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1.
Clin Oral Investig ; 27(8): 4785-4794, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37391526

RESUMO

OBJECTIVES: To study whether damaged epithelial cells and gingival fibroblast could affect the expression of inflammatory cytokines in healthy cells. MATERIALS AND METHODS: Cell suspensions were submitted to different treatments to obtain the lysates: no treatment (supernatant control), sonication, and freeze/thawing. All treatments were centrifuged, and the supernatants of the lysates were used for experimentation. Cell viability assays, RT-qPCR of IL1, IL6 and IL8, IL6 immunoassay, and immunofluorescence of NF-kB p65 were applied to verify the inflammatory crosstalk of damaged cells over healthy plated cells. Furthermore, titanium discs and collagen membranes were treated with lysates and checked for IL8 expression by RT-qPCR. RESULTS: Lysates obtained upon sonication or freeze/thawing of oral squamous carcinoma cell lines provoked a robust increase in the expression of IL1, IL6, and IL8 by gingival fibroblasts, which was confirmed by IL6 immunoassays. Lysates obtained from the gingival fibroblasts failed to increase the expression of inflammatory cytokines in oral squamous carcinoma cells. Additionally, oral squamous carcinoma cell lysates caused the activation of the NF-kB signalling cascade in gingival fibroblasts as indicated by the phosphorylation and nuclear translocation of p65. Finally, oral squamous carcinoma cell lysates adhered to the titanium and collagen membrane surfaces and increased IL8 expression by gingival fibroblasts growing in these materials. CONCLUSIONS: Injured oral epithelial cells can release factors that incite gingival fibroblasts to become pro-inflammatory. CLINICAL RELEVANCE: Injuries affecting the oral mucosa generate epithelial fragments that may reach the underlying connective tissue and provoke inflammation. These injuries are routinely caused by mastication, sonication for teeth cleaning, teeth preparation, prostheses maladaptation, and implant drilling.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Humanos , NF-kappa B/metabolismo , Interleucina-8/metabolismo , Titânio , Interleucina-6/metabolismo , Citocinas/metabolismo , Carcinoma de Células Escamosas/patologia , Neoplasias Bucais/patologia , Fibroblastos/metabolismo , Gengiva , Colágeno/metabolismo
2.
Clin Oral Investig ; 27(1): 125-137, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36018448

RESUMO

OBJECTIVES: To evaluate hydrogel-based scaffolds embedded with parathyroid hormone (PTH)-loaded mesoporous bioactive glass (MBG) on the enhancement of bone tissue regeneration in vitro. MATERIALS AND METHODS: MBG was produced via sol-gel technique followed by PTH solution imbibition. PTH-loaded MBG was blended into the hydrogels and submitted to a lyophilisation process associated with a chemical crosslinking reaction to the production of the scaffolds. Characterisation of the MBG and PTH-loaded MBG scaffolds, including the scanning electron microscope (SEM) connected with an X-ray detector (EDX), Fourier transform infrared (FTIR), compression strength, rheological measurements, swelling and degradation rates, and PTH release analysis, were performed. Also, bioactivity using simulated-body fluid (SBF), biocompatibility (MTT), and osteogenic differentiation analyses (von Kossa and Alizarin Red stainings, and µ-computed tomography, µCT) of the scaffolds were carried out. RESULTS: SEM images demonstrated MBG particles dispersed into the hydrogel-based scaffold structure, which was homogeneously porous and well interconnected. EDX and FTIR revealed large amounts of carbon, oxygen, sodium, and silica in the scaffold composition. Bioactivity experiments revealed changes on sample surfaces over the analysed period, indicating the formation of carbonated hydroxyapatite; however, the chemical composition remained stable. PTH-loaded hydrogel-based scaffolds were biocompatible for stem cells from human-exfoliated deciduous teeth (SHED). A high quantity of calcium deposits on the extracellular matrix of SHED was found for PTH-loaded hydrogel-based scaffolds. µCT images showed MBG particles dispersed into the scaffolds' structure, and a porous, lamellar, and interconnected hydrogel architecture. CONCLUSIONS: PTH-loaded hydrogel-based scaffolds demonstrated consistent morphology and physicochemical properties for bone tissue regeneration, as well as bioactivity, biocompatibility, and osteoinductivity in vitro. Thus, the scaffolds presented here are recommended for future studies on 3D printing. CLINICAL RELEVANCE: Bone tissue regeneration is still a challenge for several approaches to oral and maxillofacial surgeries, though tissue engineering applying SHED, scaffolds, and osteoinductive mediators might help to overcome this clinical issue.


