Orientador: Regina Paolucci El Dib / Coorientador: Amélia Kamegasawa / Banca: Eliane Jorge / Banca: Tais W. / Resumo: Introdução: A córnea é uma túnica transparente responsável por 60% do poder refrativo do olho. Segundo a Organização Mundial da Saúde (OMS), doenças que afetam a transparência da córnea são responsáveis por 5,1% do total de cerca de 45 milhões de cegos. O Brasil é o país que mais realiza transplantes de córnea na América Latina. A taxa de perda endotelial gira em torno de 0,6/ano em pessoas normais. Essa taxa é acelerada após cirurgias oculares ou glaucoma. Essa perda, após o transplante penetrante devido trauma inicial, reação imune, glaucoma secundário, interação celular entre o doador e receptor, seria de 7,8%/ano nos primeiros cinco anos e 4,2%/ano após 10 anos. Alguns estudos sugerem perda endotelial maior no Descemet's stripping automated endothelial keratoplasty/Ceratoplastia endothelial automatizada "stripping" de Descemet (DSAEK) (34% após seis meses) do que no transplante penetrante (11%) enquanto outros mostram que a perda endotelial após um ano é maior no transplante penetrante. A sobrevida do enxerto em ambas as técnicas foram semelhantes e o resultado óptico superior na técnica DSAEK. Há quase um século o transplante penetrante tem sido a técnica cirúrgica de escolha no manejo de alterações corneais. Apesar das vantagens de procedimentos lamelares, como menor risco de complicações intra-oculares e rejeição do enxerto, o transplante penetrante ainda mostra ser a técnica de preferência da maioria dos transplantadores mundiais. Entretanto, nos últimos anos, várias técnicas de ceratoplastia lamelar têm sido desenvolvidas, modificadas ou melhoradas, principalmente técnicas para substituição da porção posterior para correção da ceratopatia bolhosa. A escolha de ceratopatia bolhosa pós facectomia foi por esta ser a principal causa de transplantes relacionados a disfunções endoteliais. Objetivo: Avaliar a eficá cia e a seguranç a d a ceratoplastia endotelial quando... / Abstract: Introduction: The cornea is a transparent organ responsible for 60% of the refractive power of the eye. According to the World Health Organization (WHO), diseases affecting the transparency of the cornea are responsible for 5.1% of total of about 45 million blind. Brazil is the country that performs corneal transplants in Latin America. Endothelial loss rate is around 0.6 / year in normal people. This rate is accelerated after eye surgery or glaucoma. This loss after penetrating keratoplasty because initial trauma, immune reaction, secondary glaucoma, cell interaction between donor and recipient, it would be 7.8% / year in the first five years and 4.2% / year after 10 years. Some studies suggest a greater endothelial cell loss in DSAEK (34% after six months) than in penetrating keratoplasty (11%) while others show that endothelial cell loss after one year is higher in penetrating keratoplasty. Graft survival in both techniques were similar and higher optical result in DSAEK technique. For nearly a century the penetrating keratoplasty has been surgical technique of choice in the management of corneal changes. Despite the advantages of lamellar procedures such as intraocular lower risk of complications and graft rejection further shows penetrating keratoplasty is the preferred technique of most of the world transplant. However, in recent years, several lamellar keratoplasty techniques have been developed, modified or improved, especially techniques for replacement of the posterior portion for correction of bullous keratopathy. Objective: To evaluate the efficacy and safety in endothelial keratoplasty when compared to penetrating keratoplasty for the improvement of visual acuity in aphakic and pseudophakic bullous keratopathy. Methods: Systematic review of randomized controlled trials (RCTs) and / or quasirandomized studies that assessed endothelial keratoplasty versus penetrating keratoplasty in adults diagnosed with aphakic or ... / Mestre

