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HA001 - Hatton
Área: 3 - Controle de infecção / Microbiologia / Imunologia

Apresentação: 10/09 - Horário: 08h00 às 11h30 - Sala: Hall Seringueira

Targeted salivary peptides strategies against SARS-CoV-2 cell entry: a molecular docking driven screening and in vitro study
Garcia-Junior MA, Grosche VR, Palmeira LS, Teles CM, Bergamini FRG, Andrade BS, Jardim ACG, Sabino-Silva R
Conflito de interesse: Autodeclarado "Existe expectativa de criação de patente"

COVID-19 is related to ~500 million infections and ~6 million deaths worldwide. The receptor-binding domain (RBD) motif of Spike protein in SARS-CoV-2 interacts with angiotensin-converting enzyme 2 (ACE2) for viral entry and subsequent replication. Although saliva contains antiviral components, SARS-CoV-2 infection was confirmed in mucosae of oral cavity. We hypothesize that salivary peptides can interact with RBD in SARS-CoV-2 to prevent viral entry into host cells. Thus, the aim was to select salivary peptides driven to SARS-CoV-2 and to determine their antiviral activity to block viral entry. Based on 2193 salivary peptides sequences, we modeled a pipeline with 298 salivary peptides using BLASTp from Protein Data Bank and performed an in silico bioinformatic molecular docking against RBD-Spike using Hpepdock Server. The 4 salivary peptides with higher interaction on SARS-CoV-2 (-227 to -209 Kcal/Mol) were synthesized to assess blocking viral entry using in vitro VSV-eGFP-SARS-CoV-2 infected VERO cells. The salivary peptides Spep5, Spep4, Spep9, and Spep2 at 50ug/mL inhibit in vitro infection rates at 44%, 50%, 38%, and 68%, respectively, with cell viability of ~100%. The Spike-salivary peptides interaction blocked Spike/ACE2 docking and these effects were maintained (-12% to 16%) to Gamma, Delta, and Omicron variants.

Altogether, the application of naturally occurring salivary peptides Spep5, Spep4, Spep9, and Spep2 in oral antiviral delivery systems represents a potential alternative for preventing SARS-CoV-2 infection in COVID-19.

(Apoio: FAPs - FAPEMIG  N° APQ-02148-21  |  CAPES  N° 23038.003950/2020-16)
HA002 - Hatton
Área: 5 - Materiais Dentários

Apresentação: 10/09 - Horário: 08h00 às 11h30 - Sala: Hall Seringueira

Evaluation of flexural strength, antimicrobial activity and characterization of acrylic resins incorporated with α-Ag2WO4 and β-AgVO3
Ferreira I, Sahm BD, Teixeira ABV, Castro DT, Assis M, Longo E, Reis AC
Conflito de interesse: Não há conflito de interesse

The objective was to evaluate the flexural strength, antimicrobial activity and surface characterization of self-cured and heat-cured resins incorporated with silver tungstate (α-Ag2WO4) and silver vanadate (β-AgVO3) at 0%, 0.5%, 1% and 3% concentrations. The nanomaterials were added to the resin powder to make the specimens: 65 x 10 x 3.3 mm for flexural strength, 6 x 10 mm for antimicrobial activity and 9x2 mm for SEM and EDS. The flexural strength (n=10) was evaluated with 20 Kgf/5 mm/min load. S. mutans and C. albicans biofilms (n=8) were formed for 48h on the specimens and CFU/mL was counted. SEM and EDS (n=1) were performed. ANOVA and bonferroni were applied (p>0.05). For flexural strength, self-cured resin showed no difference between groups with incorporation of the nanomaterials (p>0.05) and the heat-cured showed reduced flexural strength in the 3% α-Ag2WO4 and 1% and 3% β-AgVO3 groups. For CFU, the incorporation of α-Ag2WO4 did not show efficacy for both resins, and for β-AgVO3 the 3% group promoted reduction of CFU of S. mutans for both resins. For C. albicans the self-cured resin 3% showed reduction of CFU. The EDS analysis demonstrated the presence of the chemical elements of the nanomaterials and by SEM it was observed that the incorporation of β-AgVO3 in the heat-cured resin promoted greater irregularity and pores on the surface.

