The Clinical Pattern and Prevalence of Streptococcus mutans and Streptococcus sobrinus among Adult and Children Patients with Dental Caries

Abstract Objective: To explore the clinical pattern, host factors, and presentation of Streptococcus mutans related to caries incidence among children and adults visiting Universitas Airlangga dental clinic. Material and Methods: This was an observational study with a cross-sectional approach with 50 patients in each group of carious children (6-12 years) and adults (18-35 years). Dental decay samples were taken by sterile excavator, put in a BHI's transport medium, and directly incubated overnight at 37 ºC. The next day, they were sub-cultured microbiologically in Tryptone Yeast Cystine Sucrose Bacitracin (TYCSB) selective medium. Bacterial species and serogroups were examined by PCR. All patient's data were collected from medical records and direct observation. Results: Caries were mostly media type in both children and adults. Oral hygiene (OHIS) in children was higher than in adults but not significantly different according to their DMFT. The highest scores for decay, missed and filled teeth were 16, 8 and 7, with an average of 6.82, 1.22 and 0.63, considered quite high. Conclusion: The prevalence of S. mutans was higher in children's caries than in adults, but among the adult patients the co-incidence of S. mutans and S. sobrinus was associated with higher DMFT. The mutans serotypes e, f, and d were more prevalent among children than adults.

Type-2 Diabetes Mellitus Individuals Carry Different Periodontal Bacteria

ABSTRACT Objective: To identify etiologic microbiota associated periodontal diseases among diabetes patients and the factors related to the most commonly identified bacteria species. Material and Methods: Periodontal plaque samples from 11 diabetic participants and 13 non-diabetic controls were collected to assess their aerobic and anaerobic bacterial growth. Different distinct colonies were identified by microscopic and 16srDNA sequencing. Pearson's chi-square tests were conducted to examine any association between categorical variables. Results: The diabetic subjects revealed a more intense plaque formation with a mean plaque index of 2.4 compared to 1.8 in non-diabetics. A total of 86 bacteria were isolated from 24 plaque samples, 44 were aerobic, and 42 were anaerobic. Only aerobic isolates, 22 from diabetic patients and 22 from non-diabetic patients, were evaluated in these analyses. Bacillus spp. (B. cereus mainly) and Klebsiella spp. (K. pneumoniae, K. aerogenes, K. oxytoca) were detected markedly higher in non-diabetic individuals than in diabetic subjects (p=0.026 and p=0.021, respectively). Some bacteria were only identified in the dental plaque of diabetic individuals, namely, Bacillus mojavensis, Enterobacter cloacae, Proteus mirabilis, Staphylococcus epidermidis, Staphylococcus hominis, Staphylococcus pasteuri, Streptococcus mutans, and Streptococcus pasteurianus. The presence of acid reflux and jaundice were significantly associated with the most common bacterial isolate, namely Bacillus spp., with the p-values of 0.007 and 0.001, respectively. Conclusion: Type-2 diabetes mellitus is associated with a higher amount of dental plaques. Periodontal plaque samples from diabetic and non-diabetic subjects possess differential microbial communities. Diabetic plaques contain more versatile microbes predominated by gram-positive streptococci and staphylococci.

Creating Antibacterial Properties in Flowable Dental Composites by Incorporation of 3, 4-dihydropyrimidin-2(1H)-ones

ABSTRACT Objective: To investigate the antibacterial, mechanical, physical properties and water sorption of flowable dental composites containing 3,4-dihydropyrimidin-2(1H)-ones. Material and Methods: 3,4-dihydropyrimidin-2(1H)-ones was synthesized and the antibacterial activity of flowable dental composites containing 0-5 wt% 3,4-dihydropyrimidin-2(1H)-ones and also of their mechanical and physical properties on flowable dental composites were investigated. Flexural strength was measured by a three-point bending test. Compressive strength (CS), Water sorption (WS) and depth of cure (DOC) were investigated. The data were analyzed by One-way ANOVA test. The level of significance was determined as p<0.01. Results: The direct contact test demonstrates that by increasing the 3,4-dihydropyrimidin-2(1H)-ones content, the bacterial growth is significantly diminished (p<0.001). The average flexural strength results show that with increasing 3,4-dihydropyrimidin-2(1H)-ones until 3% in the composite, no significant difference was observed in flexural strength (p>0.001) and the mean of compressive strength results show no significant difference between 0-4% groups (p>0.001). The mean of water sorption and depth of cure results shows no significant difference between groups (p>0.001). Conclusion: Incorporation of 3,4-dihydropyrimidin-2(1H)-ones into flowable resin composites in 3% wt can reduce the activity of Streptococcus mutans.

Sucrose, Lactose, and Xylitol Exposures Affect Biofilm Formation of Streptococcus mutans

Abstract Objective: To determine the level of biofilm formation of S. mutans after being exposed to 5% sucrose, 8% lactose, or 1% xylitol. Material and Methods: This research was a laboratory-based experimental study with post-test only control group design. S. mutans was grown in test tubes containing tryptose soy broth (TSB) medium supplemented with 1% glucose. They were incubated at 37° C for 24 hours to grow the biofilms. The culture was then exposed to 5% sucrose, 8% lactose or 1% xylitol, incubated for 24 hours at 37° C, and examined using ELISA at a wavelength of 625 nm. The statistical analysis was performed using a one-way analysis of variance followed by the least significant difference test (a=0.05). Results: There were some differences in the biofilm formation of S. mutans after exposure to 5% sucrose, 8% lactose, or 1% xylitol (p<0.05). An LSD test indicated significant differences among the biofilm formations after exposure to 5% sucrose and 8% lactose and between 5% sucrose and 1% xylitol. In comparison, there were no significant differences (p>0.05) between 8% lactose and 1% xylitol. Conclusion: Sucrose, lactose and xylitol can form biofilms and the formation of lactose biofilms is the same as xylitol.

PepO is a target of the two-component systems VicRK and CovR required for systemic virulence of Streptococcus mutans.

