Genetic Polymorphism Of Streptococcus Mutans Strains Associated With Incomplete Caries Removal

Aim: Despite the antibacterial properties of dental materials, the survival of residual bacteria under restorations has been demonstrated after incomplete caries removal. The aim of this study was to evaluate the genetic polymorphism of Streptococcus mutans strains isolated from deep dentinal lesions before and three months after incomplete caries removal. Methods: Samples of carious dentin were collected from 33 primary and/or permanent molars before and after indirect pulp treatment and processed for microbiological isolation of mutans streptococci (MS). After three months of the dental treatment, positive cultures for MS were detected in only ten of these teeth. DNA of MS isolates were obtained and subjected to polymerase chain reaction (PCR) for identification of Smutans. The arbitrary primed-PCR method (primer OPA-13) was used to detect the genetic polymorphism of S. mutans strains. Results: Identical or highly related S. mutans genotypes were observed in each tooth, regardless of the collect. Considering each tooth separately, a maximum of nine genotypic patterns were found in each tooth from all the collects. In addition, at least one genotypic pattern was repeated in the three collects. Genetic diversity was observed among the S. mutans isolates, obtained from different teeth after three months of the dental treatment. Conclusions: The persistence of identical genotypic patterns and the genetic similarity among the isolates, from the same tooth in distinct collects, showed the resistance of some S. mutans strains after incomplete caries removal treatment.812-

Oral Condition of Adolescents who Participated in an Oral Health Program During the First Decade of Life

Objective: To evaluate the oral health of adolescents who participated in an oral health preventive program during the first decade of life. Material and Methods: For the evaluation of dental caries and gingival condition, DMFT and Community Periodontal Index were used, both recommended by the World Health Organization. To verify the occurrence of dental fluorosis, the Dean index was used. Results: Data collection was obtained from 252 patients aged 12 to 16 years. The average DMFT index was 1.14; in relation to the gingival condition, the index of healthy gingival tissue prevailed and the average of this value was 84%, with code 0 being more registered in tooth 11, code 1, more frequently in teeth 16/17 and 36/37 and for last, code 2, in tooth 31 most frequently. Dean\u27s index showed a percentage of 89% of patients without clinical signs of dental fluorosis. Conclusion: Adolescents participating in an oral health preventive program in the first decade of life exhibited very satisfactory results regarding the prevention of caries disease, healthy periodontal condition and reduced prevalence of dental fluorosis

Interplay among the oral microbiome, oral cavity conditions, the host immune response, diabetes mellitus, and its associated-risk factors : an overview

This comprehensive review of the literature aimed to investigate the interplay between the oral microbiome, oral cavity conditions, and host immune response in Diabetes mellitus (DM). Moreover, this review also aimed to investigate how DM related risk factors, such as advanced age, hyperglycemia, hyperlipidemia, obesity, hypertension and polycystic ovary syndrome (PCOS), act in promoting or modifying specific mechanisms that could potentially perpetuate both altered systemic and oral conditions. We found that poorly controlled glycemic index may exert a negative effect on the immune system of affected individuals, leading to a deficient immune response or to an exacerbation of the inflammatory response exacerbating DM-related complications. Hyperglycemia induces alterations in the oral microbiome since poor glycemic control is associated with increased levels and frequencies of periodontal pathogens in the subgingival biofilm of individuals with DM. A bidirectional relationship between periodontal diseases and DM has been suggested: DM patients may have an exaggerated inflammatory response, poor repair and bone resorption that aggravates periodontal disease whereas the increased levels of systemic pro-inflammatory mediators found in individuals affected with periodontal disease exacerbates insulin resistance. SARSCoV-2 infection may represent an aggravating factor for individuals with DM. Individuals with DM tend to have low salivary flow and a high prevalence of xerostomia, but the association between prevalence/experience of dental caries and DM is still unclear. DM has also been associated to the development of lesions in the oral mucosa, especially potentially malignant ones and those associated with fungal infections. Obesity plays an important role in the induction and progression of DM. Co-affected obese and DM individuals tend to present worse oral health conditions. A decrease in HDL and, an increase in triglycerides bloodstream levels seem to be associated with an increase on the load of periodontopathogens on oral cavity. Moreover, DM may increase the likelihood of halitosis. Prevalence of impaired taste perception and impaired smell recognition tend to be greater in DM patients. An important interplay among oral cavity microbiome, DM, obesity and hypertension has been proposed as the reduction of nitrate into nitrite, in addition to contribute to lowering of blood pressure, reduces oxidative stress and increases insulin secretion, being these effects desirable for the control of obesity and DM. Women with PCOS tend to present a distinct oral microbial composition and an elevated systemic response to selective members of this microbial community, but the association between oral microbiome, PCOS are DM is still unknown. The results of the studies presented in this review suggest the interplay among the oral microbiome, oral cavity conditions, host immune response and DM and some of the DM associated risk factors exist. DM individuals need to be encouraged and motivated for an adequate oral health care. In addition, these results show the importance of adopting multidisciplinary management of DM and of strengthening physicians-dentists relationship focusing on both systemic and on oral cavity conditions of DM patients