It was concluded that the incorporation of nanomaterials promoted reduction of flexural strength for the heat-cured resin and the incorporation of β-AgVO3 promoted antimicrobial activity, however more irregularity on the surface.

(Apoio: FAPESP  N° 2021/02306-6)
HA003 - Hatton
Área: 5 - Materiais Dentários

Apresentação: 10/09 - Horário: 08h00 às 11h30 - Sala: Hall Seringueira

Physical, chemical, mechanical, and microbiological properties of TNZT and Ti-6Al-4V obtained by machining and additive manufacturing
Tardelli JDC, Valente MLC, Otani LB, Alves F, Gargarella P, Bagnato VS, Bolfarini C, Reis AC
Conflito de interesse: Não há conflito de interesse

The objective was to compare the physical, chemical, mechanical, and microbiological properties between disks (n=10) of Ti-6Al-4V and Ti-35Nb-7Zr-5Ta (TNZT) obtained by Machining (M) and additive manufacturing (AM) by Selective Laser Melting technique. The disks were analyzed by scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX), x-ray diffraction (XRD), wettability, surface free energy, roughness by confocal laser microscopy, Vickers microhardness (VM), and colony-forming units (CFU) against S. aureus. Two-way ANOVA (p<0.05) was applied. Greater roughness and irregularity were observed in the AM discs. The chemical composition of the alloys by EDX was compatible with the expected concentrations. For TNZT, the manufacturing technique interfered in the phases according to the XRD. The wettability and surface free energy of TNZT was higher than Ti-6Al-4V and for the manufacturing techniques, there was no significant difference. Ti-6Al-4V showed higher hardness than TNZT and the M technique was higher than AM. There was no difference in S. aureus CFU between the groups.

It was concluded that the AM technique generated more irregular and rough surfaces, and lower hardness, without significant changes in relation to M in terms of chemical composition, wettability, surface free energy, and bacterial formation. The TNZT alloy showed higher hydrophilicity, surface free energy, and roughness, lower hardness, manufacturing techniques interfered in its phases, and no differences for CFU compared to Ti-6Al-4V.

(Apoio: FAPs - Fapesp  N° 2020/05272-2)
HA004 - Hatton
Área: 7 - Patologia Oral

Apresentação: 10/09 - Horário: 08h00 às 11h30 - Sala: Hall Seringueira

Treatment effectiveness and systemic toxicity of a tissue conditioner modified with antifungals in a rat model of denture stomatitis
Moraes GS, Albach T, Sugio CYC, Cachoeira VS, Kiratcz F, Santos FA, Neppelenbroek KH, Urban VM
Conflito de interesse: Autodeclarado "As autoras Urban VM e Neppelenbroek KH são responsáveis pelo pedido de patente BR 10 2019 007452 3, que abrange a obtenção dos complexos de inclusão com β-ciclodextrina discutidos neste trabalho."

This study assessed the treatment effectiveness and systemic toxicity of a tissue conditioner modified with antifungals in a rat model of denture stomatitis. Healthy Wistar rats were randomly assigned to the groups: NC (negative control), SD (sterile device), DS (denture stomatitis), Soft (Softone), Nys (nystatin), Nys:βCD (nystatin:β-cyclodextrin), Chx (chlorhexidine), or Chx:βCD (chlorhexidine:β-cyclodextrin). Rats of all groups, except NC and SD, wore a palatal device contaminated with Candida albicans to develop denture stomatitis. Then, rats from the Soft, Nys, Nys:βCD, Chx, and Chx:βCD groups had their devices relined with a tissue conditioner modified (or not) with antifungals at their minimum inhibitory concentrations against C. albicans. After four days, treatment effectiveness was assessed by visual analysis, CFU/mL count, histological analysis, and through myeloperoxidase (MPO) and N-acetylglucosaminidase (NAG) assays. The rats also had their blood collected for biochemical analyses and had their liver, lungs, stomach, and kidneys removed for histopathological, MPO and NAG analyses. Groups Soft, Nys, Nys:βCD, and Chx presented a significant decrease in CFU values in comparison to the DS group. All experimental groups showed lower MPO and NAG activity in the palate compared to the DS group. No relevant renal, gastric, nor pulmonary changes were noticed. The Chx group presented a significantly higher MPO activity in the liver.

