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1.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207218

RESUMO

Resin-based composite materials have been widely used in restorative dental materials due to their aesthetic, mechanical, and physical properties. However, they still encounter clinical shortcomings mainly due to recurrent decay that develops at the composite-tooth interface. The low-viscosity adhesive that bonds the composite to the tooth is intended to seal this interface, but the adhesive seal is inherently defective and readily damaged by acids, enzymes, and oral fluids. Bacteria infiltrate the resulting gaps at the composite-tooth interface and bacterial by-products demineralize the tooth and erode the adhesive. These activities lead to wider and deeper gaps that provide an ideal environment for bacteria to proliferate. This complex degradation process mediated by several biological and environmental factors damages the tooth, destroys the adhesive seal, and ultimately, leads to failure of the composite restoration. This paper describes a co-tethered dual peptide-polymer system to address composite-tooth interface vulnerability. The adhesive system incorporates an antimicrobial peptide to inhibit bacterial attack and a hydroxyapatite-binding peptide to promote remineralization of damaged tooth structure. A designer spacer sequence was incorporated into each peptide sequence to not only provide a conjugation site for methacrylate (MA) monomer but also to retain active peptide conformations and enhance the display of the peptides in the material. The resulting MA-antimicrobial peptides and MA-remineralization peptides were copolymerized into dental adhesives formulations. The results on the adhesive system composed of co-tethered peptides demonstrated both strong metabolic inhibition of S. mutans and localized calcium phosphate remineralization. Overall, the result offers a reconfigurable and tunable peptide-polymer hybrid system as next-generation adhesives to address composite-tooth interface vulnerability.


Assuntos
Antibacterianos/química , Cimentos Dentários/química , Proteínas Citotóxicas Formadoras de Poros/química , Antibacterianos/farmacologia , Resinas Compostas/química , Resinas Compostas/farmacologia , Cimentos Dentários/farmacologia , Metacrilatos/química , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Streptococcus mutans/efeitos dos fármacos , Remineralização Dentária/métodos
2.
Sci Rep ; 11(1): 11806, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34083707

RESUMO

The aim of this study was to investigate whether experimental and commercial dental restorative materials with functional fillers can exert a protective anti-demineralizing effect on enamel that is not immediately adjacent to the restoration. Four experimental resin composites with bioactive glass and three commercial restorative materials were investigated. Enamel blocks were incubated in a lactic acid solution (pH = 4.0) at a standardized distance (5 mm) from cured specimens of restorative materials. The lactic acid solution was replenished every 4 days up to a total of 32 days. Surfaces of enamel blocks were periodically evaluated by Knoop microhardness measurements and scanning electron microscopy. The protective effect of restorative materials against acid was identified as enamel microhardness remaining unchanged for a certain number of 4-day acid addition cycles. Additionally, the pH of the immersion medium was measured. While enamel microhardness in the control group was maintained for 1 acid addition cycle (4 days), restorative materials postponed enamel softening for 2-5 cycles (8-20 days). The materials capable of exerting a stronger alkalizing effect provided longer-lasting enamel protection. The protective and alkalizing effects of experimental composites improved with higher amounts of bioactive glass and were better for conventional bioactive glass 45S5 compared to a fluoride-containing bioactive glass. Scanning electron micrographs evidenced the protective effect of restorative materials by showing a delayed appearance of an etching pattern on the enamel surface. A remotely-acting anti-demineralizing protective effect on enamel was identified in experimental composites functionalized with two types of bioactive glass, as well as in three commercial ion-releasing restorative materials.


Assuntos
Cariostáticos/farmacologia , Resinas Compostas/farmacologia , Esmalte Dentário/efeitos dos fármacos , Desmineralização do Dente/prevenção & controle , Fenômenos Químicos , Esmalte Dentário/ultraestrutura , Humanos , Concentração de Íons de Hidrogênio , Teste de Materiais , Propriedades de Superfície
3.
PLoS One ; 16(4): e0249551, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33819292

RESUMO

Fabricating method may affect the surface properties and biological characteristics of provisional restorations. This study aimed to evaluate the surface roughness, plaque accumulation, and cytotoxicity of provisional restorative materials fabricated by the conventional, digital subtractive and additive methods. Sixty-six bar-shaped specimens (2×4×10 mm) were fabricated by using provisional restorative materials through the conventional, digital subtractive and additive methods (n = 22 per group). Ten specimens of each group were used for surface roughness and plaque accumulation tests, 10 specimens for cytotoxicity assay, and 2 specimens of each group were used for qualitative assessment by scanning electron microscopy. The Ra (roughness average) and Rz (roughness height) values (µm) were measured via profilometer, and visual inspection was performed through scanning electron microscopy. Plaque accumulation of Streptococcus mutans and cytotoxicity on human gingival fibroblast-like cells were evaluated. The data were analyzed with one-way ANOVA and Tukey's post hoc test (α = 0.05). Surface roughness, biofilm accumulation and cytotoxicity were significantly different among the groups (P<0.05). Surface roughness was significantly higher in the conventional group (P<0.05); however, the two other groups were not significantly different (P>0.05). Significantly higher bacterial attachment was observed in the additive group than the subtractive (P<0.001) and conventional group (P = 0.025); while, the conventional and subtractive groups were statistically similar (P = 0.111). Regarding the cytotoxicity, the additive group had significantly higher cell viability than the subtractive group (P = 0.006); yet, the conventional group was not significantly different from the additive (P = 0.354) and subtractive group (P = 0.101). Surface roughness was the highest in conventionally cured group; but, the additive group had the most plaque accumulation and lowest cytotoxicity.


