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1.
Int J Biol Macromol ; 271(Pt 1): 132577, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38795887

RESUMO

Staphylococcus aureus is a pathogen widely involved in wound infection due to its ability to release several virulence factors that impair the skin healing process, as well as its mechanism of drug resistance. Herein, sodium alginate and chitosan were combined to produce a hydrogel for topical delivery of neomycin to combat S. aureus associated with skin complications. The hydrogel was formulated by combining sodium alginate (50 mg/mL) and chitosan (50 mg/mL) solutions in a ratio of 9:1 (HBase). Neomycin was added to HBase to achieve a concentration of 0.4 mg/mL (HNeo). The incorporation of neomycin into the product was confirmed by scanning electron microscopy, FTIR and TGA analysis. The hydrogels produced are homogeneous, have a high swelling capacity, and show biocompatibility using erythrocytes and fibroblasts as models. The formulations showed physicochemical and pharmacological stability for 60 days at 4 ± 2 °C. HNeo totally inhibited the growth of S. aureus after 4 h. The antimicrobial effects were confirmed using ex vivo (porcine skin) and in vivo (murine) wound infection models. Furthermore, the HNeo-treated mice showed lower severity scores than those treated with HBase. Taken together, the obtained results present a new low-cost bioproduct with promising applications in treating infected wounds.


Assuntos
Alginatos , Antibacterianos , Quitosana , Hidrogéis , Neomicina , Staphylococcus aureus , Quitosana/química , Quitosana/farmacologia , Alginatos/química , Alginatos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Camundongos , Neomicina/farmacologia , Neomicina/química , Neomicina/administração & dosagem , Antibacterianos/farmacologia , Antibacterianos/química , Infecções Estafilocócicas/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/microbiologia , Infecções Cutâneas Estafilocócicas/patologia , Portadores de Fármacos/química , Pele/efeitos dos fármacos , Pele/microbiologia
2.
Dent Mater ; 39(11): 1051-1057, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37793951

RESUMO

OBJECTIVE: To evaluate the effect of dimethyl sulfoxide (DMSO) on the microtensile bond strength (µTBS) and nanoleakage (NL) of universal adhesives on eroded dentine, immediately and after four years of water storage. METHODS: Sixty-four sound human molars were distributed into 16 groups according to (1) Dentine surface (sound and eroded dentine); (2) dimethyl sulfoxide application (with or without); (3) Application mode (etch-and-rinse or self-etch) and (4) Storage time (immediate and four years). One mild universal adhesive was used (Scotchbond Universal). The restoration was then performed with a composite resin and the specimens were sectioned into resin-dentine bonded sticks. Resin-dentine bonded sticks were tested (immediately and after four years of water storage) for µTBS (0.5 mm/min) or used to assess NL. Data on µTBS and NL were analyzed using four-way ANOVA and Tukey's test (α = 0.05). RESULTS: Only the 3-way cross-product interaction 'substrate vs DMSO vs time' was statistically significant (p = 0.007). Eroded dentine showed a lower mean of µTBS and a higher mean of NL values than sound dentine. However, when DMSO was applied, no significant decrease of µTBS or NL values was observed after four years of water storage, regardless of adhesive strategies, or dentine evaluated, when compared to immediate results. SIGNIFICANCE: Water-based DMSO pre-treatments not only prevent degradation of MDP-containing simplified adhesives but also serve as a potential alternative to improve long-term bonding properties to eroded dentine. The versatility of using a single pre-treatment for both self-etch or etch-and-rinse bonding to eroded dentin may facilitate future clinical applications.


Assuntos
Colagem Dentária , Dimetil Sulfóxido , Humanos , Cimentos Dentários , Colagem Dentária/métodos , Adesivos Dentinários/química , Condicionamento Ácido do Dente/métodos , Cimentos de Resina/química , Dentina , Água/química , Resistência à Tração , Teste de Materiais
3.
J Dent ; 136: 104633, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37490967

RESUMO

OBJECTIVES: To evaluate the microtensile bond strength (µTBS) and nanoleakage (NL) of several universal adhesives to eroded dentine (ED) using etch-and-rinse (ER) and self-etch (SE) strategies, immediately and after 6 years of water storage. MATERIAL AND METHODS: Four hundred and eighty human molars were distributed into 60 groups according to dentine substrate (sound dentine [SD], eroded with soft drink, or eroded with citric acid), application method of the adhesive (SE or ER), and the adhesives used: 1. All-Bond Universal, 2. Ambar Universal, 3. Clearfil Universal, 4. Futurabond U, 5. One Coat 7 Universal, 6. Peak Universal Bond, 7. Prime&Bond Elect, 8. Scotchbond Universal, 9. Tetric n-bond Universal, and 10. Xeno Select. The restoration was then performed with a composite resin, and the specimens were sectioned into resin-dentine bonded sticks. The sticks were tested (immediately or after 6 years of storage) for µTBS (0.5 mm/min) or used to assess NL. The eroded dentine surfaces were also examined using FE-SEM to evaluate the NL. Data for µTBS were analyzed by four-way ANOVA and Tukey's post-hoc test (a = 0.05), and the NL was analyzed by Kruskal-Wallis and the Wilcoxon Signed Rank Sum test (a = 0.05). RESULTS: In ED, there was no difference in µTBS and NL between ER and SE strategies (p > 0.05). Most µTBS and NL values obtained for ED were lower and higher, respectively, than those for SD (p < 0.005). Additionally, the worst results (µTBS and NL) were observed for erosion with citric acid groups in comparison with erosion with soft-drink groups (p < 0.007). After 6y, µTBS was generally lower and NL higher for all substrates, adhesives, and strategies (p < 0.05), except for AMB, SBU, and TEU in dentine eroded with citric acid. The lowest µTBS and highest NL values were observed for ABU, FBU, OCU, PUB, PBE, and XEN in both types of eroded dentine and evaluation times (p < 0.002). CONCLUSION: The use of MDP-containing adhesives seems to be essential to maintain adhesion to eroded dentine. However, other factors such as acidity should be considered. CLINICAL SIGNIFICANCE: The bonding of eroded dentine is a challenge. However, the use of MDP-containing universal adhesives showed less degradation after long-term evaluation.


