Dissertations / Theses: 'Bone-grafting'

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Herbert, Amy Angharad. "Bone grafting : tissue treatment and osseointegration." Thesis, Cardiff University, 2004. http://orca.cf.ac.uk/55547/.

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Bone grafts fill skeletal defects and provide a structure upon which new bone can be deposited. There is no standard method of storing bone prior to grafting, the three main storage regimes being stored fresh frozen at -80°C, gamma irradiated or freeze dried. The initial aim of this project was to determine how osteoblastic cells behaved when exposed to bone treated in the above ways. It was found that sterilisation of bone with gamma irradiation caused cell death in a number of the cells that came into contact with it. Therefore the use of gamma irradiation for grafting is contraindicated, a similar observation was observed for freeze-dried bone whereas cells grew and differentiated on fresh frozen tissue. The second aim of this study was to develop a system whereby bone marrow cells could be expanded in culture and retain their osteogenic potential so that they would be suitable for either coating a bone graft (thus increasing the rate of osseointegration of the graft) or used alone to treat small bone defects. Rodent bone marrow was used in a variety of cultures and bone formation was induced by either BGJ-b medium or ECCM (Endothelial cell conditioned medium). Control cultures were grown in alpha modification minimum essential medium. ECCM was overall found to produce a greater number of cells at the end of the incubation periods studied than BGJ-b medium. BGJ-b medium preferentially selected mineralization over cell proliferation under all of the culture conditions studied (monolayers, collagen gels and organ cultures). This medium would be best suited to forming small pieces of bone rapidly from bone marrow, to fill small bone defects such as those seen in the dental field. ECCM produced large numbers of osteogenic cells, which could potentially be used to coat large bone grafts.

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Mak, Siu Yan. "Mechanical factors influencing impaction bone grafting." Thesis, University of Bath, 2007. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486839.

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Impaction grafting for bone stock loss in revision total hip arthroI;>lasty has been used for over a decade. This technique typically involves the insertion of a cemented highly polished stem into impacted morsellised allograft bone. The aim is to compensate for the bone stock loss after failed primary hip arthroplasty and to provide a mechanical and biological scaffold for mechanical support and bone remodelling. The primary objective of this study is to quantify and optimise the graft properties so as to provide maximum supportive forces to the stem, and, at' the same time, to minimise the amount of per.:operative and post-operative femoral fractures. More than 60 parameters that could affect the mechanical properties of graft have been identified. Porcine bone from femoral heads was used in the study which was primarily divided into two parts: fundamental studies of the graft material, and in-vitro mechanical testing to replicate the clinical application of impaction bone grafting. Various techniques of graft preparation including defatting of the graft were investigated. A die-plunger was employed to perform uni-axial compressive testing on the graft at varying strain rates. It was found that defatted' graft demonstrated higher stiffness. Higher rates of loading resulted in increases in stiffness, hoop strain, axial force and Poisson's ratio. Preloading of the graft provided more predictable mechanical characteristics. Cyclic compressive testing showed th~t individual graft particles fractured during compression. In addition, it was found that the graft demonstrated increased viscoelastic properties at higher strain rates. In-vitro mechanical testing was also performed to compare the level of mechanical stability of a cemented polished stem with a larger uncemented polished stem. Composite femora were '' used for this comparison. It was found that the cemented stem showed higher mechanical stability in terms of the level of micromotion and migration, and uncemented stem failed in a catastrophic manner. The study provided information on how various factors contributed to the mechanical behaviour of bone graft and identified parameters that should be used when in-vitro testing of bone graft materials for use in impaction grafting.

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Twitty, Anne. "The expression of tissue inhibitor of metalloproteinase during the early stages of bone graft healing." Thesis, Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21804023.

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Dattani, Rupen. "Femoral impaction grafting : using bone graft substitutes." Thesis, University College London (University of London), 2008. http://discovery.ucl.ac.uk/1444261/.

