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1.
J Adhes Dent ; 23(3): 187-200, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34060299

RESUMO

PURPOSE: A systematic review and meta-analysis was conducted to compare the retention rates of 3-step etch-and-rinse (3ER) adhesives with 1-step self-etch (1SE) adhesives in noncarious cervical lesions (NCCLs). The secondary outcomes were marginal integrity and marginal discoloration. MATERIALS AND METHODS: Only randomized clinical trials (RCTs) that compared 1SE with 3ER in NCCLs were included. Controlled vocabulary and keywords were combined in the search strategy for PubMed/Medline, LILACS, BBO, Web of Science, Cochrane Library, grey literature, and IADR abstracts (1990-2018). The Cochrane Risk of Bias tool (RoB) was applied to eligible studies. Meta-analyses were conducted for retention rate and secondary outcomes at different follow-up times, using the random effects model. Heterogeneity was assessed with the Cochran Q test and I2 statistics. The GRADE approach was used to assess the quality of the evidence. RESULTS: After the removal of duplicates, title and abstract screening, 18 studies remained. Of these, 15 studies were used for meta-analysis. Fourteen out of these 15 were judged at "unclear" risk and 1 at "low" risk of bias. No significant differences between groups were observed in the different follow-up periods for retention rates 12 to 24 months (p = 0.66), 24 to 36 months (p = 0.21) and 60 months (p = 0.96). A significant difference in marginal integrity was found at 12 to 24 months (p = 0.04) and in marginal discoloration at 12 to 24 months (p = 0.003). CONCLUSION: There is no evidence that 3-step ER adhesives have better retention rates than 1-step SE adhesives in NCCLs.


Assuntos
Cimentos Dentários , Adesivos Dentinários
2.
Dent Mater ; 36(9): 1201-1213, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32576408

RESUMO

OBJECTIVE: To evaluate the influence of light emitted from two Polywave®, LED light-curing units (LCU) on in vivo pulp temperature (PT) rise and signs of acute inflammatory response in pulps of human premolar having deep Class V preparations. METHODS: Sixty intact, first premolars from 15 volunteers requiring extraction received infiltrative anesthesia. A sterile thermocouple probe was inserted within the pulp tissue through a minute occlusal pulp exposure in only 45 teeth (n = 9) to continuously monitor PT (°C). A deep buccal Class V preparation was created, and the surface was exposed to light from a commercial Polywave LCU (Bluephase 20i (20i), Ivoclar Vivadent) or from an experimental LCU (Exp) using the exposure modes (EM): 1s/Exp and 2s/Exp, 10s/20i, 20s/20i, and 60s/20i. Peak PT and PT rise values above baseline (ΔT) data were evaluated using a one-way ANOVA followed by Tukey's post-hoc test (α = 5%). Teeth used for histological and immunohistochemical analyses (n = 3) were extracted approximately 2 h after exposure to the LCU. RESULTS: No significant difference in peak PT and ΔT values was noted between 2s/Exp and 20s/20i groups, which both exhibited higher values than 1s/Exp and 10s/20i groups (p < 0.001). Dilated and congested blood vessels were seen after exposure to 1s/Exp, 2s/Exp, or 60s/20i EMs. The expression of IL-1ß and TNF-α tended to be more intense when higher irradiance was delivered. SIGNIFICANCE: Although higher irradiance delivered over a short exposure caused lower PT rise than 5.5 °C, such EMs should be used with caution, as they have more potential to harm the pulp tissue.