Avaliação da qualidade das máscaras comercializadas no Brasil em tempos de pandemia da COVID-19 quanto à presença de prata e de nanopartículas de prata

Introduction: The COVID-19 pandemic caused by the new coronavirus is a disease without  specific treatment and has become one of the great challenges of the current century. One of the alternatives to minimize the direct transmission rate of the virus is the use of face masks. Currently, there is a diversity of masks on the market, both in the textile composition and in  the presence or absence of the silver (Ag) element, in the form of ions or silver nanoparticles (AgNP), which have biocidal activity. Objective: To evaluate the presence of total Ag and AgNP in masks produced to protect the population from COVID-19 being sold in Brazil during the  pandemic. Method: This is a cross-sectional descriptive observational study with convenience sampling. The samples were analyzed by ICP-MS in the standard mode and in the single article mode. Results: The concentrations of total Ag in the studied samples varied from 14 to 72 μgg-1. It was observed that 50% of the evaluated samples that claim to have AgNP had a size distribution between 17 and 57 nm. When subjected to the washing cycles, there was a reduction in the concentration of Ag, which raises the question as to its real biocidal effectiveness over time. Conclusions: The data generated can provide the current scenario of the concentration of silver in the masks and thus assess the potential benefit or risk of use for human and environmental health. In addition, this knowledge can provide technical-scientific support for the sanitary inspection of quality control and implementation of regulatory standards in this field of activity.   Introdução: A pandemia COVID-19 causada pelo novo coronavírus é uma doença sem tratamento  específico que se tornou um dos grandes desafios do século atual. Uma das alternativas para minimizar a taxa de transmissão direta do vírus é o uso das máscaras faciais. Atualmente, há no mercado uma diversidade de máscaras, tanto na composição têxtil, quanto na presença ou não do elemento prata (Ag), sob a forma de íon ou nanopartículas de prata (AgNP), que possui atividade biocida. Objetivo: Avaliar a presença da Ag total e de AgNP em máscaras produzidas para proteger a população da COVID-19 que estão sendo comercializadas no Brasil durante a pandemia. Método: O desenho utilizado para o estudo foi observacional descritivo do tipo transversal com amostragem por conveniência. As amostras foram analisadas por ICP-MS no modo padrão e no modo single particle. Resultados: As concentrações de prata total nas amostras  estudadas apresentaram uma variação de 14–72 μgg-1. Foi observado que 50% das amostras avaliadas que declaram ter AgNP apresentaram uma distribuição de tamanho entre 17–57 nm. Ao serem submetidas aos ciclos de lavagem, verificou-se uma redução na concentração de Ag, a cada novo ciclo, o que levanta o questionamento quanto a sua real efetividade biocida ao longo do tempo. Conclusões: Os dados gerados fornecem o atual cenário da concentração de Ag nasmáscaras e, assim, avaliar o potencial benefício ou risco do uso para a saúde humana e ambiental. Além disso, este conhecimento pode dar subsídios técnico-científicos para a fiscalização sanitária do controle de qualidade e a implementação de normas regulatórias nesse ramo de atuação.