Assuntos
Colagem Dentária , Cimentos Dentários , Humanos , Adesivos Dentinários/química , Colagem Dentária/métodos , Cimentos de Resina/química , Água/química , Dentina , Resistência à Tração , Teste de Materiais , Adesivos
4.
Braz Oral Res ; 37: e033, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37132722

RESUMO

This study aimed to assess the potential association between perception malocclusion and school performance in children and adolescents. An electronic search was performed in ten databases. Based on the PECO acronym (Population, Exposition, Comparator, and Outcome), the eligibility criteria included observational studies that compared the school performance of children and adolescents with and without the perception of malocclusion. There were no restrictions on the language or year of publication. Two reviewers selected the studies, extracted the data, and assessed the risk of bias by using the Joanna Briggs Institute tool for cross-sectional studies. School performance was measured by analyzing student grades; levels of absenteeism; and child or adolescent self-perception and/or the perception of parents, guardians, close friends, and teachers regarding the impact of malocclusion on school performance. The data were described narratively/descriptively. The search resulted in 3,581 registers, of which eight were included in the qualitative synthesis. These studies were published between 2007 and 2021. Two studies concluded that there was no significant association between school performance and perception of malocclusion, five studies found that only some of the children with malocclusion had their school performance affected, and one study concluded that there was a significant association between perception of malocclusion and low school performance. Considering all variables and the very low certainty of evidence, the perception of malocclusion seems to negatively impact school performance when associated with external and subjective factors. Further studies using additional measurement standards are required.


Assuntos
Má Oclusão , Criança , Humanos , Adolescente , Estudos Transversais , Estudantes , Pais , Percepção
5.
Clin Oral Investig ; 27(1): 151-163, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36068369

RESUMO

OBJECTIVE: The aim of this double-blind, randomized clinical trial was to evaluate the 6- and 18-month clinical performances of a new universal adhesive applied in the "no-waiting" (NW) technique to non-carious cervical lesions (NCCLs) using two evaluation criteria. MATERIALS AND METHODS: One hundred and seventy-six restorations were assigned to four groups according to the adhesive system, adhesive strategy, and application mode: Prime&Bond Active (PB) applied using the etch-and-rinse (ER) and self-etch (SE) strategies with 20 s applications and Clearfil Universal Bond Quick (CQ) applied using the ER and SE strategies with the NW technique. The composite resin restorations were evaluated at baseline and after 6 and 18 months using the World Dental Federation (FDI) and US Public Health Service (USPHS) criteria. The Friedman repeated measures analysis of variance and Wilcoxon test were used for statistical analyses (α = 0.05). RESULTS: No significant differences were observed among any of the groups or criteria after 6 months (p > 0.05). After 18 months, 10 restorations were lost (p > 0.05) (2 with PB-ER [95.5%; 95%CI: 92-100%], 4 with PB-SE [90.9%; 95%CI: 82-98%], 0 with CQ-ER [100%; 95%CI: 92-100%], and 4 with CQ-SE [90.9%; 82-98%]). The restorations performed with the SE strategy showed more marginal discrepancies than those performed with the ER strategy, mainly when the FDI criteria were used (p < 0.05). Those that used the PB-SE showed fewer marginal discrepancies than those that used the CQ-SE (FDI; p < 0.05). A few restorations showed marginal discrepancies after the USPHS analysis (p > 0.05). CONCLUSIONS: The results when using the CQ-SE and -ER strategies with the NW technique were similar to those when using the PB-SE and -ER strategies in standard applications to non-carious cervical lesions after 6 and 18 months of clinical evaluation. CLINICAL RELEVANCE: After 6 and 18 months, the application of Clearfil Universal Bond Quick with the "no-waiting" technique showed similar clinical performance compared to the standard application of Prime & Bond Active applied using the standard application time (20 s). TRIAL REGISTRATION: ClinicalTrials.gov identifier RBR-5f9gps.