Assuntos
Biofilmes/crescimento & desenvolvimento , Resinas Compostas/farmacologia , Materiais Dentários/farmacologia , Placa Dentária/prevenção & controle , Restauração Dentária Permanente/métodos , Gengiva/efeitos dos fármacos , Streptococcus mutans/fisiologia , Sobrevivência Celular , Gengiva/patologia , Humanos , Teste de Materiais , Propriedades de Superfície
4.
Lasers Med Sci ; 36(5): 1109-1116, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33392782

RESUMO

The aim of this study was to evaluate the effect of 940 nm laser diode on class II composite cavities prior to bonding and restoration process on the postoperative sensitivity (POS). Thirty patients with two bilateral premolars with mesio or disto-occlusal carious lesions were evaluated. In each patient, the teeth were randomly divided into the control and laser groups. After cavity preparation and isolation and before the bonding process, the laser group was subjected to 940 nm irradiation (Epic 10, Biolase, USA) by 400 µ tip continuously at 100 mW with 398 J/cm2 energy density of tip, which was applied for 5 s at a distance of 2 mm on the axial wall of the cavity. In the control group, irradiation was performed by using the aiming beam. Access cavity was then restored with a composite resin. Cold sensitivity was measured using a cold spray application on the middle third of teeth buccal surface at baseline (before the intervention), 1, 14, and 30 days after the restoration by visual analog scale (VAS) criteria. The mean Friedman and Wilcoxon signed-rank tests were used for data analysis. It was shown that in both laser and control groups, the VAS was significantly decreased at all times compared to the baseline (p ≤ 0.05). There was no statistically significant difference between the mean VAS of two groups at baseline and first day (p ≤ 0.05), but at 14 and 30 days after the intervention, it was significantly lower in the laser group (p ≤ 0.05). The results of this study demonstrated that the cavity pretreatment with laser diode (940 nm) effectively reduces the postoperative sensitivity in class II composite restorations.


Assuntos
Resinas Compostas/farmacologia , Restauração Dentária Permanente/efeitos adversos , Sensibilidade da Dentina/etiologia , Sensibilidade da Dentina/prevenção & controle , Lasers Semicondutores/uso terapêutico , Boca , Adulto , Humanos , Período Pós-Operatório , Adulto Jovem
5.
Comput Methods Biomech Biomed Engin ; 24(5): 485-495, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33090047

RESUMO

3D tooth models were virtually restored: flowable composite resin + bulk-fill composite (A), glass ionomer cement + bulk-fill composite (B) or adhesive + bulk-fill composite (C). Polymerization shrinkage and masticatory loads were simulated. All models exhibited the highest stress concentration at the enamel-restoration interfaces. A and C showed similar pattern with lower magnitude in A in comparison to C. B showed lower stress in dentine and C the highest cusps displacement. The use of glass ionomer cement or flowable composite resin in combination with a bulk-fill composite improved the biomechanical behavior of deep class II MO cavities.


Assuntos
Adesivos/farmacologia , Cavidade Pulpar/efeitos dos fármacos , Análise de Elementos Finitos , Materiais Restauradores do Canal Radicular/farmacologia , Resinas Compostas/farmacologia , Reparação de Restauração Dentária , Análise do Estresse Dentário , Módulo de Elasticidade/efeitos dos fármacos , Cimentos de Ionômeros de Vidro/farmacologia , Humanos , Teste de Materiais , Modelos Anatômicos , Polimerização , Suporte de Carga
6.
Eur Cell Mater ; 40: 259-275, 2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-33242338

RESUMO

Ideal restoration material for caries would allow attachment of gingival epithelia. The attachment of epithelial cells to specimens of the 4 most commercially used well- or partially-cured resin composites, with and without TEGDMA, was assessed. Effects of resin composite on the Ca9-22 gingival epithelial cell-line were assessed by measuring the cytotoxicity, viability and gene expression for attachment, apoptosis, ROS-production, pro-inflammatory cytokines, and matrix metalloproteinases. As controls, cells on tissue culture plastic or bovine tooth enamel specimens were used. Significantly less cell attachment was measured on freshly made resin-composite specimens. Concomitantly, significantly higher cytotoxicity was measured in the presence of freshly made resin-composite specimens. However, after 8 d of leakage, the cell attachment to and cytotoxicity of the resin composite was comparable to bovine tooth enamel. Significantly higher expressions of IL6, MMP2, BCL6 and ITGA4 were measured in cells attached to resin-composite surfaces than controls. There were no significant differences between the results using different conditions of resin composite, with or without TEGDMA and well or partially cured. Less cell attachment and presence of more inflammatory markers were observed on all freshly-made resin-composite surfaces. However, after a leakage period attachment of cells to the resin composite improved to the level of natural tooth materials such as enamel. This indicated that the negative effects of resin composites on epithelial cells might be transient.