INTRODUÇÃO: O significado clínico das vasculites, lesões isquêmicas, efeito Quilty e da presença de eosinófilos em biópsias endomiocardicas de receptores de transplante cardíaco com rejeições leves não foi ainda estabelecido. OBJETIVOS: Verificar se estes achados histológicos encontrados nas biópsias endomiocardicas (eosinófilos, vasculites, efeito Quilty e lesões isquêmicas) são capazes de predizer rejeição aguda do enxerto acompanhada ou não de grave comprometimento hemodinâmico e morte por rejeição aguda. MÉTODOS: Foram reavaliadas 939 biópsias endomiocardicas consecutivas classificadas como OR ou 1R pela de 2005 da Nomenclatura da Sociedade Internacional de Transplante de Coração e Pulmão e dividimos estas em dois grupos (1) Biópsias preditoras: aquelas que precederam rejeição aguda, rejeição aguda associada à grave comprometimento hemodinâmico ou morte e (2) Biópsias não preditoras aquelas que não precederam eventos clínicos. Comparamos a ocorrência dos seguintes achados histológicos: vasculites, lesões isquêmicas, efeito Quilty e eosinófilos por análise uni e multivariada entre os grupos. RESULTADOS: Após análise estatística verificou-se que a presença de vasculite intensa e de eosinófilos como maiores preditores tanto para rejeição aguda futura, apresentando respectivamente as seguintes razões de chance: 10,60 (IC95%: 3,62 31,06. p<0,001) e 6,26 (IC95%:3,16 12,43. p< 0,001) , quanto para rejeição aguda associada á grave comprometimento hemodinâmico, que para este desfecho clínico apresentaram respectivamente as seguintes razões de chance 7,52 (IC95%: 1,45-38,93. p=0,016) e 6,61 (IC95%: 2,38 18,31. p< 0,001), e também para morte em decorrência a rejeição aguda com as respectivas razões de chance: 11,20 (IC95%: 3,53 36,17. p < 0, 001) e 14,50 (IC95%: 2,19 36,17. p = 0,006). CONCLUSÕES: Vasculites intensas e eosinófilos em biópsias do miocárdio são os principais fatores preditores de rejeição aguda, rejeição aguda associada à grave comprometimento hemodinâmico e morte pós - transplante cardíaco / INTRODUCTION: The clinical meaning of vasculitis, ischemic lesions, Quilty effect and the presence of eosinophils in endomyocardial biopsies of transplant recipients with mild rejections have not been established yet. OBJECTIVES: Verify if these histological findings (eosinophils, vasculitis, Quilty effect and ischemic lesions), whose clinical meaning remains unknown so far, are able to predict acute rejection of the transplanted organ, accompanied or not by severe hemodynamic compromise and death due to acute rejection. METHODS: We reevaluated 939 consecutive endomyocardial biopsies classified as 0R or 1R, according to the nomenclature that the International Society for Heart and Lung Transplantation established in 2005. We divided these biopsies in 2 groups, as they follow: (1) Predictor biopsies, which are preceded by acute rejection, acute rejection associated to severe hemodynamic compromise or death and (2) Non-predictor biopsies that did not precede any clinical events. We compared the occurrence of the histological findings studied (eosinophils, vasculitis, Quilty effect and ischemic lesions) through univariate and multivariate analysis among the groups. RESULTS: After an appropriate statistical analysis, the result obtained was the presence of intense vasculitis and eosinophils as the greatest predictors of future acute rejection, presenting the respective odds ratio: 10,60 (IC95%: 3,62 31,06. p<0,001) and 6,26 (IC95%:3,16 12,43. p< 0,001), as well as acute rejection associated to severe hemodynamic compromise, which presented the respective odds ratio for this clinical outcome: 7,52 (IC95%: 1,45-38,93. p=0,016) and 6,61 (IC95%: 2,38 18,31. p< 0,001) and death due to acute rejection, presenting the respective odds ratio: 11,20 (IC95%: 3,53 36,17. p < 0, 001) and 14,50 (IC95%: 2,19 36,17. p = 0,006). CONCLUSIONS: Intense vasculitis and eosinophils in myocardial biopsies post-cardiac transplantation are the chief factors that can predict acute rejection, acute rejection associated to severe hemodynamic compromise or death

Steady state crossflow microfiltration (CMF) is an important and often necessary means for varying sized particle separation. It has been widely used in both industrial and biomedical processes, including a wearable water removal device intended to maintain end stage renal disease (ESRD) patients euvolemic. For kidney replacement therapies, there are few options available. Kidney transplantation still represents the optimal treatment for ESRD patients, even though it often requires daily post-transplant medication including immunosuppressant drugs to avoid rejection of the transplanted organ. The transplanted kidney itself has an average lifespan of only 10 years. The biggest engineering contribution to the cited problem was made about 60 years ago with the invention of dialysis machines (or some variation thereof). Dialysis still represents the optimal and most