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1.
Braz Oral Res ; 35: e030, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729275

RESUMO

The present study evaluated the ability of Bifidobacterium and Lactobacillus species associated with streptococci to increase insoluble extracellular polysaccharide (EPS) production and initial caries lesion progression. Bovine enamel blocks (n = 190; 4 mm x 4 mm) were prepared, selected according to initial surface hardness (SH), and divided into two groups: a) double combinations: S. mutans with Bifidobacterium or Lactobacillus, and b) triple combinations: S. mutans and S. sobrinus with Bifidobacterium or Lactobacillus species. The blocks were exposed to the bacterial associations for 7 days. Subsequently, quantity of EPS from biofilms and caries lesion depth were determined by means of colorimetric and cross-sectional enamel hardness (ΔKHN) analysis. The data were submitted to one-way analysis of variance, followed by the Bonferroni test (p < 0.05). S. mutans with B. animalis or B. dentium produced a higher quantity of EPS; S. mutans + B. animalis led to the highest ∆KHN. S. mutans + S. sobrinus + B. longum induced greater EPS and ∆KHN values. In conclusion, associations of B. animalis and B. longum with streptococci promoted EPS production and caries lesion progression.


Assuntos
Cárie Dentária , Desmineralização do Dente , Animais , Biofilmes , Bovinos , Estudos Transversais , Esmalte Dentário , Streptococcus mutans
2.
Pediatr Dent ; 43(1): 1E-12E, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33662253

RESUMO

Purpose: To systematically evaluate the horizontal transmission of Streptococcus mutans in children and analyze its relationship with dental caries. Methods: Seven databases were searched for observational studies that have determined the transmission of S. mutans among children younger than seven years. Selection of included studies, data extraction, and quality assessment using Downs and Black's (1998) scoring system were performed. The inverse variance random-effect approach was used to pool the results, and statistical heterogeneity was evaluated using I-squared statistics. Results: Fifteen studies were included for qualitative synthesis, five of which were pooled for quantitative analysis. The risk ratio (RR) of sharing only one genotype in caries-free children versus children with caries was found to be 0.60 (95 percent confidence interval [95% CI] equals 0.45 to 0.80; P ≤ 0.001). The RR of sharing more than one genotype was 1.46 (95% CI equals 1.13 to 1.89; P=0.004) in children with caries versus caries-free children. These findings imply that children sharing only one genotype have a 40 percent lesser risk, and children sharing more than one genotype have a 46 percent higher risk of having dental caries. Conclusions: The systematic review provides evidence of the horizontal transmission of S. mutans and its association with dental caries.


Assuntos
Cárie Dentária , Streptococcus mutans , Criança , Cárie Dentária/epidemiologia , Genótipo , Humanos , Streptococcus mutans/genética
3.
J Infect Public Health ; 14(3): 324-330, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33618277

RESUMO

BACKGROUND: Streptococcus mutans are an oral pathogen that causes dental caries, endocarditis, and systemic dysfunctions, an alternative antibacterial solution from silver nanoparticles (AgNPs) are investigated. METHODS: AgNPs were synthesized using the ethnobotanical product gum Arabic. It influenced the nanoparticles with medicinal value through their role as capping, stabilizing, or surface-attached components. The biophysical characteristics of the synthesized AgNPs were studied using UV-vis spectrum, XRD, EDAX, SEM, and TEM tools. The AgNPs were spherical with the average size less than 10 nm. By using the well diffusion and microdilution techniques, the impact of synthesized AgNPs was tested against S. mutans isolates. RESULTS: The smaller the size, the greater the antibacterial and antiviral potential the particles exhibit. The biophysical characteristics of AgNPs the presence of phenols, alcohols, amides, sulfoxide, flavanoids, terpenoids and steroids. The AgNPs exhibited a good antibacterial action against the oral pathogen S. mutans. The synthesized NPs at a dose level of 200 µg/mL exhibited an inhibition zone with 18.30 ± 0.5 nm diameter. The synthesised nanoparticles inhibited the genes responsible for biofilm formation of S. mutans over host tooth and gums (gtfB, gtfc, gtfD) and virulent protective factors (comDE, brpA and smu 360) and survival promoter genes (gyrA and spaP, gbpB). CONCLUSION: The potent antibiotic action over S. mutans seen with the synthesized NPs, paves the way for the development of novel dental care products. Also, the small-sized NPs promote its applicability in COVID-19 pandemic containment.


Assuntos
Antibacterianos/farmacologia , Cárie Dentária/tratamento farmacológico , Endocardite/tratamento farmacológico , Nanopartículas Metálicas , Prata/farmacologia , Streptococcus mutans/efeitos dos fármacos , Biofilmes , Goma Arábica , Humanos
4.
Arch Oral Biol ; 122: 105022, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33418434

RESUMO

The objective of this study was to perform a comprehensive review of the use of antimicrobial peptides for the prevention and treatment of dental caries. The study included publications in the English language that addressed the use of antimicrobial peptides in the prevention and treatment of caries. These publications were also searchable on PubMed, Web of Science, Embase, Scopus, the Collection of Anti-Microbial Peptides and the Antimicrobial Peptide Database. A total of 3,436 publications were identified, and 67 publications were included. Eight publications reported seven natural human antimicrobial peptides as bactericidal to Streptococcus mutans. Fifty-nine publications reported 43 synthetic antimicrobial peptides developed to mimic natural antimicrobial peptides, fusing peptides with functional sequences and implementing new designs. The 43 synthetic antimicrobial peptides were effective against Streptococcus mutans, and nine peptides specifically targeted Streptococcus mutans. Ten antimicrobial peptides had an affinity for hydroxyapatite to prevent bacterial adhesion. Six antimicrobial peptides were also antifungal. Four antimicrobial peptides promoted remineralisation or prevented the demineralisation of teeth by binding calcium to hydroxyapatite. In conclusion, this study identified 67 works in the literature that reported seven natural and 43 synthetic antimicrobial peptides for the prevention and treatment of caries. Most of the antimicrobial peptides were bactericidal, and some prevented bacterial adhesion. A few antimicrobial peptides displayed remineralising properties with hydroxyapatite.


Assuntos
Antibacterianos/uso terapêutico , Cárie Dentária , Proteínas Citotóxicas Formadoras de Poros/uso terapêutico , Aderência Bacteriana/efeitos dos fármacos , Biofilmes , Cárie Dentária/tratamento farmacológico , Cárie Dentária/prevenção & controle , Durapatita , Humanos , Streptococcus mutans/efeitos dos fármacos , Remineralização Dentária
5.
Arch Oral Biol ; 122: 105032, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33418435

RESUMO

OBJECTIVES: This study aims to investigate the effects of tea extracts on biofilm formation by oral streptococci and the potential mechanisms behind the effects. DESIGN: We examined the effects of five types of tea extracts (green, oolong, black, pu-erh and chrysanthemum tea) on cell surface hydrophobicity and auto-aggregation of three different streptococcal species (Streptococcus mutans, Streptococcus salivarius and Streptococcus mitis) and evaluated their biofilm formation on four disparate hard surfaces (glass, stainless steel, hydroxyapatite and titanium). The correlation between biofilm formation and the cellular properties were investigated in order to study the mechanisms by which the tea extracts affect biofilm formation. RESULTS: Results show that the tea extracts reduced cell surface hydrophobicity (by up to 57.9 %) and, in some cases, altered cellular auto-aggregation (by up to 12 %) and biofilm formation (by up to 2.61 log CFU cm-2). Specifically, oolong tea extract was found to enhance biofilm formation by increasing cellular auto-aggregation and pu-erh tea extract retarded biofilm formation by increasing auto-aggregation. Biofilm formation correlated well to cell surface hydrophobicity and auto-aggregation in combination, but not to either one alone as determined by multiple linear regression analysis. CONCLUSIONS: Tea extracts have the ability to modulate streptococcal biofilm formation by altering cell surface hydrophobicity and cellular aggregation.