Assuntos
Osteogênese , Tecidos Suporte , Humanos , Tecidos Suporte/química , Hormônio Paratireóideo/farmacologia , Hidrogéis/farmacologia , Regeneração Óssea , Vidro/química , Porosidade , Materiais Biocompatíveis/química
3.
Int J Mol Sci ; 23(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36077174

RESUMO

Enamel matrix derivative (EMD) prepared from extracted porcine fetal tooth material can support the regrow of periodontal tissues. Previous findings suggest that EMD has anti-inflammatory properties and TGF-ß activity in vitro. However, the anti-inflammatory activity of EMD is mediated via TGF-ß has not been considered. To this aim, we first established a bioassay to confirm the anti-inflammatory activity of EMD. The bioassay was based on the RAW 264.7 macrophage cell line and proven with primary macrophages where EMD significantly reduced the forced expression of IL-6. We then confirmed the presence of TGF-ß1 in EMD by immunoassay and by provoking the Smad2/3 nuclear translocation in RAW 264.7 macrophages. Next, we took advantage of the TGF-ß receptor type I kinase-inhibitor SB431542 to block the respective signalling pathway. SB431542 reversed the anti-inflammatory activity of EMD and TGF-ß in a bioassay when IL-6 and CXCL2 expression was driven by the LPS stimulation of RAW 264.7 macrophages. This central observation was supported by showing that SB431542 reversed the anti-inflammatory activity of EMD using IL-1ß and TNF-α-stimulated ST2 bone marrow stromal cells. Together, these findings implicate that the TGF-ß activity mediates at least part of the anti-inflammatory activity of EMD in vitro.


Assuntos
Proteínas do Esmalte Dentário , Interleucina-6 , Animais , Anti-Inflamatórios/farmacologia , Células Cultivadas , Proteínas do Esmalte Dentário/farmacologia , Suínos , Fator de Crescimento Transformador beta
4.
Int J Mol Sci ; 23(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35955441

RESUMO

BACKGROUND: Pyroptosis is a catabolic process relevant to periodontal disorders for which interleukin-1ß (IL-1ß) inflammation is central to the pathophysiology of the disease. Despite platelet-rich fibrin (PRF) anti-inflammatory properties and its application to support periodontal regeneration, the capacity of PRF to modulate pyroptosis, specifically the production and release of IL-1ß, remains unknown. The question arises whether PRF could regulate IL-1ß release from macrophages in vitro. METHODS: To answer this question, RAW 264.7 macrophages and primary macrophages obtained from murine bone marrow were primed with PRF before being challenged by lipopolysaccharide (LPS). Cells were then analysed for the pyroptosis signalling components by gene expression analyses and IL-1ß secretion at the protein level. The release of mitochondrial reactive oxygen species (ROS) was also detected. RESULTS: PRF lowered the LPS-induced expression of IL-1ß and NLRP3 inflammasome, caspase-11 and IL-18 in primary macrophages, and IL-1ß and caspase-11 in RAW 264.7 cells. Additionally, PRF diminished the secretion of IL-1ß at the protein level in LPS-induced RAW 264.7 cells. This was shown through immunoassays performed with the supernatant and further confirmed by analysing the lysates of permeabilised cells. Furthermore, PRF reduced the ROS release provoked by LPS in RAW 264.7 cells. Finally, to enhance IL-1ß release from the LPS-primed macrophages, we introduced a second signal with adenosine triphosphate (ATP). In this setting, PRF significantly reduced IL-1ß release in RAW 264.7 cells and a trend to diminish IL-1ß release in primary macrophages. CONCLUSION: These findings suggest that PRF can reduce IL-1ß release and, at least in part, inhibit pyroptosis-related factors in LPS-challenged macrophages.


