941 resultados para tibial plato leveling osteotomy
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IL-17 is an important cytokine in the physiopathology of rheumatoid arthritis (RA). However, its participation in the genesis of nociception during RA remains undetermined. In this study, we evaluated the role of IL-17 in the genesis of articular nociception in a model of antigen (mBSA)-induced arthritis. We found that mBSA challenge in the femur-tibial joint of immunized mice induced a dose-and time-dependent mechanical hypernociception. The local IL-17 concentration within the mBSA-injected joints increased significantly over time. Moreover, co-treatment of mBSA challenged mice with an antibody against IL-17 inhibited hypernociception and neutrophil recruitment. In agreement, intraarticular injection of IL-17 induced hypernociception and neutrophil migration, which were reduced by the pre-treatment with fucoidin, a leukocyte adhesion inhibitor. The hypernociceptive effect of IL-17 was also reduced in TNFR1(-/-) mice and by pre-treatment with infliximab (anti-TNF antibody), a CXCR1/2 antagonist or by an IL-1 receptor antagonist. Consistent with these findings, we found that IL-17 injection into joints increased the production of TNF-alpha, IL-1 beta and CXCL1/KC. Treatment with doxycycline (non-specific MMPs inhibitor), bosentan (ET(A)/ET(B) antagonist), indomethacin (COX inhibitor) or guanethidine (sympathetic blocker) inhibited IL-17-induced hypernociception. IL-17 injection also increased PGE(2) production, MMP-9 activity and COX-2, MMP-9 and PPET-1 mRNA expression in synovial membrane. These results suggest that IL-17 is a novel pro-nociceptive cytokine in mBSA-induced arthritis, whose effect depends on both neutrophil migration and various pro-inflammatory mediators, as TNF-alpha, IL-1 beta, CXCR1/2 chemokines ligands, MMPs, endothelins, prostaglandins and sympathetic amines. Therefore, it is reasonable to propose IL-17 targeting therapies to control this important RA symptom. (C) 2009 International Association for the Study of Pain. Published by Elsevier B. V. All rights reserved.
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Bone transport is based on the principle of distraction osteogenesis described by Ilizarov and is a consecrated method for the treatment of segmental bone defects. One of its most problematic and, paradoxically, least studied aspects is the consolidation of the docking site. We studied histologically the ossification of the docking site and regenerate to determine any difference between them. Nine adult sheep were submitted to correction of a 1-cm tibial diaphyseal defect using a system of plate-fixed bone transport, with latency period of 1 week and 0.2 mm distraction of the transported segment four times a day. The sheep were divided into three groups of three animals each, according to the observation period of 3, 6 or 12 weeks between the fixation of the transported fragment and the euthanasia. The docking site and the regenerate were studied histologically on sections stained with Masson trichrome. The main mode of docking site ossification was the endochondral one and although intramembranous ossification was also observed simultaneously, it was limited to rare and small foci. In contrast, intramembranous ossification played the major role in the regenerate, with bone formation evolving from the base segment to the target segment. The experimental bone transport model proposed in the present study permits us to conclude that there is a clear difference between the ossification of the docking site and of the regenerate.
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Cell therapy constitutes a possibility for improving nerve regeneration, increasing the success of nerve repair. We evaluate the use of mononuclear cells in the regeneration of the sciatic nerve after axotomy followed by end-to-end neurorrhaphy. Forty adult male Wistar rats (250300 g) were divided into four groups: (1) sham, (2) neurorrhaphy: the sciatic nerve was sectioned and repaired using epineural sutures, (3) culture medium: after the suture, received an injection of 10 mu L of culture medium into the nerve, and (4) mononuclear cell: after the suture, a concentration of 3 X 10(6) of mononuclear cell was injected in epineurium region. Mononuclear cells were obtained from the bone marrow aspirates and separated by Ficoll-Hypaque method. The histological analyses were performed at the 4th postoperative day. The sciatic functional index, histological, and morphometric analyzes were used to evaluate nerve regeneration at the 6th postoperative week. Six rats were used for immunohistochemical analysis on the 4th postoperative day. In the group 4, on the fourth day, the histological analysis demonstrated a more accelerated degenerative process and an increase of the neurotrophic factors was observed. In the 6th week, all the morphometric results of the group 4 were statistically better compared with groups 2 and 3. There was a statistically significant improvement in the sciatic functional index for group 4 compared with groups 2 and 3. Mononuclear cells stimulated nerve regeneration, most probably by speeding up the Wallerian degeneration process as well as stimulating the synthesis of neurotrophic factors. Microsc. Res. Tech. 74:355-363, 2011. (C) 2010 Wiley-Liss, Inc.