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Background: Femoral impaction allografting to reconstitute bone loss during revision hip surgery has shown excellent results. However, limitations with the use of allografts have warranted research to investigate if bone graft substitutes could be a suitable alternative to replace or augment allograft in impaction grafting.;Aims and Methods: The objectives of this thesis were to assess if: The use of hydroxyapatite (HA) in various combinations with allograft will be biologically effective and functionally stable using a cemented impaction grafting technique in an ovine hemiarthroplasty model. The different treatment groups were compared by measuring the ground reaction forces and new bone formation. The addition of mesenchymal stem cells (MSCs) to allograft, HA or an allograft:HA mixture enhances the amount of new bone formation compared with impaction of the scaffold alone in an ovine metaphyseal femoral bone defect model. The architecture of the HA scaffold influences bone formation in an extra-skeletal sheep model.;Results: HA: allograft mixture of up to 90:10 demonstrated similar functional stability and amount of new bone formation as a 50:50 mixture. Addition of MSCs to allograft or a 50:50 allograft:HA mixture enhances the amount of new bone formation compared with unimpacted constructs. HA either alone or combined with MSCs induces bone growth only when constructed in block form and not in identical porous granular form.;Conclusion: HA is a suitable bone substitute to augment allograft and may be replace bone graft completely in impaction grafting of a femoral component. This has important clinical implications as HA is readily available, easy to use in surgery and not associated with the adverse effects encountered with allografts. The use of MSCs in the treatment of osteolysis holds great potential but further work is required to assess if this technology is transferable to humans.

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黃美娟 and May-kuen Alice Wong. "Bone induction of demineralized intramembranous and endochondral bone matrices." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B3197305X.

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Wong, May-kuen Alice. "Bone induction of demineralized intramembranous and endochondral bone matrices." View the Table of Contents & Abstract, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21872752.

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Thorén, Klas. "Lipid-extracted bone grafts." Lund : Dept. of Orthopedics, University Hospital, Lund University, 1994. http://catalog.hathitrust.org/api/volumes/oclc/39676934.html.

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Lie, Ken Jie Ronny Ket Phoei. "The healing of composite endochondral bone grafts a qualitative and quantitative analysis /." Hong Kong : Faculty of Dentistry, The University of Hong Kong, 1995. http://sunzi.lib.hku.hk/HKUTO/record/B38628120.

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李國培 and Ken Jie Ronny Ket Phoei Lie. "The healing of composite endochondral bone grafts: a qualitative and quantitative analysis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B38628120.

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McNamara, Iain Robert. "Characterisation of the mechanical response of morcellised bone graft and bone graft substitutes for impaction grafting." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608923.

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Wong, Wing-kit Ricky, and 黃永傑. "The effect of demineralized intramembranous bone matrix on the healingof autogenous bone grafts." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31973061.

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Gan, Jade Ho Yue School of Biomedical Engineering UNSW. "Characterisation of bone defect models in immunodeficient animals." Awarded by:University of New South Wales. School of Biomedical Engineering, 2005. http://handle.unsw.edu.au/1959.4/22429.

