Chitosan nanoparticles loaded with epigallocatechin-3-gallate: synthesis, characterisation, and effects against Streptococcus mutans biofilmEpigallocatechin-loaded chitosan nanoparticles: effects against Streptococcus mutans biofilm.

This study evaluated the effects of chitosan nanoparticles loaded with epigallocatechin-3-gallate (EGCG) against Streptococcus mutans biofilm. EGCG-loaded chitosan (Nchi + EGCG) nanoparticles and Chitosan (Nchi) nanoparticles were prepared by ion gelation process and characterised regarding particle size, polydispersion index, zeta potential, and accelerated stability. S mutans biofilms were treated twice daily with NaCl 0.9% (negative control), Nchi, Nchi + EGCG, and chlorhexidine (CHX) 0.12% (positive control). After 67 h, the biofilms were evaluated for acidogenesis, bacterial viability and dry weight. Biofilm morphology and structure were analysed by scanning electron microscopy. The nanoformulations presented medium to short-term stability, size of 500 nm, and polydispersion index around 0.400. Treatments affected cell morphology and biofilm structure. However, no effects on microbial viability, biofilm dry weight, and acidogenesis were observed. Thus, the nanoformulations disassembled the biofilm matrix without affecting microbial viability, which makes them promising candidates for the development of dental caries preventive and therapeutic agents.

Effects of the green tea catechin epigallocatechin-3-gallate on Streptococcus mutans planktonic cultures and biofilms: systematic literature review of in vitro studies.

This study aimed at performing a systematic review of the literature on the effects of epigallocatechin-3-gallate (EGCG) on Streptococcus mutans planktonic cultures and biofilms. The selected references demonstrated that EGCG suppresses S. mutans acid production by inhibiting the activity of enzymes such as lactate dehydrogenase and FIF0-ATPase. Regarding virulence factors, one study reported a reduction in soluble and insoluble polysaccharide synthesis, another demonstrated that EGCG inhibited GTase activity, and another showed effects of EGCG on the expression of gtf B, C, and D. The effects of EGCG on S. mutans biofilms were reported only by 2 of the selected studies. Moreover, high variability in effective concentrations and microbial assessment methods were observed. The literature suggests that EGCG has effects against S. mutans planktonic cells viability and virulence factors. However, the literature lacks studies with appropriate biofilm models to evaluate the precise effectiveness of EGCG against S. mutans biofilms.

Conexão SUS: um canal do YouTube como instrumento de formação educacional e fortalecimento do Sistema Único de Saúde / Conexão SUS: a YouTube channel for health education and as tool for the strengthening of the Brazilian Unified National Health System (SUS)

RESUMO Trata-se da análise estatística de alcance e audiência do canal Conexão SUS, através dos dados do YouTube Studio. Foram analisados o alcance do canal e o engajamento do público de 2016 a 2021, avaliando-se o padrão anual de: número de inscritos, visualizações, impressões, compartilhamentos, marcações 'gostei', marcações 'não gostei' e tempo de exibição em horas. A sazonalidade do número de visualizações do canal foi avaliada através de análise do mapa de calor em cluster do número de visualizações diárias do canal de 2016 a 2021. Ademais, foi avaliado o comportamento dos usuários do canal com base nas interações dos usuários com os assuntos abordados pelos vídeos do canal. Assim, foi observado que o canal conta com 19.625 inscritos, 984.347 visualizações, 36.796 horas assistidas e 4.259.577 impressões. A audiência do canal conta com participação de 73,3% de mulheres, com idade entre 25 e 34 anos, que acessam os conteúdos produzidos preferencialmente por dispositivo móvel. Atenção básica é o conteúdo com maior engajamento e alcance do canal. O canal Conexão SUS se mostrou uma ferramenta propulsora da comunicação sobre o Sistema Único de Saúde (SUS) nas redes sociais.

ABSTRACT This manuscript is an analysis of the statistics of the reach and audience of the YouTube Channel Conexão SUS, performed with data provided by the YouTube Studio. Data of audience and engagement of the channel from 2016 to 2021 were studied, evaluating the annual pattern of: number of subscribers, views, impressions, shares, 'like' tags, 'did not like' tags and watched time in hours. The seasonality of the number of channel views was evaluated through cluster heat map analysis of the number of daily views of the channel from 2016 to 2021. In addition, the behavior of the channel's users was evaluated based on the contents covered by the channel's videos, which were categorized into: Primary Health Care, legislation, health system management and health surveillance. Thus, it was observed that the channel accumulates 19.625 subscribers, 984.347 views, 36.796 hours watched and 4.259.577 impressions. The channel's audience includes the participation of 73.3% of women, aged between 25 and 34 years old, who access the content preferably by their mobile device. Primary care is the content with highest engagement and audience of the channel. The Conexão SUS channel proved to be a driving tool for communication about the Unified Health System (SUS) in social networks.