Streptococcus mutans, a cariogenic species, is often associated with cardiovascular infections. Systemic virulence of specific S. mutans serotypes has been associated with the expression of the collagen- and laminin-binding protein Cnm, which is transcriptionally regulated by VicRK and CovR. In this study, we characterized a VicRK- and CovR-regulated gene, pepO, coding for a conserved endopeptidase. Transcriptional and protein analyses revealed that pepO is highly expressed in S. mutans strains resistant to complement immunity (blood isolates) compared to oral isolates. Gel mobility assay, transcriptional, and Western blot analyses revealed that pepO is repressed by VicR and induced by CovR. Deletion of pepO in the Cnm+ strain OMZ175 (OMZpepO) or in the Cnm- UA159 (UApepO) led to an increased susceptibility to C3b deposition, and to low binding to complement proteins C1q and C4BP. Additionally, pepO mutants showed diminished ex vivo survival in human blood and impaired capacity to kill G. mellonella larvae. Inactivation of cnm in OMZ175 (OMZcnm) resulted in increased resistance to C3b deposition and unaltered blood survival, although both pepO and cnm mutants displayed attenuated virulence in G. mellonella. Unlike OMZcnm, OMZpepO could invade HCAEC endothelial cells. Supporting these phenotypes, recombinant proteins rPepO and rCnmA showed specific profiles of binding to C1q, C4BP, and to other plasma (plasminogen, fibronectin) and extracellular matrix proteins (type I collagen, laminin). Therefore this study identifies a novel VicRK/CovR-target required for immune evasion and host persistence, pepO, expanding the roles of VicRK and CovR in regulating S. mutans virulence.

In Silico Selection and In Vitro Evaluation of New Molecules That Inhibit the Adhesion of Streptococcus mutants through Antigen I/II.

Streptococcus mutans is the main early colonizing cariogenic bacteria because it recognizes salivary pellicle receptors. The Antigen I/II (Ag I/II) of S. mutans is among the most important adhesins in this process, and is involved in the adhesion to the tooth surface and the bacterial co-aggregation in the early stage of biofilm formation. However, this protein has not been used as a target in a virtual strategy search for inhibitors. Based on the predicted binding affinities, drug-like properties and toxicity, molecules were selected and evaluated for their ability to reduce S. mutans adhesion. A virtual screening of 883,551 molecules was conducted; cytotoxicity analysis on fibroblast cells, S. mutans adhesion studies, scanning electron microscopy analysis for bacterial integrity and molecular dynamics simulation were also performed. We found three molecules ZINC19835187 (ZI-187), ZINC19924939 (ZI-939) and ZINC19924906 (ZI-906) without cytotoxic activity, which inhibited about 90% the adhesion of S. mutans to polystyrene microplates. Molecular dynamic simulation by 300 nanoseconds showed stability of the interaction between ZI-187 and Ag I/II (PDB: 3IPK). This work provides new molecules that targets Ag I/II and have the capacity to inhibit in vitro the S. mutans adhesion on polystyrene microplates.

Associação da quitosana à terapia fotodinâmica para controle de Streptococcus mutans e biofilme microcosmos / Association of Photodynamic Therapy with chitosan for the control of Streptococcus mutans and microfilm biofilm

A terapia fotodinâmica (TFD) é uma técnica que combina um fotossensibilizador (FS) com luz visível e oxigênio molecular, podendo ser utilizada como agente antimicrobiano no controle de diversas doenças infecciosas, como a cárie dentária. A quitosana vem demonstrando atividade promissora quando associada à alguns fotossensibilizadores. Portanto, o objetivo desse trabalho foi investigar a associação da quitosana com o fotossensibilizador Photodithazine® (PDZ) na TFD sobre culturas planctônicas e biofilmes de S. mutans, bem como avaliar sua eficácia sobre biofilmes microcosmos orais. Inicialmente, foi preparada uma suspensão de S. mutans UA 159 padronizada em 106 células/mL. Para o estudo em culturas planctônicas, foi adicionada a suspensão de S. mutans em placas de 96 poços. Para o estudo em biofilmes, foram confeccionadas amostras de esmalte de dentes bovinos como substrato para a formação do biofilme em placas de 24 poços. As culturas planctônicas e os biofilmes foram tratados de acordo com os grupos experimentais, recebendo adição de PDZ, quitosana ou PBS, seguido pela irradiação ou pela manutenção em ambiente escuro (controle). Os efeitos dos tratamentos foram analisados por meio da contagem de UFC/mL de S. mutans em ágar Infusão Cérebro Coração (BHI) incubadas por 48h a 37°C (5% de CO2) e Microscopia Eletrônica de Varredura (MEV). Além disso, para confirmar a penetração do FS e da quitosana nas células de S. mutans foi realizado teste de absorbância. A seguir, foram estudados os efeitos da terapia fotodinâmica com PDZ associado à quitosana sobre biofilmes microcosmos de saliva formados sobre corpos-de-prova de esmalte bovino. Os efeitos da TFD sobre os biofilmes foram analisados por meio da contagem de células viáveis de micro-organismos totais em ágar BHI e estreptococos do grupo mutans em ágar Mitis Salivarius Bacitracina Sacarose (MSBS). Os dados foram analisados por ANOVA e teste de Tukey. Os resultados demonstraram que a TFD mediada por PDZ foi capaz de reduzir a contagem de células viáveis de S. mutans tanto nos testes planctônicos como nos biofilmes, assim como reduzir a contagem de micro-organismos totais e estreptococos do grupo mutans em biofilmes microcosmos orais. Esses efeitos antimicrobianos foram ainda maiores quando à quitosana foi associada à TFD. A redução do número de células viáveis foi confirmada nas imagens de MEV, nas quais pode-se observar a desestruturação das células e matriz do biofilme. Nos testes de absorção, observou-se que a quitosana aumentou a capacidade de penetração do PDZ nas células de S. mutans. Concluiu-se que a quitosana apresentou capacidade de potencializar a atividade antimicrobiana da TFD mediada por PDZ sobre S. mutans e biofilmes microcosmos orais(AU)

Photodynamic therapy (PDT) is a technique that combines a photosensitizer (FS) with visible light and molecular oxygen and can be used as an antimicrobial agent to control various infectious diseases, such as dental caries. Chitosan has shown promising activity when associated with some photosensitizers. Therefore, the objective of this study was to investigate the association of chitosan with the Photodithazine® photosensitizer (PDZ) in PDT on S. mutans planktonic cultures and biofilms, as well as evaluating its effectiveness on oral microcosm biofilms. Initially, a standardized S. mutans UA159 suspension at 106 cells/mL was prepared. For the study in planktonic cultures, the suspension of S. mutans in 96 well plates was added. For biofilm study, bovine tooth enamel samples were made as substrate for biofilm formation in 24 well plates. Planktonic cultures and biofilms were treated according to the experimental groups, receiving the addition of PDZ, chitosan or PBS, followed by laser irradiation or maintenance in a dark environment (control). The effects of treatments were analyzed by counting CFU/mL of S. mutans on Brain Heart Infusion Agar (BHI) incubated for 48h at 37 °C (5% CO2 ) and Scanning Electron Microscopy (SEM). In addition, to confirm the penetration of PS and chitosan in S. mutans UA159 cells, an absorbance test was performed. Next, the effects of photodynamic therapy with PDZ associated with chitosan on saliva microcosm biofilms formed on bovine enamel specimens were studied. The effects of PDT on biofilms were analyzed by counting viable cells of total microorganisms on BHI agar and mutans streptococci on Mitis Salivarius Bacitracin Sucrose (MSBS) agar. The data were analyzed by ANOVA and Tukey's test. The results demonstrated that PDZ-mediated PDT was able to reduce the viable cell count of S. mutans in both planktonic and biofilm tests, as well as to reduce the count of total microorganisms and mutans streptococci in oral microcosm biofilms. These antimicrobial effects were even greater when chitosan was associated with PDT. The reduction in the number of viable cells was confirmed in the SEM images, in which it is possible to observe the breakdown of the cells and the biofilm matrix. In the absorption tests, it was observed that chitosan increased the penetration capacity of PDZ in S. mutans cells. It was concluded that chitosan was able to potentiate PDZ-mediated PDT antimicrobial activity on S. mutans and oral microcosm biofilms(AU)