widely used therapeutic approach to renal replacement during long waits on a transplant list. The present-day dialysis system is bulky, totally mechanical, and extracorporeal, leading to a widely used therapy that is only effective in extracting water and toxins out of the blood-stream, but still with major drawbacks (i.e. intermittent treatments, 5-hours thrice-weekly, and forcing clinic-centered therapy) that are permanently costly. These drawbacks pose a major impediment to rehabilitation or any other lifestyle activity such as working or studying. Of all the vital organs, the kidney is both the most subtle in its homeostatic action and the most complex in terms of the structures it uses to accomplish its action. This thesis proposes a single facet of the multiple complexity of this vital organ: filtration. To that effect, CMF of blood suspensions through a microsieve were studied. Experiments, reported here, have correlated macroscopic measurements - filtration rates, transmembrane pressures (TMP), shear rates - during filtration through a photolithographically pored semiconductor membrane with direct observation of erythrocyte behavior at the filtering surface. Erythrocytes, the preponderant particles in blood, are believed to dominate filtration resistance. At low filtration rates (low TMP), erythrocytes roll along the filter, but at higher rates (higher TMP), there is an increasing probability of their sticking to the sieve. The design of membrane separation processes requires quantitative expressions relating the separation performance to material properties. The factors controlling the performance of CMF have been and continue to be extensively reviewed. There have been a number of influential approaches in CMF. Most have been based on the rate limiting effects of the concentration polarization of rejectate at the sieving surface. Various empirical and intuitive models exist which have been critically assessed in terms of their predictive capability and applicability to CMF from a microfluidic channel. Chapter 1 summarizes this assessment. Chapter 2 takes a closer look at how erythrocytes behave in a microfiltration environment. Maximum steady-state filtration flux has been observed to be a function of wall shear rate, as predicted by any conventional cross-flow filtration theory, but to show weak dependence on erythrocyte concentration, contrary to theory based on convective diffusion. Flux is known to be directly proportional to the TMP; however, since the pressure drop across a channel decreases along the direction of flow, TMP must modulate along the channel (highest at the leading edge of the membrane and lowest at the trailing edge). As a consequence, an area of stuck particles growing from the inlet (regimen of high TMP) has been observed, leading to a “fouling cascade.” Post-filtration scanning electron micrographs revealed significant capture and deformation of erythrocytes in all filter pores in the range 0.25 to 2 m diameter. This was then found to form a self-assembled partially complete monolayer. Filtration rates through these filters were reported and a largely unrecognized mechanism was proposed, which allows for stable filtration in the presence of substantial cell layering. Chapter 3 proposes a microfiltration model that pertains to non-deformable particles that are large enough to intrude significantly into the shear layer of a microchannel. A stable, stationary multilayer of particles was studied, whose thickness is shear-limited. The structure and parameters in that limit of steady filtration in this environment was then identified. A steady cake-layer thickness was observed and because of the simple geometry afforded by uniform spheres, the force balance, cake resistance, and filtration rate were derived from first principles. The good fit of the data to the proposed mechanism, provides a firm basis for the semi-quantitative analysis of the behavior of more complex suspensions. Finally, in Chapter 4, a design methodology was imposed to maintain the TMP constant throughout the whole sieving surface by introducing a flow chamber beneath and parallel to the sieve’s main flow. Co-current filtration was found to allow the TMP to remain stable along the membrane surface, enabling the entire sieve to perform optimally, and thus allowing greater stable filtration rates to be achieved. Co-current flow conditions allowed for twice as much filtration flux compared to a conventional CMF modality.

No description available.

Introduction: NKT cells are categorised as borderline between NK and T cells, sharing phenotypic and functional characteristics of both cells, demonstrating their capacity to contritube to both pro- or anti-inflammatory processes. However, the role of these cells among lung transplant recipients remains largely unknown. The aim of this study was to determine the role of NKT cells following lung transplantation. Methods: NKT cells were quantified and characterised according to markers of: activation (CD107a, CD161, NKG2D) and immunomodulation (CD200 and CD200R) in peripheral blood and BALs. NKT cell numbers and phenotypes were correlated to clinical variables: immunosuppression, acute rejection, acute infections (viral, bacterial and fungal), bronchiolitis obliterans syndrome (BOS grade), lung function, and demographic variables. Interactions between NKT cells and the transplanted lung were linked by determining the relative expression of immunomodulatory ligand CD200 in lung biopsies. In vitro models were employed to determine the role of NKT cells to acute lung injury, either alone or in combination with cells of the mononuclear phagocyte system (MPS). Results: Higher numbers of immunomodulatory NKT cells (CD200+ and CD200R+) were found as lung function decreased. Data from peripheral blood indicates that recipients whose donors or themselves had been exposed to CMV infection demonstrated increased numbers of NKT cells. Patients with active EBV infections demonstrated higher NKT cell numbers expressing CD200 and CD200R. Data from BALs, indicates that patients with active fungal infections present higher immunomodulatory (CD200R) NKT cells and lower cytotoxicity marker (CD107a). In peripheral blood, lung recipients demonstrated higher NKT cell numbers compared to healthy volunteers. However, the lower relative mean expression of functional markers in the lung transplant group suggests that cells are less active. In vitro cultures with immunosuppressants demonstrated that cell cycle inhibitors (MMF and AZA) and corticosteroids (Prednisolone) are likely to inhibit NKT cell proliferation, while calcineurin inhibitors (Cyclosporine A and Tacrolimus) decrease the relative mean expression of activation markers. Clinical observations indicate that higher doses of Azathioprine may correlate with increased NKT cell numbers and the relative expression of CD200 and CD200R. However, under these conditions the relative expression of activation marker NKG2D decreases. In vitro data from the acute injury model indicates that NKT cells are capable to migrate into the injured lung and become activated following transmigration which is facilitated by the presence of monocytes. We also observed the interaction of NKT cells with endothelial cells, monocytes and macrophages. Also, the relative mean expression of CD200 and CD200R increased at the capillary layer, regardless of injury while upregulation of activation markers (CD107a, CD161 and NKG2D) was found at the capillary layer, following injury. In contrast, the alveolar layer demonstrated a decrease in both activation and immunomodulatory markers, following acute injury. Conclusions: Despite immunosuppression, NKT cells remain present in peripheral blood and BAL following lung transplantation. NKT cell proliferation is likely to be reduced by effect of cell cycle inhibitors, while calcineurin inhibitors exert an immunomodulatory effect. Our data indicates that NKT cells can participate in inflammatory and immunomodulatory events at the alveolar bilayer. Their capacity to infiltrate the lungs was assisted by cells of the mononuclear phagocyte system (MPS), which play an important role in antigen presentation and modulation of acute injury. Further research is needed to elucidate the signals and mechanisms occurring between NKT and MPS interactions and the outcomes these populations drive in acute lung injury.

Polyglutamine (polyQ) diseases are a group of progressive neurodegenerative disorders, which are caused by the expansion of an existing glutamine-coding CAG repeat in the coding region of disease genes. The cell nucleus is a major site of polyQ toxicity, and gene transcription is compromised in polyQ-induced neurodegeneration. Understanding the nuclear translocation of mutant polyQ proteins is therefore crucial to unfold the complex pathogenic mechanisms that underlie the neuronal toxicity of polyQ disease. The polyQ domain is the only common sequence found among different mutant disease proteins. Nuclear transport signals have been identified in some, but not all, polyQ disease proteins. The detection of those mutant polyQ proteins that carry no classical nuclear transport signal, but not their normal counterparts, in the cell nucleus suggests the existence of uncharacterized nuclear transport signals in mutant polyQ proteins. Thus, the objective of the present study is to elucidate the nuclear transport pathway(s) adopted by an expanded polyQ domain and determine its correlation with polyQ toxicity. / Through a series of genetic and biochemical studies in cell culture, mouse and transgenic Drosophila models, exportin-1 was found to modulate the nucleocytoplasmic localization of mutant polyQ protein and its toxicity. Further, mutant polyQ protein was also demonstrated to be a novel transport substrate of exportin-1. By promoting the nuclear export of mutant polyQ protein, exportin-1 suppressed polyQ toxicity by reducing the interference of mutant polyQ protein on gene transcription. It was found that the protein level of exportin-1 diminished in the normal ageing process, which would result in an exaggeration of nuclear mutant polyQ toxicity. Thus, the age-dependent decline of exportin-1 level, at least in part, accounts for the progressive degeneration observed in polyQ patients. Results obtained from this project first demonstrated that expanded polyQ domain is a nuclear export signal, and further provided mechanistic explanation of how protein nuclear transport receptors modulate polyQ toxicity. / Chan, Wing Man. / Source: Dissertation Abstracts International, Volume: 71-01, Section: B, page: 0113. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 189-203). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.

O presente estudo avaliou uma casuística constituída por 144 transplantes dentários autógenos realizados em 128 pacientes, submetidos a controles periódicos de 6 meses a 23 anos. O objetivo do trabalho foi avaliar a influência de fatores clínicos e radiográficos no índice de sucesso dos transplantes realizados. Clinicamente avaliou-se a alteração na coloração dentária, vitalidade pulpar, comprometimento periodontal, tipo dentário transplantado e sítio receptor. Radiograficamente foram avaliados a presença ou não de reabsorção radicular, anquilose dento-alveolar, alterações no compartimento pulpar, complementação do desenvolvimento radicular, presença de periapicopatia persistente e relação coroa/raiz. Os dados foram coletados, analisados e submetidos a cálculos estatísticos pertinentes. As reabsorções dentárias, a anquilose dentoalveolar, a proporção coroa/raiz, a presença de periapicopatia persistente, o desenvolvimento de bolsa periodontal profunda e a mobilidade dentária destacaram-se de forma significante estatisticamente P<0,05. O tipo dentário doador, o sítio receptor, as alterações na coloração dentária e o desenvolvimento radicular na época da cirurgia do transplante não alcançaram índices de significância relacionados ao insucesso dos casos. A presença de processos esclerosantes pulpares mostrou-se comum aos transplantes bem sucedidos de dentes com rizogênese incompleta. Estes achados contribuem para o desenvolvimento de um protocolo terapêutico bem fundamentado. / The present study examined a sample consisting of 144 autogenous dental transplants performed in 128 patients, subjected to periodic follow-up from 6 months to 23 years. The objective was to evaluate the influence of clinical and radiographic factors in the success rate of the performed transplants. Clinical evaluation aimed the change in tooth color, pulpal vitality, periodontal involvement, transplanted tooth type and recipient site. Radiographic evaluation aimed the presence or absence of root resorption, ankylosis, pulpal changes, complementation of the root development, presence of persistent periapical lesions and crown-root ratio. The data were collected, analyzed and submitted to the relevant statistical calculations. Tooth resorptions, ankylosis, crown to root proportion, presence of persistent periapical lesions, development of periodontal pocket depth and tooth mobility was highlighted as statistically significant P <0.05. The donor tooth type, the receptor site, changes in tooth color and root development at the time of the transplant surgery did not reach levels of significance related to the failure of the cases. The presence of pulpal sclerosis processes shown to be common to successful transplantation of teeth with incomplete root formation. These findings contribute to the development of a reliable therapeutic protocol.

