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This study developed an experimental flowable composite incorporated with niobium pentoxide (Nb2O5) combined or not with titanium dioxide co-doped with fluorine and nitrogen (NF_TiO2) and evaluated the mechanical and antibacterial properties. The experimental flowable composite (TEGDMA + BisGMA 1:1 + 60%wt - inorganic filler - borosilicate 0.7 µm) was formulated according to the type and concentration of Nb2O5 and NF_TiO2 (0.5, 1, 1.5 and 2 wt%) or NF_TiO2 + Nb2O5 (0.25, 0.5, 0.75 and 1 wt% - 1:1). The control groups were formed by the experimental composite without the incorporation of Nb2O5 and/or NF_TiO2 (GC-E) and by a commercial flowable composite (GC). The characterization of the surface of the composite and its particles was carried out using scanning electron microscopy (SEM) and energy dispersive x-rays (EDX). Specimens were manufactured and subjected to mechanical tests of flexural strength (FS) (n = 12), flexural modulus (FM) (n = 12), roughness (Ra) (n = 10), microhardness (n = 10), and contact angle (n = 10); and, to evaluate the antibacterial activity, they were submitted to tests of biofilm formation against S. mutans (CFU/mL) (n = 5), biofilm biomass by dry weight (n = 5) and confocal laser microscopy (%LIVE/DEAD) (n = 5). Data were submitted to one-way ANOVA and Tukey's post-hoc and, those that were not homoscedastic, but with normality, were submitted to Welch's ANOVA and Games-Howell's post-hoc. Dunnet's test was used to compare the controls with the other experimental groups (α = 5). The Nb2O5 particles had an average size of 32.4 µm and the nanoparticles (NPs) of NF_TiO2, 10 nm. EDX analysis identified isolated peaks of N, F, Ti, and Nb confirming the presence of these particles in the resin matrix. The 1.5% NF_TiO2 group had a higher FS and FM than the controls (p < 0.05). GC showed higher microhardness between groups (p < 0.05). There was no difference between the experimental groups regarding contact angle and roughness (p > 0.05), except for GC, which had the highest Ra values and the lowest contact angle between groups (p < 0.05). Composites containing 0.5%, 1%, 1.5%, and 2% Nb2O5, 1%, 1.5%, and 2% NF_TiO2 and 2% Nb2O5 + NF_TiO2 showed lower biofilm formation (p < 0.05), lower total biofilm biomass (p < 0.05), and a higher percentage of dead cells (44%, 52%, 52%, 79%, 42% 43%, 62%, 65%, respectively) than GC and GC-E (5% and 1%, respectively). It is concluded that the incorporation of 1.5% NF_TiO2 promoted a greater FS and FM among the experimental composites and that the addition of Nb2O5 particles (0.5%, 1%, 1.5%, and 2%), NF_TiO2 (1%, 1.5% and 2%) and the combination Nb2O5 + NF_TiO2 (2%) showed significant antibacterial effects.
Assuntos
Nanopartículas , Nióbio , Teste de Materiais , Resinas Compostas , Antibacterianos/farmacologia , Propriedades de SuperfícieRESUMO
ABSTRACT The COVID-19 has challenged the professions and Implantology also has its challenges in the pandemic. Several factors can interfere with the osseointegration process and more associated factors, greater the interference risks. Risk assessment in the therapy indication is the main decision to define the best technique, the best biomaterial, the best surgical access and the best moment to intervene. The purpose of this review was to investigate and synthesize the scientific evidence on the factors that may interfere with dental implant therapy in the midst of pandemic. The literature was reviewed in databases such as PubMed, Web of Science, Sciello and Google Scholar using the keywords "COVID-19", "pandemic", "risk factors", "impact factor", "dental implants", "dentistry", "oral health", "osseointegration", "bone metabolism", "drug risk factors", "chronic stress", "antidepressants", "zinc", "hydroxychloroquine", "ivermectin", "vitamins", "corticosteroids", "surgical risks" and "disinfection". The present review showed that chronic stress and depression caused by the pandemic, the consequent use of antidepressants, the use of prophylactic and therapeutic drugs such zinc, vitamin D, hydroxychloroquine and corticosteroids, can interfere with bone metabolism and consequently in osseointegration establishment and/or maintenance. Any osseointegrable biomaterial can be influenced by systemic factors and drugs' actions that can affect the homeostasis of the inflammatory process, cell proliferation and bone remodeling. These factors' influence on dental implant therapy should be investigated through new reviews, observational studies and randomized clinical trial.
RESUMO A COVID-19 desafiou as profissões e a Implantodontia também tem seus desafios na pandemia. Vários fatores podem interferir no processo de osseointegração e quanto mais fatores associados, maiores os riscos de interferência. A avaliação do risco na indicação da terapia é a principal decisão para definir a melhor técnica, o melhor biomaterial, o melhor acesso cirúrgico e o melhor momento para intervenção. O objetivo desta revisão foi investigar e sintetizar as evidências científicas sobre os fatores que podem interferir na terapia com implantes bucais em meio a uma pandemia. A literatura foi revisada em bancos de dados como PubMed, Web of Science, Sciello e Google Scholar usando as palavras-chave "COVID-19", "pandemia", "fatores de risco", "fator de impacto", "implantes dentários", "odontologia", "saúde bucal", "osseointegração", "metabolismo ósseo", "fatores de risco medicamentosos", "estresse crônico", "antidepressivos", "zinco", "hidroxicloroquina", "ivermectina", "vitaminas", "corticosteróides", "riscos cirúrgicos" e "desinfecção". A presente revisão mostrou que o estresse crônico e a depressão causados pela pandemia, o consequente uso de antidepressivos, o uso de drogas profiláticas e terapêuticas como zinco, vitamina D, hidroxicloroquina e corticosteroides, podem interferir no metabolismo ósseo e consequentemente no estabelecimento da osseointegração e/ou sua manutenção. Qualquer biomaterial osseointegrável pode ser influenciado por fatores sistêmicos e ações de drogas que podem afetar a homeostase do processo inflamatório, proliferação celular e remodelação óssea. A influência desses fatores na terapia com implantes dentários deve ser investigada por meio de novas revisões, estudos observacionais e ensaios clínicos randomizados.