These findings suggest that this modified material could be a viable and safe treatment for denture stomatitis.

(Apoio: CAPES  N° 001)
HA005 - Hatton
Área: 8 - Periodontia

Apresentação: 10/09 - Horário: 08h00 às 11h30 - Sala: Hall Seringueira

PM2.5 air pollution exposure intensifies periodontal disease
Pelegrin AF, Carvalho JS, Spolidorio LC
Conflito de interesse: Não há conflito de interesse

Air pollution is a modifiable risk factor for several diseases, although uncertainties remain about fine particulate matter (PM2.5) effects on health. There are no scientific reports that describe its effects in mouth, especially in periodontium and periodontitis occurrence. We investigated the relationship of ambient PM exposure (APM) with periodontal homeostasis alteration and immunoinflammatory periodontal disease. Forty mice were divided in 4 groups, allowing the evaluation of periodontal conditions on filtered or APM exposure. To evaluate APM impact on periodontium, histopathological analysis, quantification of cytokines, and evaluation of oxidative stress process were performed from maxillae samples, involving first upper molars region. Compared with filtered air groups, APM increased reactive oxygen species generation, and decreased antioxidant enzymes activity, provoking oxidative stress. APM also affected periodontal disease progression, potentiating the expression of genes associated with inflammation and bone loss, such as interleukin-1 beta and tumor necrosis factor alpha. Moreover, APM significantly increased mast cells recruitment and histamine production, demonstrating air pollution had malefic effects on experimental periodontitis, stimulating inflammation by unbalanced oxidative stress response and impaired alveolar bone metabolism.

The immune system, inflammation and alveolar bone loss are related to each other. APM altered immune response, triggering inflammatory process, and potentiated tissues damage.

(Apoio: FAPESP  N° 2019/27272-7)
HA006 - Hatton
Área: 9 - Ciências do comportamento / Saúde Coletiva

Apresentação: 10/09 - Horário: 08h00 às 11h30 - Sala: Hall Seringueira

The alcohol harm paradox and tooth loss
Oliveira LM, Pelissari TR
Conflito de interesse: Não há conflito de interesse

Evidence consistently finds that people with lower socioeconomic position are disproportionately or disparately affected by alcohol-related harms compared with advantaged groups, despite reporting similar or even lower average levels of consumption, and this relationship was named alcohol harm paradox (AHP). This study aimed to investigate the occurrence of the AHP associated to tooth loss in adults from a population-based sample. A total of 60,271 non-institutionalized adults (30 years or more) were evaluated using data from the 2019 Brazilian National Health Survey. Alcohol consumption, dichotomized as current heavy drinkers (according to NIAA thresholds) or not, and tooth loss, expressed as both numerical value and lack of functional dentition, were assessed using self-reported data. Covariates included educational attainment and household income. The occurrence of AHP was estimated using the two inferential approaches: effect modification analysis (including income and education as effect modifiers) in negative binomial regression models and marginal structural modeling (including alcohol consumption as a mediator of the effects of income and education on tooth loss). The association between alcohol consumption and tooth loss was stronger among those with lower income and education, but heavy drinking explained little the effect of income and education on tooth loss.

We found the occurrence of AHP related to tooth loss using the effect modification hypothesis. However, alcohol consumption seems to explain little tooth loss inequalities.

