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1.
J Appl Oral Sci ; 27: e20180593, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31508792

RESUMO

There is growing evidence that C. albicans is associated with dental caries, but its role on caries development needs to be better clarified. Label="OBJECTIVE">To evaluate at the hard tissue level the effect of C. albicans on the cariogenic potential of S. mutans biofilms focusing on the mineral profile of induced carious lesions. This study also aimed to evaluate the effect of C. albicans on the acidogenic potential of S. mutans biofilms. METHODOLOGY Dual-species (CA+SM) and single-species biofilms (CA or SM) were grown on the surface of enamel slabs in the presence of glucose/sucrose supplemented culture medium for 24, 48 and 72 hours. Demineralization was evaluated through percentage of surface microhardness change (%SMC) and transversal microradiography analysis (ILM and LD) and pH of the spent medium was recorded daily. Data were analyzed by two-way ANOVA followed by Bonferroni correction. RESULTS%SMC was statistically different among the biofilms at each time point being the highest for SM biofilms and the lowest for CA biofilms which also differed from CA+SM biofilms [SM (24 h: 47.0±7.3; 48 h: 66.3±8.3; 72 h: 75.4±3.9); CA (24 h: 7.3±3.3; 48 h: 7.1±6.4; 72 h: 6.6±3.6); CA+SM (24 h: 35.9±7.39.1; 48 h: 47.2±9.5; 72 h: 47.6±9.5)]. pH of spent medium was statistically lower for SM biofilms compared to the other biofilms at each time point and remained constant over time while pH values increased from 24 to 72 h for both CA and CA+SM biofilms [SM (24 h: 4.4±0.1; 48 h: 4.4±0.1; 72 h: 4.5±0.1); CA (24 h: 6.9±0.3; 48 h: 7.2±0.2; 72 h: 7.5±0.2); CA+MS (24 h: 4.7±0.2; 48 h: 5.1±0.1; 72 h: 6.1±0.6)]. IML and LD for SM biofilms increased over time while no difference was observed from 24 to 72 h for the other biofilms. CONCLUSIONS The present data suggest that C. albicans has low enamel demineralization potential and the presence of C. albicans can reduce both the cariogenic and acidogenic potentials of S. mutans biofilms.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida albicans/fisiologia , Esmalte Dentário/microbiologia , Streptococcus mutans/metabolismo , Desmineralização do Dente/microbiologia , Ácidos/metabolismo , Animais , Bovinos , Contagem de Colônia Microbiana , Esmalte Dentário/química , Testes de Dureza , Concentração de Íons de Hidrogênio , Microrradiografia/métodos , Valores de Referência , Propriedades de Superfície , Fatores de Tempo
2.
Arch Oral Biol ; 104: 133-140, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31202148

RESUMO

OBJECTIVES: The present study aimed to investigate if bovine milk or milk protein isolates, respectively, alter the ultrastructure of thein situ pellicle and might therefore have an influence on oral health. METHODS: In situ pellicle samples were formed on bovine enamel slabs exposed in the oral cavity of three subjects for 6, 30, 60 or 120 min. After 3 min of pellicle formation, mouthrinses were performed for 3 min with (non-)homogenized UHT- or fresh milk (0.3% or 3.8% fat), 30% UHT-treated cream or different types of casein- or milk protein isolates containing preparations. The specimens were removed after the exposure times and transmission electron microscopy (TEM) was performed. Native pellicle samples served as controls. RESULTS: Topical ultrastructural pellicle modifications were detected after mouthrinses with all types of homogenized UHT- or fresh milk and after the application of a 3% native casein micelles containing experimental solution. Atypical globular protein structures, identified as casein micelles, were temporarily adsorbed onto the pellicle. They were closely associated with lipid droplets. Furthermore, the mouthrinses occasionally affected the morphology of salivary bacteria. However, no notable ultrastructural alterations remained after 120 min of pellicle formation. CONCLUSION: For the first time, bovine milk- and micellar casein-induced pellicle modifications were revealed by TEM. The adsorption of micellar casein is possibly due to its molecular interactions. CLINICAL SIGNIFICANCE: Bovine milk or micellar caseins provide some potential for the development of preventive strategies against bacterial biofilm formation or erosive processes at the tooth surface.