Sucrose and Xylitol-Induced Streptococcus mutans Biofilm Adherence

Abstract Objective: To study the adherence of Streptococcus mutans biofilm after induction with sucrose and xylitol. Material and Methods: Laboratory experimental study incorporating posttest-only control group design. S. mutans biofilm was generated for 24 hours at a temperature of 37°C using BHIB with 5% sucrose and BHIB with 1% xylitol. An adherence assay was conducted in accordance with the method applied previously. The quantity of adhered bacteria was measured by means of a spectrophotometer at 570 nm. The data were presented as mean and standard deviation. Results: A biofilm induced with sucrose has a higher adherence level (0.9294 ± 0.0431) compared with one induced with xylitol (0.5095 ± 0.0392). Sucrose induces adherence levels by increasing glucan binding protein and glucosyltransferase of the bacteria, whereas xylitol will inhibit the glycolysis process of the bacteria. Conclusion: The adherence of sucrose-induced S. mutans biofilm is higher than that of xylitol-induced S. mutans biofilm.

Atividade antifúngica de metabólitos produzidos por Streptococcus mutans sobre Candida albicans / Antifungal activity of metabolites produced by Streptococcus mutans on Candida albicans

RESUMO A formação de biofilmes e produção de hifas por Candida albicans são importantes fatores de virulência, principalmente, para a aderência à mucosa e invasão tecidual. A busca por metabólitos secundários produzidos por S. mutans é de suma importância, pois poderá fornecer novas estratégias terapêuticas no combate às infecções por Candida, possibilitando o desenvolvimento de medicamentos capazes de inibir os mecanismos de patogenicidade das espécies desse gênero. Desse modo, o objetivo desse estudo foi obter o extrato bruto e frações a partir do sobrenadante da cultura de 4 h de S. mutans (UA159) e avaliar seus efeitos sobre os mecanismos de patogenicidade de C. albicans (ATCC18804) por meio de estudos in vitro. Após o cultivo de S. mutans, o extrato bruto foi obtido via partição líquido-líquido com acetato de etila (3x) e posteriormente fracionado em coluna de sílica derivatizada C-18 eluída com gradiente MeOH:H2O, fornecendo cinco frações (SM-F1, SM-F2, SM-F3, SM-F4 e SM-F5). A identificação das substâncias contidas no extrato bruto e frações foi realizada utilizando cromatografia gasosa acoplada a espectrometria de massas (CGEM), sendo encontradas as seguintes substâncias: ácido octanóico e uridina no extrato bruto, ácido propanóico, (3R)-3-Methyl-1,4-bis(trimethylsilyl)piperazine-2,5- dione, pirimidina, gulose e oleamida na SM-F1 e ácido nicotínico e triptofano na SM- F2. O extrato bruto e as frações foram submetidos aos ensaios de bioatividade sobre a formação de hifas de C. albicans e analisados por microscopia óptica e microscopia eletrônica de varredura (MEV). O extrato bruto e a fração SM-F2, que resultou em maior inibição das hifas, foram investigados na expressão de genes de C. albicans envolvidos no mecanismo de filamentação (CPH1, EFG1, HWP1, UME6 e YWP1) por PCR quantitativo em tempo real (RT-qPCR). Além disso, o potencial de inibição do extrato bruto, frações SM-F1 e SM-F2 foi avaliado sobre a formação de biofilmes de C. albicans, analisados pela quantificação de células viáveis (UFC/mL) e MEV Os resultados demonstraram inibição significativa na formação de hifas de C. albicans pelo extrato bruto e principalmente, pela SM-F2, com alterações significativas na expressão de todos os genes analisados. O extrato bruto e SM-F2 regularam negativamente a expressão dos genes CPH1, EFG1, HWP1 e UME6, em contrapartida, regularam positivamente a expressão do gene YWP1, envolvido no mecanismo de dispersão das leveduras. Nas análises de UFC/mL, os resultados demonstraram redução nas contagens de C. albicans nos biofilmes formados quando em contato com o extrato bruto, frações SM-F1 e SM-F2 em todas as concentrações testadas, sendo que o extrato bruto reduziu totalmente as células de C. albicans na concentração 15 mg/mL. Os resultados do nosso estudo demonstraram que o extrato bruto e frações de S. mutans apresentaram efeitos inibitórios sobre importantes mecanismos de virulência de C. albicans, fornecendo evidências que S. mutans produz substâncias com ação antifúngica, tornando-o promissor na busca de novos compostos antimicrobianos para prevenção e tratamento das candidoses humanas(AU)