Assuntos
Luzes de Cura Dentária , Cura Luminosa de Adesivos Dentários , Dente Pré-Molar , Resinas Compostas , Polpa Dentária , Humanos , Temperatura
3.
Dent Mater ; 34(6): 901-909, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29606368

RESUMO

OBJECTIVE: This in vivo study evaluated pulp temperature (PT) rise in human premolars having deep Class V preparations during exposure to a light curing unit (LCU) using selected exposure modes (EMs). METHODS: After local Ethics Committee approval, intact first premolars (n=8) requiring extraction for orthodontic reasons, from 8 volunteers, received infiltrative and intraligamental anesthesia and were isolated using rubber dam. A minute pulp exposure was attained and sterile probe from a wireless, NIST-traceable, temperature acquisition system was inserted into the coronal pulp chamber to continuously monitor PT (°C). A deep buccal Class V preparation was prepared using a high speed diamond bur under air-water spray cooling. The surface was exposed to a Polywave® LED LCU (Bluephase 20i, Ivoclar Vivadent) using selected EMs, allowing 7-min span between each exposure: 10-s in low (10-s/L), 10-s (10-s/H), 30-s (30-s/H), or 60-s (60-s/H) in high mode; and 5-s-Turbo (5-s/T). Peak PT values and PT increases over physiologic baseline levels (ΔT) were subjected to 1-way, repeated measures ANOVAs, and Bonferroni's post-hoc tests (α=0.05). Linear regression analysis was performed to establish the relationship between applied radiant exposure and ΔT. RESULTS: All EMs produced higher peak PT than the baseline temperature (p<0.001). Only 60-s/H mode generated an average ΔT of 5.5°C (p<0.001). A significant, positive relationship was noted between applied radiant exposure and ΔT (r2=0.8962; p<0.001). SIGNIFICANCE: In vivo exposure of deep Class V preparation to Polywave® LED LCU increases PT to values considered safe for the pulp, for most EMs. Only the longest evaluated EM caused higher PT increase than the critical ΔT, thought to be associated with pulpal necrosis.


Assuntos
Luzes de Cura Dentária , Preparo da Cavidade Dentária/métodos , Polpa Dentária/efeitos da radiação , Dente Pré-Molar , Temperatura Alta , Humanos , Extração Dentária
4.
Dent Mater ; 33(11): 1266-1273, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28826611

RESUMO

OBJECTIVE: This study evaluated the temperature increase in swine gingival temperature after exposure to light emitted by a Polywave® LED light curing unit (LCU, Bluephase 20i, Ivoclar Vivadent). METHODS: After local Ethics Committee approval (protocol 711/2015), 40 pigs were subjected to general anesthesia and the LCU tip was placed 5mm from the buccal gingival tissue (GT) close to lower lateral incisors. A thermocouple probe (Thermes WFI, Physitemp) was inserted into the gingival sulcus before and immediately after exposure to light. Real-time temperature (°C) was measured after the following exposure modes were applied: High Power (20s-H, 40s-H, and 60s-H) or Turbo mode (5s-T), either with or without the presence of rubber dam (RD) interposed between the LCU tip and GT (n=10). The presence of gingival lesions after the exposures was also evaluated. Peak temperature (°C) and the temperature increase during exposure over that of the pre-exposure baseline value (ΔT) data were analyzed using 2-way ANOVA followed by Bonferroni's post-hoc test (α=5%). A binary logistic regression analysis determined the risk of gingival lesion development. RESULTS: Without RD, no significant difference in ΔT was observed among 20s-H, 40s-H, and 60s-H groups, which showed the highest temperature values, while the 5s-T exposure showed the lowest ΔT, regardless of RD. RD reduced ΔT only for the 20s-H group (p=0.004). Gingival lesions were predominantly observed using 40s-H, with RD, and 60s-H, with and without RD. SIGNIFICANCE: Exposure to a LCU light might be harmful to swine gingiva only when high radiant exposure values are delivered, regardless of the use of RD.