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We assessed the repair of transverse, 3-mm wide bone gaps created at the distal radius in 28 dogs that were randomly divided into two 14-animal groups; one was the control group and the other received a daily, 20-min application of low-intensity pulsed ultrasound for 100 days. Sequential radiographs, histomorphometrics, bone fluorescent histology and bone vascularity assessments found that all animals from both groups obtained a stage of hypertrophic-type nonunion with fibrocartilage tissue formation throughout the region of osteotomy. However, treated animals exhibited areas of endochondral ossification within the fibrocartilage region. There was no difference in type of vascularity or the newly formed bone process obtained by tetracycline labeling. Application of low-intensity ultrasound was not capable of significantly changing the reparative process and it may not be sufficiently powerful to overcome a combination of local deleterious effects on bone healing, created by gapping, excessive motion and periosteal resection. (E-mail: jbvolpon@fmrp.usp.br) (C) 2010 World Federation for Ultrasound in Medicine & Biology.
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Establishment of a treatment plan is based on efficacy and easy application by the clinician, and acceptance by the patient. Treatment of adult patients with Class III malocclusion might require orthognathic surgery, especially when the deformity is severe, with a significant impact on facial esthetics. Impacted teeth can remarkably influence treatment planning, which should be precise and concise to allow a reasonably short treatment time with low biologic cost. We report here the case of a 20-year-old man who had a skeletal Class III malocclusion and impaction of the maxillary right canine, leading to remarkable deviation of the maxillary midline; this was his chief complaint. Because of the severely deviated position of the impacted canine, treatment included extraction of the maxillary right canine and left first premolar for midline correction followed by leveling, alignment, correction of compensatory tooth positioning, and orthognathic surgery to correct the skeletal Class III malocclusion because of the severe maxillary deficiency. This treatment approach allowed correction of the maxillary dental midline discrepancy to the midsagittal plane and establishment of good occlusion and optimal esthetics. (Am J Orthod Dentofacial Orthop 2010;137:840-9)
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Introduction: The aim of this study was to evaluate the dentoskeletal and soft-tissue effects of Class II malocclusion treatment with the Jasper jumper followed by Class II elastics at the different stages of therapy. Methods: The sample comprised 24 patients of both sexes (11 boys, 13 girls) with an initial age of 12.58 years, treated for a mean period of 2.15 years. Four lateral cephalograms were obtained of each patient in these stages of orthodontic treatment: at pretreatment (T1), after leveling and alignment (T2), after the use of the Jasper jumper appliance and before the use of Class II intermaxillary elastics (T3), and at posttreatment (T4). Thus, 3 treatment phases could be evaluated: leveling and alignment (T1-T2), use of the Jasper jumper (T2-T3), and use of Class II elastics (T3-T4). Dependent analysis of variance (ANOVA) and Tukey tests were used to compare the durations of the 3 treatment phases and for intragroup comparisons of the 4 treatment stages. Results: The alignment phase showed correction of the anteroposterior relationship, protrusion and labial inclination of the maxillary incisors, and reduction of overbite. The Jasper jumper phase demonstrated labial inclination, protrusion and intrusion of the mandibular incisors, mesialization and extrusion of the mandibular molars, reduction of overjet and overbite, molar relationship improvement, and reduction in facial convexity. The Class II elastics phase showed labial inclination of the maxillary incisors; retrusion, uprighting, and extrusion of the mandibular incisors; and overjet and overbite increases. Conclusions: The greatest amount of the Class II malocclusion anteroposterior discrepancy was corrected with the Jasper jumper appliance. Part of the correction was lost during Class II intermaxillary elastics use after use of the Jasper jumper appliance. (Am J Orthod Dentofacial Orthop 2011;140:e77-e84)