O objetivo deste estudo foi avaliar o efeito do laser em baixa intensidade na cicatrização de defeitos ósseos preenchidos com vidro bioativo (VB), em animais. Foi criado um defeito ósseo de tamanho crítico (DTC) com 5 mm de diâmetro na calvária de 60 ratos machos adultos (Rattus novergicus, albinos, Winstar), pesando entre 250g e 300g. Os animais foram divididos aleatoriamente em 6 grupos (n=10), sendo: 1) Grupo C (controle), 2) Grupo L (laser), 3) Grupo OA (osso autógeno), 4) Grupo OAL (osso autógeno + laser), 5) Grupo VB (vidro bioativo), 6) Grupo VBL (vidro bioativo + laser). Os animais foram submetidos a eutanásia após 30 dias. As áreas de osso neoformado (AON) e as áreas de partículas remanescentes de vidro bioativo (APR) foram calculados em relação à área total (AT), em porcentagem. Para análise estatística dos dados utilizou-se o teste paramétrico ANOVA, seguido pelo teste Tukey (p>0,05). A maior média de AON foi encontrada no grupo L (47,67 +8,66), seguido pelos grupos OAL (30,98 +16,59)e VBL (31,13 + 16,98). Houve diferença estatisticamente significante em relação ao AON entre o grupo C e os demais grupos com exceção da comparação com o grupo VB (Teste Tukey, p>0,05); entre os grupos L e VB quanto aos valores de AON (Teste Tukey, p>0,05). Não houve diferença estatisticamente significante dos valores de AON entre o grupo OA e os demais grupos estudados (Teste Tukey, p>0,05), entre o grupo OAL e os grupos VB e VBL quanto aos valores de AON (Teste Tukey, p>0,05) e entre os grupos VB e VBL (Teste Tuckey, p>0,05). A maior média de APR foi encontrada no grupo VB (25,15 + 4,82), seguido pelo grupo VBL (17,06 +9,01). Não houve diferença estatisticamente significante entre os grupos (teste t, p>0,05). O laser em baixa intensidade, com o protocolo de aplicação utilizado, não contribuiu para o aumento da área de neoformação óssea dos sítios preenchidos com vidro bioativo, no período avaliado. / The objective of this study was to evaluate the effect of low-level lasers on the healing of bone defects grafted with bioactive glass (VB) in animals. A bone defect of critical size with 5mm in diameter was made in the skullcap of 60 male adult rats (Rattus novergicus, albinos, Winstar), weighing between 250g and 300g. The rats were divided randomly into 6 groups (n=10). Those being: 1) Group C (control); 2) Group L (laser); 3) Group OA (autogenous bone); 4) Group OAL (autogenous bone + Laser); 5) Group VB (bioactive glass); 6) Group VBL (bioactive glass + laser). The rats were euthanized after 30 days. The areas of new bone formation (AON) and the areas of remaining particles of bioactive glass (APR) were calculated in relation to the total area by percentage. For statistical analysis of the data, the parametric ANOVA rest followed by the Tukey test (p>0,05) was used. The highest average AON was found in group L (47,67 + 8,66), followed by groups OAL (30,98 + 16,59) and VBL (31,13 + 16,98). There was a statistically significant difference regarding in AON between Group C and the other groups with the exception of comparison with Group VB (Tukey Test, p>0,05). There was also a statistically significant difference between the L and VB groups regarding the AON value (Tukey Test, p>0,05). There was no statistically significant difference of AON values between group OA and the other groups studied (Tukey Test, p>0,05); between group OAL and the groups VB and VBL regarding the AON value (Tukey Test, p>0,05); and between the VB and VBL groups (Tukey Test, p>0,05). The highest average of APR was found in group VB (25,15 + 4,82), followed by group VBL (17,06 + 9,01).There was no statistically significant difference between groups (teste t, p>0,05). The low-level laser, with the application protocol used, did not contribute to an increase in the new bone formation area of the sites grafted with bioactive glass in the assessed period of time.