The biofilm formation and hyphae production by Candida albicans are important virulence factors, mainly for mucosal adhesion and tissue invasion. The search for secondary metabolites produced by S. mutans is of great importance, since it may provide new therapeutic strategies against Candida infections, enabling the development of drugs that inhibit the mechanisms of pathogenicity of the species of this genus. Thus, the objective of this study was to obtain the crude extract and fractions from the supernatant of the 4 h culture of S. mutans (UA159) and evaluate their effects on the mechanisms of pathogenicity of C. albicans (ATCC18804) through in vitro studies. After culture of S. mutans, the crude extract was obtained via liquid-liquid partition with ethyl acetate (3x) and then fractionated on a C-18 derivatized silica column eluted with MeOH:H2O gradient, providing five fractions (SM-F1, SM-F2, SM-F3, SM-F4 and SM-F5). The identification of the substances contained in the crude extract and fractions was performed by gas chromatography coupled to mass spectrometry (GC-MS). The following substances were found: octanoic acid and uridine in crude extract, propanoic acid, (3R) -3-methyl -1,4-bis (trimethylsilyl) piperazine-2,5-dione, pyrimidine, gulose and oleamide in SM-F1 and nicotinic acid and tryptophan in SM-F2. The crude extract and fractions were submitted to bioactivity assays on hyphae formation by C. albicans and analyzed by optical microscopy and scanning electron microscopy (SEM). The crude extract and SM-F2 fraction, which resulted in highest inhibition of hyphae, were investigated in the expression of C. albicans genes involved in the filamentation mechanism (CPH1, EFG1, HWP1, UME6 and YWP1) by quantitative real-time PCR (RT-qPCR). In addition, the potential of inhibition of the crude extract, SM-F1 and SM-F2 fractions in biofilms of C. albicans were evaluated by the quantification of viable cells (CFU/mL) and SEM. The data obtained were statistically analyzed by Graph Pad Prism 5.0, with a significance level of 5%. The results demonstrated a significant inhibition on C. albicans hyphae formation by the crude extract and mainly by SMF2, with significant alterations in the expression of all genes analyzed. The crude extract and SM-F2 negatively regulated the expression of the CPH1, EFG1, HWP1 and UME6 genes, in contrast, positively regulated the expression of the YWP1 gene, involved in the mechanism of yeast dispersion. In the CFU/mL analyzes, the results showed a reduction in the counts of C. albicans in the biofilms formed when in contact with the crude extract, SM-F1 and SM-F2 fractions in all tested concentrations and the crude extract totally reduced C. albicans cells at 15 mg/mL concentration. The results of our study demonstrated that the crude extract and fractions of S. mutans presented inhibitory effects on important mechanisms of virulence of C. albicans, providing evidence that S. mutans produces substances with antifungal action, making it promising in the search for new compounds antimicrobials for the prevention and treatment of human candidoses(AU)

Avaliação das propriedades físicas e biológicas de materiais restauradores bioativos / Bioactive restorative materials: physical and biological evaluation

Materiais restauradores denominados bioativos se propõem a auxiliar no equilíbrio biodinâmico entre os dentes e a saliva. O objetivo deste estudo, portanto, foi avaliar quatro desses materiais quanto à: adesão bacteriana e microdureza do esmalte adjacente a restaurações realizadas com esses materiais quando submetidos ao desafio cariogênico. Para a adesão bacteriana foram confeccionados 10 espécimes padronizados de cada material restaurador que foram expostos em uma cepa padrão de Streptococcus mutans (UA 159). Depois da incubação foi determinado o número de unidades formadoras de colônia (UFC/mL). Para a avaliação da microdureza foram utilizados 91 incisivos bovinos distribuídos em 7 grupos (n=13): 2 grupos controle; ES, esmalte hígido sem ciclagem de pH e EC, esmalte com ciclagem de pH e 5 grupos com preparos padronizados de classe V na superfície do esmalte vestibular, restaurados com dos materiais selecionados: AB, ActivaBioactive (Pulpdent); BB, Beautifil Bulk (Shofu); CN, Cention N (Ivoclar Vivadent); EF, Equia Forte (GC) e FB, Filtek Bulk Fill (3M ESPE). A microdureza das superfícies do esmalte foi medida em um microdurômetro acoplado a um software para análise de imagem. Os resultados foram submetidos aos testes ANOVA e Tukey (5%). Para a adesão bacteriana os resultados demonstraram que não houve diferença estatística entre a resina composta convencional Filtek Bulk (10,58 ± 0,04) e os materiais bioativos Activa Bioactive (10,19 ± 0,08) e Cention N (10,16 ± 0,12). No entanto, pôde ser observado que esses materiais apresentaram diferença significativa com relação aos materiais Beautifil Bulk (9,66 ± 0,09) e Equia Forte (7,75 ± 1,27); que apresentou a menor adesão bacteriana. A análise dos dados de microdureza mostrou diferença entre tratamento e tempo (p<0,001) e na interação entre esses dois fatores. Os grupos: esmalte ciclado (77,89 ± 45,19) e resina composta Filtek Bulk (121,32 ± 43,53) apresentaram os menores valores de microdureza, seguido do grupo Beautifil Bulk (155,33 ± 57,35), diferindo significativamente dos demais grupos. Os resultados permitiram concluir que os materiais bioativos apresentaram interferência na adesão bacteriana, com a menor adesão proporcionada pelo cimento de ionômero de vidro; e também que, materiais que apresentam em sua composição íons que interagem com a estrutura dental melhoram a microdureza do esmalte adjacente às restaurações(AU)

Bioactive restorative materials are intended to aid the biodynamic balance between teeth and saliva. The objective of this study was to evaluate four of these materials for bacterial adhesion and microhardness of the enamel adjacent to restorations with them, when submitted to cariogenic challenge. For bacterial adhesion, 10 standardized specimens of each restorative material were prepared and exposed in a standard strain of Streptococcus mutans (UA 159). After incubation, the number of colony forming units (CFU / mL) was determined. To evaluate the microhardness, 91 bovine incisors were distributed in 7 groups (n = 13): 2 control groups; ES, enamel without pH cycling and EC, enamel with pH cycling and 5 groups that received standardized class V preparations on the buccal enamel surface restored with one of the selected materials: AB, ActivaBioactive (Pulpdent); BB, Beautifil Bulk (Shofu); CN, Cention N (Ivoclar Vivadent); EF, Equia Forte (GC) and, FB, Filtek Bulk Fill (3M ESPE). Enamel surfaces microhardness was measured in a microdurometer coupled to software for image analysis. The results were submitted to ANOVA and Tukey tests (5%). For bacterial adhesion the results showed that there was no statistical difference between the composite resin Filtek Bulk (10,58 ± 0,04) and the bioactive materials, Activa Bioactive (10,19 ± 0,08) and Cention N (10,16 ± 0,12). However, it was observed that these materials presented significant difference in relation to Beautifil Bulk (9,66 ± 0,09) and Equia Forte (7,75 ± 1,27); which presented the lowest bacterial adhesion. The analysis of microhardness data showed a difference between treatment and time (p <0.001) and in the interaction of these two factors. The groups: pH cycled enamel (77,89 ± 45,19) and Filtek Bulk resin (121,32 ± 43,53) presented the lowest microhardness values, followed by the Beautifil Bulk group (155,33 ± 57,35), differing significantly from the other groups. The results allowed to conclude that the bioactive materials interfered in the bacterial adhesion, with the lower adhesion provided by the glass ionomer cement; and also that, materials with ions that interact with the dental structure in their composition improve the microhardness of the enamel adjacent to the restorations(AU)

Estudio in vitro del Efecto Antibacteriano de la Oleorresina de Copaifera reticulata y el Aceite Esencial de Origanum majoricum Frente a Streptococcus mutans y Enterococcus Faecalis Bacterias de Importancia en Patologías Orales / In vitro Study of the Antibacterial Effect of Oleoresin of Copaifera reticulata and the Essential Oil of Origanum majoricum against Streptococcus mutans and Enterococcus faecalis Bacteria of Importance in Oral Pathologies