Assuntos
Biofilmes , Película Dentária , Proteínas do Leite , Leite , Erosão Dentária , Animais , Bovinos , Esmalte Dentário/microbiologia , Película Dentária/efeitos dos fármacos , Humanos , Boca/microbiologia
3.
J Appl Oral Sci ; 27: e20180514, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31166551

RESUMO

OBJECTIVES: The aim of this study was to assess the effect of Myracrodruon urundeuva All. and Qualea grandiflora Mart. leaves hydroalcoholic extracts on viability and metabolism of a microcosm biofilm and on enamel demineralization prevention. METHODOLOGY: Microcosm biofilm was produced on bovine enamel using inoculum from pooled human saliva mixed with McBain saliva, under 0.2% sucrose exposure, for 14 days. The biofilm was daily-treated with the extracts for 1 min. At the end, it was analyzed with respect to viability by fluorescence, CFU counting and extracellular polysaccharides (phenol-sulphuric acid colorimetric assay) and lactic acid (enzymatic assay) production. The demineralization was measured by TMR. The data were compared using ANOVA or Kruskal-Wallis (p<0.05). RESULTS: M. urundeuva All. at 100, 10 and 0.1 µg/mL and Q. grandiflora Mart. at 100 and 0.1 µg/mL reduced biofilm viability similarly to positive control (chlorhexidine) and significantly more than the negative-vehicle control (35% ethanol). M. urundeuva at 1000, 100 and 0.1 µg/mL were able to reduce both lactobacilli and mutans streptococci CFU counting, while Q. grandiflora (1000 and 1.0 µg/mL) significantly reduced mutans streptococci CFU counting. On the other hand, the natural extracts were unable to significantly reduce extracellular polysaccharides and lactic acid productions neither the development of enamel carious lesions. CONCLUSIONS: The extracts showed antimicrobial properties on microcosm biofilm, however, they had no effect on biofilm metabolism and caries protection.


Assuntos
Anacardiaceae/química , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Myrtales/química , Extratos Vegetais/farmacologia , Desmineralização do Dente/prevenção & controle , Animais , Cariostáticos/farmacologia , Bovinos , Contagem de Colônia Microbiana , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/microbiologia , Ácido Láctico/metabolismo , Lactobacillus/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Microrradiografia/métodos , Folhas de Planta/química , Polissacarídeos Bacterianos/metabolismo , Reprodutibilidade dos Testes , Saliva/química , Streptococcus mutans/efeitos dos fármacos
4.
Methods Mol Biol ; 1922: 357-368, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30838590

RESUMO

Caries lesions result from the interaction between dental biofilm and sugars. Since the biofilm is an important component in the etiology of the disease, biofilm models have been developed to study the cariogenicity of dietary sugars, as well as the anticaries effect of substances. Two of such models, termed as "static" or "continuous flow," are described in details here together with their advantages, limitations, and applications.


Assuntos
Biofilmes , Cárie Dentária/microbiologia , Streptococcus mutans/fisiologia , Animais , Técnicas Bacteriológicas/instrumentação , Técnicas Bacteriológicas/métodos , Bovinos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Meios de Cultura/química , Meios de Cultura/metabolismo , Cárie Dentária/metabolismo , Esmalte Dentário/microbiologia , Desenho de Equipamento , Humanos , Boca/microbiologia , Açúcares/metabolismo
5.
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
6.
Caries Res ; 53(1): 10-15, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29874637

RESUMO

It has been suggested that fluoride binding to dental biofilm is enhanced when more bacterial calcium binding sites are available. However, this was only observed at high calcium and fluoride concentrations (i.e., when CaF2 precipitation may have occurred). We assessed fluoride binding to Streptococcus mutans pellets treated with calcium and fluoride at concentrations allowing CaF2 precipitation or not. Increasing calcium concentration resulted in a linear increase (p < 0.01) in fluoride concentration only in the pellets in which CaF2 precipitated. The results suggest that CaF2 precipitation, rather than bacterially bound fluoride, is responsible for the increase in fluoride binding to dental biofilm with the increase in calcium availability.


Assuntos
Biofilmes/efeitos dos fármacos , Cálcio/química , Cariostáticos/química , Esmalte Dentário/microbiologia , Fluoretos/química , Streptococcus mutans/fisiologia , Análise de Variância , Fluoreto de Cálcio/química , Precipitação Química , Cárie Dentária/microbiologia , Cárie Dentária/prevenção & controle , Sinergismo Farmacológico , Humanos , Concentração Osmolar , Análise de Regressão
7.
J Appl Oral Sci ; 27: e20180042, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30540069

RESUMO

OBJECTIVES: The use of antimicrobial agents is an efficient method to prevent dental caries. Also, nanometric antibacterial agents with wide antibacterial spectrum and strong antibacterial effects can be applied for prevention of dental caries. The aim of this study was to evaluate the inhibitory effect of reduced graphene oxide-silver nanoparticles (rGO/Ag) composite on the progression of artificial enamel caries in a Streptococcus mutans biofilm model. MATERIAL AND METHODS: Enamel specimens from bovine incisors were divided into eight treatment groups (n = 13), as follows: group 1 was inoculated with S. mutans grown in Brain Heart Infusion containing 1% sucrose (1% BHIS), as negative control; groups 2-4 were inoculated with S. mutans grown in the presence of different rGO/Ag concentrations (0.08, 0.12, 0.16 mg/mL) + 1% BHIS; group 5-7 were inoculated with S. mutans grown in the presence of different agents (0.16 mg/mL reduced graphene oxide, 0.16 mg/mL silver nanoparticles, 10 ppm NaF) + 1% BHIS; group 8 was mixed with 1% BHIS, without inoculation. Artificial enamel carious lesions were produced by S. mutans biofilm model for 7 days. Confocal laser scanning microscopy and atomic force microscopy were used to analyze roughness and morphology of the enamel surface. Polarized light microscopy and confocal laser scanning microscopy were employed to measure the lesion depth and the relative optical density (ROD) of the demineralized layer. RESULTS: Compared with the control groups, the rGO/Ag groups showed: (a) reduced enamel surface roughness; (b) much smoother and less eroded surfaces; (c) shallower lesion depth and less mineral loss. CONCLUSION: As a novel composite material, rGO/Ag can be a promising antibacterial agent for caries prevention.


Assuntos
Antibacterianos/farmacologia , Cárie Dentária/prevenção & controle , Esmalte Dentário/efeitos dos fármacos , Grafite/farmacologia , Nanopartículas Metálicas , Prata/farmacologia , Streptococcus mutans/efeitos dos fármacos , Animais , Cariostáticos/farmacologia , Bovinos , Cárie Dentária/microbiologia , Esmalte Dentário/microbiologia , Progressão da Doença , Grafite/química , Nanopartículas Metálicas/química , Microscopia Confocal , Nanocompostos/química , Valores de Referência , Reprodutibilidade dos Testes , Prata/química , Propriedades de Superfície
8.
Braz Oral Res ; 32: e109, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30328901

RESUMO

This study investigated the effect of human milk, alone and associated with sucrose, in the cariogenicity of biofilms in a microcosm biofilm model and compared with the cariogenicity of sucrose and bovine milk. Microcosm biofilms were grown in enamel discs in 24-well plates. Six growth conditions were studied: DMM (chemically defined artificial saliva - negative control), DMM with 1% of sucrose (DMM+s) (positive control), human milk with DMM, human milk with DMM+s, bovine milk with DMM, and bovine milk with DMM+s. After 5 days, the outcome variables surface hardness change (%SHC), microbiological composition of biofilms, and pH of supernatant were analyzed. All groups had significantly lower hardness loss compared to the DMM group with 1% of sucrose. Human and bovine milk associated with sucrose showed higher hardness loss. The supernatant pH values after 6 hours of different treatments were similar for the groups sucrose and human milk associated with sucrose (p>0.05). After 18 hours at rest in pure DMM, an increase in the pH of the supernatant was observed. Higher values of total microorganisms count were found for sucrose and bovine milk groups compared to the group supplemented only by DMM. Bovine milk group showed greater amount of total aciduric microorganisms in comparison to human milk group. Within the limits of this study, it can be infered that both human and cow milks have some cariogenic potential, although differing from sucrose in terms of mineral loss.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cariogênicos/efeitos adversos , Cárie Dentária/microbiologia , Esmalte Dentário/microbiologia , Leite Humano/microbiologia , Sacarose/efeitos adversos , Análise de Variância , Animais , Aleitamento Materno/efeitos adversos , Cariogênicos/química , Bovinos , Contagem de Colônia Microbiana , Dieta Cariogênica/efeitos adversos , Testes de Dureza , Humanos , Concentração de Íons de Hidrogênio , Leite/microbiologia , Leite Humano/química , Valores de Referência , Fatores de Risco , Saliva/microbiologia , Sacarose/química , Propriedades de Superfície , Fatores de Tempo
9.
Photomed Laser Surg ; 36(12): 660-666, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30260744

