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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Microtopographic enhancement of land-based wastewater treatment

Tyrrell, Sean R. January 2016 (has links)
There is a regulatory tension within wastewater treatment, between the requirement to meet tightening consents and the need to reduce the carbon footprint of treatment processes. With 75% of wastewater treatment works serving populations of less than 2,000, low-energy tertiary treatment options suitable to small rural works need to be developed. One option that lends itself particularly well to small works is land-based wastewater treatment (LBWWT). The aim of this research was to evaluate the role of LBWWT in the UK water industry and investigate the impact ridge-and-furrow enhanced microtopography (MT) may have upon a particular type of LBWWT - slow-rate (SR) infiltration. This was achieved through meeting three objectives. Firstly, the use of LBWWT was reviewed and assessed. Secondly, the impact of ridge-and-furrow enhanced MT upon the vegetation diversity and nutrient removal of a SR- LBWWT was established by means of a three year field trial. Finally, the cost- effectiveness of SR-LBWWT and the impact of ridging and furrow irrigation upon cost-effectiveness were evaluated using Cost-Effectiveness Analysis (CEA). The first objective comprised of a review of the historical and current use of LBWWT, a review of the relevant changing legislation to identify what may be required of LBWWT and an assessment of LBWWT’s potential to meet these requirements. The result of the evaluation found that, based upon the literature, SR-LBWWT is ‘fit-for-purpose’ as tertiary treatment for small treatment works. To meet the second objective, a SR-LBWWT system trial was established at a small wastewater treatment works in Knowle, Hampshire. The trial consisted of three clay-loam grass plots irrigated with secondary treated effluent. There were two configurations of trial plot - flat and ridge-and-furrowed. Effluent (sub- surface soil water) nutrient concentrations were monitored as was vegetation diversity. In addition a number of physical, hydrological and biogeochemical parameters were monitored and hydrological modelling carried out. Mean nutrient removal performances of 90% for ammonia, 72% for nitrate, and 91% for phosphate were observed with the ridge-and-furrowed plot. Ridging and furrow irrigation was found to not have a significantly detrimental effect upon the trial plots’ removal performance for ammonia, nitrate or phosphate. Extrapolation modelling suggested, however, that this would not be the case for LBWWT systems on predominantly clay or sand soils. Ridging and furrow irrigation was found to have a statistically significant positive effect upon the vegetation diversity of the LBWWT trial plots; with mean final year Shannon-Wiener values of 0.96 and 0.69, for the ridge-and-furrowed and non-ridged plots, respectively. For the final objective, analysis found that SR-LBWWT are cost-effective when compared to horizontal sub-surface flow constructed wetlands (HSSFCW), an established low-energy treatment option. Mean cost-effectiveness ratio values of £208.5 and £262.7 per % effectiveness were observed for LBWWT and HSSFCW, respectively. Following the field trial CEA was extended to include ridge-and-furrowed SR-LBWWT systems. This found that ridging and furrow irrigation improves the cost-effectiveness of SR-LBWWT serving small populations, reducing the mid cost-effectiveness ratio to £193 per % effectiveness. This is a result of the cost-reducing effect of ridge-and-furrowing over laser-level grading; and based upon the findings of the trial that ridging and furrow irrigation can be achieved (in clay-loam soil slow-rate systems) without significant detriment to the water treatment effectiveness of LBWWT. The main conclusions of this thesis are: that SR-LBWWT has a role to play in the UK water industry, as tertiary treatment for small wastewater treatment works. That SR-LBWWT is cost-effective in relation to HSSFCW. That ridging and furrow irrigation increases that cost-effectiveness by reducing the construction and operational costs. That ridging and furrow irrigation can be employed without significant detriment to a SR-LBWWT system’s water treatment performance. And finally, that ridging and furrow irrigation can have a positive impact upon the establishment vegetation diversity of a SR-LBWWT system.
222

An Application of Ridge Regression to Educational Research

Amos, Nancy Notley 12 1900 (has links)
Behavioral data are frequently plagued with highly intercorrelated variables. Collinearity is an indication of insufficient information in the model or in the data. It, therefore, contributes to the unreliability of the estimated coefficients. One result of collinearity is that regression weights derived in one sample may lead to poor prediction in another model. One technique which was developed to deal with highly intercorrelated independent variables is ridge regression. It was first proposed by Hoerl and Kennard in 1970 as a method which would allow the data analyst to both stabilize his estimates and improve upon his squared error loss. The problem of this study was the application of ridge regression in the analysis of data resulting from educational research.
223