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Bone defects resulting from non-unions, fractures, significant revision joint replacements, tumour resection and osteolysis present a clinical problem. While autografts are considered the gold standard, ubiquitous use of this reparative technique is limited by graft supply and site morbidity. Recent progresses in tissue engineering using stem cells, bone enhancing molecules and gene therapy have provided more hypotheses for bone defect treatment. In vivo assessment to test these hypotheses requires animal models to mimic human conditions. Immunodeficient or nude animals have the advantage of hosting materials from human and other xenographic origins without immuno-intolerance or rejection. A thorough understanding of the biology in nude animals is vital for the further advancement of connective tissue healing and regeneration strategies. Nude mice are excellent xenographic hosts for in- vivo characterisation and provide a reproducible animal source. The immune deficiencies of nude compared to normal animals may however, influence bone healing and need to be addressed. This dissertation (a) investigated potential bone defect models in nude mice and nude rats (b) incorporated the selected bone defect model to evaluate the effect of T cell deficiency and age on bone defect healing in nude animals (c) determined the feasibility of a critical size defect (CSD) in nude mice. A distal-femur-condylar-defect (DFCD) model was successfully performed in nude mice and rats. The model was found to have some advantages as a bone defect model: (1) located at a weight-bearing skeletal site (2) no requirements for an internal or external fixator (3) does not obstruct or limit mobility (4) location is not in close proximity to any major organs such as the brain (5) easy identification of surface anatomy (6) defect size is standardised and reproducible (7) does not require lengthy and complicated surgery and (8) cost effective. This dissertation confirmed that bone healing in nude mice is similar to that of normal immunocompetent mice. Absence of T lymphocytes did not delay or inhibit bone repair. Use of older nude mice did not seem to affect the healing rate, in contrast to older normal mice, which showed delay in bone healing in the initial phase. Establishment of critical sized defects in mice at a weight-bearing location was not feasible due to the robust healing of murine. This dissertation recommends that the DFCD model could be utilized for the assessment of xenogenic materials at early time point.

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Wong, Wing-kit Ricky. "The effect of demineralized intramembranous bone matrix on the healing of autogenous bone grafts." Click to view the E-thesis via HKUTO, 1999. http://sunzi.lib.hku.hk/hkuto/record/B31973061.

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Gundle, Roger. "Microscopical and biochemical studies of mineralised matrix production by bone-derived cells." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282203.

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Muller, Sébastien. "Mechanical and adaptive behaviour of bone in relation to hip replacement : A study of bone remodelling and bone grafting." Doctoral thesis, Norwegian University of Science and Technology, Department of Structural Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2067.

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This thesis, consisting of an introduction and four separate papers, gathers considerations on bone behaviour in relation to total hip replacement. Aspects related to primary hip replacement, principally adaptive bone remodelling, are addressed in Paper I from a clinical point of view and in Paper II from a mechanical point of view. Morsellised bone applied in secondary hip replacement is studied in Paper III, where its recoil is modelled as viscoelastic, while Paper IV questions the validity of a solid model for this material.

The relationship between preoperative bone stock and relative postoperative change of bone amount was investigated in Paper I. Younger patients with custom uncemented femoral implants who had high preoperative bone stock had more bone loss than those with low preoperative bone stock. This unexpected result around the hip is nevertheless an accepted result in knee replacement. Also a new graphic interpretation of the paired variations of bone mineral density and projected bone area showed that bone tends to remodel after surgery to reach a lower density and a higher volume.

The main purpose of Paper II was to connect mechanical stimulus to the remodelling observed in the same patients as in Paper I. Bone remodelling was simulated individually and compared with the clinical measurements in the corresponding patient. An additional modelling of a hypothesised fading memory of the bone was implemented to an established set of equations connecting mechanical stimulus to remodelling. Comparisons at a global level of simulated and clinical results showed that simulations have a good predictive value but are not quantitatively correct prior to statistical processing. The observed discrepancy suggested an improvement of the material modelling.

The recoil behaviour of morsellised bone is of great clinical relevance for the primary stability of revision implants. The aim of Paper III was threefold: derive from experiments clinically relevant material parameters, use these to discriminate the effect of pre-treatment of the bone grafts on their recoil properties, and compare these outcomes to loading properties. The experimental unloading was a model using a linear viscoelastic solid model from which three parameters were derived describing the swelling retardation, the swelling speed and the amount of swelling. They allowed the identification of significant effects of water content and particle size on the recoil of morsellised bone. Two of the parameters correlated to loading properties.

The protocol used in Paper III investigates only part of the behaviour of morsellised bone. A different geometry and load modus was studied in Paper IV. Impacted morsellised bone in a cavity mimicking the femoral canal was loaded axially and with torsion. The experiment was modelled with finite elements using the same material modelling as in Paper III, a linear viscoelastic solid model. Though the simulation captured the gross features of the response of bone grafts to loading, it did not achieve displacements as large as in the experiments. This suggested that the pulverulent behaviour of morsellised bone dominated in this load case, allowing it to flow under load, which indicates that fluid viscoelasticity could be a better model for bone grafts.