Assuntos
Biofilmes/efeitos dos fármacos , Extratos Vegetais/farmacologia , Streptococcus mutans/efeitos dos fármacos , Chá/química , Durapatita , Vidro , Interações Hidrofóbicas e Hidrofílicas , Aço Inoxidável , Titânio
6.
Int J Mol Sci ; 22(1)2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33401545

RESUMO

Poly(methyl methacralyate) (PMMA) has long been used in dentistry as a base polymer for dentures, and it is recently being used for the 3D printing of dental materials. Despite its many advantages, its susceptibility to microbial colonization remains to be overcome. In this study, the interface between 3D-printed PMMA specimens and oral salivary biofilm was studied following the addition of zwitterionic materials, 2-methacryloyloxyethyl phosphorylcholine (MPC) or sulfobetaine methacrylate (SB). A significant reduction in bacterial and biofilm adhesions was observed following the addition of MPC or SB, owing to their protein-repellent properties, and there were no significant differences between the two test materials. Although the mechanical properties of the tested materials were degraded, the statistical value of the reduction was minimal and all the properties fulfilled the requirements set by the International Standard, ISO 20795-2. Additionally, both the test materials maintained their resistance to biofilm when subjected to hydrothermal fatigue, with no further deterioration of the mechanical properties. Thus, novel 3D-printable PMMA incorporated with MPC or SB shows durable oral salivary biofilm resistance with maintenance of the physical and mechanical properties.


Assuntos
Materiais Biocompatíveis/farmacologia , Biofilmes/efeitos dos fármacos , Resinas Compostas/química , Materiais Dentários/farmacologia , Boca/efeitos dos fármacos , Polímeros/química , Impressão Tridimensional/instrumentação , Aderência Bacteriana , Biofilmes/crescimento & desenvolvimento , Humanos , Teste de Materiais , Metacrilatos/química , Boca/microbiologia , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/metabolismo
7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(1): 76-81, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33474893

RESUMO

Objective: To explore the differences in transcriptional levels between mutant strains of csn2 gene of CRISPR-Cas9 system of Streptococcus mutans( S. mutans) and wild-type strains. Methods: The S. mutans UA159, csn2-gene-deleted strains (Δ csn2) and csn2-gene-covering strains (Δ csn2/pDL278- csn2) of S. mutans were cultivated. Total RNA was extracted, and high-throughput sequencing technology was used for transcriptome sequencing. Based on the GO analysis and the KEGG analysis of the differentially expressed genes, the biological processes involved were thoroughly examined. The qRT-PCR method was used to verify the transcriptome sequencing results. Results: The transcriptome results showed that, compared with UA159, there were 176 genes in Δ csn2 whose gene expression changed more than one fold ( P<0.05), of which 72 were up-regulated and 104 were down-regulated. The GO enrichment analysis and the KEGG enrichment analysis revealed that both the up-regulated and down-regulated differentially expressed genes (DEG) were involved in amino acid transport and metabolism. In addition, the biological processes that up-regulated DEGs participated in were mainly related to carbohydrate metabolism, energy production and conversion, and transcription; down-regulated DEGs were mainly related to lipid metabolism, DNA replication, recombination and repair, signal transduction mechanisms, nucleotide transport and metabolism. The functions of some DEGs were still unclear. Results of qRT-PCR verified that the expressions of leuA, leuC and leuD(genes related to the formation of branched-chain amino acids) were significantly down-regulated in Δ csn2 when compared with UA159 and Δ csn2/pDL278- csn2. Conclusion: Through transcriptome sequencing and qRT-PCR verification, it was found that the expression of genes related to branched-chain amino acid synthesis and cell membrane permeability in Δ csn2 changed significantly.


Assuntos
Streptococcus mutans , Transcriptoma , Sistemas CRISPR-Cas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Perfilação da Expressão Gênica , Streptococcus mutans/genética
8.
Monogr Oral Sci ; 29: 19-29, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33427214