Assuntos
Resinas Compostas/farmacologia , Epitélio/fisiologia , Gengiva/fisiologia , Animais , Bovinos , Adesão Celular/efeitos dos fármacos , Contagem de Células , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/ultraestrutura , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/ultraestrutura , Epitélio/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Humanos
7.
Int J Mol Sci ; 21(19)2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33023018

RESUMO

Dental pulp is exposed to resin monomers leaching from capping materials. Toxic doses of the monomer, triethyleneglycol dimethacrylate (TEGDMA), impact cell growth, enhance inflammatory and oxidative stress responses, and lead to tissue necrosis. A therapeutic agent is required to rescue growth-arrested tissues by continuing their development and modulating the exacerbated responses. The functionality of N-Acetyl Cysteine (NAC) as a treatment was assessed by employing a 3D dental pulp microtissue platform. Immortalized and primary microtissues developed and matured in the extracellular matrix (ECM). TEGDMA was introduced at various concentrations. NAC was administered simultaneously with TEGDMA, before or after monomer addition during the development and after the maturation stages of the microtissue. Spatial growth was validated by confocal microscopy and image processing. Levels of inflammatory (COX2, NLRP3, IL-8) and oxidative stress (GSH, Nrf2) markers were quantified by immunoassays. NAC treatments, in parallel with TEGDMA challenge or post-challenge, resumed the growth of the underdeveloped microtissues and protected mature microtissues from deterioration. Growth recovery correlated with the alleviation of both responses by decreasing significantly the intracellular and extracellular levels of the markers. Our 3D/ECM-based dental pulp platform is an efficient tool for drug rescue screening. NAC supports compromised microtissues development, and immunomodulates and maintains the oxidative balance.


Assuntos
Acetilcisteína/farmacologia , Polpa Dentária/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Inflamação/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Resinas Compostas/farmacologia , Polpa Dentária/crescimento & desenvolvimento , Polpa Dentária/metabolismo , Avaliação Pré-Clínica de Medicamentos , Matriz Extracelular/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/patologia , Interleucina-8/genética , Fator 2 Relacionado a NF-E2/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Estresse Oxidativo/efeitos dos fármacos , Polietilenoglicóis/farmacologia , Ácidos Polimetacrílicos/farmacologia
8.
Niger J Clin Pract ; 23(7): 957-964, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32620725

RESUMO

Aim: The aims of this study were to evaluate the surface morphology and surface roughness of restorative materials containing glass ionomer, analyze Streptococcus mutans biofilm formation on the surface of materials, and determine the correlation between surface roughness and biofilm. Materials and Methods: Four restorative materials: resin-modified glass ionomer; giomer; amalgomer; and glass carbomer were used and for each material, 6 mm in diameter and 2 mm in thickness disc-shaped specimens were prepared to evaluate the surface morphology (n = 3), surface roughness (n = 16), and biofilm (n = 20). Surface morphology was analyzed with a scanning electron microscope. Surface roughness was evaluated via an atomic force microscope. The biofilm was evaluated by counting the colony-forming units. Surface roughness measurements were evaluated using a one-way analysis of variance and Tukey HSD test. Biofilm parameters were analyzed using the Kruskal-Wallis H and Mann-Whitney U test. Pearson's correlation test was used to determine the correlation between surface roughness and biofilm. Results: While the highest roughness values were obtained for amalgomer and glass carbomer, the lowest roughness values belonged to giomer and resin-modified glass ionomer. Statistically significant differences in the number of adherent bacteria were observed between the materials only on day 1. No statistically significant correlation was determined between surface roughness and biofilm. Conclusions: The resin content and small filler particle size of material positively affect surface roughness. However, there is no direct relationship between surface roughness and biofilm.


Assuntos
Apatitas/química , Biofilmes/crescimento & desenvolvimento , Resinas Compostas/farmacologia , Placa Dentária/prevenção & controle , Cimentos de Ionômeros de Vidro/química , Streptococcus mutans/crescimento & desenvolvimento , Resinas Acrílicas , Resinas Compostas/química , Placa Dentária/microbiologia , Restauração Dentária Permanente , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Dióxido de Silício , Streptococcus mutans/efeitos dos fármacos , Propriedades de Superfície
9.
J Dent ; 99: 103406, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32526346