RESUMO

Objective: To determine surface roughness caused by Er:YAG laser irradiation and its effect on the increase in bacterial adhesion. Background: Er:YAG laser was proposed as a strategic device to reduce caries by its ability to generate chemical and structural changes in tooth enamel; in turn, it produces undesirable effects on the tooth surface that could increase its roughness and allow a greater accumulation of microorganisms. Methods: Eighty-four samples of human enamel were divided into seven groups (n = 12): G1_control (no laser irradiation); G2_100/H2O, G3_200/H2O, and G4_300/H2O were irradiated with Er:YAG laser (12.7, 25.5, and 38.2 J/cm2, respectively) under water irrigation. In addition, G5_100, G6_200, and G7_300 were irradiated with the energy densities described above and no water irrigation. Surface roughness measurements were recorded before and after treatment using a profilometer. Afterward, three samples per group were incubated in a microorganism suspension for the tetrazolium salt (XTT) assay. Biofilm morphology was observed using scanning electron microscopy and confocal laser scanning microscope. One-way analysis of variance and t-tests were performed for statistical analysis (p < 0.05). Results: There were no statistically significant differences in roughness values in the G5_100 group before and after treatment, but there were statistically significant differences observed in the other groups evaluated (p < 0.05). No significant differences in adhesion of both strains were detected in irradiated groups compared with G1_control. Conclusions: The increase in roughness on dental enamel surfaces was proportional to the irradiation conditions. However, the increase in surface roughness caused by Er:YAG laser irradiation did not affect Streptococcus mutans and S. sanguinis adhesion.


Assuntos
Esmalte Dentário/microbiologia , Lasers de Estado Sólido , Streptococcus mutans/fisiologia , Streptococcus/fisiologia , Aderência Bacteriana , Biofilmes , Humanos , Técnicas In Vitro , Propriedades de Superfície
10.
Sci Rep ; 8(1): 14202, 2018 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-30242260

RESUMO

Caries is associated with shifts of microbiota in dental biofilms and primarily driven by frequent sucrose consumption. Data on environmentally induced in vivo microbiota shifts are scarce therefore we investigated the influence of frequent sucrose consumption on the oral biofilm. Splint systems containing enamel slabs were worn for 3 × 7 days with 7-day intervals to obtain oral biofilm samples. After a three-month dietary change of sucking 10 g of sucrose per day in addition to the regular diet, biofilm was obtained again at the end of the second phase. The microbiota was analysed using Illumina MiSeq amplicon sequencing (v1-v2 region). In addition, roughness of the enamel surface was measured with laser scanning microscopy. The sucrose phase resulted in significant differences in beta-diversity and significantly decreased species richness. It was marked by a significant increase in abundance of streptococci, specifically Streptococcus gordonii, Streptococcus parasanguinis and Streptococcus sanguinis. Enamel surface roughness began to increase, reflecting initial impairment of dental enamel surface. The results showed that frequent sucrose consumption provoked compositional changes in the microbiota, leading to an increase of non-mutans streptococci, hence supporting the extended ecological plaque hypothesis and emphasizing the synergy of multiple bacterial species in the development of caries.


Assuntos
Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Microbiota/efeitos dos fármacos , Boca/microbiologia , Sacarose/efeitos adversos , Adulto , Cárie Dentária/microbiologia , Esmalte Dentário/microbiologia , Placa Dentária/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Streptococcus/efeitos dos fármacos , Adulto Jovem
11.
Sci Rep ; 8(1): 14010, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30228377

RESUMO

Dental caries is caused by acids released from bacterial biofilms. However, the in vivo formation of initial biofilms in relation to caries remains largely unexplored. The aim of this study was to compare the oral microbiome during the initial phase of bacterial colonization for individuals with (CC) and without (NC) cavitated dentin caries lesions. Bovine enamel slabs on acrylic splints were worn by the volunteers (CC: 14, NC: 13) for in situ biofilm formation (2 h, 4 h, 8 h, 1 ml saliva as reference). Sequencing of the V1/V2 regions of the 16S rRNA gene was performed (MiSeq). The relative abundances of individual operational taxonomic units (OTUs) were compared between samples from the CC group and the NC group. Random forests models were furthermore trained to separate the groups. While the overall heterogeneity did not differ substantially between CC and NC individuals, several individual OTUs were found to have significantly different relative abundances. For the 8 h samples, most of the significant OTUs showed higher relative abundances in the CC group, while the majority of significant OTUs in the saliva samples were more abundant in the NC group. Furthermore, using OTU signatures enabled a separation between both groups, with area-under-the-curve (AUC) values of ~0.8. In summary, the results suggest that initial oral biofilms provide the potential to differentiate between CC and NC individuals.