RESUMO

The pH value of a biofilm influences the pathogenesis and therapy of oral diseases such as caries and periodontitis. This study aimed to investigate the influence of different initial pH values on the microbial composition, bacterial counts, metabolic activity, and quantity of three defined biofilms representing oral health, caries, and periodontal disease. Respective bacterial suspensions in the nutrient broth were initially adjusted to pH values between 5 and 8. Then biofilms were cultured on polystyrene surfaces coated with a proteinaceous solution for 2 h ("healthy" biofilm), 6 h ("healthy," and "cariogenic" biofilms), 24 h ("cariogenic," and "periodontitis" biofilms), and 48 h ("periodontitis" biofilm). In all biofilms, total bacterial counts were lower at an initial pH of 5 or 5.5 than at higher pH values. In the biofilm representing caries, the percentage of cariogenic bacteria (Streptococcus mutans, S. sobrinus, Lactobacillus acidophilus) was higher at a low pH, the metabolic activity was highest at pH 6-6.5, and biofilm mass was greatest at pH 7-7.5. In the biofilm representing periodontitis, the percentage of Porphyromonas gingivalis increased with the pH. Also, the metabolic activity was highest at pH 8, whereas mass had the highest value at pH 7. In conclusion, the initial pH value influences biofilm formation. In particular, metabolic activity and the amount of bacteria associated with disease correlated with the respective pH known to be of importance in the development of caries (relatively low pH) and periodontitis (higher pH). Modifying the pH level in oral biofilms might be an alternative concept in (primary) prevention and treatment, not only of caries but also of periodontitis.


Assuntos
Cárie Dentária , Streptococcus mutans , Biofilmes , Humanos , Concentração de Íons de Hidrogênio , Lactobacillus acidophilus
9.
Monogr Oral Sci ; 29: 201-213, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33427218

RESUMO

Dental biofilms can cause major oral diseases like gingivitis, periodontitis, and caries. Orthodontic appliances promote supra- and subgingival biofilm accumulation, alter the oral microbiome, and hamper oral hygiene. Orthodontic treatment can be associated with adverse effects, such as enamel decalcification, gingivitis, and periodontal disease. The aim of this review is to summarize the changes in supra- and subgingival biofilm and periodontal tissues during and after orthodontic treatment. Studies have reported elevated levels of Streptococcus mutans and periodontopathogenic bacteria in patients undergoing orthodontic treatment. In general, the microbial changes and periodontal parameters decreased to pretreatment levels after appliance removal. Nevertheless, some adverse effects associated with orthodontic treatment are not reversible, such as enamel decalcifications caused by metabolic products of high levels of cariogenic bacteria. The evidence suggests that the roughness and constituents of the orthodontic materials influence the bacterial colonization. Therefore, several antibacterial orthodontic bonding systems, which show antibacterial effects in vitro, have been developed. The importance of adequate oral hygiene should be emphasized to all orthodontic patients. They should be frequently reminded and motivated to obtain a good oral hygiene. The evidence from the current literature suggests the safest way for orthodontic treatment in periodontally diseased patients may be after successful completion of the periodontal therapy. However, the exact time point needs to be better clarified in future studies.


Assuntos
Cárie Dentária , Gengivite , Biofilmes , Cárie Dentária/terapia , Humanos , Aparelhos Ortodônticos/efeitos adversos , Streptococcus mutans
10.
Monogr Oral Sci ; 29: 80-90, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33427222

RESUMO

Untreated dental caries is the most prevalent disease worldwide. Development of caries is associated with the intake of sugar. The microorganisms utilize the sugar and create an acidic environment, which results in mineral loss. The appropriate use of fluoride is associated with a decline of caries. Another approach in preventing caries might be the increase of pH in dental plaque. During recent years, arginine has increasingly become the focus of interest. This is based on the fact that certain streptococci possess an arginine deiminase system (ADS) which metabolizes free arginine. In vivo, the incidence of caries was inversely correlated with ADS activity in saliva and dental plaque. ADS is highly active in Streptococcus gordonii and S. sanguinis, but is absent in S. sobrinus and S. mutans. In the presence of 1.5% L-arginine, S. gordonii and S. sanguinis, but not S. mutans and S. sobrinus, synthesize the metabolite citrulline and increase the pH of the environment.In defined multispecies biofilms consisting of ADS-positive and ADS-negative streptococci, supplementation with 1.5% arginine suppressed the growth of ADS-negative by favoring ADS-positive streptococci together with an increase in the pH of the environment. Evaluating the influence of daily manual removal of the biofilm in vitro by brushing with a commercial toothpaste containing fluoride and arginine resulted in less surface microhardness even when compared with a toothpaste with fluoride only. Recent studies clinically investigated the effect of using an arginine-containing dentifrice and reported a decrease of DMFS by about 10-20%.