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Objective: To describe the recommendations, physical characteristics, methods of disinfection and the effectiveness of using homemade masks in reducing the transmission of COVID-19. Methods: Search was performed in the MEDLINE, SciELO and Google Scholar databases, in addition to the official recommendations for use. Results: 31 references were included. The filtration capacity of tissues varied between 5 and 98%. 100% cotton fabrics in two or three layers showed filtration efficiency between 70 and 99%, in vitro. Homemade masks, surgical and respirators showed breathability between 2.2 to 3.0 Pascal. The ability to reduce the spread of microorganisms by people wearing home masks was three times less than when using surgical masks, but it was superior to not wearing masks. Conclusion: The breathability of homemade masks may be adequate, while the filtration efficiency seems to be inferior to surgical masks, but superior to no mask use. There is no evidence to support the efficacy and effectiveness of homemade masks.
Objetivo: Descrever as recomendações, características físicas, métodos de desinfecção e eficácia de uso de máscaras caseiras na redução da transmissão da COVID-19. Métodos: Realizou-se busca nas bases de dados MEDLINE, SciELO e Google Scholar, além das recomendações oficiais de uso. Resultados: Foram incluídas 31 referências. A capacidade de filtração de tecidos variou entre 5 e 98%. Tecidos 100% algodão em duas ou três camadas apresentaram eficácia de filtração entre 70 e 99% em estudos in vitro. Máscaras caseiras, cirúrgicas e respiradores apresentaram respirabilidade entre 2,2 e 3,0 Pascal. A capacidade de redução da propagação de microrganismos por pessoas usando máscaras caseiras foi três vezes menor do que ao usar máscaras cirúrgicas, embora tenha sido superior ao não uso de máscaras. Conclusão: A respirabilidade de máscaras caseiras mostrou-se adequada, enquanto a eficácia de filtração parece ser inferior à das máscaras cirúrgicas, mas superior a não usar máscara. Não há evidências que respaldem a eficácia e efetividade das máscaras caseiras.
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Objetivo: Descrever as recomendações, características físicas, métodos de desinfecção e eficácia de uso de máscaras caseiras na redução da transmissão da COVID-19. Métodos: Realizou-se busca nas bases de dados MEDLINE, SciELO e Google Scholar, além das recomendações oficiais de uso. Resultados: Foram incluídas 31 referências. A capacidade de filtração de tecidos variou entre 5% e 98%. Tecidos 100% algodão em duas ou três camadas apresentaram eficácia de filtração entre 70% e 99% em estudos in vitro. Máscaras caseiras, cirúrgicas e respiradores apresentaram respirabilidade entre 2,2 e 3,0 Pascal. A capacidade de redução da propagação de microrganismos por pessoas usando máscaras caseiras foi três vezes menor do que usando máscaras cirúrgicas, embora tenha sido superior ao não uso de máscaras. Conclusão: A respirabilidade de máscaras caseiras mostrou-se adequada, enquanto a capacidade de filtração parece ser inferior à das máscaras cirúrgicas, mas superior a não se usar máscara. Não há evidências que respaldem a eficácia e efetividade das máscaras caseiras.
Objetivo: Describir las recomendaciones, características físicas, métodos de desinfección y efectividad de mascarillas caseras para reducir la transmisión de COVID-19. Métodos: La búsqueda se realizó en las bases de datos MEDLINE, SciELO y Google Scholar, además de las recomendaciones oficiales de uso. Resultados: Se incluyeron 31 referencias. La capacidad de filtración de los tejidos varió entre 5% y 98%. Los tejidos al 100% de algodón, en dos o tres capas, mostraron eficiencia de filtración entre 70% y 99%, en estudios in vitro. Mascarillas caseras, quirúrgicas y de respiradores mostraron respirabilidad entre 2,2 y 3,0 Pascal. La capacidad de reducir la propagación de microorganismos por personas que usan máscarillas caseras fue tres veces menor que cuando usaban mascarillas quirúrgicas, pero superior a no usarlas. Conclusión: La respirabilidad de las mascarillas caseras puede ser adecuada, mientras que la eficiencia de filtración parece ser inferior a la de las mascarillas quirúrgicas, pero superior a no utilizar mascarilla. No hay evidencia que respalde su eficacia y efectividad.
Objective: To describe the recommendations, physical characteristics, disinfection methods and efficacy of the use of homemade face masks to reduce COVID-19 transmission. Methods: We searched MEDLINE, SciELO, and Google Scholar, in addition to the official recommendations for the use of masks. Results: Thirty-one references were included. Fabric filtration efficiency ranged from 5% to 98%. The filtration efficacy of three layered 100% cotton fabric face masks ranged from 70% and 99% in vitro studies. Homemade, surgical, and respirator masks showed breathability between 2.2 and 3.0 Pascal. The capacity to reduce the spread of microorganisms by people wearing homemade face masks was three times lower when compared to those wearing surgical masks, although this capacity was higher when compared to those who did not wear masks. Conclusion: The breathability of homemade masks proved to be adequate, while the filtration ability seemed to be lower than that of surgical masks, but it was better than not wearing any masks at all. There is no evidence to support the efficacy and effectiveness of homemade masks.