Assuntos
Cimentos Dentários , Adesivos Dentinários , Humanos , Adesivos Dentinários/química , Cimentos de Resina/química , Restauração Dentária Permanente/métodos , Método Duplo-Cego , Falha de Restauração Dentária , Resinas Compostas/uso terapêutico , Resinas Compostas/química , Adaptação Marginal Dentária
6.
Braz. oral res. (Online) ; 37: e033, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, BBO - Odontologia | ID: biblio-1430044

RESUMO

Abstract This study aimed to assess the potential association between perception malocclusion and school performance in children and adolescents. An electronic search was performed in ten databases. Based on the PECO acronym (Population, Exposition, Comparator, and Outcome), the eligibility criteria included observational studies that compared the school performance of children and adolescents with and without the perception of malocclusion. There were no restrictions on the language or year of publication. Two reviewers selected the studies, extracted the data, and assessed the risk of bias by using the Joanna Briggs Institute tool for cross-sectional studies. School performance was measured by analyzing student grades; levels of absenteeism; and child or adolescent self-perception and/or the perception of parents, guardians, close friends, and teachers regarding the impact of malocclusion on school performance. The data were described narratively/descriptively. The search resulted in 3,581 registers, of which eight were included in the qualitative synthesis. These studies were published between 2007 and 2021. Two studies concluded that there was no significant association between school performance and perception of malocclusion, five studies found that only some of the children with malocclusion had their school performance affected, and one study concluded that there was a significant association between perception of malocclusion and low school performance. Considering all variables and the very low certainty of evidence, the perception of malocclusion seems to negatively impact school performance when associated with external and subjective factors. Further studies using additional measurement standards are required.

7.
Materials (Basel) ; 15(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36079385

RESUMO

This in vitro study aimed to evaluate the effect of different bonding strategies on the micro-shear bond strength (µSBS) of luting agents to CAD−CAM composites. Surface scanning electron microscopy (SEM) and spectroscopy by energy-dispersive X-ray spectroscopy (EDS) were performed to analyze the surfaces of the composite before and after bonding treatment. Three CAD−CAM composites were evaluated: Lava Ultimate restorative (LU), Brava Blocks (BR), and Vita Enamic (VE). The LU and BR surfaces were sandblasted using aluminum oxide, while the VE surfaces were etched using a 5% hydrofluoric acid gel according to the manufacturers' recommendations. All surfaces were subjected to the following bonding strategies (n = 15): adhesive with silane and MDP (ScotchBond Universal, 3M Oral Care, St Paul, MI, USA); adhesive with MDP (Ambar Universal, FGM, Joinville, Brazil); adhesive without silane or MDP (Prime&Bond Elect, Dentsply Sirona, Charlotte, NC, USA), pure silane without MDP (Angelus, Londrina, Brazil), and pure silane with MDP (Monobond N, Ivoclar Vivadent, Schaan, Liechtenstei). Afterwards, tygons were filled with RelyX Ultimate (3M Oral Care), AllCem (FGM), or Enforce (Dentsply Sirona), which were light-cured and subjected to the µSBS test. Data were analyzed using two-way ANOVA and Bonferroni's post hoc test (α = 0.05). Additional blocks (n = 15) were subjected to scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) before and after the surface treatment. The µSBS values on VE surfaces were higher than those observed on LU and BR surfaces (p < 0.001). Silane without MDP (Allcem) promoted the highest µSBS values, while silane with MDP (RelyX Ultimate) provided the highest values among all bonding strategies (p < 0.001). Enforce promoted no significant difference in µSBS values. SEM and EDS analyses detected noticeable changes to the surface morphology and composition after the surface treatment. The effectiveness of the bonding strategy may vary according not only to the CAD−CAM composite but also to resin cement/bonding agent/silane used.

8.
J Funct Biomater ; 13(3)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36135584

RESUMO

Dental caries is a multifactorial, biofilm-dependent infectious disease that develops when detrimental changes occur in the oral cavity microenvironment. The antimicrobial and antivirulence properties of the essential oil obtained from the leaves of Eugenia brejoensis Mazine (EBEO) have been reported against Gram-positive and Gram-negative bacteria. Herein, the antimicrobial action of EBEO towards Streptococcus mutans is reported, along with the development and characterization of dental adhesives doped with. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of EBEO were determined against S. mutans, while its toxicity was analyze using Tenebrio molitor larvae. EBEO (MIC and 10×MIC) was incorporated into the Ambar Advanced Polymerization System® (Ambar APS), a two-step total-etch adhesive system (FGM Dental Group), and the antibiofilm action was evaluated. The reflective strength, modulus of elasticity, degree of conversion, and maximum rate of polymerization of each adhesive were also determined. The MIC and MBC values of EBEO against S. mutans were 62.5 µg/mL. The tested concentrations of EBEO were non-toxic to T. molitor larvae. The formation of S. mutans biofilms was significantly inhibited by EBEO and EBEO-coated resin discs (p < 0.05). Importantly, EBEO incorporation did not affect the mechanical and physicochemical properties in relation to oil-free adhesive version. EBEO showed strong antibacterial and antibiofilm activity against S. mutans, no toxicity effect against T. molitor larvae, and did not jeopardize the physical-chemical properties tested.

9.
Polymers (Basel) ; 14(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35808746

RESUMO

This paper evaluates the effect of an additional hydrophobic resin coat (extra HL) associated with universal adhesives on sound and eroded dentin and evaluated immediately or after 2 years of water storage to improve the microtensile bond strength (µTBS) and nanoleakage (NL) when compared to the use of universal adhesives only. Sixty-four molars were assigned to eight groups using the following combinations: 1. dentin substrate, including sound and eroded dentin; 2. treatment, including the control and extra HL and storage time (immediately and after two-years of storage). Two universal adhesives (Prime & Bond Active or Scotchbond Universal) were evaluated. Before restoration, half of the teeth were subjected to soft-drink erosion. Composite buildups were bonded; specimens were stored (37 °C/24 h), sectioned into resin−dentin bonded sticks and tested for microtensile bond strength and nanoleakage using SEM (immediately and after two-years of storage). Three-way ANOVA and Tukey's test (α = 0.05%) were used. In the immediate testing, the application of extra HL did not increase microtensile bond strength values compared with the control group in either substrate (p > 0.05). However, extra HL significantly decreased nanoleakage values when applied to eroded and sound dentin (p = 0.0001). After two years, the application of extra HL produced significantly higher microtensile bond strength and lower nanoleakage values than the control group for both adhesives (p = 0.0001). In all cases, sound dentin showed higher microtensile bond strength and lower nanoleakage values than eroded dentin (p = 0.000001). An extra HL increased the bond strength and reduced nanoleakage in eroded dentin after two-years of storage.