RESUMO

OBJECTIVES: Polymerization shrinkage stress may lead to marginal damage, microleakage and failure of composite restorations. The objectives of this study were to : (1) develop a novel nanocomposite with low-shrinkage-stress, antibacterial and remineralization properties to reduce marginal enamel demineralization under biofilms; (2) evaluate the mechanical properties of the composite and calcium (Ca) and phosphate (P) ion release; and (3) investigate the cytotoxicity of the new low-shrinkage-stress monomer in vitro. METHODS: The low-shrinkage-stress resin consisted of urethane dimethacrylate (UDMA) and triethylene glycol divinylbenzyl ether (TEG-DVBE), and 3 % dimethylaminohexadecyl methacrylate (DMAHDM) and 20 % calcium phosphate nanoparticles (NACP) were added. Mechanical properties, polymerization shrinkage stress, and degree of conversion were evaluated. The growth of Streptococcus mutans (S. mutans) on enamel slabs with different composites was assessed. Ca and P ion releases and monomer cytotoxicity were measured. RESULTS: Composite with DMAHDM and NACP had flexural strength of 84.9 ±â€¯10.3 MPa (n = 6), matching that of a commercial control composite. Adding 3 % DMAHDM did not negatively affect the composite ion release. Under S. mutans biofilm, the marginal enamel hardness was 1.2 ±â€¯0.1 GPa for the remineralizing and antibacterial group, more than 2-fold the 0.5 ±â€¯0.07 GPa for control (p < 0.05). The polymerization shrinkage stress of the new composite was 40 % lower than that of traditional composite control (p < 0.05). The new monomers had fibroblast viability similar to that of traditional monomer control (p > 0.1). CONCLUSION: A novel low-shrinkage-stress nanocomposite was developed with remineralizing and antibacterial properties. This new composite is promising to inhibit recurrent caries at the restoration margins by reducing polymerization stress and protecting enamel hardness.


Assuntos
Biofilmes , Nanocompostos , Antibacterianos/farmacologia , Fosfatos de Cálcio/farmacologia , Resinas Compostas/farmacologia , Esmalte Dentário , Metacrilatos/farmacologia , Streptococcus mutans
10.
Colloids Surf B Biointerfaces ; 188: 110774, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31945630

RESUMO

A new type of photocurable resin composite containing nano-MgO was synthesized in order to reduce the occurrence of secondary caries. Different mass ratios (0 %, 1 %, 2 %, 4 %, 8 %) of nano-MgO were added into resin composites. The antibacterial properties of nano-MgO powder and modified resin composites against Streptococcus mutans (S. mutans) were detected by antibacterial ring test and film contact test, respectively. Compressive strength (CS) and wear resistance were determined by a universal testing machine and an abrasion test machine. The results indicated that antibacterial activity and wear resistance of resin composites containing nano-MgO were superior to the control group (p < 0.05). The antibacterial rate reached as high as 99.4 % when the mass ratio of nano-MgO was 8 %. However, the CS values tended to decline as the content of nano-MgO increase. Hence, the addition of nano-MgO showed excellent antibacterial property to resin composites and enhanced wear resistance, but was detrimental to their mechanical properties.


Assuntos
Antibacterianos/farmacologia , Resinas Compostas/farmacologia , Luz , Óxido de Magnésio/farmacologia , Nanopartículas/química , Antibacterianos/química , Resinas Compostas/química , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Óxido de Magnésio/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície
11.
Technol Health Care ; 28(2): 165-173, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31594266

RESUMO

BACKGROUND: The antibacterial properties are beneficial and desired for dental restorative composite materials. The incorporation of various antimicrobial agents into resin composites may compromise their physical and mechanical properties hence limiting their applications. OBJECTIVE: The aim of the current study is to evaluate the antibacterial activity and the hardness of microhybrid and flowable resin based composites (RBCs) modified using novel antimicrobial agent chitosan (CS). METHODS: The antibacterial activity of microhybrid and flowable RBCs modified with 0, 0.25, 0.5 and 1% w/w chitosan (CS) against Actinomyces viscous bacteria was explored using agar diffusion test and direct contact methods. The hardness of control and experimental RBCs was determined by Vickers hardness (VH) tester. RESULTS: The results revealed that control and experimental flowable and microhybrid RBCs did not demonstrate growth inhibition zone in the lawn growth of Actinomyces viscous. The direct contact test revealed that colony forming unit (CFU) count of Actinomyces viscous was comparable among the experimental and control materials. The flowable RBCs containing 1% CS had significantly higher VH compared to control and other experimental flowable RBC groups. The microhybrid RBCs consisting of 0.50% CS exhibited significantly higher VH compared to experimental microhybrid RBC group containing 1% CS.


