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1.
Dent Mater ; 39(9): 820-830, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37481368

RESUMO

OBJECTIVES: This study aimed to evaluate the effect of copper nanoparticles (CuNp) on the clinical performance of a universal adhesive system used as an etch-and-rinse or self-etch strategy. METHODS: A total of 216 class V (non-carious lesions) restorations were randomly placed in 36 subjects according to the following groups: ERcu, adhesive in etch-and-rinse with 0.1% CuNp; ERct, adhesive in etch-and-rinse without CuNp; SEcu, adhesive in self-etch with 0.1% CuNp; and Sect, adhesive in self-etch without CuNp. Restorations were evaluated at baseline and at 6, 12, 18, 36, and 48 months, using the FDI and USPHS criteria. Appropriate statistical analyses were performed (α = 0.05). RESULTS: After 48 months, 14 restorations were lost (two for ERcu, five for SEcu, and seven for SEct) and the retention rates (95% confidence interval [CI]) were 74.1% for ERcu (95% CI 61.1-83.8); 81.5% for ERct (95% CI 69.2-89.6); 64.8% (95% CI 51.5-76.2) for SEcu; and 64.8% (95% CI 51.5-76.2) for SEct, with statistical differences between SEct vs. ERct and SEcu vs. ERct (p < 0.05). No significant differences between the groups were observed when the secondary parameters were evaluated (p > 0.05). Nineteen restorations (two for ERcu, two for ERct, six for SEcu, and nine for SEct) showed minor marginal staining, and 44 restorations (7 for ERcu, 8 for ERct, 14 for SEcu, and 15 for SEct) presented minimal marginal adaptation defects. SIGNIFICANCE: This is the first long-term clinical trial to show that the addition of CuNp to a universal adhesive system does not affect clinical performance.


Assuntos
Cárie Dentária , Nanopartículas , Estados Unidos , Humanos , Cobre , Projetos de Pesquisa , Coloração e Rotulagem
2.
J Appl Oral Sci ; 31: e20220151, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37255180

RESUMO

OBJECTIVE: Many genes and signaling molecules are involved in orthodontic tooth movement, with mechanically and hypoxically stabilized HIF-1α having been shown to play a decisive role in periodontal ligament signaling during orthodontic tooth movement. Thus, this in vitro study aimed to investigate if genetic polymorphisms in HIF1A (Hypoxia-inducible factor α-subunits) influence the expression pattern of HIF-1α protein during simulated orthodontic compressive pressure. METHODOLOGY: Samples from human periodontal ligament fibroblasts were used and their DNA was genotyped using real time Polymerase chain reaction for the genetic polymorphisms rs2301113 and rs2057482 in HIF1A . For cell culture and protein expression experiments, six human periodontal ligament fibroblast cell lines were selected based on the patients' genotype. To simulate orthodontic compressive pressure in fibroblasts, a 2 g/cm2 force was applied under cell culture conditions for 48 hours. Protein expression was evaluated by Western Blot. Paired t-tests were used to compare HIF-1α expression with and without compressive pressure application and unpaired t-tests were used to compare expression between the genotypes in rs2057482 and rs2301113 (p<0.05). RESULTS: The expression of HIF-1α protein was significantly enhanced by compressive pressure application regardless of the genotype (p<0.0001). The genotypes in the genetic polymorphisms rs2301113 and rs2057482 were not associated with HIF-1α protein expression (p>0.05). CONCLUSIONS: Our study confirms that compressive pressure application enhances HIF-1α protein expression. We could not prove that the genetic polymorphisms in HIF1A affect HIF-1α protein expression by periodontal ligament fibroblasts during simulated orthodontic compressive force.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Ligamento Periodontal , Polimorfismo Genético , Humanos , Western Blotting , Fibroblastos , Genótipo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética
3.
J. appl. oral sci ; 31: e20220151, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1440420