Assuntos
Cárie Dentária , Arginina , Biofilmes , Cárie Dentária/prevenção & controle , Humanos , Streptococcus mutans , Streptococcus sanguis
11.
Monogr Oral Sci ; 29: 1-11, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33427230

RESUMO

In reality, most microorganisms are not free floating. They exist in biofilms, a community of many of them from the same species or from other genera and attached to surfaces.Microorganisms undergo a transition from free-floating, planktonic microorganisms to a sessile, surface-attached one. Contact with a surface induces changes in gene expression, and a strong attachment of microcolonies occurs only after a few hours. The maturation of a biofilm is associated with matrix formation. The matrix is of importance as it provides stability and protects against environmental insults, it consists of polysaccharides, water, lipids, proteins, and extracellular DNA. Biofilms can be found everywhere - in the environment, in water systems - and they play an important role in medicine and dentistry. In medicine, infections of chronic wounds, of the respiratory tract in cystic fibrosis infections, or when linked with incorporated biomaterial are mostly biofilm associated. In the oral cavity, the most prevalent oral diseases, dental caries, and periodontitis are multi-species biofilm-associated diseases. Although not acting alone, key pathogens drive the development of the microbial shift. Microorganisms metabolize sugar and create an acidic environment where aciduric bacteria (including mutans streptococci) become dominant, which leads to the demineralization of enamel and dentine. Porphyromonas gingivaliscauses biofilm dysbiosis in the development of periodontal disease. Biofilm-associated infections are extremely difficult to treat. The matrix serves as a barrier to antimicrobial agents and there are subpopulations of dormant bacteria resistant to antimicrobials requiring metabolically active cells. Approaches to treat biofilm-associated infections include the modification of the biofilm composition, inhibitors of quorum-sensing molecules, or interfering with matrix constituents.


Assuntos
Cárie Dentária , Biofilmes , Humanos , Boca , Percepção de Quorum , Streptococcus mutans
12.
Monogr Oral Sci ; 29: 38-52, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33427232

RESUMO

When analyzing the activity of antimicrobial agents, it should be considered that microorganisms mainly occur in biofilms. Data obtained for planktonic bacteria cannot be transferred non-critically to biofilms. Biofilm models should consider both the relevant microorganisms and the conditions present in the environment. The selection of the model depends on the question to be answered. In dentistry, single species, multispecies, or microcosms originating from saliva or dental biofilm are used to culture biofilms. Microorganism selection depends on the focus of the study, for example caries biofilms mostly include Streptococcus mutans, an endodontic biofilm consists mostly of Enterococcus faecalis, and defined anaerobes are used in periodontal/peri-implant biofilms. In contrast to single-species biofilm models in medicine, where the lowest concentration of the antimicrobial that kills microorganisms is measured, the common analyzed variables are counts of colony-forming units or the percentage of dead bacteria determined by confocal laser scanning microscopy after applying a differentiating stain. All the models are helpful to evaluate new antimicrobial treatment options. Conclusions regarding the antimicrobial activity tendency of the therapeutics can be drawn. However, there are limitations of the model and ultimately a new therapy has to be proven in randomized controlled clinical trials.


Assuntos
Biofilmes , Cárie Dentária , Enterococcus faecalis , Humanos , Saliva , Streptococcus mutans
13.
Braz. dent. sci ; 24(1): 1-7, 2021. tab, ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1145548