RESUMEN: El objetivo del estudio fue determinar el efecto antibacteriano in vitro de la oleorresina de Copaifera reticulata (C. reticulata) "copaiba" y del aceite esencial de Oreganum majoricum (O. majoricum) "orégano" frente a Streptococcus mutans (S. mutans) y Enterococcus faecalis (E. faecalis). Se desarrollaron pruebas de sensibilidad activando primero las cepas bacterias a enfrentar. La oleorresina de copaiba fue diluida con dimetilsulfósido (DMSO), obteniéndose al final concentraciones a probar de 100 %, 50 %, 25 %, y 12,5 %. En relación al aceite esencial de orégano este se probó solamente al 100 %. Para la prueba de difusión en agar con discos, se tomaron inóculos 100 µL de cada cepa bacteriana a una turbidez de 0,5 de Mc Farlam, para ser sembrados por diseminación en placas de tripticasa soya agar, para luego colocar los discos de forma equidistante cargados con las diferentes concentraciones de los productos naturales, se utilizaron como control positivo a la clorhexidina al 0,12 % y al DMSO como control negativo. Se incubaron las placas por el método de la vela en extinción a 37 °C, por un periodo de 24 horas, pasado el tiempo se realizó la lectura de los halos de inhibición. Los resultados obtenidos por la copaiba, determinaron un efecto antibacteriano en sus cuatro concentraciones, siendo los mayores halos de inhibición a la concentración del 100 %, copaiba genero mayores halos promedios para S, mutans de 30,00 ± 0,00 mm y para E. faecalis de 8,3 ± 0,50 mm. Para el caso del orégano se producen halos a la concentración del 100 % con un promedio de 25,3 ± 0,96 mm para S. mutans y para E. faecalis de 9,5 ± 1,29 mm. Se concluye del estudio que tanto copaiba como el orégano presentan un efecto antibacteriano para ambas bacterias, siendo su mayor efecto antibacteriano para ambos productos naturales sobre S. mutans.

ABSTRACT: The objective of the study was to determine the in vitro antibacterial effect of the oleoresin of Copaifera reticulata (C. reticulata) "copaiba" and of the essential oil of Oreganum majoricum (O. majoricum) "oregano" against Streptococcus mutans (S. mutans) and Enterococcus faecalis (E. faecalis). Sensitivity tests were developed by first activating the bacteria strains to be confronted. The oleoresin of copaiba was diluted with dimethylsulphoside (DMSO), obtaining final concentrations to be tested of 100 %, 50 %, 25 %, and 12.5 %. In relation to the essential oil of oregano, it was only 100 % tested. For the disk agar diffusion test, 100 mL of each bacterial strain was taken at a turbidity of 0.5 of Mc Farlam, to be planted by dissecting trypticase soy agar plates, and then placing the disks equidistantly loaded with the different concentrations of natural products; 0.12 % chlorhexidine was used as a positive control and DMSO as negative control. The plates were incubated by the candle method in extinction at 37 °C, for a period of 24 hours, after which time the inhibition halos were read. The results obtained by the copaiba, determined an antibacterial effect in its four concentrations, being the biggest halos of inhibition at the concentration of 100 %, copaiba genus higher average halos for S. mutans of 30.00 ± 0.00 mm and for E. faecalis of 8.3 ± 0.50 mm. In the case of oregano, haloes are produced at a concentration of 100 % with an average of 25.3 ± 0.96 mm for S. mutans and for E. faecalis 9.5 ± 1.29 mm. It is concluded from the study that both copaiba and oregano present an antibacterial effect for both bacteria, being its greater antibacterial effect for both natural products on S. mutans.

Influence of a preschool preventive dental programme on caries prevalence, oral care and secretory immunity to Streptococcus mutans in young adults.

OBJECTIVE: To evaluate oral hygiene habits, decayed, missing and filled teeth (DMFT) and surfaces (DMFS), dental care, dietetic habits and anti-Streptococcus mutans salivary secretory Immunoglobulin A (SIgA) in young adults who attended a preventive programme during preschool age. MATERIAL AND METHODS: The study group (Baby Clinic) comprised 72 patients, aged 18-25 years, who had participated in the Baby Clinic preventive programme. The control group was age- and gender-matched. The patients were examined and unstimulated whole saliva was sampled for detection of anti-S. mutansSIgA antibodies. RESULTS: Control patients presented increased DMFS scores (P < .05). Hygiene habits, cariogenic diet and antibody levels were not different between groups (P > .05). Baby Clinic patients presented better periodontal status (P < .005), less calculus (P < .005) and bleeding on probing (P < .005), and reported visiting dental services more regularly (P < .05). Adjusted multivariate linear regression analysis demonstrated that DMFT was associated with study group (P < .05), gender (P < .05), parents' education (P < .05), carbohydrate intake (P < .001) and levels of anti-S. mutansSIgA (P < .007). DMFS was associated with time elapsed since the last visit to the dentist (P < .005) and weekly carbohydrate intake (P < .005). CONCLUSION: Preventive programmes for preschool children positively impact on DMFS and periodontal status in young adults, but have no long-term effects on dietary or hygiene habits.

Atividade antifúngica do extrato bruto e frações de Streptococcus mutans sobre Candida albicans em modelos de estudo in vivo / Antifungal activity of crude extract and fractions of Streptococcus mutans on Candida albicans in models of in vivo study