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Objectives. The objective of this study was to elucidate the changes occurring in the temporomandibular joint (TMJ) after surgical mandibular advancement with different fixation techniques: bicortical screws (rigid fixation) and miniplates (semi-rigid fixation). Study design. Eighteen minipigs were equally and randomly divided into 3 groups: Group I (control), nonoperated animals; Group II, animals submitted to surgical advancement surgery and osteosynthesis by bicortical screws; and Group III, animals submitted to surgical advancement surgery and osteosynthesis by miniplates. Four months after the surgeries, the presence of interleukin (IL)-6 and IL-10 in synovial fluid samples was assessed in ELISA experiments. TMJs were histologically prepared. Results. Higher levels of IL-10 (P = .0436) were found for Group II. Descriptive histological analysis was compatible with the ELISA findings. Conclusions. Rigid fixation evokes more pronounced signs of bone remodeling in the TMJ, whereas malleable fixation promotes a more intense inflammatory activity. Therefore, rigid fixation seems to transmit a higher impact of postoperative masticatory forces to the TMJ.
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Purpose: To evaluate the biomechanical fixation, bone-to-implant contact (BIC), and bone morphology of screw-type root-form implants with healing chambers with as-machined or dual acid-etched (DAE) surfaces in a canine model. Materials and Methods: The animal model included the placement of machined (n = 24) and DAE (n = 24) implants along the proximal tibiae of six mongrel dogs, which remained in place for 2 or 4 weeks. Following euthanasia, half of the specimens were subjected to biomechanical testing (torque to interface failure) and the other half were processed for histomorphologic and histomorphometric (%BIC) assessments. Statistical analyses were performed by one-way analysis of variance at the 95% confidence level and the Tukey post hoc test for multiple comparisons. Results: At 4 weeks, the DAE surface presented significantly higher mean values for torque to interface failure overall. A significant increase in %BIC values occurred for both groups over time. For both groups, bone formation through the classic appositional healing pathway was observed in regions where intimate contact between the implant and the osteotomy walls occurred immediately after implantation. Where contact-free spaces existed after implantation (healing chambers), an intramembranous-like healing mode with newly formed woven bone prevailed. Conclusions: In the present short-term evaluation, no differences were observed in BIC between groups; however, an increase in biomechanical fixation was seen from 2 to 4 weeks with the DAE surface. INT J ORAL MAXILLOFAC IMPLANTS 2011;26:75-82
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Objective: This study compared the clinical efficacy of 4% articaine (A200) and 0.5% bupivacaine (B200), both with 1: 200,000 epinephrine, for lower third molar removal. Study design: Fifty patients underwent removal of symmetrically positioned lower third molars, in 2 separate appointments, under local anesthesia either with A200 or B200, in a double-blind, randomized, and crossover manner. Time to onset, duration of postoperative analgesia, duration of anesthetic action on soft tissues, intraoperative bleeding, and hemodynamic parameters were evaluated. Results: A statistically significant difference between the time to onset of A200 (1.66 +/- 0.13 minutes) and B200 (2.51 +/- 0.21 minutes) was found (P < .05). There was no statistically significant difference in the duration of analgesia, whether the patient was subjected to osteotomy or not, regardless of the local anesthetic used (3 to 4 hours; P < .05). However, when patients received B200 they experienced a statistically significant longer period of anesthesia on the soft tissues as compared with when they had received A200 (around 5 hours and 4 hours, respectively, P < .05). The surgeon`s rating of intraoperative bleeding was considered very close to minimal for both anesthetics. In the surgeries with osteotomy, the comparison between A200 and B200 showed statistically significant differences in the diastolic (64 mm Hg and 68 mm Hg, respectively, P = .001) and mean arterial pressure (86 mm Hg and 89 mm Hg, respectively, P = .031) when data from all the surgical phases were pooled. Additionally, the mouth opening at the suture removal was statistically different for A200 and B200 solutions (91.90% +/- 3.00% and 88.57% +/- 2.38% of the preoperative measure, respectively) when surgeries required bone removal (P < .05). Conclusions: In comparison with 0.5% bupivacaine, 4% articaine (both with 1: 200,000 epinephrine) provided a shorter time to onset and comparable hemostasis and postoperative pain control with a shorter duration of soft tissue anesthesia in lower third molar removal.