Site structure and chronology of 36 Lake Mojave and Pinto assemblages from two large multicomponent sites in the central Mojave Desert, southern California

Jenkins, Dennis L. 06 1900 (has links)
xxviii, 463 p. : ill., maps. A print copy of this title is available through the UO Libraries under the call number: KNIGHT F868.M65 J45 1991 / The environmental context and chronology of the transition from Early Holocene Lake Mojave to Middle Holocene Pinto cultural complexes of the southern California deserts has long been debated. This dissertation re-examines that debate, based on excavations at two major sites, and a rethinking of our most basic assumptions concerning culture change, cultural ecology, site formation processes, and dating techniques. Archaeological data recovered from two Lake Mojave/Pinto sites at Fort Irwin, in the Central Mojave Desert, were analyzed in order to track chronologically sensitive shifts in Lake Mojave-Pinto artifact assemblages through time. The archaeological assemblages recovered from Rogers Ridge and the Henwood sites were carefully analyzed into 36 depositional/analytical components for this task. Defining and chronologically ordering these assemblages required systematic consideration of artifact distributions and the development and application of 3 obsidian hydration rates based on associations with twelve 14C dates. The analysis shows that the Pinto Complex occurred in three phases. Phase I, ca. 8,200 to 7,500 BP, is marked by the addition of Pinto points to the Lake Mojave assemblage and a continuation of the basic Lake Mojave settlementsubsistence patterns. Phase II, 7,500 to 5,000 BP, is marked by the gradual disappearance of Lake Mojave points from the archaeological assemblages. Dramatic decreases in assemblage size and increases in assemblage diversity mark changing logistical strategies to infrequent and specialized site use. Phase III, 5,000 to 4,000 BP, is marked by a strong predominance of Pinto points and slightly larger assemblages. Patterns of variation among assemblages suggest that logistical strategies continued to emphasize infrequent and specialized site useage. The link between environmental change and shifting settlement-subsistence strategies was apparently relatively direct during the Pinto period, Environmental changes during the Early Holocene (11,000 to 8,000 BP) Mojave Desert led to subsistence stress among populations of the Pinto Complex. Cultural adjustments resulted in smaller human populations moving through larger home territories. It is suggested that critical thresholds in communication and mating networks were crossed which resulted in the collapse of social systems in the Mojave Desert about 7,000 BP. / Committee in charge: C. Melvin Aikens, Ann Simonds, Don E. Dumond, and William Loy
224

Enxerto autógeno para aumento em espessura e ou altura do processo ósseo alveolar, transtornos de técnica cirúrgica, complicações e sobrevivência dos implantes