Brazilian dental students and COVID-19: A survey on knowledge and perceptions.

OBJECTIVE: This study evaluated the knowledge and perceptions of Brazilian dental students about COVID-19 and the undergraduate clinical practice during the COVID-19 outbreak by a self-administered Web-based questionnaire. METHODS: A social network campaign on Instagram was raised to approach the target population. The survey covered demographic and academic profile, general knowledge, preventive measures and perception about COVID-19. Descriptive statistics were used to identify frequencies and distributions of variables, which were compared by type of institution and current year of enrolment using the Chi-square or Fisher's exact tests (α = 0.05). RESULTS: A total of 833 valid responses were received over 10 days. Students were able to identify the incubation period, main symptoms and contagious routes of the disease but struggled in recognising the name of the virus responsible for the pandemic. Hand washing before and after a dental appointment with a patient (97.7%) followed by the use of barriers to protect mucosa (97.2%) were the more frequently recognised measures to prevent COVID-19 spread in the dental office. As for the perception of COVID-19, 73.2% of the dental students perceived the disease as severe, whilst only 11.1% of them thought that COVID-19 is severe only for people presenting risk factors. Dental student's knowledge and perception were associated with the type of institution and year of enrolment. CONCLUSION: In summary, the dental students demonstrated an acceptable general knowledge about COVID-19, but dental schools will need to address gaps in knowledge, preventive measures, and perceptions to ensure a safer return to in person activities.

Information sources of Brazilian undergraduate dental students during the COVID-19 outbreak: a cross-sectional study

Aim: This cross-sectional study aimed to investigate where Brazilian dental students seek information about COVID-19 by a self-administered web-based questionnaire. Methods: A social network campaign on Instagram was raised to approach the target population. The dental students responded to a multiple-response question asking where or with whom they get information about COVID-19. The possible answers were government official websites or health and education institutions websites, TV Programs, professors, social media, scientific articles, health professionals, and family members. The data were analyzed by descriptive statistics, and the frequency distributions of responses were evaluated by gender, age, type of institution, and year of enrollment. Results: A total of 833 valid responses were received. The main source of information used by the dental students were government official websites or health and education institutions websites, which were reported by 739 (88.7%) participants. In the sequence, 477 (57.3%) participants chose health professionals while 468 (56.2%) chose scientific articles as information sources. The use of social media was reported by 451 (54.1%) students, while TV programs were information sources used by 332 (39.9%) students. The least used information sources were professors, reported by 317 (38.1%) students, and family members, chosen only by 65 (7.8%) participants. Conclusion: Brazilian dental students rely on multiple information sources to stay informed about COVID-19, mainly focusing their information-seeking behavior on governmental and health professional's websites

Conexão SUS a Youtube channel for health education and as tool for the strengthening of the Brazilian Unified National Health System (SUS)

This manuscript is an analyses of  the statistics of the reach, engagement and audience of the Youtube Channel Conexão SUS performed with data provided by the Youtube Studio. Data of audience and  engagement of the channel  from 2016 to 2021 were studied, evaluating the annual pattern of: number of subscribers, views, impressions, shares, "liked" tags, "did not like" tags and  time watched in hours.  The time series of number of views per day and seasonality of the audience were studied through the heat map of the monthly average of the channel's views. The behavior of channel users was evaluated based on the contents covered by the videos, which were categorized into: primary health care, legislation, health system management and health survaillance. The channel accumulates 19,625 subscribers, 984,347 views, 36,796 hours watched and 4,259,577 impressions. The channel's audience includes the participation of 73.3% of women aged between 25 and 34 years old  who access the channel through their mobile device. There is a pattern of increase followed by a decrease in views that repeats every 180 days.The rise in views is related to the academic year in the first and second semesters of the year. The decrease in views is associated with the months of vacation or school breaks. Primary care is the content with highest engagement and audience of the channel.  The video about the community health agent is the most watched video of this playlist and of the channel (over 7,000 hours watched). The  Conexão SUS channel proved to be a driving tool for communication about the SUS in social networks, which can be used as an instrument for educational training and strengthening of the Brazilian public health system (SUS).