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Farnsworth, Kelly Dee Jr. "Evaluation of Two Techniques of Cancellous Bone Grafting of Experimental Subchondral Bone Cysts in the Medial Femoral Condyles of Horses." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36870.

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Cylindric (10 mm diameter X 15 mm deep) osteochondral defects were created in the medial femoral condyles of 5 horses to mimic clinical cases of subchondral bone cysts after debridement. The defects were created with either a standard square ended drill bit or a compaction drill bit. The compaction drill bit compresses bone laterally and distally creating a dense wall and floor. Twelve-mm sternal cancellous cylinders were compressed to 9.25 mm and inserted into the femoral defects where they were presumed to expand and tighten the fit. The end result was sternal cancellous bone that exactly fit the femoral defects. Fluorochrome bone labels were used to confirm the origin of bone present in the defects at necropsy, which was performed after 6 months. Successful graft incorporation occurred in 3 of the compacted and 2 of the noncompacted defects. The surfaces of the successful cancellous bone grafts contained predominately fibrocartilage. The unsuccessful noncompacted defects expanded laterally and deeply into the parent bone epiphysis while the unsuccessful compacted defects remained confined to the originally created size.
Master of Science

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Abbah, Sunny Akogwu. "Towards an injectable bone graft substitute evaluation of sodium alginate microcapsules for bone tissue engineering /." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B39329951.

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Hui, Hin-ming. "The morbidity of anterior iliac bone harvesting for maxillofacial grafting procedures." Click to view the E-thesis via HKUTO, 1998. http://sunzi.lib.hku.hk/HKUTO/record/B38628211.

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Monaghan, Pierre. "Histological analysis of bovine bone grafting using the rat tibia model." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=55515.

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Experimental investigations were carried out concerning the use of bovine bone (Unilab Surgibone) grafted in the tibiae of rats. The first experiment evaluated tissue response of bovine bone as an inlay graft and the second experiment as an onlay graft. Histological and morphometric analyses were performed in order to obtain baseline data on tissue response for future experiments using titanium implants with bovine bone grafts in this model. Light microscopy demonstrated rapid incorporation of the inlay graft by new bone, whereas, the onlay graft was mainly encapsulated by fibrous tissue. However, a residual increase in the thickness of the outer cortex of the tibiae was observed with onlay graft. From the results of this study it appeared that Unilab Surgibone was biocompatible and did not induce a foreign body reaction. Future investigations using titanium implants in combination with the bovine bone grafts appears to be possible especially if an inlay/onlay design is attempted.

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Orellana, Bryan R. "BIOERODIBLE CALCIUM SULFATE BONE GRAFTING SUBSTITUTES WITH TAILORED DRUG DELIVERY CAPABILITIES." UKnowledge, 2014. http://uknowledge.uky.edu/cbme_etds/18.