Moraes Júnior, Edgard Franco [UNESP] January 2002 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2002Bitstream added on 2014-06-13T20:21:54Z : No. of bitstreams: 1 moraesjunior_ef_dr_araca.pdf: 1027137 bytes, checksum: 69155df278e66cc86de2444a36139fb6 (MD5) / Foi realizado um estudo retrospectivo para avaliar os resultados da reconstrução do processo alveolar intensamente reabsorvido com diferentes tipos de enxerto ósseo autógeno associados à instalação de implantes simultâneos e mediatos (após 4 meses da instalação do enxerto) realizados no período de 4 anos e 6 meses. Foram selecionados para este estudo 84 pacientes, submetidos à reconstrução de defeitos ósseos dos maxilares, com enxertos ósseos do mento, linha oblíqua da mandíbula, crista ilíaca anterior e calota craniana, com um total de 346 implantes instalados, sendo que, 257 destes implantes encontravam-se, com as próteses implantossuportadas instaladas, e distribuídos em 40 implantes simultâneos e 217 mediatos. Desta forma, foram avaliadas os transtornos de técnica cirúrgica e as complicações relacionadas com as áreas receptoras, bem como a taxa de sobrevivência dos implantes. De acordo com os resultados obtidos, dentre alguns dos transtornos de técnica cirúrgica e complicações estavam a redução da quantidade de mucosa ceratinizada na cortical vestibular e conseqüente perda da profundidade de sulco, assim como, exposição parcial do enxerto, contaminação do enxerto, entre outras complicações verificadas. A taxa de sobrevivência, obtida para os implantes simultâneos e mediatos instalados, foi de 94,55%. Quando a taxa de sobrevivência foi avaliada individualmente para cada grupo, no caso dos implantes simultâneos foi encontrado um resultado de 97,50%, enquanto que para os implantes mediatos obteve-se um resultado de 94,10%%. Portanto com este estudo, conclui-se que dos transtornos de técnica cirúrgica com maior ocorrência estava a redução da quantidade de mucosa ceratinizada sobre a crista do rebordo, complicações como exposição parcial do enxerto entre outras, que as áreas doadoras intrabucais oferecem vantagem... / A retrospective study was carried out in order to evaluate the outcomes of the reconstruction of the severely resorbed alveolar ridge through different types of autogenous bone grafts associated to the placement of simultaneous and delayed implants (4 months after the bone graft procedure) accomplished during a period of 4 years and 6 months. A total of 84 patients were selected for the present study, which were submitted to reconstruction of the bone defects of the jaws by means of bone grafts from the chin, external oblique ridge, anterior iliac crest, cranial vault, adding up to 346 implants, from which 257 (40 simultaneous and 217 delayed implants), with the installed implant-supported prostheses. The evaluation concerned of the overturn of surgical technique and complications related to the receptor sites, as well as the survival rate of the implants. The results indicated occurrence of the overturn of surgical technique and complications such as reduction in the amount of keratinized mucosa over the buccal cortical plate with consequent decrease in vestibular depth, as well as partial exposure of the graft, contamination of the graft, and others. The survival rate for both simultaneous and delayed implants was 94.55%. Regarding the individual evaluation of each group, the simultaneous implants demonstrated a survival rate of 97.50% in relation to 94.10% for the delayed implants. The most frequent of the overturn of surgical technique were reduction in the amount of keratinized mucosa over the alveolar ridge, complications as partial exhibition of the graft among others, better performance of the intraoral donor sites in relation to the extraoral sites, positive association between implant failures and iliac crest grafts, besides significantly worse outcomes for the female subjects in relation to the males. Better results were observed for the simultaneous implants, what is in disagreement with previous studies.
225

Avaliação histológica e histométrica do enxerto ósseo autógeno de calota craniana em reconstrução de maxila atrófica em humanos

Coradazzi, Luis Francisco [UNESP] 28 April 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-04-28Bitstream added on 2014-06-13T21:04:27Z : No. of bitstreams: 1 coradazzi_lf_dr_araca.pdf: 554297 bytes, checksum: c5cfb463f29a39c5571e8140faed3c14 (MD5) / Devido a sua micro-arquitetura de composição cortical, baixo padrão de reabsorção e a possibilidade de obtenção de grande quantidade de tecido ósseo, o osso da calota craniana se destaca como uma das principais áreas doadoras para grandes reconstruções de maxilas atróficas para posterior reabilitação com próteses implanto-suportadas. O objetivo desse estudo foi de observar e mensurar, através de avaliação histológica e histométrica, os eventos celulares que ocorrem na interface de união do enxerto onlay de osso parietal na maxila de 10 pacientes, após um período de 6 meses de incorporação. As biópsias foram realizadas no momento da instalação dos implantes osseointegráveis. A área de contato ósseo representou 78,75% e a de contato conjuntivo em fase de remodelação 21,25%. A região de união conjuntiva entre o enxerto ósseo com o leito receptor apresentou osso neoformado (41,26%), medula (36,06%), tecido osteóide (15,86%) e tecido conjuntivo (6,80%). Em todas as amostras houve uma boa incorporação do enxerto ao leito receptor, com atividade osteogênica ativa e ausência de células inflamatórias. / Because of its micro-architecture of cortical composition, low standard of absorption and the possibility to obtain large amount of bone tissue, the calvarial bone is highlighted as a good donor area for large reconstructions of atrophic jaw for subsequent rehabilitation with implant-supported prosthesis. The aim of this study was to observe and measure through histological and histometric evaluation, the cellular events that occur at the interface of union from onlay parietal bone graft on the maxilla of 10 patients, after a period of 6 months of incorporation. The biopsies were performed at the time of installation of osseointegrated implants. The bone contact area represented 78.75% and connective contact 21.25%. The region of connective union between the bone graft to the maxillae presented new bone formation (41.26%), marrow bone (36.06%), osteoid tissue (15.86%) and connective tissue (6.80%). All samples had good graft incorporation to the receptor bed with osteogenic activity and absence of inflammatory cells.
226