(Apoio: CNPq  N° 160262/2020-8)
HA007 - Hatton
Área: 10 - Implantodontia básica e biomateriais

Apresentação: 10/09 - Horário: 08h00 às 11h30 - Sala: Hall Seringueira

Pre-clinical behavior of poly(butylene adipate-co-terephthalate) and niobium-containing bioactive glasses barrier membranes
Balbinot GS, Leitune VCB, Soares RMD, Visioli F, Ponzoni D, Collares FM
Departamento de Odontologia Conservadora UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL
Conflito de interesse: Não há conflito de interesse

Bioactive resorbable barrier membranes with tailored physical and biological properties are a demand to facilitate and enhance guided bone regeneration (GBR) allowing successful implant-supported rehabilitation. In the present study, the pre-clinical behavior of a poly(butylene adipate-co-terephthalate)/niobium-containing bioactive glasses (PBAT/BAGNb) barrier membranes was investigated in a critical-size defect model in rat calvaria. Sixty-three male Wistar rats were submitted to a GBR procedure where membranes were applied in 5mm calvaria defect according to the groups: (1) BAGNb: PBAT/BAGNb membranes; (2) PBAT: PBAT membranes and (3) SHAM: empty defect. A follow-up of 7, 15, and 30 days was established and calvaria tissue was analyzed by x-ray computed microtomography and hematoxylin and eosin histological analysis. BAGNb group presented an enhanced percentage of new bone at 30 days (36.59%) when compared to PBAT (25.46%) and SHAM (25.08%) (p< 0.05). A reduction in the trabecular separation and increase in trabecular number were observed for BAGNb at 30 days as well. The formation of new bone in histological sections was increased for BAGNb group, with enhanced tissue maturation over time.

The controlled properties in PBAT/BAGNb membranes promoted an enhanced mineral formation and a more organized trabecular structure in the early stages of bone regeneration, showing a reliable behavior of developed materials for GBR procedures.

(Apoio: Fundo de Incentivo à Pesquisa e Eventos do Hospital de Clínicas FIPE-HCPA  N° 2020-0075)
HA008 - Hatton
Área: 10 - Implantodontia básica e biomateriais

Apresentação: 10/09 - Horário: 08h00 às 11h30 - Sala: Hall Seringueira

Transcriptomic and ontological profile triggered by anti-fibronectin aptamers on 3D scaffolds in osteoimmunology
Costa NMM, Parisi L, Ghezzi B, Martínez CJH, Messora MR, Oliveira PT, Macaluso GM, Palioto DB
Conflito de interesse: Não há conflito de interesse

The adsorption of bioactive molecules on three-dimensional scaffolds (SCA) surface possibly optimizes the initial events associated with bone regeneration. Here, the effect of SCA functionalization by anti-fibronectin aptamers (APT) on osteogenesis was verified in in vitro (UMR-106 lineage) and in vivo (calvaria rats defect) investigations. The in vitro assay evidenced more mineralized matrix formation and IBSP labeling in the SCA+APT+OSB group at 10 days. For the in vivo experiment, the analyses were performed in SCA and SCA+APT groups at 5 and 15 days. The Micro-CT revealed greater bone volume and less bone porosity at 5 days in SCA+APT group. Mason's stain and immunofluorescence assay presented more collagen tissue, some bone formation points and high ALP staining in the APT group at 5 days. The transcriptomic investigation demonstrated more differentially expressed genes between SCA and SCA+APT groups at 15 days. At 5 days, the gene ontology (GO) assessment represented differences in cell adhesion and cell membrane ion channels functions (both up-regulated). At 15 days, these differences were associated with immune response, extracellular matrix components, antioxidant activity (up-regulated) and cellular cytoskeleton polymerization (down-regulated). The functions validation was performed by RT-PCR verifying VIM, HPRT1, CLCN4, CD24, KRTAP7-1, PSME2, TNF and IL-1β gene expression.

These evidences showed that the SCA functionalization with APT provided an improvement in osteoblastic differentiation and in osteoimmunology.