Nanomedicamentos: regulamentação e controle de qualidade

Introduction:The use of knowledge from nanotechnology in the pharmaceutical industry has led to the production of new drugs with their own therapeutic and toxicological characteristics. Controlled-release drugs that act directly on their action places, reducing their potential side effects, have been produced at the expense of this technology. With sizes comparable to those of biological entities and unique properties, this new class of drugs, the nanodrugs still presents some gaps that hinder its regulation. Objective: To evaluate these gaps, their impacts in the regulation and quality areas and the new regulation approaches under study. Method:A data survey was carried out in the electronic databases MEDLINE, PubMed and SCIELO, searching for original indexed articles, in Portuguese or in English, since 2002 until 2020. Relevant search terms in both languages were used (“Nanomedication”, “nanomedicine regulation”, “nanocarriers”, “nanomedicine”, “nanotechnology drugs”, “quality and safety by the procedure” and “nanomedicine health surveillance”). Results:The selected works describe the current moment of regulation and quality control of these nanoproducts, as well as highlight the problems that still require greater understanding. Conclusions:Nanotechnology applied to the formulation and manufacture of drugs is undoubtedly a great advance for health. However, there are several points that still require further development and that impact the regulatory frameworks for the registration, effectiveness and safety of these products.Introdução:A utilização dos  conhecimentos oriundos da nanotecnologia na indústria farmacêutica tem propiciado a produção de novos medicamentos com características terapêuticas e  toxicológicas próprias. Medicamentos de liberação controlada e que atuam diretamente em seus locais de ação, reduzindo seus potenciais efeitos colaterais, têm sido produzidos às custas desta tecnologia. Com tamanhos comparáveis aos de entidades biológicas e propriedades únicas, esta nova classe de medicamentos, os  nanomedicamentos, apesenta ainda algumas lacunas que dificultam sua regulação. Objetivo:Avaliar estas lacunas, seus impactos nas áreas de regulamentação e qualidade e as novas abordagens de regulamentação que estão em estudo. Método:Foi realizado um levantamento de dados nas bases de dados eletrônicas MEDLINE (PubMed) e SciELO, buscando artigos originais indexados, em português ou em inglês ou espanhol, a partir de 2002 até 2020. Foram utilizados termos de busca relevantes nas três línguas (“nanomedicamento”, “regulação de nanomedicamentos”, “nanocarreadores”, “nanomedicina”, “medicamentos com nanotecnologia”, “qualidade e segurança pelo procedimento” e “vigilância sanitária de nanomedicamentos”). Resultados: Os trabalhos selecionados descrevem o atual momento da regulamentação e do controle da qualidade desses nanoprodutos, bem como evidenciam os problemas que ainda requerem maior compreensão. Conclusões: A nanotecnologia aplicada à formulação e à fabricação de medicamentos constitui indubitavelmente um grande avanço para a saúde. No entanto, existem vários pontos que ainda requerem maior desenvolvimento e que impactam os marcos regulatórios para o registro, a eficácia e a segurança desses produtos

Synergistic antimicrobial potential of EGCG and fosfomycin against biofilms associated with endodontic infections

Objective: This study aimed to evaluate the cytotoxicity and synergistic effect of epigallocatechin gallate (EGCG) and fosfomycin (FOSFO) on biofilms of oral bacteria associated with endodontic infections. Methodology: This study determined minimum inhibitory and bactericidal concentration (MIC/MBC) and fractionated inhibitory concentration (FIC) of EGCG and FOSFO against Enterococcus faecalis, Actinomyces israelii, Streptococcus mutans, and Fusobacterium nucleatum. Monospecies and multispecies biofilms with those bacteria formed in polystyrene microplates and in radicular dentin blocks of bovine teeth were treated with the compounds and control chlorhexidine (CHX) and evaluated by bacterial counts and microscopy analysis. Toxicity effect of the compounds was determined on fibroblasts culture by methyl tetrazolium assays. Results: The combination of EGCG + FOSFO demonstrated synergism against all bacterial species, with an FIC index ranging from 0.35 to 0.5. At the MIC/FIC concentrations, EGCG, FOSFO, and EGCG+FOSFO were not toxic to fibroblasts. EGCG+FOSFO significantly reduced monospecies biofilms of E. faecalis and A. israelli, whereas S. mutans and F. nucleatum biofilms were eliminated by all compounds. Scanning electron microscopy of multispecies biofilms treated with EGCG, EGCG+FOSFO, and CHX at 100x MIC showed evident biofilm disorganization and substantial reduction of extracellular matrix. Confocal microscopy observed a significant reduction of multispecies biofilms formed in dentin tubules with 84.85%, 78.49%, and 50.6% of dead cells for EGCG+FOSFO, EGCG, and CHX at 100x MIC, respectively. Conclusion: EGCG and fosfomycin showed a synergistic effect against biofilms of oral pathogens related to root canal infections without causing cytotoxicity

Doxycycline-containing glass ionomer cement for arresting residual caries: an in vitro study and a pilot trial