RESUMO

Abstract Objective Many genes and signaling molecules are involved in orthodontic tooth movement, with mechanically and hypoxically stabilized HIF-1α having been shown to play a decisive role in periodontal ligament signaling during orthodontic tooth movement. Thus, this in vitro study aimed to investigate if genetic polymorphisms in HIF1A (Hypoxia-inducible factor α-subunits) influence the expression pattern of HIF-1α protein during simulated orthodontic compressive pressure. Methodology Samples from human periodontal ligament fibroblasts were used and their DNA was genotyped using real time Polymerase chain reaction for the genetic polymorphisms rs2301113 and rs2057482 in HIF1A . For cell culture and protein expression experiments, six human periodontal ligament fibroblast cell lines were selected based on the patients' genotype. To simulate orthodontic compressive pressure in fibroblasts, a 2 g/cm2 force was applied under cell culture conditions for 48 hours. Protein expression was evaluated by Western Blot. Paired t-tests were used to compare HIF-1α expression with and without compressive pressure application and unpaired t-tests were used to compare expression between the genotypes in rs2057482 and rs2301113 (p<0.05). Results The expression of HIF-1α protein was significantly enhanced by compressive pressure application regardless of the genotype (p<0.0001). The genotypes in the genetic polymorphisms rs2301113 and rs2057482 were not associated with HIF-1α protein expression (p>0.05). Conclusions Our study confirms that compressive pressure application enhances HIF-1α protein expression. We could not prove that the genetic polymorphisms in HIF1A affect HIF-1α protein expression by periodontal ligament fibroblasts during simulated orthodontic compressive force.

4.
Restor Dent Endod ; 47(4): e45, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36518615

RESUMO

Objectives: This study evaluated the relationship between the battery charge level and irradiance of light-emitting diode (LED) light-curing units (LCUs) and how these variables influence the Vickers hardness number (VHN) of a bulk-fill resin. Materials and Methods: Four LCUs were evaluated: Radii Plus (SDI), Radii-cal (SDI), Elipar Deep Cure (Filtek Bulk Fill, 3M Oral Care), and Poly Wireless (Kavo Kerr). Irradiance was measured using a radiometer every ten 20-second activations until the battery was discharged. Disks (4 mm thick) of a bulk-fill resin (Filtek Bulk Fill, 3M Oral Care) were prepared, and the VHN was determined on the top and bottom surfaces when light-cured with the LCUs with battery levels at 100%, 50% and 10%. Data were analyzed by 2-way analysis of variance, the Tukey's test, and Pearson correlations (α = 5%). Results: Elipar Deep Cure and Poly Wireless showed significant differences between the irradiance when the battery was fully charged versus discharged (10% battery level). Significant differences in irradiance were detected among all LCUs, within each battery condition tested. Hardness ratios below 80% were obtained for Radii-cal (10% battery level) and for Poly Wireless (50% and 10% battery levels). The battery level showed moderate and strong, but non-significant, positive correlations with the VHN and irradiance. Conclusions: Although the irradiance was different among LCUs, it decreased in half of the devices along with a reduction in battery level. In addition, the composite resin effectiveness of curing, measured by the hardness ratio, was reduced when the LCUs' battery was discharged.

5.
Braz. j. oral sci ; 21: e225136, jan.-dez. 2022. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1354771

RESUMO

Aim: To evaluate the influence of cobalt-chromium (Co-Cr) coping fabrication methods and ceramic application on the marginal and internal fit of metal-ceramic crowns. Methods: Co-Cr copings for metal-ceramic crowns were prepared by lost wax casting or CAD-CAM machining of sintered blocks. The fit was analyzed using the silicone replica technique at four assessment points: marginal gap (MG), axial wall (AW), axio-occlusal (AO) angle, and central occlusal (CO) wall. After the initial analysis, the copings were ceramic-veneered with the layering technique, and the fit was again determined. Data were statistically analyzed by paired and unpaired Student's-t test (α=0.05). Results: Marginal and internal fit before ceramic application according to the coping manufacturing method showed significant differences only at CO (p < 0.001), with milled copings (137.98±16.71 µm) showing higher gap values than cast copings (112.86±8.57 µm). For cast copings, there were significant differences at MG (before 109.13±8.79 µm; after 102.78±7.18 µm) and CO (before 112.86±8.57 µm; after 104.07±10.63 µm) when comparing the fit before and after ceramic firing. For milled copings, there was significant difference only at AO (before 116.39±9.64 µm; after 108.54±9.26 µm). Conclusion: This study demonstrated that the coping fabrication method influenced the internal fit. Ceramic firing maintained or improved the fit of the metal-ceramic crowns. The marginal discrepancy of all restorations, before and after ceramic firing, can be considered clinically acceptable