Trata-se da análise estatística de alcance, engajamento e audiência do canal Conexão SUS através dos dados do Youtube Studio. Foram analisados o alcance do canal e engajamento do público de 2016 a 2021, avaliando-se o padrão anual de: número de inscritos, visualizações, impressões, compartilhamentos, marcações "gostei", marcações "não gostei e tempo de exibição em horas. Além disso, estudou-se a série temporal de número de visualização por dia e a sazonalidade na audiência através do mapa de calor da média mensal de visualização do canal. Foi avaliado o comportamento dos usuários do canal com base nos conteúdos abordados pelos vídeos, que foram categorizados em: atenção básica à saúde, legislação, gestão e assistência à saúde. O canal conta com 19.625 inscritos, 984.347 visualizações, 36.796 horas assistidas e 4.259.577 impressões. A audiência do canal conta com a participação de 73,3% de mulheres com idade entre 25 e 34 anos e que acessam os conteúdos produzidos através do dispositivo móvel. Há um padrão de alta seguido de queda de visualizações que se repete a cada 180 dias, sendo a alta relacionada aos períodos letivos no primeiro e segundo semestres do ano e a baixa concentrada nos meses de férias ou recesso escolar. Atenção básica é o conteúdo com maior engajamento e alcance do canal, sendo "agente comunitário de saúde" o vídeo mais assistido (mais de 7 mil horas de exibição).  O canal Conexão SUS se mostrou uma ferramenta propulsora da comunicação sobre o SUS nas redes sociais, que pode ser utilizada como instrumento de formação educacional fortalecimento do sistema.

Comparative Effect of Two Red Lights on Streptococcus mutans Biofilms and Assessment of Temperature Variances in Human Teeth During In Vitro Photodynamic Antimicrobial Chemotherapy.

Objective: The goals of this investigation were to compare the effect of photodynamic antimicrobial chemotherapy (PACT) with two different red lights on in vitro Streptococcus mutans biofilms, as well as to assess the temperature variances caused by PACT on human teeth. Methods: S. mutans biofilms (n = 3) were grown on hydroxyapatite disks, and the antimicrobial effect of PACT was evaluated using toluidine blue O (100 µg/mL) associated with Laserbeam® (LB 56.6 J/cm2) and LumaCare™ (LC -56.6, 158.5, 317.0, and 475.6 J/cm2). Pulpal temperature variances were analyzed using a digital thermocouple placed into the pulp chamber and positioned at the cement-enamel junction level of five teeth samples during irradiation times of 300, 600, and 900 sec for LB, and 22, 60, 120, and 180 sec for LC. The mean average temperature variance was calculated for each group. All data were analyzed through analysis of variance. Results: LB (900 sec) and LC (22 sec) induced similar reductions in the viability of microorganisms. LB did not cause statistically significant increase of temperature, regardless of experimental time, and LC caused temperature increase within the safe spectrum up to 60 sec. Conclusions: PACT seems to be a minimal invasive approach for reducing the viability of cariogenic bacteria. Thus, when applied in vitro for times equal or inferior to 900 and 60 sec for LB and LC, respectively, these light sources might be considered harmless to tooth structures.

Tratamento de extensa lesão de furca associada com canal cavo inter-radicular: relato de caso / Treatment of extensive furcation defect associated with accessory foramina: case report

Introdução: o conhecimento das possíveis variações da cavidade pulpar torna-se necessário para aumentar o êxito nos tratamentos endodônticos, tornando relevante o reconhecimento do canal cavo inter-radicular (CCIR). Objetivo: relatar o caso de um primeiro molar inferior com ampla perda óssea na região de furca associada à presença de canal cavo inter-radicular. Relato de caso: paciente relatou o surgimento de "bolhas ao redor do dente". Ao exame clínico, constatou-se a presença de fístula associada à necrose pulpar do dente #36; não existiam sinais de doença periodontal. Radiograficamente, identificou- se extensa rarefação na região de furca e periapical. Após cuidadoso acesso, foi realizada radiografia na qual constatou-se a presença do FC comunicando a câmara pulpar à furca. Após a localização dos canais radiculares e seu preparo químico-mecânico, procederam-se trocas de hidróxido de cálcio após 240 dias, constatando-se franco reparo. Após 270 dias, obturaram-se os canais radiculares e procedeu-se ao selamento da embocadura desses e do CCIR com MTA. No controle de 360 dias, observou-se a ausência de sinais clínicos indesejáveis e neoformação óssea na região de furca. Conclusão: é de fundamental importância o conhecimento da existência do CCIR e sua relação com lesões de furca em dentes sem sinais clínicos de doença periodontal; nesses casos, a correta sanificação do sistema de canais é capaz de solucionar problemas endoperiodontais, mesmo de grandes proporções, restabelecendo a saúde do paciente e, assim, evitando tratamentos desnecessários.

Effect of Photodynamic Antimicrobial Chemotherapy on Mono- and Multi-Species Cariogenic Biofilms: A Literature Review.