Estudos realizados in vitro tem demonstrado que Streptococcus mutans podem produzir metabólitos capazes de inibir Candida albicans, tornando interessante a identificação e desenvolvimento de novas substâncias para o tratamento da candidose bucal. Assim, o objetivo desse estudo foi extrair, fracionar e identificar as substâncias produzidas por S. mutans e avaliar seus efeitos sobre a patogenicidade de C. albicans e na resposta imunológica em modelos de estudo in vivo. As substâncias do sobrenadante da cultura de S. mutans foram extraídas com acetato de etila e posteriormente fracionadas em coluna de sílica derivatizada C-18 (150 g, Φ = 3,5 cm) utilizando diferentes soluções de MeOH:H2O (36:64, 49:51, 60:40, 76:24, 100:0) como eluente, obtendo cinco diferentes frações (SM-F1, SM-F2, SMF3, SM-F4 e SM-F5). A identificação das substâncias contidas no extrato bruto e frações foi realizada por cromatografia gasosa acoplada a espectrometria de massas. Foram testados os efeitos do extrato bruto e frações do sobrenadante da cultura de S. mutans sobre a candidose experimental induzida em modelo invertebrado de Galleria mellonella e em camundongos imunossuprimidos. Para a escolha da concentração a ser testada nos modelos in vivo foi realizada a determinação da Concentração Inibitória Mínima do extrato bruto e frações sobre C. albicans. No modelo de infecção experimental com G. mellonella, os efeitos do extrato e frações foram analisados pelos testes de curva de sobrevivência, quantificação de UFC/mL de C. albicans na hemolinfa e determinação da densidade hemocitária das larvas de G. mellonella. O extrato, assim como as frações com melhores resultados em modelo de invertebrado foram selecionados para o estudo de candidose bucal em camundongos. Nesse modelo experimental, o desenvolvimento de candidose foi avaliado pelos testes de recuperação e determinação de UFC/mL de C. albicans da cavidade bucal, análise macroscópica e microscópica do dorso da língua. Os dados obtidos foram analisados estatisticamente pelo Programa Graph Pad Prism 5.0, com nível de significância de 5%. Na determinação da concentração inibitória mínima, apenas o extrato bruto e a fração SM-F2 demonstraram efeito sobre C. albicans, sendo 10 mg/mL e 15mg/mL, respectivamente. No modelo de G. mellonella não houve aumento da sobrevida das larvas com a utilização profilática do extrato, ocorrendo 100% de morte nas primeiras 24 h em ambos os grupos com infecção. No entanto, ao realizarmos o tratamento pós-infecção com o extrato bruto houve um aumento da sobrevida em 18,75 a 25%. Como não houve efeito profilático para o extrato bruto, as frações foram administradas apenas terapeuticamente, verificando-se aumento da sobrevida das larvas com as fração SM-F1 e SM-F2. Na contagem de UFC/mL de C. albicans na hemolinfa das larvas, foi verificada diferença estatisticamente significante apenas com o extrato bruto e fração SM-F2 após 12 h de infecção Em relação a densidade hemocitária, os grupos tratados com extrato bruto e frações (SM-F1 e SM-F2) apresentaram maior número de hemócitos circulantes na hemolinfa em relação ao grupo apenas infectado com C. albicans. Portanto, as frações SM-F1 e SM-F2 foram escolhidas para os testes em camundongos. Nesse modelo de estudo, verificou-se que o extrato bruto, SM-1 e SM-F2 foram capazes de reduzir significamente o número de UFC/mL de Candida na cavidade bucal e as lesões de candidose no dorso da língua, sendo esses efeitos mais proeminentes para SM-F2. Assim, concluiu-se que as frações SM-F1 e SM-F2 do extrato de S. mutans contêm substâncias antifúngicas com ação terapêutica sobre a candidose experimental, podendo ser alvos de novas estratégias terapêuticas para a candidose bucal(AU)

In vitro studies have shown that Streptococcus mutans can produce metabolites capable of inhibiting Candida albicans, becoming interesting the identification and development of new substances for the treatment of oral candidiasis. Thus, the objective of this study was to extract, fractionate and identify the substances produced by S. mutans and evaluate their effects on the pathogenicity of C. albicans and on the immune response in in vivo study models. Substances from the S. mutans culture supernatant were extracted with ethyl acetate and subsequently fractionated on a C-18 derivatized silica column (150 g, Φ = 3.5 cm) using different solutions of MeOH:H2O (36:64, 49:51, 60:40, 76:24, 100:0) as eluent, obtaining five different fractions (SM-F1, SM-F2, SM-F3, SM-F4 and SM-F5). The identification of the substances contained in the crude extract and fractions was performed by gas chromatography coupled to mass spectrometry (GC-MS). The crude extract products and the fractions of the supernatant of the S. mutans culture were assessed on experimental candidiasis induced in invertebrate model of Galleria mellonella and in immunosuppressed mice. For a choice of the concentration to be tested in the in vivo models, a determination of the Minimum Inhibitory Concentration (MIC) of the crude extract and fractions on C. albicans was performed. In the model of experimental infection with G. mellonella, the effects of extract and fractions were analyzed by the survival curve test, quantification of CFU/mL of C. albicans in hemolymph and determination of haemocyte density of G. mellonella larvae. The extract, as well as fractions with better results in invertebrate model were selected for the study of oral candidiasis in mice. In this experimental model, the development of candidiasis was evaluated by the tests of recovery and determination of CFU/mL of C. albicans from the mice's oral cavity, macroscopic and microscopic examination of the tongue dorsum. The data obtained were statistically analyzed by Graph Pad Prism 5.0, with a significance level of 5%. In the determination of the minimal inhibitory concentration, only the crude extract and the SM-F2 fraction showed effect on C. albicans, with 10 mg/mL and 15 mg/mL, respectively. In the model of G. mellonella there was no increase in the larvae survival with the prophylactic use of the extract, occurring 100% of death in the first 24 h in both groups with infection. However, when we performed the post infection treatment with the crude extract there was an increase in survival from 18.75 to 25%. As there was no prophylactic effect for the crude extract, the fractions were administered only therapeutically, verifying increased survival of the larvae with the SM-F1 and SM-F2 fraction. In the CFU/mL count of C. albicans on larval hemolymph, a statistically significant difference was observed only with crude extract and SM-F2 fraction after 12 h of infection. In relation to hemocyte density, the groups treated with crude extract and fractions (SM-F1 and SM-F2) had a higher number of hemocytes circulating in the hemolymph compared to the group only infected with C. albicans. Therefore, the fractions SM-F1 and SMF2 were chosen for the tests in mice. In this study model, it was verified that the crude extract, SM-F1 and SM-F2 were able to significantly reduce the number of CFU/mL of Candida in oral cavity and lesions of candidiasis of the tongue dorsum, these effects were more prominent for SM-F2. Thus, it was concluded that the SM-F1 and SM-F2 fractions of the S. mutans extract contain antifungal substances with therapeutic action on experimental candidiasis, being able to be targets of new therapeutic strategies for oral candidiasis(AU)

Efeitos de formulações probióticas contendo Lactobacillus paracasei 28. 4 sobre o crescimento, produção de polissacarídeos e formação de biofilmes de Streptococcus mutans / Effects of different probiotics formulations containing Lactobacillus paracasei 28. 4 on Streptococcus mutans growth, polysaccharides production and biofilms formation