Assuntos
Fibrina Rica em Plaquetas , Piroptose , Animais , Caspase 1/metabolismo , Caspases/metabolismo , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fibrina Rica em Plaquetas/metabolismo , Espécies Reativas de Oxigênio/metabolismo
5.
J Clin Med ; 11(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35887825

RESUMO

Damage to mesenchymal cells occurs by dental implant drills as a consequence of shear forces and heat generation. However, how the damaged mesenchymal cells can affect the polarization of macrophages and their differentiation into osteoclastogenesis is not fully understood. To simulate cell damage, we exposed suspended ST2 murine bone marrow stromal cells to freeze/thawing or sonication cycles, followed by centrifugation. We then evaluated the lysates for their capacity to modulate lipopolysaccharide-induced macrophage polarization and RANKL-MCSF-TGF-ß-induced osteoclastogenesis. We report that lysates of ST2, particularly when sonicated, greatly diminished the expression of inflammatory IL6 and COX2 as well as moderately increased arginase 1 in primary macrophages. That was confirmed by lysates obtained from the osteocytic cell line IDG-SW3. Moreover, the ST2 lysate lowered the phosphorylation of p65 and p38 as well as the nuclear translocation of p65. We further show herein that lysates of damaged ST2 reduced the formation of osteoclast-like cells characterized by their multinuclearity and the expression of tartrate-resistant phosphatase and cathepsin K. Taken together, our data suggest that thermal and mechanical damage of mesenchymal cells causes the release of as-yet-to-be-defined molecules that dampen an inflammatory response and the formation of osteoclasts in vitro.

6.
Life (Basel) ; 12(7)2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35888133

RESUMO

Periodontitis is an inflammatory process that is associated with caspase activity. Caspases could thus become molecular targets for the modulation of the inflammatory response to harmful factors, such as lipopolysaccharides (LPS) and TNFα. Here, the impact of the pan-caspase inhibitor Z-VAD-FMK (carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]-fluoro-methyl ketone) on the modulation of the LPS-induced inflammatory response of murine RAW 264.7 cells and primary macrophages was examined. Moreover, the inflammatory responses of human gingival fibroblasts, HSC2 oral squamous carcinoma cells and murine ST2 mesenchymal fibroblasts when exposed to TNFα were studied. Data showed that Z-VAD-FMK significantly lowered the inflammatory response of RAW 264.7 cells and primary macrophages, as indicated by the expression of IL1 and IL6. In murine ST2 mesenchymal fibroblasts, the TNFα-induced expression of CCL2 and CCL5 was significantly reduced. In human gingival fibroblasts and HSC2 cells, Z-VAD-FMK considerably reduced the TNFα-induced expression of CXCL8 and CXCL10. These findings suggest that pharmacological blocking of caspases in an inflammatory environment lowers the expression of cytokines and chemokines in periodontal cells.

7.
Int J Mol Sci ; 23(9)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35563469

RESUMO

Background: Pyroptosis is a caspase-dependent catabolic process relevant to periodontal disorders for which inflammation is central to the pathophysiology of the disease. Although enamel matrix derivative (EMD) has been applied to support periodontal regeneration, its capacity to modulate the expression of pyroptosis-related genes remains unknown. Considering EMD has anti-inflammatory properties and pyroptosis is linked to the activation of the inflammasome in chronic periodontitis, the question arises whether EMD could reduce pyroptosis signalling. Methods: To answer this question, primary macrophages obtained from murine bone marrow and RAW 264.7 macrophages were primed with EMD before being challenged by lipopolysaccharide (LPS). Cells were then analysed for pyroptosis-signalling components by gene expression analyses, interleukin-1ß (IL-1ß) immunoassay, and the detection of caspase-1 (CAS1). The release of mitochondrial reactive oxygen species (ROS) was also detected. Results: We report here that EMD, like the inflammasome (NLRP3) and CAS1 specific inhibitors-MCC950 and Ac-YVAD-cmk, respectively-lowered the LPS-induced expression of NLRP3 in primary macrophages (EMD: p = 0.0232; MCC950: p = 0.0426; Ac-YVAD-cmk: p = 0.0317). EMD further reduced the LPS-induced expression of NLRP3 in RAW 264.7 cells (p = 0.0043). There was also a reduction in CAS1 and IL-1ß in RAW 264.7 macrophages on the transcriptional level (p = 0.0598; p = 0.0283; respectively), in IL-1ß protein release (p = 0.0313), and CAS1 activity. Consistently, EMD, like MCC950 and Ac-YVAD-cmk, diminished the ROS release in activated RAW 264.7 cells. In ST2 murine mesenchymal cells, EMD could not be tested because LPS, saliva, and IL-1ß + TNF-α failed to provoke pyroptosis signalling. Conclusion: These findings suggest that EMD is capable of dampening the expression of pyroptosis-related genes in macrophages.