Surface Response to Slip Along a Propagating Blind Thrust Fault, Wheeler Ridge, California

January 2015 (has links)
abstract: Understanding topography developed above an active blind thrust fault is critical to quantifying the along-strike variability of the timing, magnitude, and rate of fault slip at depth. Hillslope and fluvial processes respond to growing topography such that the existing landscape is an indicator of constructional and destruction processes. Light detection and ranging (lidar) data provide a necessary tool for fine-scale quantitative understanding of the topography to understand the tectonic evolution of blind thrust faulting. In this thesis, lidar topographic data collected in 2014 are applied to a well-studied laterally propagating anticline developed above a blind thrust fault in order to assess the geomorphic response of along-strike variations in tectonic deformation. Wheeler Ridge is an asymmetric east-propagating anticline (10 km axis, 330 m topographic relief) above a north-vergent blind thrust fault at the northern front of the Transverse Ranges, Southern San Joaquin Valley, California. Wheeler Ridge is part of a thrust system initiating in the late Miocene and is known to have significant historic earthquakes occur (e.g., 1952 Mw 7.3 Kern County earthquake). Analysis of the lidar data enables quantitative assessment of four key geomorphic relationships that may be indicative of relative variation in local rock uplift. First, I observe remnant landforms in the youngest, easternmost section of Wheeler Ridge that indicate the erosional history of older deposits to the west. Second, I examine the central portion of Wheeler Ridge where drainages and hillslopes are closely tied to uplift rates. Third, I observe the major wind gap within which a series of knickpoints are aligned at a similar elevation and tie into the local depositional and uplift history. Finally, I survey the western section and specifically, the fold backlimb where high-resolution topography and field mapping indicate long ridgelines that may preserve the uplifted and tilted alluvial fan morphology. I address changing landforms along the fold axis to test whether backlimb interfluves are paleosurfaces or the result of post-tectonic erosional hillslope processes. This work will be paired with future geochronology to update the ages of uplifted alluvial fan deposits and better constrain the timing of along-strike uplift of Wheeler Ridge. / Dissertation/Thesis / Masters Thesis Geological Sciences 2015
227

Tufas calcárias da Serra da Bodoquena, MS / \"Calcareous tufa from Bodoquena\'s Ridge, MS\"