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Bone regeneration or augmentation is often required prior to or concomitant with implant placement. With the limitations of many existing technologies, a biologically compatible synthetic bone grafting substitute that is osteogenic, bioerodible, and provides spacing-making functionality while acting as a drug delivery vehicle for bioactive molecules could provide an alternative to ‘gold standard’ techniques. In the first part of this work, calcium sulfate (CS) space-making synthetic bone grafts with uniformly embedded poly(β-amino ester) (PBAE) biodegradable hydrogel particles was developed to allow controlled release of bioactive agents. The embedded gel particles’ influence on the physical and chemical characteristics of CS was tested. Namely, the compressive strength and modulus, dissolution, and morphology, were studied. All CS samples dissolved via zero-order surface erosion consistent to one another. Compression testing concluded that the amount, but not size, of embedded gel particles significantly decreased (up to 75%) the overall mechanical strength of the composite. Release studies were conducted to explore this system’s ability to deliver a broad range of drug types and sizes. Lysozyme (model protein for larger growth factors like bone morphogenic protein [BMP]) was loaded into PBAE particles embedded in CS matrix. The release of simvastatin, a small molecule drug capable of up regulating BMP production, was also examined. The release of both lysozyme and simvastatin was governed by dissolution of CS. The second part of this work proposed a bilayered CS implant. The physical and chemical properties were characterized similarly to the CS composites above. Release kinetics of directly loaded simvastatin in either the shell, core, or both were investigated. A sequential release of simvastatin was witnessed giving foresight of the composite’s tunability. The sequential release of an antibacterial, metronidazole, loaded into poly(lactic-co-glycolic acid) (PLGA) particles embedded into the shell along with directly loaded simvastatin either in the shell, core, or both layers was also observed. Through controlled release of bioactive agents, as well as a tunable layered geometry, CS-based implants have the potential to be optimized in order to help streamline the steps required for the healing and regeneration of compromised bone tissue.

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許顯名 and Hin-ming Hui. "The morbidity of anterior iliac bone harvesting for maxillofacial grafting procedures." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B38628211.

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Patel, Nelesh. "In vivo assessment of hydroxyapatite and substituted apatites for bone grafting." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615793.

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Crout, Richard Morrow. "Timing of alveolar cleft bone grafting in maxillary alveolar cleft defects." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1446.

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Matsushita, Naoya, Atsushi Kouyama, and Toshiki Iwase. "COMPLETE BONE REMODELING AFTER CALCAR RECONSTRUCTION WITH METAL WIRE MESH AND IMPACTION BONE GRAFTING: A CASE REPORT." Nagoya University School of Medicine, 2013. http://hdl.handle.net/2237/18479.

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Chay, Siew Han. "Vascular endothelial growth pattern during demineralized bone matrix (intramembranous bone origin) induced osteogenesis." Click to view the E-thesis via HKUTO, 1999. http://sunzi.lib.hku.hk/HKUTO/record/B38628417.

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Cvijic, Gojko 1971. "Comparação clinica e radiografica do carregamento protetico precoce entre implantes com superficies fisica e quimicamente modificadas, inseridos em areas enxertadas em maxila." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289075.

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Orientador: Frederico Andrade e Silva
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-13T01:24:11Z (GMT). No. of bitstreams: 1 Cvijic_Gojko_M.pdf: 808997 bytes, checksum: 9dea6418612a9a36ca0683f628728557 (MD5) Previous issue date: 2009
Resumo: Varias pesquisas tem mostrado que aumento de energia na superfície e a fabricação do implante na ausência de ar, aumenta a hidrofilia da superfície reduzindo o tempo da osseointegração. O objetivo desse estudo foi a avaliar o tempo de vida útil e o Nível de Reabsorção Óssea (NRO) entre os implantes com superfícies química (SLActive) e fisicamente (SLA) tratadas, instalados em maxilas previamente enxertadas com osso autógeno em bloco, e carregados com coroas unitárias parafusadas. Foram utilizados 17 voluntários e 20 implantes (10 com superfície SLA e 10 com superfície SLActive). Dez semanas após a instalação dos implantes no grupo controle (SLA) e 4 semanas no grupo teste (SLActive), foram iniciados os procedimentos para a confecção das próteses parafusadas. Os pilares foram apertados com força de 35Ncm, 12 semanas após a colocação dos implantes com superfície SLA e após 6 semanas com a superfície SLActive. As radiografias periapicais foram tomadas e avaliadas no ato da colocação dos implantes, no dia de aperto do pilar, e, 1 e 3 meses com a coroa definitiva em função. Foi realizada a comparação do NRO entre dois tipos de superfícies. Dois implantes SLActive foram perdidos durante o aperto dos pilares. Os resultados mostraram que NRO ao redor dos implantes com 3 meses em função foi menor no grupo teste quando comparado com grupo controle. Os implantes com superfície SLActive instalados na maxila, na área tratada com enxerto ósseo em bloco, e carregados com coroas unitárias 6 semanas após a instalação, tiveram menor vida útil quando comparados com implantes com superfície SLA.
Abstract: Many researches have shown that higher energy of dental implants and production in chamber without air, enlarge surface hidrofilicity and reduce osseointegration time. The aim of this study was to evaluate the survival rate and the Level of Bone Resorption (LBR) between the implants with chemically and physically treated surfaces, placed in maxillae previously treated with bone block grafts, and loaded with single screwed crowns. Seventeen patients were treated with 20 implants (10 with SLA and 10 with SLActive surface). Ten weeks after implant placement in control group (SLA) and four weeks in test group (SLActive) we began with prosthodontical treatment. The abutments were tightened with 35Ncm, 12 weeks after placement of implants with SLA surface, and after 6 weeks with SLActive surface. Periapical radiographies were made and evaluated after implant placement, after abutment tightening, 1 and 3 months with crown in function. We have done a comparison of LBR between two surfaces. The results have shown that LBR around the implants in function was smaller in the test group comparing to the control group, while implants with SLActive surfaces placed in maxillae, previously treated with bone block graft, and loaded with single screwed crowns 6 weeks after, have smaller survival rate comparing to SLA implants.
Mestrado
Protese Dental
Mestre em Clínica Odontológica