Assuntos
Periodontite Crônica , Macrófagos , Piroptose , Animais , Caspase 1/genética , Caspase 1/metabolismo , Caspases/metabolismo , Periodontite Crônica/genética , Periodontite Crônica/metabolismo , Proteínas do Esmalte Dentário/farmacologia , Proteínas do Esmalte Dentário/uso terapêutico , Inflamassomos/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose/genética , Espécies Reativas de Oxigênio/metabolismo
8.
Molecules ; 27(4)2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35209110

RESUMO

Dalbergia cochinchinensis has been widely used in traditional medicine because of its flavonoids; however, the impact of the flavonoids to modulate the inflammatory response to oral cells remains to be described. For this aim, we isolated 4,7,2'-trihydroxy-4'-methoxyisoflavanol (472T4MIF) and 6,4'-dihydroxy-7-methoxyflavane (64D7MF) from the heartwood of D. cochinchinensis and confirmed the chemical structure by nuclear magnetic resonance. We show here that both flavonoids are inhibitors of an inflammatory response of murine RAW 264.7 inflammatory macrophages stimulated by LPS. This is indicated by interleukin (IL)1, IL6, and chemokine CCL2 production besides the phosphorylation of p65. Consistently, in primary murine macrophages, both flavonoids decreased the inflammatory response by lowering LPS-induced IL1 and IL6 expression. To introduce oral cells, we have used human gingival fibroblasts and provoked the inflammatory response by exposing them to IL1ß and TNFα. Under these conditions, 472T4MIF, but not 64D7MF, reduced the expression of chemokines CXCL1 and CXCL2. Taken together, we identified two flavonoids that can reduce the expression of cytokines and chemokines in macrophages and fibroblastic cells.


Assuntos
Quimiocinas/genética , Citocinas/genética , Dalbergia/química , Flavonoides/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Madeira/química , Animais , Quimiocinas/metabolismo , Citocinas/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Flavonoides/química , Flavonoides/isolamento & purificação , Camundongos , Estrutura Molecular , Fosforilação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Células RAW 264.7
9.
Int J Periodontics Restorative Dent ; 41(4): e157-e165, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34328477

RESUMO

Using autogenous grafts in mucogingival surgeries is related to postoperative morbidity and limited tissue availability, and thus xenogeneic matrices are increasingly used. This in vitro study evaluated the influence of xenogeneic collagen matrix thickness on cell adhesion, morphology, viability, proliferation, and matrix degradation. Matrices were divided into three groups: SLC: single layer of Lumina Coat, as commercially available (2-mm thickness); DLC: double layer of SLC (Lumina Coat); and MG: single layer of Mucograft, as commercially available (4-mm thickness). SEM was used to evaluate the matrix surface topographies. To evaluate the cell viability, proliferation, adhesion, and morphology, human gingival fibroblasts (HGF) and stem cells from human exfoliated deciduous teeth (SHED) were used. Cell viability was evaluated through MTS colorimetric method evaluating HGF and SHED on days 1, 3, and 7. Cell proliferation was assessed by PicoGreen assay, evaluating HGF and SHED on days 3 and 7. Sample degradation was evaluated on days 1, 3, 7, 14, 21, 28, and 35. All groups were biocompatible for HGF and SHED, showing viabilities > 70% on days 1, 3, and 7. DCL promoted HGF viabilities similar to MG (P = .2828) and the highest SHED viability (P < .0001) on day 1. DLC also demonstrated HGF and SHED proliferations higher than the positive control (MG; P < .05) on day 7. SLC was completely degraded on day 14, while DLC and MG presented 48.41% and 20.52% of their initial mass, respectively, on day 35. Increasing the matrix thickness improved HGF and SHED viability and proliferation and prevented early matrix degradation. DLC demonstrated better results than SLC and MG concerning matrix degradation and HGF and SHED viability and proliferation.