10.
Braz. dent. j ; Braz. dent. j;32(6): 93-106, Nov.-Dec. 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, BBO - Odontologia | ID: biblio-1355839

RESUMO

Abstract To investigate the effect of the dimethyl sulfoxide combined with cross-linking agents on microtensile bond strength, silver nitrate penetration and in situ degree of conversion analysis of adhesives to the erosive dentin treatment with Cola-based soft drink. One hundred and sixty-six molars were assigned to 20 groups: (1) Treatment: Sound dentin; Erosive dentin; Erosive dentin treated with primer of dimethyl sulfoxide; Erosive dentin treated with DMSO primer containing proanthocyanidin and rivoflavin; (2) Adhesive systems: iBond Universal and Scotchbond Universal; and (3) adhesive strategy: etch-and-rinse or self-etch strategy. After restoration, specimens were sectioned into sticks to be tested. The data from microtensile bond strength (MPa), silver nitrate penetration (%) and in situ degree of conversion (%) were analyzed by (three- and two-factor ANOVA; Tukey's test α=5%). The application of dimethyl sulfoxide combined of not with cross-linkers improved all properties evaluated when compared to only erosive dentin treatment with Cola-based soft drink. However, only when dimethyl sulfoxide was combined to cross-linkers, the values of the microtensile bond strength, silver nitrate penetration and in situ degree of conversion in erosive dentin treatment with Cola-based soft drink was similar to sound dentin, for both adhesives and adhesive strategies. The application of dimethyl sulfoxide combined with the collagen cross-linking agent contributed to increasing the bond strength and degree of conversion in erosive lesion dentin, at the same time that significantly reduction of nanoleakage in this substrate.


Resumo Este estudo investigou o efeito do dimetil sulfóxido combinado a agentes de reticulação de colágeno na resistência de união à microtração, infiltração de nitrato de prata e análise do grau de conversão por Micro-Raman de sistemas adesivos universais para a dentina erosionada por refrigerante a base de Cola. Cento e sessenta molares foram divididos em 20 grupos: (1) Tratamento: Dentina sadia; Dentina erosionada; Dentina erosionada tratada com primer de dimetil sulfóxido; Dentina erosionada tratada com primer contendo 6,5% de proantocianidina e; Dentina erosionada tratada com primer contendo 0,1% de rivoflavina; (2) Sistemas adesivos: iBond Universal e Scotchbond Universal; e (3) estratégia adesiva: estratégia condicionamento e lavagem ou autocondicionate. Após a restauração, os espécimes foram seccionados em palitos e testados. Os dados dos três testes foram analisados estatisticamente (ANOVA de 2 e 3 fatores e teste de Tukey; α = 5%). A aplicação de dimetil sulfóxido combinado ou não agentes de reticulação de colágeno melhorou todas as propriedades avaliadas quando comparado a dentina erosionada. Entretanto, apenas quando o dimetil sulfóxido foi combinado com agentes de reticulação de colágeno, os valores de adesão a dentina, infiltração de nitrato de prata e grau de conversão em dentina erosionada foi semelhante a dentina sadia, para os dois adesivos e estratégias adesivas. A aplicação de dimetil sulfóxido combinado com agentes de reticulação de colágeno contribuiu para aumentar a resistência de união e o grau de conversão dentro da camada híbrida na dentina erodida, ao mesmo tempo que reduziu significativamente a nanoinfiltração neste substrato.

11.
Braz Dent J ; 32(6): 93-106, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35019024

RESUMO

To investigate the effect of the dimethyl sulfoxide combined with cross-linking agents on microtensile bond strength, silver nitrate penetration and in situ degree of conversion analysis of adhesives to the erosive dentin treatment with Cola-based soft drink. One hundred and sixty-six molars were assigned to 20 groups: (1) Treatment: Sound dentin; Erosive dentin; Erosive dentin treated with primer of dimethyl sulfoxide; Erosive dentin treated with DMSO primer containing proanthocyanidin and rivoflavin; (2) Adhesive systems: iBond Universal and Scotchbond Universal; and (3) adhesive strategy: etch-and-rinse or self-etch strategy. After restoration, specimens were sectioned into sticks to be tested. The data from microtensile bond strength (MPa), silver nitrate penetration (%) and in situ degree of conversion (%) were analyzed by (three- and two-factor ANOVA; Tukey's test α=5%). The application of dimethyl sulfoxide combined of not with cross-linkers improved all properties evaluated when compared to only erosive dentin treatment with Cola-based soft drink. However, only when dimethyl sulfoxide was combined to cross-linkers, the values of the microtensile bond strength, silver nitrate penetration and in situ degree of conversion in erosive dentin treatment with Cola-based soft drink was similar to sound dentin, for both adhesives and adhesive strategies. The application of dimethyl sulfoxide combined with the collagen cross-linking agent contributed to increasing the bond strength and degree of conversion in erosive lesion dentin, at the same time that significantly reduction of nanoleakage in this substrate.