Assuntos
Antibacterianos/farmacologia , Quitosana/química , Quitosana/farmacologia , Resinas Compostas/química , Resinas Compostas/farmacologia , Técnicas Bacteriológicas , Materiais Dentários , Dureza , Humanos , Teste de Materiais , Propriedades de Superfície
12.
J Appl Oral Sci ; 27: e20180262, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31508789

RESUMO

The incorporation of antimicrobials in the composites as an attempt to reduce bacterial adhesion without jeopardizing mechanical properties is a challenge for Dentistry. OBJECTIVE To evaluate the bacterial adhesion and physical properties of a composite containing the methacrylate triclosan- derivative monomer (TM). METHODOLOGY TM was synthesized and added to an experimental composite. Samples were divided into two groups: Control and TM (13.4 wt%). Antibacterial Activity: Three specimens of each material were prepared and placed on bacterial suspensions of Streptococcus mutans for 1, 5 and 10 days. After these periods the counting of the colonies (log10) was performed. Assays was performed in triplicate. Physical Properties: Three-body Abrasion (TBA): Ten specimens of each material were prepared and stored at 37°C/24 h. The surface roughness (Ra) and hardness (KHN) were analyzed. Next, the specimens were submitted to abrasive wear (30,000 cycles) and re-evaluated for Ra and KHN; Sorption/solubility (SS): cylindrical specimens (n=10) were prepared and weighted. The specimens were immersed in deionized water for 7 days at 37°C and then their weight was verified again. SS were calculated using accepted formulas; Diametral tensile strength (DTS): specimens (n=10) underwent test performed in an Instron universal testing machine at a crosshead speed of 1 mm/min. Data were submitted to appropriate statistical tests according to data distribution and assay (p<0.05). RESULTS Bacterial Adhesion: TM showed a significant reduction on biofilm accumulation in the evaluated periods: 1 day (1.537±0.146); 5 days (2.183±0.138) and 10 days (4.469±0.155) when compared with Control: 1 day (4.954±0.249); 5 days (5.498±0.257) and 10 days (6.306±0.287). Physical Properties: For TBA, SS and DTS no significant difference was found between groups Control and TM. The incorporation of methacrylate triclosan-based monomer in the experimental composite reduce bacterial adhesion of S. mutans and did not affect important polymer properties.


Assuntos
Antibacterianos/química , Resinas Compostas/química , Metacrilatos/química , Triclosan/química , Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Contagem de Colônia Microbiana , Resinas Compostas/farmacologia , Testes de Dureza , Teste de Materiais , Metacrilatos/farmacologia , Valores de Referência , Reprodutibilidade dos Testes , Solubilidade , Streptococcus mutans/efeitos dos fármacos , Propriedades de Superfície , Resistência à Tração , Fatores de Tempo , Escovação Dentária , Triclosan/farmacologia
13.
Mater Sci Eng C Mater Biol Appl ; 104: 109916, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499946

RESUMO

Composite resins (CRs) are widely used as dental restorative materials for caries treatment. They cause problems of secondary caries since Streptococcus mutans stays in the dental plaque, which the surface exists and produces acidic compounds during metabolism. The dental plaque depositions are induced by the protein adsorption on the surface. Therefore, suppression of protein adsorption on the surface of the CRs is important for inhibiting the formation of plaque and secondary caries. In this study we developed a surface treatment to provide an antibiofouling nature to the CRs by chemical reaction with 2-methacryloyloxyethyl phosphorylcholine (MPC) polymers in the oral cavity during dental treatment. To carry out the photochemical reaction on the remaining polymerizable groups of CRs, we synthesized the MPC polymer with a polymerizable group in the side chain. The MPC polymer could bind on the surfaces of the CRs chemically under dental treatment procedures. The treated surface showed significant resistance to oral protein adsorption and bacterial adhesion even when the surface was brushed with a toothbrush. Thus, we concluded that the photochemical reaction of the MPC polymer with the CRs in the oral cavity was good for making an antibiofouling surface and preventing secondary caries.


Assuntos
Resinas Acrílicas/farmacologia , Resinas Compostas/farmacologia , Placa Dentária/prevenção & controle , Metacrilatos/farmacologia , Fosforilcolina/análogos & derivados , Polímeros/farmacologia , Poliuretanos/farmacologia , Incrustação Biológica , Mucinas/metabolismo , Fósforo/análise , Fosforilcolina/farmacologia , Espectroscopia Fotoeletrônica , Polímeros/síntese química , Polímeros/química , Espectroscopia de Prótons por Ressonância Magnética , Silício/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Streptococcus mutans/efeitos dos fármacos , Propriedades de Superfície
14.
Braz Oral Res ; 33: e075, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31432926

RESUMO

Resinous infiltrants are indicated in the treatment of incipient carious lesions, and further development of these materials may contribute to greater control of these lesions. The aim of this study was to analyze the physical and antibacterial properties of experimental infiltrants containing iodonium salt and chitosan. Nine experimental infiltrants were formulated by varying the concentration of the diphenyliodonium salt (DPI) at 0, 0.5 and 1 mol%; and chitosan at 0, 0.12 and 0.25 g%. The infiltrants contained the monomeric base of triethylene glycol dimethacrylate and bisphenol-A dimethacrylate ethoxylate in a 75 and 25% proportion by weight, respectively; 0.5 mol% camphorquinone and 1 mol% ethyl 4-dimethylaminobenzoate. The degree of conversion was evaluated using Fourier transformer infrared spectroscopy, and the flexural strength and elastic modulus using the three-point bending test. Sorption and solubility in water, and antibacterial analysis (minimum inhibitory concentration and minimum bactericidal concentration) were also analyzed. Data was analyzed statistically by two-way ANOVA and Tukey's test (p<0.05), with the exception of the antibacterial test, which was evaluated by visual inspection. In general, the infiltrant group containing 0.5% DPI and 0.12% chitosan showed high values of degree of conversion, higher values of elastic modulus and flexural strength, and lower sorption values in relation to the other groups. Antibacterial activity was observed in all the groups with DPI, regardless of the concentration of chitosan. The addition of DPI and chitosan to experimental infiltrants represents a valid option for producing infiltrants with desirable physical and antibacterial characteristics.