Assuntos
Células-Tronco Mesenquimais , Proliferação de Células , Células Cultivadas , Colágeno , Fibroblastos , Humanos
10.
J Mater Sci Mater Med ; 32(1): 1, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469820

RESUMO

In in vitro culture systems, dexamethasone (DEX) has been applied with ascorbic acid (ASC) and ß-glycerophosphate (ßGLY) as culture media supplementation to induce osteogenic differentiation of mesenchymal stem cells. However, there are some inconsistencies regarding the role of DEX as osteogenic media supplementation. Therefore, this study verified the influence of DEX culture media supplementation on the osteogenic differentiation, especially the capacity to mineralize the extracellular matrix of stem cells from human exfoliated deciduous teeth (SHED). Five groups were established: G1-SHED + Dulbecco's Modified Eagles' Medium (DMEM) + fetal bovine serum (FBS); G2-SHED + DMEM + FBS + DEX; G3-SHED + DMEM + FBS + ASC + ßGLY; G4-SHED + DMEM + FBS + ASC + ßGLY + DEX; G5-MC3T3-E1 + α Minimal Essential Medium (MEM) + FBS + ASC + ßGLY. DNA content, alkaline phosphatase (ALP) activity, free calcium quantification in the extracellular medium, and extracellular matrix mineralization quantification through staining with von Kossa, alizarin red, and tetracycline were performed on days 7 and 21. Osteogenic media supplemented with ASC and ß-GLY demonstrated similar effects on SHED in the presence or absence of DEX for DNA content (day 21) and capacity to mineralize the extracellular matrix according to alizarin red and tetracycline quantifications (day 21). In addition, the presence of DEX in the osteogenic medium promoted less ALP activity (day 7) and extracellular matrix mineralization according to the von Kossa assay (day 21), and more free calcium quantification at extracellular medium (day 21). In summary, the presence of DEX in the osteogenic media supplementation did not interfere with SHED commitment into mineral matrix depositor cells. We suggest that DEX may be omitted from culture media supplementation for SHED osteogenic differentiation in vitro studies.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Dexametasona/farmacologia , Osteogênese/efeitos dos fármacos , Células-Tronco/citologia , Dente Decíduo/metabolismo , Células 3T3 , Animais , Ácido Ascórbico/química , Cálcio/metabolismo , Meios de Cultura , DNA/metabolismo , Matriz Extracelular/metabolismo , Glicerofosfatos/química , Humanos , Técnicas In Vitro , Camundongos
11.
J Oral Implantol ; 47(2): 93-101, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32699891

RESUMO

The aim of this study was to synthesize, characterize, and evaluate degradation and biocompatibility of poly(lactic-co-glycolic acid) + hydroxyapatite/ß-tricalcium phosphate (PLGA+HA/ßTCP) scaffolds incorporating simvastatin (SIM) to verify if this biomaterial might be promising for bone tissue engineering. Samples were obtained by the solvent evaporation technique. Biphasic ceramic particles (70% HA, 30% ßTCP) were added to PLGA in a ratio of 1:1. Samples with SIM received 1% (m/m) of this medication. Scaffolds were synthesized in a cylindric shape and sterilized by ethylene oxide. For degradation analysis, samples were immersed in phosphate-buffered saline at 37°C under constant stirring for 7, 14, 21, and 28 days. Nondegraded samples were taken as reference. Mass variation, scanning electron microscopy, porosity analysis, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetry were performed to evaluate physico-chemical properties. Wettability and cytotoxicity tests were conducted to evaluate the biocompatibility. Microscopic images revealed the presence of macro-, meso-, and micropores in the polymer structure with HA/ßTCP particles homogeneously dispersed. Chemical and thermal analyses presented similar results for both PLGA+HA/ßTCP and PLGA+HA/ßTCP+SIM. The incorporation of simvastatin improved the hydrophilicity of scaffolds. Additionally, PLGA+HA/ßTCP and PLGA+HA/ßTCP+SIM scaffolds were biocompatible for osteoblasts and mesenchymal stem cells. In summary, PLGA+HA/ßTCP scaffolds incorporating simvastatin presented adequate structural, chemical, thermal, and biological properties for bone tissue engineering.