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Background Distraction osteogenesis (DO) is a method of producing new bone directly from the osteotomy site by gradual traction of the divided bone fragments. Aim The purpose of the present study was to evaluate histomorphometrically whether acute DO would constitute a viable alternative to the conventional continuous distraction treatment and also to verify the capacity of a recombinant human BMP (rhBMP-2) associated with monoolein gel to stimulate bone formation in the acute distraction process. Materials and methods Forty-eight Wistar rats were assigned to three groups: Group 1, treated at a conventional continuous distraction rate (0.5 mm/day), Group 2, treated with acute distraction of 2.5 mm at the time of the surgical procedure, and Group 3, subjected to acute distraction associated with rhBMP-2. The animals from each experimental group were killed at the end of the second or fourth post-operative weeks and the volume fraction of newly formed bone trabeculae was estimated in histological images by a differential point-counting method. Results The results showed that after 2 and 4 weeks, bone volumes in the rhBMP-2 group were significantly higher than in the other groups (P < 0.05), but no significant difference was observed in the volume fraction of newly formed bone between the continuous and acute DO groups. Conclusion In conclusion, the study indicates that rhBMP-2 can enhance the bone formation at acute DO, which may potentially reduce the treatment period and complications related to the distraction procedure. To cite this article:Issa JPM, do Nascimento C, Lamano T, Iyomasa MM, Sebald W, de Albuquerque Jr RF. Effect of recombinant human bone morphogenetic protein-2 on bone formation in the acute distraction osteogenesis of rat mandibles.Clin. Oral Impl. Res. 20, 2009; 1286-1292.doi: 10.1111/j.1600-0501.2009.01799.x.
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Articulatory patterns and nasal resonance were assessed before and 6 months after orthognathic reconstruction surgery in five patients with dentofacial deformities. Perceptual and physiological assessments showed disorders of nasality and articulatory function preoperatively, two patients being hyponasal, and one hypernasal. Four patients had mild articulatory deficits, and four had reduced maximal lip or tongue pressures. Operation resulted in different patterns of change. Nasality deteriorated in three patients and articulatory precision and intelligibility improved in only one patient and showed no change in the other four. Operation improved interlabial pressures in three patients, while its impact on tongue pressures varied, being improved in one case, deteriorating in one, and remaining unchanged in the other three. The variability in the results highlights the need for routine assessment of speech and resonance before and after orthognathic reconstruction. (C) 2002 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Science Ltd. All rights reserved.
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Purpose: Because it is believed that bone may respond to exercise differently at different ages, we compared bone responses in immature and mature rats after 12 wk of treadmill running. Methods: Twenty-two immature (5-wk-old) and 21 mature (17-wk-old) female Sprague Dawley rats were randomized into a running (trained, N = 10 immature, 9 mature) or a control group (controls, N 12 immature, 12 mature) before sacrifice 12 wk later. Rats ran on a treadmill five times per week for 60-70 min at speeds up to 26 m.min(-1). Both at baseline and after intervention, we measured total body, lumbar spine, and proximal femoral bone mineral, as well as total body soft tissue composition using dual-energy x-ray absorptiometry (DXA) in vivo. After sacrificing the animals, we measured dynamic and static histomorphometry and three-point bending strength of the tibia. Results: Running training was associated with greater differences in tibial subperiosteal area, cortical cross-sectional area, peak load, stiffness, and moment of inertia in immature and mature rats (P < 0.05). The trained rats had greater periosteal bone formation rates (P < 0.01) than controls, but there was no difference in tibial trabecular bone histomorphometry. Similar running-related gains were seen in DXA lumbar spine area (P = 0.04) and bone mineral content (BMC; P = 0.03) at both ages. For total body bone area and BMC, the immature trained group increased significantly compared with controls (P < 0.05), whereas the mature trained group gained less than did controls (P < 0.01). Conclusion: In this in vivo model, where a similar physical training program was performed by immature and mature female rats, we demonstrated that both age groups were sensitive to loading and that bone strength gains appeared to result more from changes in bone geometry than from improved material properties.
