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This study aimed to compare the metabolic profile of unstimulated (US) and stimulated (SS) saliva samples from pregnant women with/without obesity and periodontitis. Ninety-six pregnant women were divided into: obesity + periodontitis (OP = 20); obesity/no periodontitis (OWP = 27); normal BMI + periodontitis (NP = 20); and normal BMI/no periodontitis (NWP = 29). US and SS samples were collected by expectoration and chewing of sterilized parafilm gum, respectively, and samples were individually analyzed by Proton Nuclear Magnetic Resonance (1H-NMR). Univariate (t test and correlations) and multivariate (Principal Component Analysis–PCA, and Partial Least Square–Discriminant Analysis—PLS-DA with Variance Importance Projection–VIP scores) and Metabolite Set Enrichment Analysis were done (p < 0.05). Metabolites commonly found in all groups in elevated concentration in US samples were 5-Aminopentoate, Acetic acid, Butyric acid, Propionic acid, Pyruvic acid, and Succinic acid. They were mainly related to the butyrate metabolism, citric acid cycle, amino sugar metabolism, fatty acids biosynthesis, pyruvate metabolism, glutamate metabolism, and Warburg effect. Metabolites commonly found in all groups that were in elevated concentration in SS samples were Citrulline, Fumaric acid, Histidine, N-acetyl glutamine, N-acetylneuraminic acid, para-hydroxyphenylacetic acid, Proline, Tyrosine. Although some differences were found between unstimulated and stimulated saliva samples from pregnant women with/without obesity and periodontitis, stimulated saliva collection seems adequate, demonstrating similar metabolic pathways to unstimulated saliva samples when groups are compared.

The aim was to discuss the indications, contraindications, advantages, and disadvantages of Nonmetal clasp dentures (NMCDs), as well as the most relevant properties of its constituent materials. A search was conducted using the keywords: “nonmetal clasp dentures,” “thermoplastic resin,” “flexible resin removable partial denture,” “polyamide,” and “nylon” in databases PubMed/Medline, Lilacs, SciELO, and textbooks between 1955 and 2020. Theses and texts without reliable sources of publication were excluded. Once the analysis instruments were determined, the data were analyzed and discussed. NMCDs present high flexibility, easy adaptation to the abutments, color compatibility and biocompatibility with the oral mucosa, and absence of visible metal clasps. However, they need laboratory relining, grinding, and polishing, do not have criteria for its planning, become rougher and stained over time, and are able to traumatize supporting tissues. The association with metal components seems to be an alternative to increase the success of NMCDs by combining esthetics and biomechanical principles of conventional removable partial dentures. The lack of long-term clinical studies makes the professionals to rely solely on previous experiences or on the manufacturers' recommendations. It suggested that NMCDs must be indicated with caution when not used temporarily.