Assuntos
Materiais Biocompatíveis , Engenharia Tecidual , Fosfatos de Cálcio , Ácido Láctico , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Porosidade , Sinvastatina , Tecidos Suporte
12.
Int J Mol Sci ; 23(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35008798

RESUMO

Pyroptosis is a caspase-dependent process relevant to the understanding of beneficial host responses and medical conditions for which inflammation is central to the pathophysiology of the disease. Pyroptosis has been recently suggested as one of the pathways of exacerbated inflammation of periodontal tissues. Hence, this focused review aims to discuss pyroptosis as a pathological mechanism in the cause of periodontitis. The included articles presented similarities regarding methods, type of cells applied, and cell stimulation, as the outcomes also point to the same direction considering the cellular events. The collected data indicate that virulence factors present in the diseased periodontal tissues initiate the inflammasome route of tissue destruction with caspase activation, cleavage of gasdermin D, and secretion of interleukins IL-1ß and IL-18. Consequently, removing periopathogens' virulence factors that trigger pyroptosis is a potential strategy to combat periodontal disease and regain tissue homeostasis.


Assuntos
Doenças Periodontais/patologia , Piroptose , Animais , Apoptose , Humanos , Inflamassomos/metabolismo , Doenças Periodontais/terapia , Fatores de Virulência/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-33575012

RESUMO

Background. Local or systemic issues might prevent installing a sufficient number of dental implants for fixed prosthetic rehabilitation. Splinting dental implants and natural teeth in fixed dentures could overcome such limitations. Therefore, this study aimed to evaluate the influence of the number of dental abutments in the biomechanics of tooth‒implant-supported fixed partial dentures (FPDs). The null hypothesis was that increasing the number of abutment teeth would not decrease the stress over the abutments and surrounding bone. Methods. Left mandibular lateral incisor, canine, premolars, and molars were reconstructed through computed tomography and edited using image processing software to represent a cemented fixed metal‒ceramic partial denture. Three models were set to reduce the number of abutment teeth: 1) lateral incisor, canine, and first premolar; 2) canine and first premolar; 3) the first premolar. The second premolar and first molar were set as pontics, and the second molar was set as an implant abutment in all the models. Finite element analyses were performed under physiologic masticatory forces with axial and oblique loading vectors. Results. After simulation of axial loads, the stress peaks on the bone around the implant, the bone around the first premolar, and prosthetic structures did not exhibit significant changes when the number of abutment teeth decreased. However, under oblique loads, decreasing the number of abutment teeth increased stress peaks on the surrounding bone and denture. Conclusion. Increasing the number of dental abutments in tooth‒implant-supported cemented FPD models decreased stresses on its constituents, favoring the prosthetic biomechanics.

