm x 5mm) foi tratada com ácido fluorídrico a 10% (Dentsply) e cimentada com dois diferentes cimentos resinosos: Panavia F (Kuraray) and Rely X (3M/ESPE) sob carga constante de 750g, à face do bloco de resina composta correspondente. Os conjuntos cerâmica-cimento-resina composta foram divididos em. dois grupos (n=7): grupo do Panavia F e grupo do Rely X. Cada conjunto foi cortado e foram obtidas oito amostra por conjunto. Cada uma foi fixada com cianoacrilato em um paquímetro adaptado e acoplado em máquina de ensaios universal (EMIC) com velocidade de 0,5mm/min. Os dados (MPa) foram submetidos ao teste estatístico paramétrico ” t ”de amostras independentes cujos resultados indicaram que o grupo do Panavia F (média = 16,07 MPa ; dp = 3,61) não diferiu estatisticamente (t= 1,27; gl=12; p-valor = 0,228) do grupo do RelyX (média = 13, 71 ; dp = 3.33) ao nível de significância de 5%. De acordo com os resultados obtidos foi possível concluir que os dois cimentos resinosos usados nesse estudo foram eficientes para cimentação intra-oral.


Assuntos
Cimentos de Resina , Resistência à Tração
14.
J Adhes Dent ; 9(5): 443-7, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18297825

RESUMO

PURPOSE: This study evaluated the effect of surface conditioning methods and thermocycling on the bond strength between a resin composite and an indirect composite system in order to test the repair bond strength. MATERIALS AND METHODS: Eighteen blocks (5 x 5 x 4 mm) of indirect resin composite (Sinfony) were fabricated according to the manufacturer's instructions. The specimens were randomly assigned to one of the following two treatment conditions (9 blocks per treatment): (1) 10% hydrofluoric acid (HF) for 90s (Dentsply) + silanization, (2) silica coating with 30-im SiOx particles (CoJet) + silanization. After surface conditioning, the bonding agent was applied (Adper Single Bond) and light polymerized. The composite resin (W3D Master) was condensed and polymerized incrementally to form a block. Following storage in distilled water at 37 degrees C for 24 h, the indirect composite/resin blocks were sectioned in two axes (x and y) with a diamond disk under coolant irrigation to obtain nontrimmed specimens (sticks) with approximately 0.6 mm2 of bonding area. Twelve specimens were obtained per block (N=216, n=108 sticks). The specimens from each repaired block were again randomly divided into 2 groups and tested either after storage in water for 24 h or thermocycling (6000 cycles, 5 degrees C to 55 degrees C). The microtensile bond strength test was performed in a universal testing machine (crosshead speed: 1 mm/min). The mean bond strengths of the specimens of each block were statistically analyzed using two-way ANOVA (alpha = 0.05). RESULTS: Both surface conditioning (p = 0.0001) and storage conditions (p = 0.0001) had a significant effect on the results. After 24 h water storage, silica coating and silanization (method 2) showed significantly higher bond strength results (46.4 +/- 13.8 MPa) than that of hydrofluoric acid etching and silanization (method 1) (35.8 +/- 9.7 MPa) (p < 0.001). After thermocycling, no significant difference was found between the mean bond strengths obtained with method 1 (34.1 +/- 8.9 MPa) and method 2 (31.9 +/- 7.9 MPa) (p > 0.05). CONCLUSION: Although after 24 h of testing, silica coating and silanization performed significantly better in resin-resin repair bond strength, both HF acid gel and silica coating followed by silanization revealed comparable bond strength results after thermocycling for 6000 times.


Assuntos
Resinas Compostas , Colagem Dentária , Corrosão Dentária/métodos , Reparação em Prótese Dentária , Análise de Variância , Análise do Estresse Dentário , Armazenamento de Medicamentos , Ácido Fluorídrico , Distribuição Aleatória , Silanos , Dióxido de Silício , Propriedades de Superfície , Resistência à Tração
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA