Orthodontic force increases interleukin-1β and tumor necrosis factor-α expression and alveolar bone loss in periodontitis

Background: The present study aims to evaluate the effects of orthodontic movement (OM) on the periodontal tissues of rats with ligature-induced periodontal disease. Methods: Eighty-eight rats were divided into four groups: 1) negative control (sham operated); 2) periodontal disease; 3) OM; and 4) periodontal disease followed by OM (OMP). Rats were sacrificed 3 hours or 1, 3, or 7 days after OM commencement. Bone volume fraction (BVF) and bone mineral density (BMD) were assessed in hemimaxillae by microcomputed tomography analysis. Expression of the proinflammatory cytokines interleukin (IL)-1β and tumor necrosis factor (TNF)-α were evaluated in gingival samples by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay, and in the furcation region by immunohistochemistry analysis (IHC). Results: The OMP group had lower BVF and BMD levels compared to the other groups at day 7 (P <0.05). Maximum messenger ribonucleic acid expression of both cytokines was observed in the OMP group at day 1 (P <0.05). In the same period, all proteins were expressed in high levels for all test groups compared to the control group. The number of cells positive for IL-1β and TNF-α by IHC was highest in the OMP group at day 1, with progressive reduction thereafter. Conclusion: The results suggest that OM acts synergistically with periodontal disease in periodontal breakdown through upregulation of proinflammatory cytokines.

The role of cytokines in inflammatory bone loss

Chronic inflammatory processes close to bone often lead to loss of bone in diseases such as rheumatoid arthritis, periodontitis, loosened joint prosthesis and tooth implants. This is mainly due to local formation of bone resorbing osteoclasts which degrade bone without any subsequent coupling to new bone formation. Crucial for osteoclastogenesis is stimulation of mononuclear osteoclast progenitors by macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor-κB ligand (RANKL) which induces their differentiation along the osteoclastic lineage and the fusion to mature, multinucleated osteoclasts. M-CSF and RANKL are produced by osteoblasts/ osteocytes and by synovial and periodontal fibroblasts and the expression is regulated by pro- and anti-inflammatory cytokines. These cytokines also regulate osteoclastic differentiation by direct effects on the progenitor cells. In the present overview, we introduce the basic concepts of osteoclast progenitor cell differentiation and summarize the current knowledge on cytokines stimulating and inhibiting osteoclastogenesis by direct and indirect mechanisms. © Informa Healthcare USA, Inc.

Estudo das propriedades térmicas e mecânicas de blendas de PVDF/PANI

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise da influência dos sistemas de retenção para overdentures implanto-retidas e da espessura e resiliência da fibromucosa na distribuição interna das tensões, através do método de elementos finitos bidimensional

Pós-graduação em Odontologia - FOA

Efeito da irradiação por microondas sobre as propriedades viscoelásticas de resinas para base de prótese e reembasamento

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação do desempenho de compósitos de PPA/Fibra de vidro para aplicação em bombas de óleo de motores de motocicletas

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Aplicação da rede neural MLP (Multilayer Perceptron) em indústria de pisos e revestimentos do Pólo Cerâmico de Santa Gertrudes - SP

Pós-graduação em Geociências e Meio Ambiente - IGCE

Caracterização de materiais experimentais e comerciais para reembasamento imediato por meio de análise de propriedades físico-químicas e mecânicas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização de resinas para base de prótese e reembasamento: propriedades físico-químicas e mecânicas

Pós-graduação em Reabilitação Oral - FOAR

Citotoxicidade transdentinária e efeito da carbodiimida (EDC) na biomodificação do colágeno dentinário e na degradação da interface adesiva

Pós-graduação em Ciências Odontológicas - FOAR

MODEL-BASED COMPENSATION FOR BURST MESSAGE LOSS IN WIRELESS NETWORKED CONTROL SYSTEMS: EXPERIMENTAL RESULTS

A recent trend in networked control systems (NCSs) is the use of wireless networks enabling interoperability between existing wired and wireless systems. One of the major challenges in these wireless NCSs (WNCSs) is to overcome the impact of the message loss that degrades the performance and stability of these systems. Moreover, this impact is greater when dealing with burst or successive message losses. This paper discusses and presents the experimental results of a compensation strategy to deal with this burst message loss problem in which a NCS mathematical model runs in parallel with the physical process, providing sensor virtual data in case of packet losses. Running in real-time inside the controller, the mathematical model is updated online with real control signals sent to the actuator, which provides better reliability for the estimated sensor feedback (virtual data) transmitted to the controller each time a message loss occurs. In order to verify the advantages of applying this model-based compensation strategy for burst message losses in WNCSs, the control performance of a motor control system using CAN and ZigBee networks is analyzed. Experimental results led to the conclusion that the developed compensation strategy provided robustness and could maintain the control performance of the WNCS against different message loss scenarios.

Latent heat loss and sweat gland histology of male goats in an equatorial semi-arid environment

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Resin composite characterizations following a simplified protocol of accelerated aging as a function of the expiration date

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The Influence of Small Quantities of Oxygen in the Structure, Microstructure, Hardness, Elasticity Modulus and Cytocompatibility of Ti-Zr Alloys for Dental Applications

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)