Assuntos
Colagem Dentária , Adesivos Dentinários , Colágeno , Cimentos Dentários , Dentina , Dimetil Sulfóxido , Teste de Materiais , Cimentos de Resina , Resistência à Tração
12.
Dental Press J Orthod ; 25(4): 59-67, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32965388

RESUMO

OBJECTIVE: To compare the effectiveness of the pretreatment with sandblasting and deproteinization with NaOCl on bond strength (SBS), in situ conversion degree (CD) of brackets in fluorotic enamel, and enamel etching pattern. METHODS: A total of 90 non-carious maxillary premolars were used. The teeth were then assigned to six experimental groups according to: enamel surface (sound and fluorotic enamel); surface treatment (Regular etch with 37% phosphoric acid [RE]; 5.2% sodium hypochlorite + phosphoric acid [NaOCl + RE]; sandblasting + phosphoric acid [sandblasting + RE]). After storage in distilled water (37°C/24h), the specimens were tested at 1 mm/min until failure (SBS). Enamel-resin cement interfaces were evaluated for CD using micro-Raman spectroscopy. The enamel-etching pattern was evaluated under a scanning electron microscope. Data from SBS and in situ CD values were analyzed using ANOVA two-away and Tukey test (α=0.05). The enamel etching pattern was evaluated only qualitatively. RESULTS: For sound enamel, RE showed the highest SBS values, when compared to NaOCl + RE and Sandblasting + RE groups (p< 0.01). Regarding CD, only NaOCl + RE significantly compromised the mean DC, in comparison with other groups (p= 0.002). For fluorotic enamel, the Sandblasting + RE group significantly increased the mean SBS values, in comparison with RE group (p= 0.01) and no significant change was observed for CD (p> 0.52). CONCLUSIONS: The application of NaOCl or sandblasting associated to phosphoric acid improved the SBS of the brackets in fluorotic enamel without compromising the CD of the resin cement, with improving of enamel interprismatic conditioning.


Assuntos
Colagem Dentária , Braquetes Ortodônticos , Condicionamento Ácido do Dente , Cimentos Dentários , Esmalte Dentário , Teste de Materiais , Ácidos Fosfóricos , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície
13.
Dental press j. orthod. (Impr.) ; 25(4): 59-67, July-Aug. 2020. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1133682

RESUMO

ABSTRACT Objective: To compare the effectiveness of the pretreatment with sandblasting and deproteinization with NaOCl on bond strength (SBS), in situ conversion degree (CD) of brackets in fluorotic enamel, and enamel etching pattern. Methods: A total of 90 non-carious maxillary premolars were used. The teeth were then assigned to six experimental groups according to: enamel surface (sound and fluorotic enamel); surface treatment (Regular etch with 37% phosphoric acid [RE]; 5.2% sodium hypochlorite + phosphoric acid [NaOCl + RE]; sandblasting + phosphoric acid [sandblasting + RE]). After storage in distilled water (37°C/24h), the specimens were tested at 1 mm/min until failure (SBS). Enamel-resin cement interfaces were evaluated for CD using micro-Raman spectroscopy. The enamel-etching pattern was evaluated under a scanning electron microscope. Data from SBS and in situ CD values were analyzed using ANOVA two-away and Tukey test (α=0.05). The enamel etching pattern was evaluated only qualitatively. Results: For sound enamel, RE showed the highest SBS values, when compared to NaOCl + RE and Sandblasting + RE groups (p< 0.01). Regarding CD, only NaOCl + RE significantly compromised the mean DC, in comparison with other groups (p= 0.002). For fluorotic enamel, the Sandblasting + RE group significantly increased the mean SBS values, in comparison with RE group (p= 0.01) and no significant change was observed for CD (p> 0.52). Conclusions: The application of NaOCl or sandblasting associated to phosphoric acid improved the SBS of the brackets in fluorotic enamel without compromising the CD of the resin cement, with improving of enamel interprismatic conditioning.


RESUMO Objetivo: Comparar a efetividade do pré-tratamento com jateamento e desproteinização com NaOCl na resistência de união (SBS), grau de conversão in situ (GC) dos braquetes metálicos ao esmalte fluorótico e o padrão de condicionamento do esmalte. Métodos: Foi utilizado um total de 90 pré-molares superiores livres de cárie. Os dentes foram divididos em seis grupos experimentais, de acordo com: superfície do esmalte (Esmalte Sadio e Fluorótico); tratamento de superfície (Condicionamento com ácido fosfórico a 37% [ER]; Hipoclorito de sódio a 5,2% + ácido fosfórico [NaOCl + ER]; e jateamento + ácido fosfórico [Jateamento + ER]). Após armazenamento em água destilada (37oC/24 h), os espécimes foram testados a 1 mm/min até a falha (SBS). As interfaces esmalte-cimento foram avaliadas para GC usando espectroscopia micro-Raman. O padrão do condicionamento do esmalte foi avaliado sob microscopia eletrônica de varredura. Os dados da SBS e GC foram analisados utilizando ANOVA dois fatores e teste de Tukey (α= 0,05). O padrão de condicionamento do esmalte foi avaliado apenas qualitativamente. Resultados: Para o esmalte sadio, o ER apresentou os maiores valores de SBS, quando comparado aos grupos NaOCl + ER e Jateamento + ER (p< 0,01). Em relação ao GC, apenas a média do grupo NaOCl + ER foi comprometida significativamente em comparação aos outros grupos (p= 0,002). Para o esmalte fluorótico, Jateamento + ER aumentou significativamente a média dos valores de SBS, em comparação com o grupo ER (p= 0,01) e nenhuma mudança significativa foi observada no GC (p> 0,52). Conclusões: A aplicação de NaOCl ou jateamento associado ao ácido fosfórico melhorou a SBS dos braquetes no esmalte fluorótico sem comprometer o GC do cimento resinoso, com a melhoria do condicionamento interprismático do esmalte.