Assuntos
Cerâmica , Ligas Metalo-Cerâmicas , Adaptação Marginal Dentária , Coroas
6.
Clin Oral Investig ; 26(3): 2281-2297, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35031879

RESUMO

OBJECTIVES: A systematic review was performed to analyze the clinical performance of class I and II restorations in posterior teeth placed with the incremental or the bulk-filling techniques. The primary outcome was retention/fracture rate, and the secondary outcomes evaluated were anatomical form, surface texture, color match, marginal adaption, marginal discoloration, caries, and postoperative sensitivity. METHODS: Electronic and manual searches were performed for randomized clinical trials comparing the clinical performance of composite resin restorations in posterior teeth placed with the incremental or the bulk-filling techniques. The Cochrane Collaboration risk of bias tool was used to assess the quality of the studies and the GRADE tool was used to access the quality of the evidence. RESULTS: Fourteen studies were included in this systematic review and most of them had unclear risk of bias. The risk difference (RD) for retention/fracture was 0.00 (95%CI = - 0.01, 0.01; p = 0.86) for 1-1.5 years of follow-up; 0.00 (95%CI = - 0.02, 0.02; p = 0.88) for 2-3 years of follow-up; 0.05 (95%CI = - 0.08, 0.18; p = 0.46) for 5 or more years of follow-up. The RD for postoperative sensitivity was 0.04 (95%CI = - 0.02, 0.10; p = 0.18) for up to 30 days; 0.00 (95%CI = - 0.01, 0.02; p = 0.63) for 1-1.5 years of follow-up; and 0.00 (95%CI = - 0.01, 0.02; p = 0.71) for 2-3 years of follow-up. For the other secondary outcomes, no significant differences were observed (p > 0.05) between the restorative techniques. The certainty of evidence was graded as moderate. CONCLUSIONS: The clinical performance of class I and II restorations in posterior teeth is similar when placed with the incremental and bulk-filling techniques. CLINICAL RELEVANCE: Based on the results of this study, posterior restorations placed with bulk-filling technique present satisfactory clinical performance, which is similar to direct restorations placed with the conventional incremental technique, considering various follow-up periods evaluated. TRIAL REGISTRATION:  CRD42018108450.


Assuntos
Resinas Compostas , Cárie Dentária , Resinas Compostas/uso terapêutico , Cárie Dentária/tratamento farmacológico , Adaptação Marginal Dentária , Restauração Dentária Permanente/métodos , Humanos
7.
Braz Dent J ; 30(3): 259-265, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31166388

RESUMO

The objective was to evaluate the color stability of thin ceramic veneers as a function of the curing mode (with and without pre-cure) of different adhesive systems applied to the internal surface of ceramics. Five adhesive systems (Scotchbond Multi-Purpose, Single Bond Universal, Gluma 2 Bond, Ambar, and Ambar APS) and photo-cured resin cement (Allcem Veneer) were used for cementing 0.6 mm-thick feldspathic veneers (Mark II) on composite resin substrates (Charisma Diamond). The groups, according to adhesive system, were divided into two subgroups (n=10): i) adhesive and resin cement were polymerized separately (pre-cure of the adhesive), ii) adhesive and resin cement were polymerized simultaneously. The CIELab color parameters were determined with a spectrophotometer at 24h (baseline), 7 days, 30 days and 12 months. Data were analyzed by two-way ANOVA and Tukey's test (α=0.05). The results indicated statistically significant differences for adhesive systems and time. The mode of curing of the adhesive system was not statistically significant: pre-cured adhesives (2.6±1.3) and not pre-cured adhesives (2.8±1.4). For the adhesives, ΔE values varied in the following order: Ambar-APS (1.6±0.5) < Scotchbond Multi-Purpose (2.6±1.2) = Gluma 2 Bond (2.7±1.2) = Ambar (2.9±1.2) < Single Bond Universal (3.5±1.5). For time, ΔE values were: 7 days (1.7±0.7), 30 days (3.5±1.2) and 12 months (2.9±1.3). It can be concluded that the different adhesive systems used for cementing thin ceramic veneers influenced the final color of the indirect restorations. The adhesives curing mode did not present a significant effect in the color stability of thin ceramic veneers.