Assuntos
Biofilmes/crescimento & desenvolvimento , Biomarcadores/análise , Cárie Dentária/microbiologia , Esmalte Dentário/microbiologia , Microbiota/genética , Boca/microbiologia , Saliva/microbiologia , Adulto , Animais , Estudos de Casos e Controles , Bovinos , Cárie Dentária/genética , Cárie Dentária/patologia , Esmalte Dentário/metabolismo , Esmalte Dentário/patologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Adulto Jovem
12.
PLoS One ; 13(9): e0202262, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30192766

RESUMO

INTRODUCTION: Micro- or nano-topography can both provide antimicrobial properties and improve osseointegration of dental implant titanium surfaces. Laser treatment is one of the best surface microtexturing techniques. The aim of this study was to evaluate in vitro and in situ biofilm formation on a laser-treated titanium surface, comparing it with two conventional surfaces, machined and grit-blasted. METHODS: For the in vitro experiment, an oral microcosm biofilm model was developed on the surface of titanium disks and reference human enamel using a bioreactor for 48 h. For the in situ experiment, titanium implants with laser-treated, machined and grit-blasted surfaces were mounted on intraoral trays and worn by ten volunteers for 48 h. Biofilm formation was quantitatively evaluated, and surfaces were analyzed using confocal laser scanning microscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. RESULTS­IN VITRO STUDY: Biofilm structures with a prevalence of viable cells covered most of the machined, grit-blasted and human enamel surfaces, whereas less dense biofilm structures with non-confluent microcolonies were observed on the laser-treated titanium. Laser-treated titanium showed the lowest biofilm formation, where microorganisms colonized the edges of the laser-created pits, with very few or no biofilm formation observed inside the pits. RESULTS­IN SITU STUDY: The biofilm formation pattern observed was similar to that in the in vitro experiment. Confocal laser scanning microscopy showed complete coverage of the implant threads, with mostly viable cells in grit-blasted and machined specimens. Unexpectedly, laser-treated specimens showed few dead microbial cells colonizing the bottom of the threads, while an intense colonization was found on the threading sides. CONCLUSION: This data suggests that laser-created microtopography can reduce biofilm formation, with a maximum effect when the surface is blasted orthogonally by the laser beam. In this sense the orientation of the laser beam seems to be relevant for the biological interaction with biofilms.


Assuntos
Biofilmes/crescimento & desenvolvimento , Implantes Dentários , Lasers , Boca/microbiologia , Titânio/química , Biofilmes/efeitos dos fármacos , Esmalte Dentário/microbiologia , Humanos , Microscopia Confocal , Microscopia Eletrônica de Varredura , Osseointegração/efeitos dos fármacos , Propriedades de Superfície , Titânio/farmacologia
13.
PLoS One ; 13(9): e0203717, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30192874

RESUMO

BACKGROUND: Most electronic-cigarette liquids contain propylene glycol, glycerin, nicotine and a wide variety of flavors of which many are sweet. Sweet flavors are classified as saccharides, esters, acids or aldehydes. This study investigates changes in cariogenic potential when tooth surfaces are exposed to e-cigarette aerosols generated from well-characterized reference e-liquids with sweet flavors. METHODS: Reference e-liquids were prepared by combining 20/80 propylene glycol/glycerin (by volume fraction), 10 mg/mL nicotine, and flavors. Aerosols were generated by a Universal Electronic-Cigarette Testing Device (49.2 W, 0.2 Ω). Streptococcus mutans (UA159) were exposed to aerosols on tooth enamel and the biological and physiochemical parameters were measured. RESULTS: E-cigarette aerosols produced four-fold increase in microbial adhesion to enamel. Exposure to flavored aerosols led to two-fold increase in biofilm formation and up to a 27% decrease in enamel hardness compared to unflavored controls. Esters (ethyl butyrate, hexyl acetate, and triacetin) in e-liquids were associated with consistent bacteria-initiated enamel demineralization, whereas sugar alcohol (ethyl maltol) inhibited S. mutans growth and adhesion. The viscosity of the e-liquid allowed S. mutans to adhere to pits and fissures. Aerosols contained five metals (mean ± standard deviation): calcium (0.409 ± 0.002) mg/L, copper (0.011 ± 0.001) mg/L, iron (0.0051 ± 0.0003) mg/L, magnesium (0.017 ± 0.002) mg/L, and silicon (0.166 ± 0.005) mg/L. CONCLUSIONS: This study systematically evaluated e-cigarette aerosols and found that the aerosols have similar physio-chemical properties as high-sucrose, gelatinous candies and acidic drinks. Our data suggest that the combination of the viscosity of e-liquids and some classes of chemicals in sweet flavors may increase the risk of cariogenic potential. Clinical investigation is warranted to confirm the data shown here.