RESUMO

Though aloe vera extract, green tea extract and coriander oil are proven antimicrobial agents, very little information is available regarding its effects on oral bacteria, Streptococcus mutans, which is responsible for initiating caries and Enterococcus faecalis, responsible for failure of root canal treatment. Objective: To find the antimicrobial activity of aloe vera extract, black tea extract and coriander oil against S. mutans and E. faecalis. Materials and Methods: The agar well diffusion method was used to determine the antibacterial activity of Aloe vera extract, black tea extract and coriander oil. Different concentration of prepared plant extracts and coriander seed oil (50 & 100 µl) was incorporated into the wells and the plates containing S. mutans and E. faecalis were incubated at 37 °C for 24 h. The antibiotic (amoxicillin 30 µl) was used as positive control. Zone Of Inhibition (ZOI) was recorded in each plate. Results: For S. mutans, the maximum ZOI was created by coriander oil with a diameter of 25.00±0.58 mm at 50 µl and for E. faecalis, maximum ZOI was created by aloe vera extract 16.00±0.58 mm at 100 µl concentration which were far better than the control: amoxicillin 30 µl concentration. Conclusion: The extracts of Aloe vera, black tea and coriander oil, showed significant activity against the investigated microbial strains, Streptococcus mutans and Enterococcus faecalis which further helps in the development of new topical agents that help in reducing the numbers of these organisms present in the oral cavity. (AU)


Embora o extrato de aloe vera, extrato de chá verde e óleo de coentro sejam agentes antimicrobianos comprovados, há pouca informação disponível sobre seus efeitos nas bactérias orais, Streptococcus mutans, que é responsável por iniciar cáries e Enterococcus faecalis, responsável pela falha do tratamento de canal radicular. Objetivo: Avaliar a atividade antimicrobiana do extrato de aloe vera, extrato de chá preto e óleo de coentro contra S. mutans e E. faecalis. Materiais e Métodos: O método de difusão em agar foi usado para determinar a atividade antibacteriana do extrato de Aloe vera, extrato de chá preto e óleo de coentro. Diferentes concentrações dos extratos de plantas e óleo de semente de coentro (50 e 100 µl) foram preparados e colocados nos poços e nas placas contendo S. mutans e E. faecalis e foram incubadas a 37°C por 24 h. O antibiótico (amoxicilina 30 µl) foi utilizado como controle positivo. A zona de inibição (ZOI) foi registrada em cada placa. Resultados: Para S. mutans, a ZOI máxima foi obtida com o óleo de coentro com um diâmetro de 25,00 ± 0,58 mm a 50 µl e para E. faecalis, a ZOI máxima foi obtiada pelo extrato de aloe vera 16,00 ± 0,58 mm na concentração de 100 µl, as quais foram melhores do que o controle: concentração de 30 µl de amoxicilina. Conclusão: Os extratos de Aloe vera, chá preto e óleo de coentro apresentaram atividade significativa contra as cepas microbianas investigadas, Streptococcus mutans e Enterococcus faecalis auxiliando no desenvolvimento de novos agentes tópicos visando a redução do número desses organismos presentes no cavidade oral. (AU)


Assuntos
Streptococcus mutans , Chá , Enterococcus faecalis , Aloe , Microbiota
14.
Int J Dent Hyg ; 19(2): 193-200, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33369141

RESUMO

OBJECTIVE: This study aimed to find the relation of the MS co-existence with the decayed, missing (Extracted) and filled teeth (DMFT) score and the prevalence of Streptococcus mutans serotypes in the Iranian population. METHODS: In this cross-sectional research conducted in 2018, volunteers aged 10-60< years were measured by population selection criteria. PCR technique was used to screen MS serotypes in the homogenized saliva and plaque samples. RESULTS: 499 subjects met the selection criteria of the study population. Out of 499 samples, 448 samples were finalized for serotype determination and DMFT relation evaluation. From 448, 348 (77.6%) samples harboured only S. mutans, 44 (9.8%) had both S. mutans and S. sobrinus, 6 (1.3%) were positive for S. sobrinus alone, and 94 (20.9%) were free of both specious. The mean DMFT score in people with S. mutans (6.7) was higher than S. mutans negative (4.6) participants (p < 0.05). In people with both S. mutans and S. sobrinus, the mean DMFT did not change significantly. The frequency of c, e, f and k serotypes was 47.7, 22.7, 27.5 and 22.1%, respectively. The mean DMFT score in participants with serotype e was significantly higher than others (p < .05). CONCLUSIONS: People can acquire different S. mutans serotypes over a lifetime. The high prevalence rate of serotype k, a systemic S. mutans serotype, calls worldwide studies on the prevalence of serotype k strains.