14.
J Appl Oral Sci ; 26: e20170065, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29489934

RESUMO

Considering oral diseases, antibiofilm compounds can decrease the accumulation of pathogenic species such as Streptococcus mutans at micro-areas of teeth, dental restorations or implant-supported prostheses. OBJECTIVE: To assess the effect of thirteen different novel lactam-based compounds on the inhibition of S. mutans biofilm formation. MATERIAL AND METHODS: We synthesized compounds based on γ-lactones analogues from rubrolides by a mucochloric acid process and converted them into their corresponding γ-hydroxy-γ-lactams by a reaction with isobutylamine and propylamine. Compounds concentrations ranging from 0.17 up to 87.5 µg mL-1 were tested against S. mutans. We diluted the exponential cultures in TSB and incubated them (37°C) in the presence of different γ-lactones or γ-lactams dilutions. Afterwards, we measured the planktonic growth by optical density at 630 nm and therefore assessed the biofilm density by the crystal violet staining method. RESULTS: Twelve compounds were active against biofilm formation, showing no effect on bacterial viability. Only one compound was inactive against both planktonic and biofilm growth. The highest biofilm inhibition (inhibition rate above 60%) was obtained for two compounds while three other compounds revealed an inhibition rate above 40%. CONCLUSIONS: Twelve of the thirteen compounds revealed effective inhibition of S. mutans biofilm formation, with eight of them showing a specific antibiofilm effect.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Lactonas/farmacologia , Streptococcus mutans/efeitos dos fármacos , beta-Lactamas/farmacologia , Análise de Variância , Antibacterianos/síntese química , Biofilmes/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Violeta Genciana , Lactonas/síntese química , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Plâncton/efeitos dos fármacos , Plâncton/crescimento & desenvolvimento , Reprodutibilidade dos Testes , Streptococcus mutans/crescimento & desenvolvimento , Resistência beta-Lactâmica/efeitos dos fármacos , beta-Lactamas/síntese química
15.
J. appl. oral sci ; 26: e20170065, 2018. graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-893689

RESUMO

Abstract Considering oral diseases, antibiofilm compounds can decrease the accumulation of pathogenic species such as Streptococcus mutans at micro-areas of teeth, dental restorations or implant-supported prostheses. Objective To assess the effect of thirteen different novel lactam-based compounds on the inhibition of S. mutans biofilm formation. Material and methods We synthesized compounds based on γ-lactones analogues from rubrolides by a mucochloric acid process and converted them into their corresponding γ-hydroxy-γ-lactams by a reaction with isobutylamine and propylamine. Compounds concentrations ranging from 0.17 up to 87.5 μg mL-1 were tested against S. mutans. We diluted the exponential cultures in TSB and incubated them (37°C) in the presence of different γ-lactones or γ-lactams dilutions. Afterwards, we measured the planktonic growth by optical density at 630 nm and therefore assessed the biofilm density by the crystal violet staining method. Results Twelve compounds were active against biofilm formation, showing no effect on bacterial viability. Only one compound was inactive against both planktonic and biofilm growth. The highest biofilm inhibition (inhibition rate above 60%) was obtained for two compounds while three other compounds revealed an inhibition rate above 40%. Conclusions Twelve of the thirteen compounds revealed effective inhibition of S. mutans biofilm formation, with eight of them showing a specific antibiofilm effect.


Assuntos
Streptococcus mutans/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , beta-Lactamas/farmacologia , Lactonas/farmacologia , Antibacterianos/farmacologia , Plâncton/crescimento & desenvolvimento , Plâncton/efeitos dos fármacos , Streptococcus mutans/crescimento & desenvolvimento , Microscopia Eletrônica de Varredura , Contagem de Colônia Microbiana , Testes de Sensibilidade Microbiana , Reprodutibilidade dos Testes , Análise de Variância , Biofilmes/crescimento & desenvolvimento , Resistência beta-Lactâmica/efeitos dos fármacos , beta-Lactamas/síntese química , Relação Dose-Resposta a Droga , Viabilidade Microbiana/efeitos dos fármacos , Violeta Genciana , Lactonas/síntese química , Antibacterianos/síntese química
16.
Braz Oral Res ; 31: e102, 2017 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-29267663