OBJECTIVE: The aim of this literature review is to study the effect of photodynamic antimicrobial chemotherapy (PACT) on mono- and multi-species cariogenic biofilms. METHODS: To this purpose, the database, PubMed, was searched using the descriptors, photodynamic therapy, antimicrobial photodynamic chemotherapy, and photoinactivation, associated with the mandatory presence of the word biofilm. A total of 98 references published from 2003 to 2016 were selected. Moreover, literature reviews (15), investigations that did not have biofilms related to dental caries (65), and those that did not have Streptococcus mutans count as an outcome (7) were excluded, yielding a final amount of 11 publications. RESULTS: The results revealed that Toluidine Blue O was the most used photosensitizer. Among the sources of light, light-emitting diode was the choice, and the biofilm models varied between in vitro and in situ. Multi-species biofilms were more resistant to the antimicrobial effects of PACT due to the thickness and complexity they have, which impede the penetration of the photosensitizer. This fact may also be associated with the type of photosensitizer used as well as with the light exposure time since the antimicrobial effect seems to be dose dependent. Despite this, in all the included publications, the therapy was effective in reducing S. mutans count. CONCLUSIONS: This review demonstrated that under different conditions, PACT is effective in reducing S. mutans count in monospecies biofilms. Multi-species biofilms were more resistant to the antimicrobial action of the therapy, possibly due to their thickness and complexity.

Removal of Separated Endodontic K-File with the Aid of Hypodermic Needle and Cyanoacrylate.

A wide range of accidents might happen during the treatment of the root canal system, where the instrument separation is one of the most unpleasant occurrences. Several techniques have been developed to facilitate the removal of the fragments; however, they generally require specific devices that not always are available to the clinician. The aim of this case report is to present a simple alternative technique to remove from the root canals manual instruments fractured during the treatment. The case has its outline based on a 31-year-old patient who sought the clinic to have her maxillary first left premolar rehabilitated. The clinic and radiographic examinations revealed the need of endodontic retreatment and the presence of a fragment of a K-file instrument localized at the apical third of the palatine canal. The retreatment was initiated by the removal of the obturation materials followed by several unsuccessful attempts to take out the fractured instrument. Hence, it was chosen to perform the fragment removal using a hypodermic needle and cyanoacrylate adhesive. The fragment easily came out, which reinforces the technique adopted as a safe, simple, and low cost mean to solve the problem of fractured instruments using only items already present in the endodontic arsenal.

Inflammatory Cytokines Interleukin-1ß and Tumour Necrosis Factor-α - Novel Biomarkers for the Detection of Periodontal Diseases: a Literature Review.

OBJECTIVES: The article aims to discuss the IL-1ß and TNF-α potential use as salivary biomarkers of periodontal diseases pathogenesis and progression. MATERIAL AND METHODS: This literature review has been registered in PROSPERO database with following number: CRD42016035729. Data investigation was performed on PubMed database as the main source of studies. The following search terms were used: "salivary biomarkers", "periodontal diseases", "TNF-alpha", "Interleukin-1 beta". Clinical trials and animal experimental models of periodontal disease were included in the discussion. In regards to inclusive dates, published studies from January 2006 to December 2015 were considered in this review along with the mentioned inclusion criteria. RESULTS: IL-1ß and TNF-α salivary levels increased in diseased groups, they were associated with onset and disease severity, and their levels reduced in response to periodontal therapy. IL-1ß and TNF-α could be promising biomarkers in the detection of periodontal diseases. CONCLUSIONS: The use of a salivary cytokine-based diagnosis appears to be a screening method capable of diagnosing periodontal diseases in an early fashion, establishing an era of individualized clinical decisions.

Effects of nonsteroidal anti-inflammatory drugs on osseointegration: a review.

The purpose of this study was to review the effects of nonsteroidal anti-inflammatory drugs on osseointegration and determine whether they cause failures in dental implants and whether patients who use them chronically can receive dental implants safely. A bibliographic electronic search was performed using the Cochrane Library, PubMed, and Medline databases, selecting articles published between January 1982 and December 2012. The search included the following keywords, either alone or combined: "nonsteroidal anti-inflammatory drugs," "dental implants," "bone healing," and "osteoprogenitor cells." The inclusion criteria were the following: randomized, double-blind, placebo-controlled clinical studies, in vivo animal model studies of osseointegration, and in vitro studies of the effects of these agents on osteoprogenitor cells. The literature search revealed 360 references. A total of 31 articles met the inclusion criteria, including 2 clinical trials, 20 animal studies, and 9 osteoprogenitor cell studies. The clinical trials revealed that cyclooxygenase-1 (COX-1) inhibitors did not impair osseointegration. The animal studies showed that any drug that is capable of inhibiting COX-2 may impair the osseointegration process. The in vitro studies showed that COX-2 inhibitors are the most potent depressors of osseointegration at the cellular level. Caution must be taken when selecting COX-2 nonsteroidal anti-inflammatory drugs during the postoperative period.