Assuntos
Cimentos Dentários , Facetas Dentárias , Cerâmica , Cor , Cura Luminosa de Adesivos Dentários , Teste de Materiais , Cimentos de Resina
8.
Braz. dent. j ; 30(3): 259-265, May-June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1011543

RESUMO

Abstract The objective was to evaluate the color stability of thin ceramic veneers as a function of the curing mode (with and without pre-cure) of different adhesive systems applied to the internal surface of ceramics. Five adhesive systems (Scotchbond Multi-Purpose, Single Bond Universal, Gluma 2 Bond, Ambar, and Ambar APS) and photo-cured resin cement (Allcem Veneer) were used for cementing 0.6 mm-thick feldspathic veneers (Mark II) on composite resin substrates (Charisma Diamond). The groups, according to adhesive system, were divided into two subgroups (n=10): i) adhesive and resin cement were polymerized separately (pre-cure of the adhesive), ii) adhesive and resin cement were polymerized simultaneously. The CIELab color parameters were determined with a spectrophotometer at 24h (baseline), 7 days, 30 days and 12 months. Data were analyzed by two-way ANOVA and Tukey's test (α=0.05). The results indicated statistically significant differences for adhesive systems and time. The mode of curing of the adhesive system was not statistically significant: pre-cured adhesives (2.6±1.3) and not pre-cured adhesives (2.8±1.4). For the adhesives, ΔE values varied in the following order: Ambar-APS (1.6±0.5) < Scotchbond Multi-Purpose (2.6±1.2) = Gluma 2 Bond (2.7±1.2) = Ambar (2.9±1.2) < Single Bond Universal (3.5±1.5). For time, ΔE values were: 7 days (1.7±0.7), 30 days (3.5±1.2) and 12 months (2.9±1.3). It can be concluded that the different adhesive systems used for cementing thin ceramic veneers influenced the final color of the indirect restorations. The adhesives curing mode did not present a significant effect in the color stability of thin ceramic veneers.


Resumo O objetivo deste estudo foi avaliar a estabilidade de cor de laminados cerâmicos de espessura fina em função do momento de ativação de diferentes sistemas adesivos na superfície interna das cerâmicas. Foram utilizados 5 sistemas adesivos (Scotchbond Multiuso, Single Bond Universal, Gluma 2 Bond, Ambar and Ambar APS) e o cimento resinoso fotoativado (Allcem Veneer) para cimentação de lâminas de cerâmica feldspática (Mark II) com 0,6 mm de espessura, sobre substratos de resina composta (Charisma Diamond). Os grupos, de acordo com o sistema adesivo utilizado, foram divididos em dois subgrupos (n=10): i) adesivo e cimento resinoso foram polimerizados separadamente (polimerização isolada do adesivo), ii) adesivo e cimento resinoso foram polimerizados ao mesmo tempo (polimerização simultânea). Os parâmetros de cor do sistema CIELab foram determinados com um espectrofotômetro nos tempos de 24 h (baseline), 7 dias, 30 dias e 12 meses. Os dados foram analisados por ANOVA a dois fatores e teste de Tukey (α=0,05). Os resultados indicaram diferenças estatísticas significantes para os sistemas adesivos e tempo. O momento da fotoativação do sistema adesivo não foi estatisticamente significante: polimerização prévia (2,6±1,3) e polimerização simultânea (2,8±1,4). Para o sistema adesivo, os valores médios de ΔE variaram na seguinte ordem: Ambar APS (1,6±0,5)<Scotchbond Multi-Purpose (2,6±1,2)=Gluma 2 Bond (2,7±1,2)=Ambar (2,9±1,2)<Single Bond Universal (3,5±1,5). Para o fator tempo o ΔE foi: 7 dias (1,7±0,7), 30 dias (3,5±1,2) e 12 meses (2,9±1,3). Pode-se concluir que os diferentes sistemas adesivos utilizados na cimentação de laminados cerâmicos de espessura fina influenciaram na cor final das restaurações. O momento da fotoativação, isolada ou simultânea ao cimento resinoso, não apresentou efeito significativo na estabilidade de cor dos laminados cerâmicos de espessura fina.


Assuntos
Cimentos Dentários , Facetas Dentárias , Teste de Materiais , Cerâmica , Cor , Cimentos de Resina , Cura Luminosa de Adesivos Dentários
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