Assuntos
Cárie Dentária/induzido quimicamente , Sistemas Eletrônicos de Liberação de Nicotina , Aromatizantes/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Cárie Dentária/microbiologia , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/microbiologia , Humanos , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/fisiologia , Propriedades de Superfície
14.
Nat Commun ; 9(1): 3713, 2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30213949

RESUMO

The use of natural substance to ward off microbial infections has a long history. However, the large-scale production of natural extracts often reduces antibacterial potency, thus limiting practical applications. Here we present a strategy for converting natural organosulfur compounds into nano-iron sulfides that exhibit enhanced antibacterial activity. We show that compared to garlic-derived organosulfur compounds nano-iron sulfides exhibit an over 500-fold increase in antibacterial efficacy to kill several pathogenic and drug-resistant bacteria. Furthermore, our analysis reveals that hydrogen polysulfanes released from nano-iron sulfides possess potent bactericidal activity and the release of polysulfanes can be accelerated by the enzyme-like activity of nano-iron sulfides. Finally, we demonstrate that topical applications of nano-iron sulfides can effectively disrupt pathogenic biofilms on human teeth and accelerate infected-wound healing. Together, our approach to convert organosulfur compounds into inorganic polysulfides potentially provides an antibacterial alternative to combat bacterial infections.


Assuntos
Antibacterianos/química , Biofilmes/efeitos dos fármacos , Alho/química , Proteínas com Ferro-Enxofre/química , Sulfetos/química , Compostos de Enxofre/química , Células 3T3 , Compostos Alílicos/química , Animais , Antioxidantes/química , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Cálcio/química , Sobrevivência Celular , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/microbiologia , Dentina/química , Farmacorresistência Bacteriana , Fibroblastos/metabolismo , Humanos , Queratinócitos/citologia , Malondialdeído/química , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/química , Espécies Reativas de Oxigênio , Streptococcus mutans , Dente/efeitos dos fármacos , Dente/microbiologia , Cicatrização
15.
Photodiagnosis Photodyn Ther ; 24: 256-261, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30157462

RESUMO

Photodynamic therapy (PDT) can be used for the control of oral pathogens and different photosensitizers (PS) have been investigated. This study evaluated the efficacy of PDT against Streptococcus mutans biofilms using two second-generation PS derived from chlorin: Photoditazine® (PDZ) and Fotoenticine® (FTC). These PS were compared to methylene blue (MB), a dye with proven antimicrobial activity against S. mutans. Suspensions of S. mutans were cultured in contact with bovine tooth disks for biofilm formation. After 48 h, the biofilms were treated with PDZ (0.6 mg/mL), FTC (0.6 mg/mL) or MB (1 mg/mL) and submitted to laser irradiation (660 nm, 50 mW/cm2). The biofilms were quantified by the determination of CFU/mL count and analyzed by scanning electron microscopy (SEM). All PS used for PDT reduced the number of S. mutans, with a statistically significant difference compared to the untreated groups. PDT achieved microbial reductions of 4 log with MB and 6 log with PDZ, while the use of FTC resulted in the complete elimination of S. mutans biofilms. SEM analysis confirmed the CFU/mL results, showing that all PS, particularly FTC, were able to detach the biofilms and to eliminate the bacteria. In conclusion, PDT mediated by chlorin-type PS exhibited greater antimicrobial activity against S. mutans than MB-mediated PDT, indicating that these PS can be useful for the control of dental caries.


Assuntos
Biofilmes/efeitos dos fármacos , Esmalte Dentário/efeitos dos fármacos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Streptococcus mutans/efeitos dos fármacos , Animais , Bovinos , Esmalte Dentário/microbiologia , Glucosamina/análogos & derivados , Glucosamina/farmacologia , Lasers Semicondutores , Azul de Metileno/farmacologia , Células-Tronco
16.
J Natl Med Assoc ; 110(5): 486-490, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30129510

RESUMO

BACKGROUND: Dental caries is a big public health problem which is prevalent in the highest degree worldwide, especially in lower socioeconomic levels. This study aims to investigate the anti-caries effects of Curcumin in Turmeric on the caries model of enamel under laboratory conditions. METHODS: In order to make a reliable model of caries, a Streptococcus mutans (ATCC 3568) bacterium was used. The biofilm was created on enamel slabs in 5 days. There were 5 groups of slabs. In order to create Cariogenic conditions, the slabs were exposed to Sucrose 10% three times a day and then, it was exposed to different concentrations of Curcumin (5, 10, 20 mg/ml). The slabs of one group were exposed to the normal saline after the exposure to Sucrose and called positive caries control group; and the other group was exposed to normal saline in each time of exposure which was called negative caries control groups. Environment PH was measured by PH meter two times in a day. After the laboratory phase, the slabs were washed and dried and Vickers hardness test was used to determine the superficial hardness and then the decrease rate of superficial hardness (SHL%) was measured by the approved formula. SPSS version 20 was used to analyse the data. Then, to analyse the data, One-way ANOVA with 95% confidence, Kolmogorov - Smirnov, and Tukey test was used. RESULTS: The present study showed that Curcumin can have anti caries effect at the most level even in the least level of concentration used in this study (5 mg/ml). With regard to changes in PH of environment, we can declare that Curcumin results in reducing the dental caries by restraining the bacterial activity. CONCLUSIONS: Regarding that these results were received in laboratory conditions, further studies are needed.