Assuntos
Cárie Dentária , Streptococcus sobrinus , Adolescente , Adulto , Criança , Estudos Transversais , Cárie Dentária/epidemiologia , Humanos , Irã (Geográfico)/epidemiologia , Pessoa de Meia-Idade , Prevalência , Saliva , Sorogrupo , Streptococcus mutans , Adulto Jovem
15.
Mol Oral Microbiol ; 36(1): 67-79, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33316854

RESUMO

Ligustrum robustum (Roxb.) Blume is utilized as a traditional Chinese herbal tea with various health benefits and protective effects. Streptococcus mutans is an important cariogenic oral bacteria species. The present study aimed to assess the influence of Ligustrum robustum extract (LRE) on the biofilm formation of S. mutans and the mechanism of its action, as well as to identify its chemical components. For chemical identification, HPLC-MS and nuclear magnetic resonance were applied and four identified phytochemicals were reported (Ligurobustoside B, Ligurobustoside N, Ligurobustoside J, and Ligurobustoside C). The dose-dependent (0.5 to 2.0 µg/µL) antimicrobial toxicity of LRE against S. mutans biofilm formation and exopolysaccharide (EPS) synthesis was evaluated by confocal laser scanning microscopy (CLSM), Crystal violet stain, and CFU counting. The microstructure of S. mutans biofilm treated with LRE was investigated both on glass coverslips and ex vivo bovine dental enamel by scanning electron microscopy (SEM). Moreover, LRE downregulated the expression of S. mutans glucosyltransferase-encoding genes gtfB, gtfC, and gtfD, and the quorum sensing (QS) factors comD and comE, suggesting its toxic mechanism. In addition, the result of CCK-8 test on human oral cells revealed an acceptable biocompatibility of LRE. These findings indicated the possible application of this daily consumed herbal tea for caries prevention.


Assuntos
Cárie Dentária , Ligustrum , Animais , Biofilmes , Bovinos , Cárie Dentária/prevenção & controle , Humanos , Extratos Vegetais/farmacologia , Streptococcus mutans
16.
Arch Oral Biol ; 122: 105024, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33352361

RESUMO

OBJECTIVE: We evaluated the effect of antimicrobial photodynamic therapy (a-PDT) with Rose Bengal and blue light LED on bacteria that initiate and promote dental caries. DESIGN: Colony forming units of Streptococcus mutans, Streptococcus sobrinus, Streptococcus sanguinis, and Lactobacillus salivarius under planktonic and biofilm conditions were counted after a-PDT treatment using Rose Bengal and blue light LED. In addition, cariogenic bacteria from saliva and dental plaques from ten volunteers were used for evaluation of a-PDT treatment. RESULTS: We found that a-PDT using Rose Bengal at > 10 µg/mL had antimicrobial effects on oral Gram-positive S. mutans, S. sobrinus, S. sanguinis, and L. salivarius under both planktonic and biofilm conditions. The effect was also observed for cariogenic bacteria that formed biofilms containing water-insoluble glucans, through which the bacteria are firmly attached to the tooth surface. Moreover, a-PDT led to a marked reduction in cariogenic bacteria in saliva and dental plaques. CONCLUSION: a-PDT could be a useful approach for controlling dental caries in dental surgery.


Assuntos
Anti-Infecciosos , Fotoquimioterapia , Rosa Bengala/farmacologia , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/efeitos da radiação , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/efeitos da radiação , Cárie Dentária/tratamento farmacológico , Humanos
17.
Artigo em Inglês | MEDLINE | ID: mdl-33374694

RESUMO

The scientific community has definitely demonstrated the importance of the use of mouthwash in daily oral hygiene. In our pilot study, we tested the effectiveness of a novel mouth rinse containing sea salt, xylitol, and lysozyme. Streptococcus mutans (S. mutans) growth, and plaque index in adolescent patients aged 14-17 years, were observed. The bacterial load was investigated by in vitro microbiological analysis; the plaque index was assessed through the O'Leary's Plaque Control Record (PCR). The study has shown that the use of a sea salt-based mouthwash in daily oral hygiene reduces the bacterial levels of S. mutans (p < 0.01) linked to the combined action of xylitol and lysozyme, together with the action of sea salt. Our preliminary data confirm and improve the main results reported in the scientific literature on the importance of the use of xylitol, lysozyme, and sea salt in oral health.