Assuntos
Luzes de Cura Dentária , Gengiva/efeitos da radiação , Temperatura , Animais , Lesões por Radiação/prevenção & controle , Suínos
5.
J Appl Oral Sci ; 25(2): 140-146, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28403354

RESUMO

Objective: Using Fourier transform infrared analysis (FTIR) in vitro, the effects of varying radiant exposure (RE) values generated by second and third generation LED LCUs on the degree of conversion (DC) and maximum rate of polymerization (Rpmax) of an experimental Lucirin TPO-based RC were evaluated. Material and Methods: 1 mm or 2 mm thick silicon molds were positioned on a horizontal attenuated total reflectance (ATR) unit attached to an infrared spectroscope. The RC was inserted into the molds and exposed to varying REs (18, 36 and 56 J/cm2) using second (Radii Plus, SDI) and third generation LED LCUs (Bluephase G2/Ivoclar Vivadent) or a quartz tungsten based LCU (Optilux 501/SDS Kerr). FTIR spectra (n=7) were recorded for 10 min (1 spectrum/s, 16 scans/spectrum, resolution 4 cm-1) immediately after their application to the ATR. The DC was calculated using standard techniques for observing changes in aliphatic to aromatic peak ratios both prior to, and 10 min after curing, as well as during each 1 second interval. DC and Rpmax data were analyzed using 3-way ANOVA and Tukey's post-hoc test (p=0.05). Results: No significant difference in DC or Rpmax was observed between the 1 mm or 2 mm thick specimens when RE values were delivered by Optilux 501 or when the 1 mm thick composites were exposed to light emitted by Bluephase G2, which in turn promoted a lower DC when 18 J/cm2 (13 s) were delivered to the 2 mm thick specimens. Radii Plus promoted DC and Rpmax values close to zero under most conditions, while the delivery of 56 J/cm2 (40 s) resulted in low DC values. Conclusions: The third generation LCU provided an optimal polymerization of Lucirin TPO-based RC under most tested conditions, whereas the second generation LED-curing unit was useless regardless of the RE.


Assuntos
Resinas Compostas/efeitos da radiação , Luzes de Cura Dentária , Cura Luminosa de Adesivos Dentários/métodos , Fosfinas/efeitos da radiação , Análise de Variância , Teste de Materiais , Transição de Fase , Fotoiniciadores Dentários/química , Polimerização/efeitos da radiação , Doses de Radiação , Valores de Referência , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo
6.
J. appl. oral sci ; 25(2): 140-146, Mar.-Apr. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-841182

RESUMO

Abstract Alternative photoinitiators with different absorption wavelengths have been used in resin composites (RCs), so it is crucial to evaluate the effectiveness of light-curing units (LCUs) on these products. Objective Using Fourier transform infrared analysis (FTIR) in vitro, the effects of varying radiant exposure (RE) values generated by second and third generation LED LCUs on the degree of conversion (DC) and maximum rate of polymerization (Rpmax) of an experimental Lucirin TPO-based RC were evaluated. Material and Methods 1 mm or 2 mm thick silicon molds were positioned on a horizontal attenuated total reflectance (ATR) unit attached to an infrared spectroscope. The RC was inserted into the molds and exposed to varying REs (18, 36 and 56 J/cm2) using second (Radii Plus, SDI) and third generation LED LCUs (Bluephase G2/Ivoclar Vivadent) or a quartz tungsten based LCU (Optilux 501/SDS Kerr). FTIR spectra (n=7) were recorded for 10 min (1 spectrum/s, 16 scans/spectrum, resolution 4 cm-1) immediately after their application to the ATR. The DC was calculated using standard techniques for observing changes in aliphatic to aromatic peak ratios both prior to, and 10 min after curing, as well as during each 1 second interval. DC and Rpmax data were analyzed using 3-way ANOVA and Tukey’s post-hoc test (p=0.05). Results No significant difference in DC or Rpmax was observed between the 1 mm or 2 mm thick specimens when RE values were delivered by Optilux 501 or when the 1 mm thick composites were exposed to light emitted by Bluephase G2, which in turn promoted a lower DC when 18 J/cm2 (13 s) were delivered to the 2 mm thick specimens. Radii Plus promoted DC and Rpmax values close to zero under most conditions, while the delivery of 56 J/cm2 (40 s) resulted in low DC values. Conclusions The third generation LCU provided an optimal polymerization of Lucirin TPO-based RC under most tested conditions, whereas the second generation LED-curing unit was useless regardless of the RE.