Emiliano Castro de Oliveira 13 April 2009 (has links)
Aflorando abundantemente nas drenagens da Serra da Bodoquena, região sudoeste do Estado de Mato Grosso do Sul, os depósitos de tufas calcárias, descritos como a porção superior da Formação Xaraiés, representam o mais notável depósito do tipo no Brasil, devido à variedade de formas. Sendo a maior atração do pólo eco-turístico de Bonito, MS, as tufas calcárias apresentam-se sob formas de barragens, cachoeiras e depósitos de micritos inconsolidados, que por sua vez geram as piscinas naturais e quedas dágua tão procuradas pelos turistas. Mesmo com tamanha importância, tal rocha não havia recebido um estudo aprofundando, que contemplasse sedimentologia, estratigrafia e geomorfologia. Através de criteriosa revisão bibliográfica, trabalhos em campo e análises laboratoriais, pôde-se obter um panorama da Formação Xaraiés na Serra da Bodoquena. Nesta região, observa-se que a formação, assentada diretamente sobre os calcários e dolomitos do Grupo Corumbá, sendo composta por um nível basal de calcretes, de tipo pedogenético e freático, sobreposto por um pacote de tufas micríticas (micrito inconsolidado), com grande quantidade de gastrópodes, distribuídos amplamente e aflorando em todas as planícies da região. Por fim temos os afloramentos de tufas calcárias do tipo fitohermal, compondo barragens e cachoeiras nas drenagens locais. Acredita-se que a deposição dos micritos ocorreu em ambiente lacustre, o que permitiu um depósito amplo e homogêneo, que posteriormente, em clima úmido, serviu de área fonte, juntamente com os carbonatos do Grupo Corumbá, para a geração das tufas fitohermais. A correlação estratigráfica dos depósitos de tufas calcárias estudados apontam para dois períodos de clima semi-árido a árido no Holoceno, que permitiram a formação e a alteração (calcretização) de depósitos, refletido na base da Formação Xaraiés, e o período climático recente, úmido, a formação das tufas fitohermais, no topo da formação. A ocorrência de lentes micríticas no sul do Pantanal pode significar que esta região também esteve exposta às dinâmicas climáticas vistas na Serra da Bodoquena. Estas constatações demonstram a alta variação climática da região, representada por depósitos que são pequenos e frágeis, mas dotados de significados genéticos indubitáveis. / Crop out abundantly in the Bodoquena Ridge drainages, southwest of Mato Grosso do Sul (MS) state, deposits of calcareous tufa were described as the top portion of Xaraiés Formation, representing the most notable deposit of this type in Brazil, due to the variety of forms. As the greatest attractiveness of Bonito, MS, an eco-tourism center, the calcareous tufa were presented in form of dams, waterfalls and deposits of micritic sediments, which generate natural pools and waterfalls so looked by tourists. Even with such importance, this region had not received a deep study, with sedimentology, stratigraphy and geomorphology approach. An accurate bibliographic review was done, and with field work and laboratory analyzes this work could obtain a panorama of the Xaraiés Formation in Bodoquena Ridge. In this region, can be noted that Xaraiés Formation goes directly over the limestone and dolomite of the Corumbá Group, and were composed by a basal layer of pedogenetic/groundwater calcrete, superimposed by a package of micritic sediments (micritic tufa), with a large amount of gastropods, which were widely distributed, cropping out in all plains of the region. Finally, we have the occurrences of calcareous tufa, fitohermal type, drawing dams and waterfalls in the regional drainages. It has believed that the deposition of lacustrine micritic sediments have occurred in an environment which were enabled a broad and homogeneous deposits. Subsequently, in a moister climate these sediments served as a source area, together with the limestone of the Corumbá Group, for the generation of fitohermal tufa. The stratigraphic correlation of the studied calcareous tufa deposits point to two periods of semi-arid/arid climate in Holocene, which allowed the calcretization. Those were reflected on the bottom of the Xaraiés Formation, and a recent wet climatic period, represented by the fitohermal tufa at the top of the formation. The occurrence of micritic lens in the southern Pantanal may mean that this region has also been exposed to the weather dynamics viewed in the Bodoquena Ridge. These findings show the high variation of climate in this region, represented by deposits, which are small and fragile, but gifted with unquestionable genetic meanings.
228

Avaliação histológica e histométrica do enxerto ósseo autógeno de calota craniana em reconstrução de maxila atrófica em humanos /

Coradazzi, Luis Francisco. January 2008 (has links)
Orientador: Idelmo Rangel Garcia Júnior / Banca: Osvaldo Magro Filho / Banca: Paulo Sérgio Perri de Carvalho / Banca: Daniela Ponzoni / Banca: Luís Antônio Violin Pereira / Resumo: Devido a sua micro-arquitetura de composição cortical, baixo padrão de reabsorção e a possibilidade de obtenção de grande quantidade de tecido ósseo, o osso da calota craniana se destaca como uma das principais áreas doadoras para grandes reconstruções de maxilas atróficas para posterior reabilitação com próteses implanto-suportadas. O objetivo desse estudo foi de observar e mensurar, através de avaliação histológica e histométrica, os eventos celulares que ocorrem na interface de união do enxerto onlay de osso parietal na maxila de 10 pacientes, após um período de 6 meses de incorporação. As biópsias foram realizadas no momento da instalação dos implantes osseointegráveis. A área de contato ósseo representou 78,75% e a de contato conjuntivo em fase de remodelação 21,25%. A região de união conjuntiva entre o enxerto ósseo com o leito receptor apresentou osso neoformado (41,26%), medula (36,06%), tecido osteóide (15,86%) e tecido conjuntivo (6,80%). Em todas as amostras houve uma boa incorporação do enxerto ao leito receptor, com atividade osteogênica ativa e ausência de células inflamatórias. / Abstract: Because of its micro-architecture of cortical composition, low standard of absorption and the possibility to obtain large amount of bone tissue, the calvarial bone is highlighted as a good donor area for large reconstructions of atrophic jaw for subsequent rehabilitation with implant-supported prosthesis. The aim of this study was to observe and measure through histological and histometric evaluation, the cellular events that occur at the interface of union from onlay parietal bone graft on the maxilla of 10 patients, after a period of 6 months of incorporation. The biopsies were performed at the time of installation of osseointegrated implants. The bone contact area represented 78.75% and connective contact 21.25%. The region of connective union between the bone graft to the maxillae presented new bone formation (41.26%), marrow bone (36.06%), osteoid tissue (15.86%) and connective tissue (6.80%). All samples had good graft incorporation to the receptor bed with osteogenic activity and absence of inflammatory cells. / Doutor
229