Assuntos
Antissépticos Bucais/uso terapêutico , Higiene Bucal , Cloreto de Sódio/uso terapêutico , Xilitol/uso terapêutico , Adolescente , Placa Dentária/prevenção & controle , Humanos , Muramidase/uso terapêutico , Projetos Piloto , Streptococcus mutans
18.
Int J Mol Sci ; 21(24)2020 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-33322170

RESUMO

Streptococcus mutans (S. mutans) is widely regarded as the main cause of human dental caries via three main virulence factors: adhesion, acidogenicity, and aciduricity. Citric acid is one of the antibiotic agents that can inhibit the virulence capabilities of S. mutans. A full understanding of the acidic resistance mechanisms (ARMs) causing bacteria to thrive in citrate transport is still elusive. We propose atomic force microscopy (AFM) equipped with a fluid cell to study the S. mutans ARMs via surface nanomechanical properties at citric acid pH 3.3, 2.3, and 1.8. Among these treatments, at pH 1.8, the effect of the citric acid shock in cells is demonstrated through a significantly low number of high adhesion zones, and a noticeable reduction in adhesion forces. Consequently, this study paves the way to understand that S. mutans ARMs are associated with the variation of the number of adhesion zones on the cell surface, which is influenced by citrate and proton transport. The results are expected to be useful in developing antibiotics or drugs involving citric acid for dental plaque treatment.


Assuntos
Biofilmes/efeitos dos fármacos , Ácido Cítrico/farmacologia , Microscopia de Força Atômica/instrumentação , Microscopia de Força Atômica/métodos , Streptococcus mutans/efeitos dos fármacos , Virulência/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Adesão Celular/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Impressão Tridimensional , Propriedades de Superfície , Fatores de Virulência
19.
Biofouling ; 36(10): 1182-1195, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33334195

RESUMO

The effect of xylitol tablets with (XPT) and without (XT) red propolis on salivary parameters, dental biofilm and acceptability of adolescents was evaluated through a blinded randomized crossover clinical trial. Healthy volunteers were allocated in the XPT and XT groups with a 30-day washout period for consumption of two tablets/dayfor seven days. An increase in salivary parameters was only observed immediately after tablet consumption, without differences between XPT and XT. The results for total microorganisms were similar, but XT was better in controlling Streptococcus spp. Rothia dentocariosa and Streptococcus salivarius were the most frequent in the biofilm and saliva, respectively. XPT and XT showed similar acceptability, with the highest purchase intention for XT. Although propolis did not enhance the properties of XT, further studies testing different protocols and follow-up are necessary; XT controlled Streptococcus spp. in biofilms, which demonstrate its potential for clinical application.


Assuntos
Biofilmes , Própole , Adolescente , Humanos , Micrococcaceae , Saliva , Streptococcus mutans , Comprimidos , Xilitol
20.
Biofouling ; 36(10): 1196-1209, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33349045

RESUMO

Biofilms were developed from human saliva on bovine enamel discs in four experimental conditions to investigate dental caries development: feast and famine (M1), abundance and scarcity (M2), three meals daily (M3), and three meals plus two snacks daily (M4). The main difference between these models was the diet for microbial growth. The evaluations included verifying the pH of the spent culture media and analyzing the enamel discs for demineralization (microhardness and roughness) and biofilms (biomass, viable populations of mutans streptococci, and total microbiota). Two major behaviors were observed: M1 and M2 promoted an acidic environment, while M3 and M4 maintained pH values closer to neutral. The demineralization process was slower in the neutral groups but more pronounced in M3, while a greater increase in microbiota and biomass was observed over time for both neutral groups. Thus, the M3 model was better at mimicking the oral environment that leads to demineralization.


Assuntos
Biofilmes , Dieta Cariogênica , Animais , Bovinos , Cárie Dentária/etiologia , Humanos , Concentração de Íons de Hidrogênio , Streptococcus mutans , Desmineralização do Dente/etiologia
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