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Day, Adam George Edward. "The optimisation of tissue regeneration for bone grafts." Thesis, Swansea University, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678386.

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Tilley, Simon. "Seeding of Human Bone Marrow Stromal Cells onto Bone Graft Substitutes and Allograft - An Impaction Grafting Model." Thesis, University of Southampton, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494385.

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Tuominen, T. (Tapio). "Native bovine bone morphogenetic protein in the healing of segmental long bone defects." Doctoral thesis, University of Oulu, 2001. http://urn.fi/urn:isbn:9514264789.

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Abstract A new animal model was developed to evaluate the effect of bovine native bone morphogenetic protein (BMP) on the healing of segmental, critical-sized bone defects. Laboratory-bred adult beagle dogs were used in the study. A 2 cm corticoperiosteal defect was created using an oscillating saw in mid-ulna, and the defect was treated with bone grafts and implants fixed by an intramedullary Kirschner wire through predrilled holes in the middle of the implant. Plate and screw fixation was also used in some groups. Coral, hydroxyapatite and demineralized xenograft bone were placed in the defects with or without BMP. Autografts and allografts were used as controls. The BMP was extracted from bovine diaphyseal bone. The follow-up period was 36 weeks. Radiographs were taken at regular intervals during the follow-up period, and bone formation and bone union were evaluated. The radiographs were digitized, and callus was measured and CT scans obtained to define bone density. At the end of the study, the bones were harvested and tested mechanically in a torsion machine until failure. After mechanical testing, the bones were reconstructed and histological sections were made. With autograft and allograft bone grafts, healing was nearly complete. Hydroxyapatite and demineralized xenograft bone did not result in healing of the bone defect, while coral enhanced bone formation, but the healing was not comparable to autografts or allografts. Hydroxyapatite implants did not resorb during the 36 weeks of follow-up to enhance bone healing, and there was a fibrous capsule around the hydroxyapatite implants in histology. Xenograft bone was resorbed, and very little bone formation and extensive fibrosis were seen at the implant site. Coral was resorbed and gradually replaced by new bone, but did not heal the defect completely. With every implant, added BMP had a positive effect on healing as evaluated either radiographically, mechanically or histologically. Coral was the most optimal carrier material for BMP among the materials tested in this study. The animal model seems to be suitable for studying the healing of bone defects, as all the animals were physically active from the first postoperative day and did not seem to have problems with motion during the follow-up period. Intramedullary fixation lacks rotational stability, which may have a negative effect on healing. The bones fixed with a plate and screws showed better scores in radiographs and were mechanically stronger, although the study groups were too small to allow definitive conclusions. As a conclusion, none of the transplants or implants were equally efficient as cortical autograft in healing segmental ulnar defects. BMP did not enhance the poor capacity of hydroxyapatite and xenograft bone to heal the bone defect. According to the present findings, the composite implant consisting of coral and BMP seemed to be the best of the composite implants tested.