Assuntos
Cariostáticos/farmacologia , Curcumina/farmacologia , Cárie Dentária/prevenção & controle , Esmalte Dentário/efeitos dos fármacos , Cariostáticos/uso terapêutico , Curcumina/uso terapêutico , Esmalte Dentário/microbiologia , Humanos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Streptococcus mutans/efeitos dos fármacos , Sacarose , Desmineralização do Dente/prevenção & controle
17.
Photochem Photobiol ; 94(6): 1240-1248, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29923618

RESUMO

This study aimed to evaluate the use of antimicrobial photodynamic therapy (aPDT) as an adjunct for minimally invasive treatment (partial removal of carious tissue-PRCT) of deciduous carious tissue evaluating its efficacy in reducing microorganisms. For that, a clinical study was design including children with deciduous molars with active deep caries lesions (DCL). PRCT was performed and remaining dentin was treated with 100 µg mL-1 methylene blue solution (5 min) and than irradiated with a low power laser emitting red light (InGaAIP-indium gallium aluminum phosphide; λ = 660 nm; 100 mW; 300 J cm-2 ; 90 s; 9 J). The colony forming units (CFU) count after PRCT and after PRCT + aPDT/mg of dentin were compared for total microorganisms, including Candida spp., the mutans streptococci group, Streptococcus spp. and Lactobacillus spp. The dentin was classified (color, consistency and humidity). The microbial reduction varied from 69.88% to 86.29% and was significantly observed for total microorganisms, mutans streptococci, Streptococcus spp. and Lactobacillus spp (P < 0.001). The dentin type did not influence reduction of microorganisms (P > 0.05). The aPDT presents a promising future for clinical use as an adjunct for the reduction of microorganisms in PRCT of DCL in all kinds of dentin.


Assuntos
Cárie Dentária/tratamento farmacológico , Azul de Metileno/administração & dosagem , Dente Molar/efeitos dos fármacos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Dente Decíduo/efeitos dos fármacos , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Criança , Pré-Escolar , Cárie Dentária/microbiologia , Cárie Dentária/cirurgia , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/microbiologia , Esmalte Dentário/cirurgia , Dentina/efeitos dos fármacos , Dentina/microbiologia , Dentina/cirurgia , Feminino , Humanos , Lactobacillus/efeitos dos fármacos , Lactobacillus/crescimento & desenvolvimento , Lasers , Luz , Masculino , Azul de Metileno/metabolismo , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Dente Molar/microbiologia , Dente Molar/cirurgia , Fármacos Fotossensibilizantes/metabolismo , Streptococcus/efeitos dos fármacos , Streptococcus/crescimento & desenvolvimento , Dente Decíduo/microbiologia , Dente Decíduo/cirurgia , Resultado do Tratamento
18.
Colloids Surf B Biointerfaces ; 167: 531-537, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29730574

RESUMO

Water-soluble, linear polymers with high-acid functionality are commonly used in oral care formulations to provide benefits such as bioactive complexation and delivery, as well as inhibition of the bacteria deposition and colonization, commonly referred to as 'anti-attachment'. Unfortunately, structure-activity relationship (SAR) studies of these polymers are scarce, thus, a systematic approach to design polymers with a desired property (e.g. anti-attachment) is limited. Multifunctional anti-attachment amphiphilic molecules (AMs) featuring a sugar backbone, hydrophobic arms, a poly(ethylene glycol) tail, and a chemical anchor effectively deposited on soft ceramic surfaces and reduced bacterial adhesion. The chemical compositions of the AMs were fine-tuned to better coordinate with dental enamel surfaces and prevent bacterial colonization. A graft-to approach was used to investigate the effect of the chemical anchor on AM deposition and retention. The chemical composition, absorption/desorption, and wettability properties of the bioactives and bioactive-coated surfaces were investigated using nuclear magnetic resonance, X-ray photon spectroscopy, quartz crystal microbalance, and contact angle. In addition, the ability of the AMs to provide anti-bacterial attachment on a simulated enamel surface was evaluated in vitro using bacterial repulsion assays. The SAR between surface retention and anti-attachment properties of the AMs demonstrates the feasibility and tunability of using these polymers as bioactive agents that provide anti-attachment benefits on dental enamel surfaces.