Avaliação histológica e microtomográfica comparativa entre o aloenxerto ósseo liofilizado e o aloenxerto ósseo congelado para preenchimento na elevação do assoalho de seio maxilar / Histological and microtomografic assessment between lyophilized and fresh-frozen allogenic bone grafts for sinus lifting : Randomized Controlled clinical Trial

Marcello Roberto Manzi 15 September 2016 (has links)
O aloenxerto ósseo desmineralizado irradiado (ALD) e o aloenxerto ósseo congelado mineralizado (ACM) são alternativas ao osso autógeno para o aumento do rebordo ósseo alveolar. Individualmente, já foram testados quanto a eficiência, de certa forma, comparável aos autógenos e suas vantagens sobre eles. Entretanto, não há estudos padronizados comparando o desempenho clínico entre esses dois tipos de aloenxertos, quando utilizados em região de maxila atrófica para instalação e implantes. O objetivo deste estudo foi realizar um ensaio clínico randomizado controlado que envolve a elevação bilateral do seio maxilar empregando o osso alógeno liofilizado desmineralizado irradiado (ALD) ou o osso alógeno congelado mineralizado (ACM) e verificar comparativamente os desfechos clínicos para estabilidade de implantes, quantidade e qualidade de neoformação óssea. Dez pacientes foram submetidos a cirurgia de elevação do seio maxilar bilateral na qual foi utilizado um dos tipos de aloenxerto, de forma randômica em um dos lados. Seis a nove meses após o aumento do rebordo ósseo, no momento da instalação de implantes osseointegrados, foram obtidas amostras ósseas por meio de trefina de 2x10mm para análises microtomográficas e histológicas. A estabilidade dos implantes foi aferida por frequência de ressonância em dois momentos, imediato e após 6 meses da instalação dos implantes. Os resultados mostraram aumento do rebordo, radiograficamente detectável em todos os pacientes e grupos. Os implantes osseointegrados, inseridos em enxertos ACM, apresentaram melhor estabilidade primária, embora o acréscimo de estabilidade tenha sido mais significativo no ALD. As análises microtomográficas e histológicas revelaram mais formação óssea de melhor qualidade nos ALD do que nos ACM. Não houve resposta a corpo estranho para nenhum dos tipos de aloenxertos. Notou-se mais quantidade de material remanescente para ACM do que para ALD. Concluímos que os aloenxertos liofilizados desmineralizados irradiados (ALD) apresentaram melhor desempenho quanto aos parâmetros estudados. / Demineralized bone irradiated allograft (DFDBA) and fresh- frozen (FF) are alternative grafts to autogenous bone in alveolar ridge augmentation. Individually, these allografts have been tested for their efficiency, in a way comparable to autogenous, and so their advantages over autogenous grafts. However, there are no standardized clinical studies comparing the clinical and histological performance between these two allografts in atrophic maxilla bone augmentation for implants instalment. The aim of this study was to perform a randomized controlled clinical trial involving bilateral sinus floor elevation employing demineralized freeze-dried irradiated allograft (DFDBA) or fresh-frozen (FF) and to compare clinical and histological outcomes for stability of implants, quantity and quality of bone formation. Ten patients underwent bilateral maxillary sinus lifting surgery in which side was randomly used one of those allografts for alveolar ridge augmentation. Six to nine months after grafting, at the time of dental implants instalment, trephine 2x10mm bone core biopsies were obtained to micro computed tomographic and histological analyses. The stability of the implants was measured by resonance frequency in two stages, immediately and 6 months after implants installation. Results showed that there was an increase, radiographically detectable, in all patients and groups. The dental implants inserted in FF grafts showed better primary stability but implant stability, lately, increased significantly in DFDBA. Micro tomographic and histological analyses revealed that bone formation amount and quality was superior in DFDBA than in FF. There was no foreign body response for any of the allografts. There was a greater amount of persisting graft-materialin FF than in DFDBA. We conclude that demineralized freeze-dried irradiated allograft (DFDBA) presented a superior performance than mineralized FF.
230