Assuntos
Antibacterianos/química , Quitosana/química , Resinas Compostas/química , Metacrilatos/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Sais/química , Análise de Variância , Antibacterianos/farmacologia , Quitosana/farmacologia , Resinas Compostas/farmacologia , Módulo de Elasticidade , Resistência à Flexão , Lactobacillus acidophilus/efeitos dos fármacos , Cura Luminosa de Adesivos Dentários , Teste de Materiais , Metacrilatos/farmacologia , Testes de Sensibilidade Microbiana , Polietilenoglicóis/farmacologia , Ácidos Polimetacrílicos/farmacologia , Valores de Referência , Reprodutibilidade dos Testes , Sais/farmacologia , Solubilidade , Estatísticas não Paramétricas , Streptococcus mutans/efeitos dos fármacos
15.
J Dent ; 89: 103182, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31430508

RESUMO

OBJECTIVES: To compare the relative effects of cigarette smoke (CS), electronic cigarette (EC), red wine, coffee, and soy sauce on the color of enamel, dentin, and composite resin restorations, as well as the effects of whitening treatments. METHODS: Seventy premolars with composite restorations were exposed to CS, EC aerosol (a novel EC device with MESH™ technology [P4M3 version 1.0, Philip Morris International]), red wine, coffee, and soy sauce for 56 min/day for 15 days. Two whitening sessions with 6% and 35% hydrogen peroxide (H2O2) were performed on the exposed samples. Teeth exposed to CS and EC aerosol were also brushed with whitening toothpaste for 3 weeks. Color match of resin restorations was assessed, and color changes were compared after exposure and after whitening treatments. RESULTS: Discolorations in enamel, dentin, and composite resin were observed in the order of red wine > CS > soy sauce > coffee > EC. Color mismatch between enamel and resin restorations occurred only in red wine and CS groups. Brushing with whitening toothpaste removed discoloration caused by EC aerosol; H2O2 treatments were necessary to eliminate discolorations caused by coffee and soy sauce. Discolorations of dentin and resin restorations could not be completely removed by whitening treatments, and color mismatch remained in teeth exposed to red wine and CS. CONCLUSION: Red wine and CS cause significant tooth discoloration and color mismatch in enamel and resin restorations that are not reversible by whitening treatments. Tooth discoloration associated with EC aerosol was minimal and could be removed by brushing with whitening toothpaste. CLINICAL SIGNIFICANCE: Red wine drinkers and cigarette smokers have increased risks for tooth discoloration and color mismatch between enamel and composite resin restorations. Whitening treatments may not be effective in correcting the color mismatch. Tooth discoloration associated with EC aerosol is minimal.


Assuntos
Resinas Compostas/farmacologia , Peróxido de Hidrogênio/farmacologia , Descoloração de Dente/tratamento farmacológico , Dente/efeitos dos fármacos , Cor , Resinas Compostas/química , Dureza , Humanos , Clareadores Dentários/farmacologia , Descoloração de Dente/patologia
16.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 54(7): 450-455, 2019 Jul 09.
Artigo em Chinês | MEDLINE | ID: mdl-31288324

RESUMO

Objective: To investigate the preventive effect of resin infiltration and adhesive on early erosive enamel wear. Methods: Orthodontic reduction premolars collected from Central Laboratory of Nanjing Stomatological Hospital, Medical School of Nanjing University were used to prepare 70 specimens. Forty samples were divided into eight groups (n=5) and treated with different conditions (pH=1.6, 2.4, 3.2 or 4.0 hydrochloric acid solution, etching time was 30 or 60 s), and the conditions for obtaining early erosive enamel samples were selected. Based on this procedure, thirty early erosive enamel samples were made and divided into three groups: control group, resin infiltration group, and adhesive group. And the treatment of 30 days acid abrasion cycle was carried out. Confocal microscopy was used to measure the thickness changes of enamel or material before and after cycle. Results: Early erosive enamel samples was obtained when pH was 4.0 and etching time was 60 s. After 30 days cycle, the wear of enamel was (29.71±6.72) µm in control group, (5.60±2.24) µm in resin infiltration group and (2.89±1.03) µm in adhesive group. In infiltration group and adhesive group, lower enamel was not affected by the cycle, and the material loss ratios of the infiltration resin group and adhesive group were 0.41±0.14 and 0.29±0.13, respectively. The ratio of material loss was not significantly different (P>0.05). But infiltration group lost (12.95±2.22) µm of enamel during the application of the material. Conclusions: Resin infiltration and adhesive have the same short-term protective effect against early erosive enamel wear. Adhesive has less damage to enamel and better effect.