Assuntos
Bactérias/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Durapatita/metabolismo , Polímeros/farmacologia , Bactérias/crescimento & desenvolvimento , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/microbiologia , Durapatita/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Espectroscopia Fotoeletrônica , Polietilenoglicóis/química , Polímeros/química , Técnicas de Microbalança de Cristal de Quartzo , Relação Estrutura-Atividade , Propriedades de Superfície , Molhabilidade
19.
Arch Oral Biol ; 90: 138-143, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29614462

RESUMO

OBJECTIVE: Two factors for secondary caries formation were evaluated using an artificial biofilm model, saliva as additive in culture medium and bonding procedures of composite materials for artificial gap creation. DESIGN: Standardized cavities were prepared in bovine tooth samples (n = 44), treated with two different bonding pretreatments, restored and after artificial ageing incubated with Streptococcus mutans in a Mueller-Hinton-Broth-Sugar medium with or without human saliva for seven days. Secondary caries formation was analyzed using confocal laser scanning microscopy and transversal microradiography. RESULTS: Lesions were significantly pronounced in groups using saliva, but were not influenced by the bonding pretreatments. CONCLUSIONS: The results indicate that the addition of saliva, but not the type of bonding procedure influences the outcome in the present biofilm-based secondary caries model.


Assuntos
Biofilmes , Cárie Dentária/microbiologia , Saliva , Streptococcus mutans/fisiologia , Animais , Aderência Bacteriana , Bovinos , Resinas Compostas/química , Cárie Dentária/diagnóstico por imagem , Cárie Dentária/etiologia , Esmalte Dentário/diagnóstico por imagem , Esmalte Dentário/microbiologia , Esmalte Dentário/patologia , Adesivos Dentinários/efeitos adversos , Microrradiografia , Cimentos de Resina/efeitos adversos , Propriedades de Superfície
20.
J Appl Oral Sci ; 26: e20170304, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29489933

RESUMO

Titanium tetrafluoride (TiF4) is known for interacting with enamel reducing demineralization. However, no information is available about its potential antimicrobial effect. OBJECTIVES: This study evaluated the antimicrobial and anti-caries potential of TiF4 varnish compared to NaF varnish, chlorhexidine gel (positive control), placebo varnish and untreated (negative controls) using a dental microcosm biofilm model. MATERIAL AND METHODS: A microcosm biofilm was produced on bovine enamel previously treated with the varnishes, using inoculum from human saliva mixed with McBain saliva, under 0.2% sucrose exposure, for 14 days. All experiments were performed in biological triplicate (n=4/group in each experiment). Factors evaluated were: bacterial viability (% dead and live bacteria); CFU counting (log10 CFU/mL); and enamel demineralization (transverse microradiography - TMR). Data were analysed using ANOVA/Tukey's test or Kruskal-Wallis/Dunn's test (p<0.05). RESULTS: Only chlorhexidine significantly increased the number of dead bacteria (68.8±13.1% dead bacteria) compared to untreated control (48.9±16.1% dead bacteria). No treatment reduced the CFU counting (total microorganism and total streptococci) compared to the negative controls. Only TiF4 was able to reduce enamel demineralization (ΔZ 1110.7±803.2 vol% µm) compared to both negative controls (untreated: ΔZ 4455.3±1176.4 vol% µm). CONCLUSIONS: TiF4 varnish has no relevant antimicrobial effect. Nevertheless, TiF4 varnish was effective in reducing enamel demineralization under this model.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Cariostáticos/farmacologia , Esmalte Dentário/microbiologia , Fluoretos/farmacologia , Streptococcus/efeitos dos fármacos , Titânio/farmacologia , Análise de Variância , Animais , Bovinos , Clorexidina/farmacologia , Contagem de Colônia Microbiana , Cárie Dentária/prevenção & controle , Esmalte Dentário/efeitos dos fármacos , Humanos , Viabilidade Microbiana/efeitos dos fármacos , Microrradiografia , Efeito Placebo , Distribuição Aleatória , Reprodutibilidade dos Testes , Saliva/microbiologia , Fluoreto de Sódio/farmacologia , Estatísticas não Paramétricas , Streptococcus/crescimento & desenvolvimento
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