O uso de probióticos como método de prevenção para a cárie dental tem sido amplamente investigado com resultados promissores. Portanto, torna-se necessário o desenvolvimento de formulações, para aplicação na cavidade bucal, que contenham cepas probióticas com atividade contra Streptococcus mutans. Assim, o objetivo desse projeto foi avaliar os efeitos antimicrobianos de formulações probióticas de Lactobacillus paracasei 28.4 sobre a atividade antibacteriana em crescimento planctônico, produção de polissacarídeos e formação de biofilmes de S. mutans. Inicialmente, a atividade antibacteriana de 3 diferentes formulações probióticas (concentrações de 0,5, 0,75 e 1% p/v de gellan gum em CaCl2) foram testadas em culturas planctônicas sobre cepas de S. mutans (cepa padrão UA 159 e 5 cepas clínicas). Os resultados demonstraram inibição total do crescimento das cepas de S. mutans quando tratadas com todas as formulações probióticas testadas. Nos estudos subsequentes, foram avaliados os efeitos profiláticos da formulação probiótica na concentração de 1% p/v nos biofilmes de 4 e 24 horas de S. mutans, utilizando-se a cepa UA 159 e 2 cepas clínicas. Por meio do método sulfúrico-antrona, foi observado que a aplicação da formulação probiótica reduziu a capacidade de produção de polissacarídeos extracelulares pelas cepas de S. mutans em aproximadamente 80% nos dois tempos dos biofilmes testados. A formulação probiótica também foi capaz de reduzir significativamente a biomassa total dos biofilmes de S. mutans nos testes de absorbância do Cristal Violeta, com redução média na leitura de densidade óptica de 2,15 ± 0,10 no tempo de 4 horas e 2,67 ± 0,25 no tempo de 24 horas. A seguir, os efeitos antimicrobianos da formulação probiótica foram avaliados em biofilmes de S. mutans formados sobre a superfície de discos de hidroxiapatita, encontrando-se reduções de 0,57 a 1,54 UFC (Log) na contagem de células viáveis de S. mutans nos grupos tratados em relação aos grupos controle. Também foi possível observar redução na quantidade de células de S. mutans aderidas aos discos de hidroxiapatita pela Microscopia Eletrônica de Varredura (MEV). Por fim, utilizando-se análise de Realtime PCR, foram testados os efeitos das formulações probióticas sobre a expressão de genes de virulência de S. mutans relacionados à adesão e formação do biofilme. Os resultados mostraram que na presença da formulação probiótica, os genes luxS, brpA, gbpB e gtfB de S. mutans foram negativamente regulados. Concluiu-se que a formulação probiótica contendo L. paracasei 28.4 em gellan gum apresentou efeitos inibitórios sobre o crescimento planctônico e biofilme de S. mutans, interferindo na produção de polissacarídeos extracelulares, quantidade de biomassa total, viabilidade celular, aderência de células à hidroxiapatita e transcrição de genes de virulência(AU)

The use of probiotics as a prevention method for dental caries has been extensively investigated with promising results. Therefore, it becomes necessary to develop formulations, for application in the oral cavity, containing probiotic strains with activity against Streptococcus mutans. Thus, the objective of this project was to evaluate the antimicrobial effects of probiotic formulations of Lactobacillus paracasei 28.4 on the antibacterial activity in planktonic growth, polysaccharide production and biofilms formation of S. mutans using reference and clinical strains. Firstly, antibacterial activity of 3 different probiotic formulations (concentrations of 0.5, 0.75 and 1% w/v of gellan gum in CaCl 2) were tested in planktonic cultures on S. mutans strains (standard strain UA 159 and 5 clinical strains). The results demonstrated complete inhibition of S. mutans strains growth when treated with all probiotic formulations tested. In the subsequent studies, the prophylactic effects of the 1% w/v probiotic formulation on 4 and 24 hours S. mutans biofilms were evaluated using the UA 159 strain and 2 clinical strains. Using the sulfuric-anthrone method, it was observed that the application of the probiotic formulation reduced the production capacity of extracellular polysaccharides by S. mutans strains in approximately 80% in both times of the biofilms tested. The probiotic formulation was also able to significantly reduce the total biomass of S. mutans biofilms in the Crystal Violet absorbance tests, with a mean reduction in the optical density reading of 2.15 ± 0.10 in 4 hours and 2.67 ± 0.25 in 24 hours. Next, the antimicrobial effects of the probiotic formulation were evaluated in S. mutans biofilms formed on the surface of hydroxyapatite discs, with reductions of 0.57 to 1.54 CFU (Log) in the viable cells count of S. mutans in the treated groups compared to the control groups. It was also possible to observe a reduction in the amount of S. mutans cells adhered to the hydroxyapatite disks by Scanning Electron Microscopy (SEM). Finally, using Realtime PCR analysis, the effects of probiotic formulations on the expression of S. mutans virulence genes related to adhesion and biofilm formation were tested. The results showed that in the presence of the probiotic formulation, the luxS, brpA, gbpB and gtfB genes of S. mutans were down regulated. It was concluded that the probiotic formulation containing L. paracasei 28.4 in gellan gum presented inhibitory effects on planktonic growth and S. mutans biofilm, interfering in the production of extracellular polysaccharides, amount of total biomass, cell viability, cell adhesion to hydroxyapatite and transcription of virulence genes(AU)

Comparisons of IgA response in saliva and colostrum against oral streptococci species.

The present study compared IgA specificity against oral streptococci in colostrum and saliva samples. Sixty-two mother-and-child pairs were included; samples of colostrum (C) and saliva (MS) were collected from the mothers and saliva samples were collected from babies (BS). The specificity of IgA against Streptococcus mutans and S. mitis were analyzed by western blot. Only 30% of babies' samples presented IgA reactivity to S. mutans, while 74 and 80% of MS and C, respectively, presented this response. IgA reactivity to S. mutans virulence antigens (Ag I/II, Gtf and GbpB) in positive samples showed differences between samples for Gtf and especially for GbpB (p < 0.05), but responses to Ag I/II were similar (p > 0.05). The positive response of Gtf-reactive IgA was different between C (90%) and MS (58%) samples (p < 0.05), but did not differ from BS (p > 0.05). GbpB was the least detected, with 48 and 26% of C and MS, and only 5% of BS samples presenting reactivity (p > 0.05). Eight percent of MS and C samples presented identical bands to SM in the same time-point. In conclusion, the differences of IgA response found between C and MS can be due to the different ways of stimulation, proliferation and transportation of IgA in those secretions. The colostrum has high levels of IgA against S. mutans virulence antigens, which could affect the installation and accumulation process of S. mutans, mainly by supplying anti-GbpB IgA to the neonate.

The two-component system VicRK regulates functions associated with Streptococcus mutans resistance to complement immunity.