Assuntos
Adesivos , Resinas Compostas , Esmalte Dentário , Ácido Clorídrico , Erosão Dentária , Adesivos/farmacologia , Dente Pré-Molar , Resinas Compostas/farmacologia , Esmalte Dentário/efeitos dos fármacos , Humanos , Ácido Clorídrico/farmacologia , Erosão Dentária/induzido quimicamente , Erosão Dentária/prevenção & controle
17.
Sci Rep ; 9(1): 10632, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337813

RESUMO

Persistent apical periodontitis, mainly caused by microorganisms infections, represents a critical challenge for endodontists. Dimethylaminododecyl methacrylate (DMADDM) is a well-studied and potent antibacterial agent used in various studies described in the literature. The aim of this study is to develop a novel antibacterial root canal sealer by incorporating DMADDM into EndoREZ and investigate the properties of the resulting material. Different mass fractions (0, 1.25%, 2.5%, and 5%) of DMADDM were incorporated into EndoREZ and the cytotoxicity, apical sealing ability and solubility of the resulting material were evaluated. Furthermore, a direct contact test, determination of colony-forming units, a crystal violet assay, scanning electronic microscopy and live/dead bacteria staining were performed to evaluate the antibacterial effect of the sealer to multispecies bacteria (Enterococcus faecalis, Streptococcus gordonii, Actinomyces naeslundii, and Lactobacillus acidophilus), in planktonic cells or biofilms. Fluorescence in situ hybridization and quantitative real-time polymerase chain reaction were carried out to assess the composition of the multispecies biofilms. No difference on the cytotoxicity, apical sealing ability and solubility between sealers containing DMADDM (1.25%, 2.5%) and EndoREZ (0%) could be determined. However, when the mass fraction of DMADDM increased to 5%, significantly different properties were found compared to the 0% (p < 0.05) group. Moreover, incorporating DMADDM into the sealer could greatly improve the antibacterial properties of EndoREZ. In addition, the composition ratio of E. faecalis could be decreased in multispecies microecology in sealers containing DMADDM. Therefore, a EndoREZ sealer material containing DMADDM could be considered useful in clinical applications for preventing and treating persistent apical periodontitis.


Assuntos
Antibacterianos/farmacologia , Resinas Compostas/farmacologia , Cavidade Pulpar , Metacrilatos/farmacologia , Compostos de Amônio Quaternário/farmacologia , Cimento de Óxido de Zinco e Eugenol/farmacologia , Actinomyces/efeitos dos fármacos , Actinomyces/genética , Animais , Biofilmes/efeitos dos fármacos , Linhagem Celular , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Fibroblastos/efeitos dos fármacos , Humanos , Hibridização in Situ Fluorescente , Lactobacillus acidophilus/efeitos dos fármacos , Lactobacillus acidophilus/genética , Camundongos , Viabilidade Microbiana/efeitos dos fármacos , Periodontite Periapical/prevenção & controle , Reação em Cadeia da Polimerase em Tempo Real , Streptococcus gordonii/efeitos dos fármacos , Streptococcus gordonii/genética
18.
Int. j. morphol ; 37(2): 685-689, June 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1002277

RESUMO

El Theracal TM LC es un cemento silicato de calcio (Ca) modificado con resina (SMCR) que ha demostrado ser un material ideal para el tratamiento dentino-pulpar por su alta tasa de formación de calcio. Los biomateriales por su contenido de Ca tienden a tener un aumento en su biodisponibilidad, estimulando la formación del puente dentario atreves de las células involucradas en la formación de tejidos mineralizados, promoviendo la diferenciación de fibroblastos en odontoblastos y aumentando la actividad de la enzima pirofostasa responsable en la mineralización de la dentina. El presente estudio con el objetivo de evaluar la respuesta inflamatoria a Theracal TM LC subcutáneamente en ratas Wistar. Fueron usados seis ratas cepa Wistar en las cuales se realizaron cuatro bolsillos quirúrgicos subcutáneos. Cada uno de estos bolsillos se determinó como cuadrante distinto, conteniendo los siguientes implantes: 1 Theracal TM LC en tubo polietileno, 2 tubo de polietileno, 3 Theracal TM LC directo y 4 como control. Las muestras histológicas se procesaron y se evaluaron distintos tipos celulares mediante conteo a microscopio de luz a 100X utilizando las tinciones H&E y AT pH 2.3. Los resultados mostraron que existen diferencias significativas en todos los tipos celulares observados durante los diferentes tiempos de exposición. Las diferencias en los tipos celulares observados podrían ser debido al tiempo de exposición al Theracal TM LC, al tubo polietileno y a ambos. El tejido evaluado del implante del tubo polietileno y al tubo polietileno con Theracal TM LC, presentan mayor respuesta inflamatoria, a diferencia en el tejido implantado con Theracal TM LC directamente.