Assuntos
Colagem Dentária , Braquetes Ortodônticos , Ácidos Fosfóricos , Propriedades de Superfície , Condicionamento Ácido do Dente , Teste de Materiais , Cimentos de Resina , Cimentos Dentários , Esmalte Dentário , Resistência ao Cisalhamento
14.
Clin Oral Investig ; 24(2): 809-822, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31190231

RESUMO

OBJECTIVES: The aim of this study was to investigate the effects of collagen cross-linking agents on nanomechanical and bonding properties of eroded dentin (ED), 24 h and 2 years after water storage. MATERIALS AND METHODS: Human molar dentin surfaces, eroded by soft drinks or citric acid, were acid-etched and treated with primers containing proanthocyanidin (PA) and riboflavin (RI) or were untreated (control) and tested after 24 h and 2 years. After acid etching and adhesive application (Prime&Bond Elect (PBE); Scotchbond Universal (SBU); Tetric n-bond Universal (TEU)), specimens were sectioned into beams and tested for microtensile bond strength (µTBS) and silver nitrate deposition (NL) after 24 h and 2 years. The beams were used to evaluate the 24-h in situ conversion of degree (DC). Nanohardness (NH) and Young's modulus (YM) were evaluated via resin-bonded dentin slices after 24 h and 2 years. A three-way ANOVA and Tukey's test were used for statistical analysis (5%). RESULTS: For both storage times, ED with citric acid resulted in lower µTBS, NH, and YM and higher NL for each adhesive system than soft drink ED (p < 0.05). After 2 years of water storage, cross-linking primers maintained the µTBS, NH, and YM (p < 0.05) when compared with the control group. Althougth, the NL values decreased for all groups after 2 years of water storage, PA and RI treatments showed NI values lower than control group (p < 0.001). No significant differences were observed between PA and RI treatments (p > 0.05). Cross-linking primers maintain or improve DC (p < 0.03). In general, TEU and SBU yielded higher µTBS, DC, NH, and YM and lower NL than PBE. CONCLUSION: Cross-linking agents improved the results and maintained the resin-ED interface bonding and nanomechanical properties, without jeopardizing adhesive polymerization. CLINICAL RELEVANCE: Cross-linking agents are a viable alternative for improving and maintaining resin-ED interface bonding and nanomechanical properties.


Assuntos
Colagem Dentária , Colágeno , Resinas Compostas , Dentina , Adesivos Dentinários , Humanos , Teste de Materiais , Cimentos de Resina , Resistência à Tração , Água
15.
Braz Oral Res ; 33: e120, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31778475

RESUMO

The objective of this study is to compare the resin-enamel bond strength (mµSBS), in-situ degree of conversion (DC), and the enamel-etching pattern (SEM/EDX) of universal adhesive systems when applied to sound and fluorotic enamel. Ninety-eight human molars were sectioned into 4 parts and divided into 24 groups according to 1) enamel surface (sound or fluorotic enamel), 2) adhesive system (Clearfil Universal Bond [CUB], Futurabond U [FBU], iBond Universal [IBU], and Scotchbond Universal [SBU]), and 3) application mode (etch-and-rinse [ER], active self-etch [Active-SE], and passive self-etch [Passive-SE]). Specimens were stored at 37 °C, for 24 hours and tested at 1.0 mm/min (µSBS). Enamel-resin interfaces were evaluated for in-situ DC. The enamel-etching pattern was evaluated under a SEM/EDX. Data from mµSBS and in-situ DC was analyzed using a three-way ANOVA and Tukey's test at 5 % level of significance. For all adhesives, the ER resulted in a statistically significant higher mean mµSBS than the passive-SE in both substrates (p < 0.001). For all adhesives, active-SE resulted in mean mµSBS (p > 0.31) and in-situ DC (p > 0.45) that were statistically similar to those obtained with the ERs in both substrates. A statistically significant, higher mean mµSBS and in-situ DC were obtained in sound enamel (p < 0.001) than in fluorotic enamel. In general, SBU showed higher mean values for mµSBS and in-situ DC compared to those of CUB and IBU (p < 0.001). ER and active-SE showed the deepest enamel-etching pattern in both substrates. A higher amount of fluor was observed in fluorotic enamel. The active application of universal adhesives in the SE-mode may be a viable alternative to increase the adhesive properties in sound and fluorotic enamel.