Streptococcus mutans, a dental caries pathogen, can promote systemic infections upon reaching the bloodstream. The two-component system (TCS) VicRKSm of S. mutans regulates the synthesis of and interaction with sucrose-derived exopolysaccharides (EPS), processes associated with oral and systemic virulence. In this study, we investigated the mechanisms by which VicRKSm affects S. mutans susceptibility to blood-mediated immunity. Compared with parent strain UA159, the vicKSm isogenic mutant (UAvic) showed reduced susceptibility to deposition of C3b of complement, low binding to serum immunoglobulin G (IgG), and low frequency of C3b/IgG-mediated opsonophagocytosis by polymorphonuclear cells in a sucrose-independent way (P<.05). Reverse transcriptase quantitative polymerase chain reaction analysis comparing gene expression in UA159 and UAvic revealed that genes encoding putative peptidases of the complement (pepO and smu.399) were upregulated in UAvic in the presence of serum, although genes encoding murein hydrolases (SmaA and Smu.2146c) or metabolic/surface proteins involved in bacterial interactions with host components (enolase, GAPDH) were mostly affected in a serum-independent way. Among vicKSm -downstream genes (smaA, smu.2146c, lysM, atlA, pepO, smu.399), only pepO and smu.399 were associated with UAvic phenotypes; deletion of both genes in UA159 significantly enhanced levels of C3b deposition and opsonophagocytosis (P<.05). Moreover, consistent with the fibronectin-binding function of PepO orthologues, UAvic showed increased binding to fibronectin. Reduced susceptibility to opsonophagocytosis was insufficient to enhance ex vivo persistence of UAvic in blood, which was associated with growth defects of this mutant under limited nutrient conditions. Our findings revealed that S. mutans employs mechanisms of complement evasion through peptidases, which are controlled by VicRKSm.

Comparisons of IgA response in saliva and colostrum against oral streptococci species

Abstract The present study compared IgA specificity against oral streptococci in colostrum and saliva samples. Sixty-two mother-and-child pairs were included; samples of colostrum (C) and saliva (MS) were collected from the mothers and saliva samples were collected from babies (BS). The specificity of IgA against Streptococcus mutans and S. mitis were analyzed by western blot. Only 30% of babies’ samples presented IgA reactivity to S. mutans, while 74 and 80% of MS and C, respectively, presented this response. IgA reactivity to S. mutans virulence antigens (Ag I/II, Gtf and GbpB) in positive samples showed differences between samples for Gtf and especially for GbpB (p < 0.05), but responses to Ag I/II were similar (p > 0.05). The positive response of Gtf-reactive IgA was different between C (90%) and MS (58%) samples (p < 0.05), but did not differ from BS (p > 0.05). GbpB was the least detected, with 48 and 26% of C and MS, and only 5% of BS samples presenting reactivity (p > 0.05). Eight percent of MS and C samples presented identical bands to SM in the same time-point. In conclusion, the differences of IgA response found between C and MS can be due to the different ways of stimulation, proliferation and transportation of IgA in those secretions. The colostrum has high levels of IgA against S. mutans virulence antigens, which could affect the installation and accumulation process of S. mutans, mainly by supplying anti-GbpB IgA to the neonate.

Propolis modulates miRNAs involved in TLR-4 pathway, NF-κB activation, cytokine production and in the bactericidal activity of human dendritic cells.

OBJECTIVES: Dendritic cells (DCs) are antigen-presenting cells, essential for recognition and presentation of pathogens to T cells. Propolis, a resinous material produced by bees from various plants, exhibits numerous biological properties, highlighting its immunomodulatory action. Here, we assayed the effects of propolis on the maturation and function of human DCs. METHODS: DCs were generated from human monocytes and incubated with propolis and LPS. NF-κB and cytokines production were determined by ELISA. microRNA's expression was analysed by RT-qPCR and cell markers detection by flow cytometry. Colony-forming units were obtained to assess the bactericidal activity of propolis-treated DCs. KEY FINDINGS: Propolis activated DCs in the presence of LPS, inducing NF-kB, TNF-α, IL-6 and IL-10 production. The inhibition of hsa-miR-148a and hsa-miR-148b abolished the inhibitory effects on HLA-DR and pro-inflammatory cytokines. The increased expression of hsa-miR-155 may be correlated to the increase in TLR-4 and CD86 expression, maintaining LPS-induced expression of HLA-DR and CD40. Such parameters may be involved in the increased bactericidal activity of DCs against Streptococcus mutans. CONCLUSION: Propolis modulated the maturation and function of DCs and may be useful in the initial steps of the immune response, providing a novel approach to the development of DC-based strategies and for the discovery of new immunomodulators.

Relationship between the IgA antibody response against Streptococcus mutans GbpB and severity of dental caries in childhood.

OBJECTIVE: Explore the associations between the severity of dental caries in childhood, mutans streptococci (MS) levels and IgA antibody response against Streptococcus mutans GbpB. Moreover, other caries-related etiological factors were also investigated. DESIGN: 36-60 month-old children were grouped into Caries-Free (CF, n=19), Early Childhood Caries (ECC, n=17) and Severe Early Childhood Caries (S-ECC, n=21). Data from socio-economic-cultural status, oral hygiene habits and dietary patterns were obtained from a questionnaire and a food-frequency diary filled out by parents. Saliva was collected from children for microbiological analysis and detection of salivary IgA antibody reactive with S. mutans GbpB in western blot. RESULTS: S-ECC children had reduced family income compared to those with ECC and CF. There was difference between CF and caries groups (ECC and S-ECC) in MS counts. Positive correlations between salivary IgA antibody response against GbpB and MS counts were found when the entire population was evaluated. When children with high MS counts were compared, S-ECC group showed significantly lower IgA antibody levels to GbpB compared to CF group. This finding was not observed for the ECC group. CONCLUSIONS: This study suggests that children with S-ECC have reduced salivary IgA immune responses to S. mutans GbpB, potentially compromising their ability to modify MS infection and its cariogenic potential. Furthermore, a reduced family income and high levels of MS were also associated with S-ECC.

Salivary profile in diabetic patients: biochemical and immunological evaluation.

BACKGROUND: The aim of this study was to evaluate the biochemical and immunological characteristics of saliva from diabetic patients compared to non-diabetic adults. METHODS: Eighty-eight diabetic adults and 39 non-diabetic adults (control) were included in the study. Glucose, urea, calcium, total protein and amylase were determined by a colorimetric method. The levels of secretory IgA and the IgA anti-Streptococcus mutans and anti-insulin IgA antibodies were measured by enzyme-linked immunosorbent assay (ELISA). Caries status was evaluated using the DMFT index. RESULTS: Glucose, urea, calcium, anti-S. mutans IgA, total IgA, and anti-insulin IgA were significantly higher in diabetic patients, whereas total protein and amylase levels were lower in these patients. There was no positive correlation between blood and salivary glucose levels in either group. Diabetic patients had a higher DMFT index. CONCLUSIONS: The present study showed for the first time that IgA levels in diabetic patients'saliva, shows correlation with systemic biochemical parameters. Thus the saliva is an useful tool to follow the systemic health status in these patients.