Análise histomorfométrica da perfuração do leito receptor no processo de neoformação óssea do enxerto autógeno onlay corticomedular: estudo em humanos

Gusmão, Pricila da Silva 06 September 2016 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-01-12T12:08:07Z No. of bitstreams: 1 priciladasilvagusmao.pdf: 1850463 bytes, checksum: 28df311f56f4e6ce80747dff41cee7cb (MD5) / Approved for entry into archive by Diamantino Mayra (mayra.diamantino@ufjf.edu.br) on 2017-01-31T11:17:27Z (GMT) No. of bitstreams: 1 priciladasilvagusmao.pdf: 1850463 bytes, checksum: 28df311f56f4e6ce80747dff41cee7cb (MD5) / Made available in DSpace on 2017-01-31T11:17:27Z (GMT). No. of bitstreams: 1 priciladasilvagusmao.pdf: 1850463 bytes, checksum: 28df311f56f4e6ce80747dff41cee7cb (MD5) Previous issue date: 2016-09-06 / O objetivo dessa pesquisa foi avaliar, por histomorfometria, em humanos, se existe influência do método de perfurar o leito receptor no processo de neoformação óssea do enxerto autógeno onlay corticomedular. Após exames clínicos e radiográficos, foram selecionados nas clínicas da Faculdade de Odontologia da Universidade Federal de Juiz de Fora, oito pacientes (2 homens e 6 mulheres; média de 56,9 anos), que apresentavam rebordos alveolares atróficos, em região de maxila, com indicação de enxerto ósseo autógeno onlay, sendo a área doadora de eleição a sínfise. Os pacientes passaram por dois procedimentos cirúrgicos, sendo a primeira fase de enxertia e a segunda, após seis meses, coleta de material para análise histomorfométrica e instalação dos implantes. Cada paciente participou, simultaneamente, dos dois grupos de estudo, ou seja, grupo teste (GT) em que o leito receptor foi perfurado e grupo controle (GC), em que o leito receptor não recebeu perfuração para receber o enxerto em bloco. Os resultados demonstraram que as características microscópicas de ambos os grupos evidenciaram presença de neoformação óssea, observando-se que houve diferença estatística entre os grupos (p = 0,046), em que uma média de 5,74% (± 1,27) foi atribuída a GT e 3,68 (± 1,82), a GC. Concluiu-se que, no grupo de pacientes analisados, a perfuração do leito receptor demonstrou influência no processo de neoformação óssea do enxerto autógeno onlay corticomedular. / The objective of this research was to evaluate, histomorphometry, in humans, if there is influence of the method of perforate the recipient bed in the bone formation process autogenous corticomedullar onlay graft. After clinical and radiographic examinations were selected at the clinics of the Faculty of Dentistry, Federal University of Juiz de Fora, eight patients (2 men and 6 women, mean 56.9 years), with no physiological or organic changes, which had ridges atrophic in Jaw region, indicating autogenous bone graft onlay, and the donor area of the symphysis election. The patients underwent two surgical procedures, the first phase of grafting and the second time after six months, collecting material for histomorphometric analysis and implant placement. Each patient participated simultaneously in the two study groups, namely, test group (TG) in which the recipient bed has been perforated and control group (CG), the receiver bed has not received perforation for insertion of the graft block. The results showed that the microscopic characteristics of both groups showed presence of new bone formation, noting that there was no statistical difference between the groups (p = 0.046), in which an average of 5.74% (± 1.27) was assigned GT and 3.68 (± 1.82), the GC. It was concluded that, in the group of patients studied, the drilling of the recipient bed demonstrated influence on bone formation process of autogenous onlay graft corticomedullar.

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