Assuntos
Colagem Dentária/métodos , Esmalte Dentário/química , Esmalte Dentário/efeitos dos fármacos , Fluorose Dentária , Cimentos de Resina/química , Análise de Variância , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Distribuição Aleatória , Valores de Referência , Reprodutibilidade dos Testes , Resistência ao Cisalhamento/efeitos dos fármacos , Espectrometria por Raios X , Análise Espectral Raman , Propriedades de Superfície/efeitos dos fármacos
16.
Clin Oral Investig ; 23(10): 3673-3689, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31468261

RESUMO

OBJECTIVES: A systematic review and meta-analysis were performed to answer this research question: "Does combined in-office (IO) and at-home (AH) bleaching produce improved color change and lower tooth sensitivity (TS) better than solely AH or IO bleaching in adults?" MATERIAL AND METHODS: Randomized controlled trials in adults that compared combined versus sole application bleaching were included. The risk of bias (RoB) was evaluated using the Cochrane Collaboration tool. Meta-analyses were conducted for color change in shade guide units (∆SGU) and with a spectrophotometer (∆E*), risk, and intensity of TS, using the random effects model. Heterogeneity was assessed with Cochran's Q test and I2 statistics. GRADE assessed the quality of the evidence. PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, SIGLE, IADR abstracts, unpublished, ongoing trial registries, dissertations, and theses were searched on August 28, 2017 (updated on January 29, 2019). RESULTS: Twelve studies remained. Two were considered to have low RoB. For combined vs. IO bleaching, no significant difference for ∆E*, ∆SGU, and risk of TS were observed; data were not available to analyze the intensity of TS. For combined vs. AH bleaching, no significant difference for ∆E*, ∆SGU, but lower TS to risk (RR 1.40, 95% 1.10 to 1.80) and intensity (MD 1.40, 95% CI 0.18 to 2.63) were detected for AH bleaching. Quality of evidence was graded as low or very low in all meta-analyses. CONCLUSION: Lower risk and intensity of TS was observed for the solely AH group without jeopardizing color change. However, more studies are still encouraged due to the low quality of evidence for most of the outcomes. CLINICAL RELEVANCE: If clinicians are to choose between combined or sole AH bleaching, the solely AH may be preferable; combined bleaching may potentiate the risk of TS without benefits in color change. For combined or sole IO bleaching, no important clinical difference in color change and risk of TS were detected; however, intensity of TS could not be compared due to lack of data. Further studies should be conducted due to the low/very low quality of the evidence.


Assuntos
Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Dente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
Braz Dent J ; 30(2): 171-178, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30970061

RESUMO

To evaluate the effect of combining 5% hydrofluoric acid (HF) and silane (SI) with the self-etching ceramic primer on the immediate and after 1-year of water storage on bonding efficacy, conditioning pattern (CP) and chemical interaction (CI) to the lithium disilicate. A total of 16 CAD/CAM blocks of lithium disilicate (LD) were cut into four square sections (n=64). For bonding efficacy evaluation, the LD specimens were divided into 4 groups (n=10): 1) HF+SI; 2) self-etching ceramic primer (MEP); 3) HF+MEP; 4) MEP+SI. After each treatment, an adhesive system was applied and Tygon matrices were filled with a dual-cured resin cement followed by light curing. Cylinder specimens (0.8 mmx0.5mm) were stored in water (37 °C for 24 h or 1-year) and submitted to the µSBS test (2-way ANOVA and Tukey's test; a=0.05). CP and CI were only evaluated qualitatively. No significant difference on the µSBS was observed between groups (p=0.73), but reduced µSBS was observed after 1-year of water storage (p>0.0001). After application of HF+SI and MEP, reduction in a number of siloxane bonds was observed, suggesting the coupling of SI on the LD surface. HF or HF+MEP produced a higher dissolution of the glassy matrix than the use of MEP alone. The MEP can be an alternative to traditional ceramic treatment once the chemical interaction and long-term bond strength were similar between both groups. The association of hydrofluoric acid or silane with a self-etching ceramic primer did not add any benefits in terms of chemical interaction and bonding stability.


Assuntos
Colagem Dentária , Ácido Fluorídrico , Cerâmica , Porcelana Dentária , Análise do Estresse Dentário , Teste de Materiais , Cimentos de Resina , Silanos , Propriedades de Superfície
18.
Braz. dent. j ; Braz. dent. j;30(2): 171-178, Mar.-Apr. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1001436

RESUMO

Abstract To evaluate the effect of combining 5% hydrofluoric acid (HF) and silane (SI) with the self-etching ceramic primer on the immediate and after 1-year of water storage on bonding efficacy, conditioning pattern (CP) and chemical interaction (CI) to the lithium disilicate. A total of 16 CAD/CAM blocks of lithium disilicate (LD) were cut into four square sections (n=64). For bonding efficacy evaluation, the LD specimens were divided into 4 groups (n=10): 1) HF+SI; 2) self-etching ceramic primer (MEP); 3) HF+MEP; 4) MEP+SI. After each treatment, an adhesive system was applied and Tygon matrices were filled with a dual-cured resin cement followed by light curing. Cylinder specimens (0.8 mmx0.5mm) were stored in water (37 °C for 24 h or 1-year) and submitted to the μSBS test (2-way ANOVA and Tukey's test; a=0.05). CP and CI were only evaluated qualitatively. No significant difference on the μSBS was observed between groups (p=0.73), but reduced μSBS was observed after 1-year of water storage (p>0.0001). After application of HF+SI and MEP, reduction in a number of siloxane bonds was observed, suggesting the coupling of SI on the LD surface. HF or HF+MEP produced a higher dissolution of the glassy matrix than the use of MEP alone. The MEP can be an alternative to traditional ceramic treatment once the chemical interaction and long-term bond strength were similar between both groups. The association of hydrofluoric acid or silane with a self-etching ceramic primer did not add any benefits in terms of chemical interaction and bonding stability.