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Esta dissertação parte das bases da crítica de Gadamer à consciência estética desde o contexto de fundamentação das ciências naturais e decorrente estabelecimento das ciências humanas. Considerando o posicionamento contrário de Gadamer quanto ao predomínio dos métodos das ciências naturais em todos os âmbitos da experiência humana no mundo, nosso esforço será no sentido de abordar a compreensão da experiência estética. Neste sentido, nos voltaremos para a aisthesis com vistas a caminhar focando na problemática em torno da arte a partir de Platão e Aristóteles, culminando no estabelecimento da estética como campo específico do saber filosófico no pensamento iluminista de Baumgarten. Destarte, o presente escrito voltar-se-á para as bases da consciência estética que se encontram na subjetivação decorrente dos efeitos do pensamento crítico de Kant. Com isso, abordaremos as perspectivas de Gadamer com vistas a liberar a experiência da arte do âmbito da consciência estética, o que, segundo este filósofo, pode ocorrer a partir da assunção de um tipo de experiência que pode ser tomado como verdade mesmo não estando restrito aos métodos das ciências naturais. Partindo desta prerrogativa,Gadamer lança mão da noção de jogo como experiência fora da centralidade subjetiva. Com o redirecionamento da experiência, o fenômeno artístico pode aparecer como parte constitutiva da experiência existencial humana sem estar restrito às faculdades subjetivas.
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O Acidente Vascular Cerebral (AVC) é uma das principais causas de prejuízos ao sistema neuromuscular. Dispositivos Robóticos vêm sendo amplamente desenvolvidos e estudados com a finalidade de serem utilizados na assistência à marcha e para o treinamento da marcha durante a reabilitação. O objetivo deste trabalho é avaliar a marcha assistida pelo AROW (Assistive Robotic Walker) em indivíduos hemiparéticos pós-AVC, através da análise de sinais de acelerometria e sinais mioelétricos de superfície (sEMG) provenientes dos músculos vasto medial (VM), bíceps femoral (BF), tibial anterior (TA) e gastrocnêmio medial (GM), e também utilizando os métodos de avaliação GAS (Goal Attainment Scaling) e SUS (System Usability Scale). Nove indivíduos hemiparéticos participaram dos testes. A velocidade da marcha foi reduzida com o uso do AROW e, consequentemente, houve algumas alterações na duração das fases da marcha, por exemplo, uma maior duração da fase de apoio (p = 0,0174). O padrão de ativação muscular para o grupo analisado não apresentou diferença estatisticamente significativa (início da ativação VM: p= 0,4999; término da ativação VM: p= 0,5647; início BF: p= 0,1186; término BF: p= 0,7823; início TA: p= 0,5833; término TA: p= 0,8393; início GM: p= 0,6077; término GM: p= 0,1429). Entretanto, avaliando o padrão de ativação muscular individualmente, podem-se notar algumas alterações benéficas, por exemplo, redução da coativação dos músculos tibial anterior e gastrocnêmio medial. Os resultados das avaliações através do GAS (54,8) e SUS (81,4) sobre o uso do AROW mostraram boa aceitação pelos usuários, e os objetivos esperados durante o uso do andador foram atingidos. A adaptação rápida, facilidade de utilização e sentimento de segurança ao usar o dispositivo são pontos positivos obtidos com o uso do AROW.
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Lê-se o Banquete de Platão como um diálogo sobre o amor e duas funções da boca: a pulsional (comer) e a verbal (falar)