Assuntos
Fosfinas/efeitos da radiação , Resinas Compostas/efeitos da radiação , Cura Luminosa de Adesivos Dentários/métodos , Luzes de Cura Dentária , Doses de Radiação , Valores de Referência , Fatores de Tempo , Teste de Materiais , Reprodutibilidade dos Testes , Análise de Variância , Espectroscopia de Infravermelho com Transformada de Fourier , Transição de Fase , Fotoiniciadores Dentários/química , Polimerização/efeitos da radiação
7.
J Adhes Dent ; 18(6): 493-499, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27834412

RESUMO

PURPOSE: This study evaluated the push-out bond strength (BS) of fiber posts in root canals and the nanoleakage (NL) pattern at the bonding interface when universal adhesives were applied in etch-and-rinse mode to root dentin using an oscillating sonic device. MATERIALS AND METHODS: Fifty-four roots of human premolars were endodontically prepared and divided into 6 experimental groups according to the main factors: adhesive system/resin cement (Ambar Universal/AllCem, Scotchbond Universal/RelyX ARC, Prime&Bond Elect/Enforce) and application mode (vigorous manual or sonic). Fiber posts were cemented and roots were transversally sectioned into six 1-mm-thick serial slices, which were subjected to BS testing (n = 7 per group) at a crosshead speed of 0.5 mm/min, and the rest (n = 2 per group) were subjected to NL analysis using scanning electron microscopy after slice immersion in silver nitrate. Data were analyzed using two-way ANOVA and Bonferroni's post-hoc test (α = 5%). RESULTS: Sonic application significantly increased BS only on the coronal third when Ambar Universal was used. When Scotchbond Universal was used, higher BS was observed when the adhesive was manually applied than when the sonic device was used. For Prime&Bond Elect, no significant difference in BS was noted when the application methods were compared. Manual application also produced lower NL values than did sonic application when Ambar Universal was used, while no significant difference in NL was noted using the other adhesive systems. CONCLUSION: Sonic application did not improve the bond strength of posts in root canals in comparison to vigorous, manual application.


Assuntos
Bis-Fenol A-Glicidil Metacrilato , Cavidade Pulpar , Polietilenoglicóis , Ácidos Polimetacrílicos , Cimentos de Resina , Humanos , Teste de Materiais , Som
8.
Rev. ABENO ; 9(1): 34-38, 2009. ilus, tab
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-875011

RESUMO

O avanço científico que vem ocorrendo no Brasil elevou a necessitada de discussão sobre ética em pesquisa envolvendo seres humanos dentro das instituições de ensino superior. Para isso, a associação entre a arte persuasiva do cinema e a ética em pesquisa tem sido uma metodologia eficaz no que diz respeito ao processo de ensino-aprendizagem de alunos de graduação e pós-graduação. Assim, o objetivo deste projeto de extensão foi promover a discussão e o conhecimento sobre a ética em pesquisa envolvendo seres humanos com graduandos, pós-graduandos, professores e servidores públicos da Universidade Estadual de Ponta Grossa. Os resultados mostraram a efetividade do método, concluindo que os filmes contribuíram satisfatoriamente para o aprendizado e posicionamento ético de todos os participantes (AU).


The scientific advance that has occurred in Brazil increases the need to discuss ethics in human research within universities and research institutes. With this in mind, the association between the persuasive art of cinema and ethics research has been an effective methodology regarding the teaching and learning of undergraduate and graduate students. The aim of this extramural education project was to promote the discussion and understanding of ethics in human clinical research among undergraduate and graduate students, professors and public servants at Ponta Grossa State University. The results showed the effectiveness of this method. In conclusion, movies can contribute satisfactorily to the ethical learning and positioning of all participants (AU).


Assuntos
Humanos , Bioética/educação , Educação Superior , Ética em Pesquisa/educação , /estatística & dados numéricos , Brasil , Inquéritos e Questionários/estatística & dados numéricos
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