Resumo Avaliar o efeito da combinação de ácido fluorídrico ou silano com o primer autocondicionante de cerâmicas sobre a eficácia da união imediata e após 1 ano de armazenamento em água, padrão de condicionamento e interação química desses tratamentos com o dissilicato de lítio. Um total de 16 blocos CAD/CAM de dissilicato de lítio (DL) foram cortados em quatro seções quadradas (n=64). Os espécimes de DL foram divididos em 4 grupos: 1) ácido fluorídrico a 5% + silano (HF + SI); 2) primer autocondicionante de cerâmica (MEP); 3) HF + MEP; 4) MPE + SI. Após cada tratamento, o sistema adesivo foi aplicado e as matrizes Tygon foram preenchidas com cimento resinoso dual (Variolink® II), seguido de fotopolimerização. Espécimes em forma de cilindro (0.8 mmÆ x 0.5 mm), foram armazenados em água (37 °C por 24h ou 1 ano) e submetidos ao teste μSBS (ANOVA dois fatores e teste de Tukey; a=0,05). Para avaliação das interações químicas por Espectroscopia Raman, os espécimes de DL foram divididos em 3 grupos (n=4): 1) sem tratamento (DL); 2) HF + SI; e 3) MEP. Para avaliação do padrão de condicionamento da superfície cerâmica após os tratamentos por MEV, os espécimes de DL foram divididos em 3 grupos (n=3): 1) DL; 2) HF; 3) MEP; e 4) HF + MEP. Ambos os métodos foram avaliados apenas qualitativamente. Não foi observada diferença significativa na μSBS imediata entre os grupos (p=0,73), mas após 1 ano de armazenamento das amostras em água, reduziu μSBS (p>0,0001). HF ou HF + MEP produziram uma maior dissolução da matriz vítrea do que o uso de MEP sozinho. Após a aplicação de SI e MEP, observou-se redução de ligações de siloxano, sugerindo o acoplamento da camada de silano na superfície do DL. O primer autocondicionante cerâmico pode ser uma alternativa ao tratamento cerâmico tradicional, uma vez que a interação química e a resistência de união a longo prazo, quando comparada ao tratamento tradicional foram estatisticamente semelhantes. A associação de ácido fluorídrico ou agente de acoplamento silano com um primer autocondicionante de cerâmicas não agregou nenhum benefício em termos de interação química e estabilidade.


Assuntos
Colagem Dentária , Ácido Fluorídrico , Silanos , Propriedades de Superfície , Teste de Materiais , Cerâmica , Cimentos de Resina , Porcelana Dentária , Análise do Estresse Dentário
19.
Odontol. clín.-cient ; 12(4): 281-285, Out.-Dez. 2013. graf, tab
Artigo em Português | LILACS | ID: lil-778264

RESUMO

Objetiva-se avaliar a eficiência de três métodos de fotoativação sobre quatro resinas compostas, através do ensaio de microdureza Knnop. Quatro resinas compostas foram selecionadas: R1-NaturalLook®- DFL, R2-Opallis®-FGM, R3-Ice®-SDI e R4-FiltekTMZ350XT 3M/ESPE. Um total de 120 amostras, divididas em 4 grupos experimentais (n=30), sendo 10 fotoativadas com luz halógena contínua (F1), 10 com o LED (F2) e 10 com luz halógena pulsátil (F3). A microdureza Knnop da superfície foi determinada em microdurômetro, sob uma carga de 50g por 15s, perfazendo um total de três indentações por amostra. Os dados obtidos foram analisados por ANOVA e teste de Tukey com 5% de significância. Para todos os materiais testados e métodos de fotoativação, a microdureza dos materiais R1 e R2 não foram influenciados pelos diferentes métodos (p>0,05), a microdureza do material R3 foi maior quando do uso da luz halógena contínua do que com luz halógena pulsátil (p<0,05) e a microdureza do material R4 quanto ao uso do LED foi inferior aos outros métodos. Das resinas microhíbridas a que apresentou microdureza superior foi a R3. A resina R4 obteve a melhor microdureza no estudo independente do método de fotoativação. A luz halógena continua apresentou resultado superior ao sistema de LED.


Objective is to evaluate the efficiency of three activation methods on four composite resins by testing microhardness Knnop. Four composites were selected: R1-NaturalLook®-DFL, R2-Opallis®-FGM, R3-Ice®-SDI and R4-FiltekTMZ350XT 3M/ESPE. A total of 120 samples were divided into 4 groups (n = 30), 10 light-cured with halogen light continuous (F1), 10 with LED (F2) and 10 with halogen light pulsed (F3). Microhardness Knnop surface was determined by microhardness under a load of 50g for 15s, for a total of three indentations per sample. Data were analyzed by ANOVA and Tukey's test at 5% significance. For all tested materials and methods of curing, the hardness of materials R1 and R2 were not influenced by different methods (p> 0.05), the hardness of the material R3 was greater when using halogen continuous light than halogen light pulsatile (p <0.05) and R4 microhardness of the material as the use of LED was less than other methods. Microhybrid resins that showed higher hardness was R3. The resin R4 achieved best in independent study hardness of polymerization method. The halogen light continuous showed superior results to LED system.

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