(Apoio: FAPESP  N° 2018/12036-3)
PN0001 - Painel Aspirante
Área: 2 - Terapia endodôntica

Apresentação: 08/09 - Horário: 08h00 às 11h30 - Sala: Área dos Painéis

Avaliação in vitro da ação antimicrobiana de cinco cimentos endodônticos
Cavalcante JT, Bueno CES, De Martin AS, Fontana CE, Pelegrine RA, Pinheiro SL, Rocha DGP
Conflito de interesse: Não há conflito de interesse

O presente estudo teve o objetivo de avaliar in vitro a eficácia de diferentes cimentos endodônticos, quanto as ações antimicrobianas, frente a um biofilme monocrobiano de Enteroccocus Faecalis (E.A). Os cimentos foram divididos em cinco grupos; Grupo Ah Plus JET(GAHJ), Grupo Endomethasone (GEM), Grupo Bio C Sealer (GBCS), Grupo Sealer Plus (GSP) e Grupo BioRoot RCS (GBRRCS). O teste do método em difusão em ágar foi utilizado. Placas de petri contendo o meio Brain Heart Ifunsion (BHI) ágar foram inoculadas com 0,1 ml de de cultura de E.A(Enteroccoccus Faecalis)testada por meio de swabs estéreis, esfregados por toda a superfície do meio. Em sequência, as placas foram incubadas a 37C por 7 dias em aerobiose. Durante esse período, os diâmetros dos halos de inibição de crescimento bacteriano ao redor dos furos foram mensurados nos períodos de 24h, 48h e 168h (7 dias). O teste Tukey ao nível de 5% foi utilizado. Usando a analise de variância (ANOVA) para os cimentos testados , verificou-se que houve uma diferença significativa entre as médias dos cimentos.O maior efeito inibitório ocorreu com o grupo GEM com diferenças estatisticamente significantes em relação aos outros grupos amostrais após 24, 48 horas e 7 dias.

Concluiu-se que os cimento Endomethasone e AHPlus Jet obtiveram maior efeito antimicrobiano em um período de 7 dias. Os cimentos BioRoot, Bio C sealer e Sealer Plus não apresentaram efeito antimicrobiano no mesmo período estudado.

PN0002 - Painel Aspirante
Área: 2 - Biologia pulpar

Apresentação: 08/09 - Horário: 08h00 às 11h30 - Sala: Área dos Painéis

Avaliação da regeneração do complexo dentino-pulpar em dentes de ratos após transplante de células-tronco de dentes decíduos humanos
Santos LRK, Bueno CES, Pelegrine AA, Martinez EF, Stringheta CP, Pelegrine RA
Conflito de interesse: Não há conflito de interesse

O objetivo do presente estudo foi avaliar a capacidade regenerativa do complexo dentino-pulpar em molares de ratos adultos após pulpectomia e transplante de células-tronco da polpa dentária de dentes decíduos humanos. Canais mesiovestibulares dos primeiros molares superiores de 12 ratos foram distribuídos em dois grupos: CT, dentes do lado esquerdo cujos canais receberam transplante de células-tronco veiculadas em tampão fosfato-salino (PBS); PBS, dentes homólogos do lado direito cujos canais receberam apenas PBS. Após pulpectomia e preparo dos canais, os dentes receberam os transplantes. Os animais foram eutanasiados e os espécimes submetidos a avaliação histológica e imunohistoquímica. Os dados foram analisados quanto à presença ou ausência de tecido conjuntivo, células morfologicamente semelhantes a odontoblastos, tecido mineralizado e infiltrado inflamatório. No grupo PBS, a análise histológica revelou a presença de substância amorfa e remanescentes de tecido mineral ao longo do canal e presença abundante de células inflamatórias na região periapical. No grupo CT, observou-se substância amorfa e remanescentes de tecido mineral ao longo do canal, além de células morfologicamente semelhantes a odontoblastos e plugue mineral na região apical do canal. A região periapical deste grupo mostrou leve infiltrado inflamatório, intensa vascularização e neoformação de tecido conjuntivo organizado.

Concluiu-se que, os achados histológicos e imunohistoquímicos indicaram potencial de neoformação tecidual após o procedimento de transplante de células-tronco.