In a previous study, we demonstrated that the incorporation of doxycycline hyclate (DOX) into resin-modified glass ionomer cement (RMGIC) inhibited important cariogenic microorganisms, without modifying its biological and mechanical characteristics. In this study, we keep focused on the effect of that experimental material as a potential therapy for arresting residual caries by analyzing other in vitro properties and conducting a pilot clinical trial assessing the in vivo effect of DOX-containing RMGIC on residual mutans streptococci after partial carious removal in primary molars. Specimens of the groups RMGIC (control); RMGIC + 1.5% DOX; RMGIC + 3% DOX; and RMGIC + 4.5% DOX were made to evaluate the effect of DOX incorporation on surface microhardness and fluoride release of RMGIC and against biofilm of Streptococcus mutans. Clinical intervention consisted of partial caries removal comparing RMGIC and RMGIC + 4.5% DOX as lining materials. After 3 months, clinical and microbiologic evaluations were performed. Data were submitted to ANOVA/Tukey or Wilcoxon/Mann-Whitney set as α=0.05. Fluoride release and surface microhardness was not influenced by the incorporation of DOX (p>0.05). There was a significant reduction of S. mutans biofilm over the material surface with the increase of DOX concentration. After clinical trial, the remaining dentin was hard and dry. Additionally, mutans streptococci were completely eliminated after 3 months of treatment with RMGIC + 4.5% DOX. The incorporation of DOX provided better antibiofilm effect, without jeopardizing fluoride release and surface microhardness of RMGIC. This combination also improved the in vivo shortterm microbiological effect of RMGIC after partial caries removal

Frequency of Porphyromonas gingivalis fimA in smokers and nonsmokers after periodontal therapy

Porphyromonas gingivalis is one of the most important Gram-negative anaerobe bacteria involved in the pathogenesis of periodontitis. P. gingivalis has an arsenal of specialized virulence factors that contribute to its pathogenicity. Among them, fimbriae play a role in the initial attachment and organization of biofilms. Different genotypes of fimA have been related to length of fimbriae and pathogenicity of the bacterium. Objectives: The aim of this study was to identify 5 types of fimA genotype strains in smokers and nonsmokers with periodontitis, before and after periodontal therapy. Material and Methods: Thirty-one patients with periodontitis harboring P. gingivalis were selected: 16 nonsmokers (NS) and 15 smokers (SM). Clinical and microbiological parameters were evaluated at baseline and 3 months after periodontal treatment, namely: plaque index, bleeding on probe, probing depth, gingival recession and clinical attachment level. The frequency of P. gingivalis and fimA genotype strains were determined by polymerase chain reaction. Results: Type I fimA was detected in the majority of SM and NS at baseline, and the frequency did not diminish after 3 months of treatment. The frequency of type II genotype was higher in SM than NS at baseline. After 3 months, statistical reduction was observed only for types II and V fimA genotypes in SM. The highest association was found between types I and II at baseline for NS (37.5%) and SM (53.3%). Conclusion: The most prevalent P. gingivalis fimA genotypes detected in periodontal and smoker patients were genotypes I and II. However, the presence of fimA genotype II was higher in SM. Periodontal treatment was effective in controlling periodontal disease and reducing type II and V P. gingivalis fimA

Evaluation of salt intended for human consumption for the presence of physical contaminants: microplastics an emerging contaminant in the food area

Introduction: The presence of physical contaminants in food goes against the guarantee of the supply of safe products for consumption. Currently, there is an environmental concern with this type of contamination, especially with a class of plastic particles less than 5 mm, called microplastics. The impacts on human organisms are still under discussion, but there is already a relationship between the ingestion and inhalation of these particles and a possible health risk, since, in addition to being derived from macroplatic degradation processes with varied chemical compositions, they can still carry other contaminants. Objective: To value the presence of physical contaminants, such as microplastics in salt intended for human consumption. Method: A quantity of 8 salt samples was acquired in supermarkets in the city of Rio de Janeiro in 2019 and analyzed after dilution in water, according to the coefficient of salt dilution (36g/100mL), heated in plate at 100°C and filtered in filter 0.22μm. Detection was performed with the aid of stereoscope microscope and confirmation was performed under a scanning electron microscope (SEM). Results and Discussion: In 5 samples, the presence of physical contaminants was observed, which due to visual characteristics suggest to be microplastics. The possible presence of microplastics in salt samples is related to contamination of the oceans by microplastics. With this, it is observed the importance of monitoring the quality of human consumption, since it is a by-product of the oceans. Conclusion: Studies in Brazil regarding microplastic contamination is very focused on marine matrices, but it is necessary to think about the study and development of analytical methodologies for detection and identification of these contaminants in food, especially in products of marine origin