TheraCalTM LC is a resin-modified calcium silicate (Ca) resin (SMCR) that has proven to be an ideal material for dentin-pulp treatment due to its high rate of calcium formation. Biomaterials due to their Ca content tend to have an increase in their bioavailability, stimulating the formation of the dental bridge through the cells involved in the formation of mineralized tissues, promoting the differentiation of fibroblasts in odontoblasts and increasing the activity of the pyrophosphate enzyme responsible in dentin mineralization. The present study aimed to evaluate the inflammatory response to TheracalTM LC subcutaneously in Wistar rats. Six Wistar strain rats were used in which four subcutaneous surgical pockets were made. Each of these pockets was determined as a different quadrant, containing the following implants: 1 TheracalTM LC in polyethylene tube, 2 polyethylene tubes, 3 TheracalTM LC direct and 4 as control. The histological samples were processed, and different cell types were evaluated by light microscopy at 100X using the H&E and AT pH 2.3 stains. The results showed that there are significant differences in all cell types observed during the different exposure times. The differences in the cell types observed could be due to the exposure time to TheracalTM LC, to the polyethylene tube and to both. The evaluated tissue of the polyethylene tube implant and the polyethylene tube with TheracalTM LC present a greater inflammatory response, unlike in the tissue implanted with TheracalTM LC directly.


Assuntos
Animais , Ratos , Compostos de Cálcio/farmacologia , Resinas Compostas/farmacologia , Tela Subcutânea/efeitos dos fármacos , Inflamação , Materiais Biocompatíveis/farmacologia , Ratos Wistar , Silicatos
19.
Dent Traumatol ; 35(3): 199-203, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30933418

RESUMO

BACKGROUND/AIMS: Uncomplicated crown fracture is the most common traumatic dental injury. The International Association of Dental Traumatology has recommended fragment reattachment as the best method for restoring uncomplicated crown fractures of permanent teeth. Dehydration can affect fracture resistance after reattachment. However, a standard protocol for rehydration is still lacking. Hence, the aim of this study was to design a humidification chamber and assess its efficacy for improving the rehydration of tooth fragments and increasing fracture resistance after reattachment. MATERIALS AND METHODS: Sixty mandibular bovine incisors with similar dimensions and free of any structural deformities were fractured and randomized into five groups: Group I, Control Group (sound teeth); Group II (dehydrated for 24 hours); Group III (rehydrated in distilled water for 15 minutes); Group IV (rehydrated in a humidification chamber for 15 minutes); and Group V (restored with composite). A humidification chamber was designed and used for rehydration for 15 minutes in Group IV. Fragments in Group III were immersed in distilled water for 15 minutes. Reattachment procedures and materials remained the same in all groups. Fracture resistance was tested in a universal testing machine, and statistical analysis was done by Stata-14. RESULTS: The Control Group with sound teeth (Group I) exhibited a maximum value of 282 ± 10.32 N, while Group II (fragment reattached without rehydration) had the least fracture resistance, 49.75 ± 5.2 N. Rehydration by means of the humidification chamber protocol (Group IV) resulted in significantly higher fracture resistance (150.54 ± 6.49 N) than in Group III (rehydration by means of immersion). CONCLUSIONS: Fracture resistance after fragment reattachment was significantly affected by the rehydration of fragments for 15 minutes in the humidification chamber. Fragment reattachment after rehydration showed better fracture resistance than the composite restorations.


Assuntos
Colagem Dentária , Coroa do Dente , Fraturas dos Dentes , Animais , Bovinos , Resinas Compostas/farmacologia , Coroas , Colagem Dentária/métodos , Restauração Dentária Permanente , Análise do Estresse Dentário , Hidratação , Humanos , Distribuição Aleatória
20.
Methods Mol Biol ; 1922: 369-377, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30838591

RESUMO

Due to the high failure rates of traditional dental restorations, there is an ongoing effort to develop modified and new restorative biomaterials in dentistry. Being the most commonly used restorative material, most of these efforts primarily aim to improve dental composite. Generally, the main objective of such modifications is to enhance the restorative physical and antimicrobial properties in order to limit micro-leakage and inhibit bacterial biofilm cultivation. Herein, we describe the process of designing a simple in vitro model to assess the physical and antimicrobial properties of novel restorative materials in addition to evaluating their effect on the fragile balance between enamel de- and remineralization.


Assuntos
Anti-Infecciosos/farmacologia , Cárie Dentária/microbiologia , Cárie Dentária/terapia , Materiais Dentários/farmacologia , Streptococcus mutans/efeitos dos fármacos , Animais , Biofilmes/efeitos dos fármacos , Bovinos , Resinas Compostas/farmacologia , Esmalte Dentário/microbiologia , Incisivo/microbiologia , Microscopia Confocal/métodos , Streptococcus mutans/fisiologia
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