O propósito deste estudo foi avaliar, histologicamente, o efeito do laser de baixa intensidade na cicatrização óssea de defeitos de tamanho crítico (DTC- 5mm) criados cirurgicamente em calvárias de ratos, quando associado ou não ao osso bovino inorgânico (Bio-Oss®). 60 ratos machos (Rattusnorvegicus, albinus, Wistar) foram divididos em 6 grupos: C (controle), L (Laser de Baixa Intensidade - GaAlAs, 730nm, 100mW, 6J, 210J/cm2), AO (Osso Autógeno) OAL (Osso Autógeno + Laser de Baixa Intensidade), BO (Osso Bovino Inorgânico), BOL (Osso Bovino Inorgânico + Laser de Baixa Intensidade) . Os animais foram submetidos à eutanásia após 30 dias. A quantidade de osso neoformado e a área de partícula remanescente dos materiais implantados foram calculadas como porcentagem da área do defeito original. Os dados foram submetidos à análise estatística (Teste de Kruskal - Wallis, Teste de Dunn; p<0,05). Os grupos irradiados com laser de baixa intensidade, L (47,67% ± 8,66%), OAL (39,15% ± 16,72%) e BOL (48,57% ± 28,22%) apresentaram maior área de neoformação óssea que os grupos C (9,96% ± 4,50%), OA (30,98% ± 16,59%) e BO (11,36% ± 7,89%) que não foram irradiados. Além disso, foram significativamente melhores que o Grupo C. Dentro dos limites deste estudo, conclui-se que o laser acelerou o processo de neoformação óssea e de reabsorção das partículas dos materiais de enxertia, podendo ser considerado uma modalidade terapêutica interessante a ser associada com biomateriais em cirurgias ósseas reconstrutivas. / This study histologically evaluated the effect of low level laser on the bone healing of critical size defects (CSD- 5mm) surgically created in rat calvaria, associated or not with inorganic bovine bone (Bio-Oss®). Sixty male rats (Rattus norvegicus, albinus, Wistar) were divided in 6 groups: C (control), L (low level laser - GaAlAs, 730nm, 100mW, 6J, 210J/cm2), AO (autogenous bone) OAL (autogenous bone + low level laser), BO (inorganic bovine bone), BOL (inorganic bovine bone + low level laser). The animals were killed after 30 days. The quantity of newly formed bone and area of remaining particles of the implanted materials were calculated as percentages of the original defect area. Data were statistically analyzed (Kruskal Wallis test, Dunn test; p<0.05). The groups irradiated with low level laser, L (47.67% ± 8.66%), OAL (39.15% ± 16.72%) and BOL (48.57% ± 28.22%) presented greater area of new bone formation than the groups C (9.96% ± 4.50%), OA (30.98% ± 16.59%) and BO (11.36% ± 7.89%), which were not irradiated. Also, they were significantly better than group C. within the limits of this study, it was concluded that the laser accelerated the new bone formation and resorption of particles of graft materials, thus it may be considered an interesting therapeutic option for association with biomaterials in reconstructive bone surgeries.

No description available.