RESUMO

The objective of this study was to assess the oral health status of users of illicit drugs such as marijuana and cocaine/crack and compare it with individuals not using these chemical substances. Questionnaires were applied to 35 illicit drugs users to gather information on demographic status, general health, and use of drugs. Then, a clinical assessment of the oral health condition was performed to collect data on decayed, missing and filled teeth (DMFT) index, salivary flow rate (SFR), and mucosal lesions. The control group was composed of 35 non-illicit drug users. In the experimental group, 91.43% were males, 80% were smokers, and 42.85% were alcoholics. Cocaine was the most common drug used (77.15%), followed by marijuana (68.6%), and crack (51.4%). The average DMFT index was 9.8 and the SFR was reduced in 60% of subjects. Mucosal alterations were detected, but no potentially malignant disorders or oral cancer were diagnosed. Compared to control group, significantly higher values for gender (40%, p = 0.0001), smoking (22.86%) and heavy drinking (5.7%) habits (p = 0.0001), SFR (31.4%; p = 0.0308), and oral lesions (p = 0.0488) were found for the experimental group, although significantly higher values were found in the control group for DMFT index (p = 0.0148). It can be concluded that the use of illicit drugs contributed to an increased prevalence of oral mucosa lesions. In addition, a decline on SFR and a reduced DMFT index was observed for illicit drug users.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/complicações , Abuso de Maconha/complicações , Doenças da Boca/induzido quimicamente , Mucosa Bucal/efeitos dos fármacos , Saúde Bucal/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Alcoolismo/complicações , Alcoolismo/epidemiologia , Estudos de Casos e Controles , Transtornos Relacionados ao Uso de Cocaína/epidemiologia , Estudos Transversais , Índice CPO , Feminino , Humanos , Masculino , Abuso de Maconha/epidemiologia , Pessoa de Meia-Idade , Doenças da Boca/epidemiologia , Fatores de Risco , Salivação/efeitos dos fármacos , Taxa Secretória/efeitos dos fármacos , Distribuição por Sexo , Fumar/efeitos adversos , Fumar/epidemiologia , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
17.
ImplantNewsPerio ; 1(7): 1357-1367, out.-nov. 2016. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-848033

RESUMO

O objetivo deste trabalho foi apresentar um caso clínico de reabilitação entre dentes e implantes. Na situação inicial, havia escurecimento do dente 11 e ausência do dente 22, sobre o qual estava instalada uma prótese parcial removível. Uma intensa reabsorção óssea na região do dente ausente foi observada através de análises clínica e tomográfica. A técnica de expansão óssea associada ao deslocamento vestibular de tecido conjuntivo palatino, conhecido como "técnica do rolo", foi realizada, juntamente à instalação de implante cone-morse (Arcsys). Após quatro meses, foi realizada a reabertura. Selecionou-se um munhão universal angulável (Arcsys), o qual teve sua angulação personalizada com base na posição obtida através de um referenciador angular, e uma prótese provisória cimentada foi confeccionada sobre este. Um preparo para coroa metalocerâmica foi realizado no dente 11 e sobre o elemento 21, além da substituição das restaurações antigas, também foi realizada faceta em resina composta. Assim, o caso foi finalizado com uma coroa metalocerâmica sobre implante e uma coroa metalocerâmica sobre dente, entremeadas por dente natural facetado com resina composta. Apesar da complexidade de um caso clínico envolvendo dentes naturais e próteses, foi possível alcançar um resultado satisfatório e um sorriso esteticamente harmônico.


The aim of this paper was to present a clinical rehabilitation case with teeth and implants. In the clinical scenario, there was darkening of tooth 11 and the lack of tooth 22, where a removable prosthesis was installed. Also, considerable bone resorption was observed after clinical and CBCT exams. In this way, bone expansion technique was associated to the roll technique. Four months after implant placement, (morse taper, Arcsys), the opening procedure was performed. A universal abutment (Arcsys) was selected and angled in real time according a pre-fabricated guiding device, receiving a cemented provisional single-tooth crown. Then, tooth 11 received a dental preparation for fused-to-metal crown, and tooth 21 received a direct composite veneer. Thus, the final scenario was composed by a fused-to-metal crowns over dental implant and tooth, and a natural tooth with resin composite veneer. Despite its complexity, satisfactory results and a harmonious smile were achieved.


Assuntos
Humanos , Feminino , Adulto , Regeneração Óssea , Implantes Dentários para Um Único Dente , Prótese Dentária Fixada por Implante , Prótese Parcial Fixa , Reabilitação Bucal , Transplante de Tecidos
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