New glass ceramics enriched by polycrystalline materials has been produced by different processing methods. However, for these materials to be used as restorative dental materials in esthetical areas they must count with good optical properties, which are directly influenced by their structure and chemical composition. For these reasons, the aim of this study was to produce a new glass ceramic containing SiO2+Y-TZP via uniaxial/isostatic powder compression and to structurally and chemically characterize this material relating to its optical properties. SiO2 and Zpex® were used as starting powders. These two powders were mixed (97w%-3% ratio) and pressed in uniaxial (80MPa) and isostatic (206MPa) press and sintered at 1150ºC for 2h. The starting powders, the mixed powder (before sintering) and the sintered specimens were submitted to Scanning Electron Microscope/Energy Dispersive X-ray Spectroscopy (SEM/EDX), Transmission Electron Microscope (TEM), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The materials density was measured. The contrast ratio and translucency parameter of the sintered specimen were compared to lithium disilicate (IPS e.max® CAD HT A1) and zirconia-reinforced lithium silicate (Celtra Duo® HT A1), using Kruskal-Wallis and post-hoc Dunn tests with a significance level set at 5%. Agglomerations of SiO2 and Zpex could be seen under SEM/EDX analysis due to their reduced particle size, yet, when sintered, some remaining porosities could be seen. The TEM analysis evidenced the spherical character of SiO2 grains and the crystallographic pattern of the Zpex particles. When mixed, Zpex can be seen inside the grain of SiO2. XDR analysis pointed out that SiO2 was amorphous, and Zpex presented monoclinic (m) and tetragonal (t) peaks. After sintering, crystallization of SiO2 can be seen without new m peaks. The FTIR spectra bands suggested an interaction between Si, O and Zr. The theoretical density value of the experimental ceramics was 1.663 g/cm3. The contrast ratio and the translucency parameter of the experimental ceramic were higher (p=0,000001) and lower (p=0,000001), respectively, than those of lithium disilicate and zirconia-reinforced lithium silicate. It can be concluded that the uniaxial/isostatic powder compression is an efficient method to obtain experimental ceramics for dental purposes and 1150ºC for 2h is sufficient to crystallize SiO2 without inducing t-m transformation of zirconia. Yet, this sintering protocol seems to be insufficient to densify the experimental ceramic, which may the reason for its lack of translucency. Novas cerâmicas vítreas enriquecidas por materiais policristalinos tem sido produzidas por diferentes métodos de processamento. Entretanto, para que sejam utilizados como materiais restauradores odontológicos em áreas estéticas, eles devem apresentar boas propriedades ópticas, que estão diretamente influenciadas por sua estrutura e composição química. Por esses motivos, o objetivo deste estudo foi produzir uma nova cerâmica vítrea contendo SiO2+Y-TZP através da via uniaxial/isostática, e caracterizar este material estrutural e quimicamente, relacionando às suas propriedades ópticas. SiO2 e Zpex® foram usados como pós de partida, misturados (97m%-3m%), prensados em prensa uniaxial (80MPa) e isostática (206MPa) e sinterizados à 1150ºC por 2h. Os pós de partida, o pó após a mistura (prévio à sinterização) e a amostra sinterizada foram submetidos à Microscopia Eletrônica de Varredura/Espectroscopia por Energia Dispersiva de Raios-X (MEV-EDX), Microscopia Eletrônica de Transmissão (MET), Difração de Raios-X (DRX) e Espectroscopia de Infravermelho com Transformada de Fourier (FTIR). A densidade do material foi mensurada. A razão de contraste e o parâmetro de translucidez da amostra sinterizada foram comparados aos do dissilicato de lítio (IPS e.max® CAD HT A1) e do silicato de lítio reforçado por zircônia (Celtra Duo® HT A1), utilizando os testes de Kruskal-Wallis e post-hoc Dunn com nível de significância de 5%. Aglomerações SiO2 e Zpex foram vistas sob MEV/EDX devido ao tamanho reduzido das partículas, porém, quando sinterizado, algumas porosidades puderam ser vistas. A análise em MET evidenciou o caráter esférico dos grãos de SiO2 e o padrão cristalográfico das partículas de Zpex. Quando misturados, Zpex pode ser visto dentro de uma partícula de SiO2. A análise em DRX destacou que a SiO2 era amorfo e Zpex apresentava picos monoclínicos (m) e tetragonais (t). Após a sinterização, a cristalização da SiO2 pode ser vista sem a formação de novos picos m. As bandas do espectro do FTIR sugeriram uma interação entre Si, O e Zr. A densidade do material foi 1,663g/cm3. A razão de contraste e o parâmetro de translucidez da cerâmica foi maior (p=0,000001) e menor (p=0,000001), respectivamente, que os do silicato de lítio e do silicato de lítio reforçado por zircônia. Podese concluir que a compressão dos pós em prensa uniaxial/isostática é um método eficiente em produzir cerâmicas experimentais para uso odontológico, e que 1150ºC por 2h é suficiente para cristalizar o SiO2 sem induzir transformação t-m na zirconia. Contudo, esse protocolo de sinterização parece ser insuficiente para densificar a cerâmica experimental, o que pode prejudicar sua translucidez.

Objectives: this study systematically reviewed the literature in order to better understand the association among COVID-19, pregnancy and neonates. Methods: MEDLINE, EMBASE, Web of Science, BVS and SCOPUS were assessed, considering the terms: (covid 19 OR covid-19 OR novel coronavirus OR 2019 novel coronavirus OR 2019-nCoV OR sarscov 2 OR sars-cov-2 OR sarscov2 OR sars cov-2) AND (pregnancy OR pregnant OR pregnant women OR gestation OR gestational) AND (infant OR fetal OR neonatal). Thirty full-text were included (408 pregnant women, 11 non-pregnant women and 279 neonates). Results: fever (45.83%) and cough (31.61%) were the main symptoms of COVID-19 during the pregnancy. Low levels of lymphocytes (32.10%), elevated levels of C-reactive protein (32.35%); leukocytosis (29.41%); neutrophil (5.88%); and radiographic alterations on chest CT, x-ray or ultrasound (45.84%) were the main laboratorial findings. Cesarean delivery and preterm were registered in 239 and 49 cases, respectively. Ten neonates tested positive for SARS-CoV-2. Conclusion: when COVID-19 pneumonia affects women during pregnancy, the symptoms are similar to those experienced by non-pregnant women. In addition, there is still no plausible evidence suggesting vertical transmission of SARS-CoV-2 virus from mother to child.