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Campbell, David Graham. "Sterilization of HIV infected bone allografts /." Title page, contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phc1869.pdf.

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Porter, Alexandra Elizabeth. "Ultrastructural comparison of hydroxyapatite and silicon-substituted hydroxyapatite for bone grafting applications." Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620067.

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謝秀嫻 and Siew Han Chay. "Vascular endothelial growth pattern during demineralized bone matrix (intramembranous bone origin) induced osteogenesis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B38628417.

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Abbah, Sunny Akogwu. "Towards an injectable bone graft substitute: evaluation of sodium alginate microcapsules for bone tissueengineering." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B39329951.

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周明忠 and Ming-chung Chow. "The healing of endochondral bone grafts in the presence of the demineralized intramembranous bone matrix: :a qualitative andquantitative analysis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B38628429.

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Chow, Ming-chung. "The healing of endochondral bone grafts in the presence of the demineralized intramembranous bone matrix :a qualitative and quantitative analysis." Click to view the E-thesis via HKUTO, 1999. http://sunzi.lib.hku.hk/HKUTO/record/B38628429.

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陸梅 and Mei Lu. "Allogeneic bone grafts mixed with basic fibroblast growth factor: a cellular and molecular study." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B29866340.

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Rewinkel, Scott Everett. "The effects of SiO₂, ZnO, and MgO doping on the mechanical and biological properties of beta-tricalcium phosphate bioceramics for bone tissue engineering, in vitro and in vivo analysis." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Fall2009/s_rewinkel_100909.pdf.

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Thesis (M.S. in mechanical engineering)--Washington State University, December 2009.
Title from PDF title page (viewed on Jan. 22, 2010). "School of Mechanical and Materials Engineering." Includes bibliographical references (p. 123-128).

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Chen, Jinbiao Prince of Wales Clinical School UNSW. "In vitro and in vivo bone formation - assessment and application." Awarded by:University of New South Wales. Prince of Wales Clinical School, 2006. http://handle.unsw.edu.au/1959.4/24922.

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Background: Bone-grafting materials are required in orthopaedic surgery to treat bone defects. Bone formation assessment is required for the development of new strategies and approaches and for quality assurance and quality control of currently available materials. Approaches to the assessment of bone formation are yet to be systematically established, quantified and standardized. Aims: the overall aim of this study was to establish a set of comprehensive quantitative approaches for the assessment of bone formation and to evaluate the role of osteoblastic cells, growth factors, and scaffolds on this process. Materials & methods: both in vitro and in vivo parameters for osteoblast phenotype and bone formation were tested in osteosarcoma cell lines, Saos-2 and U2OS cells, mesenchymal cell line, C2C12 cells, primary adipose derived stromal cells (ADSCs), platelet rich plasma (PRP), and morselized bone grafts. The in vitro parameters used were measurement of alkaline phosphatase (ALP) activity, detection of bone nodules and biomineralization, and quantification of immunocytochemistry and conventional RT-PCR of osteoblast genotyping. In vivo parameters involved ectopic bone formation in nude mice and nude rats and a tibial defect model in nude rats. Histomorphometric and quantitative immunohistochemical analyses were also performed. Results: The in vitro characterization and ectopic bone formation capabiltity of Saos-2 and U2OS cells have been established. Saos-2 cell line, which presents many osteoblast genotype and phenotype, is a stable positive control for both in vitro and in vivo bone formation assessments. The measurement of ALP activity in both solid and liquid phases has been standardized. Both the genotype and phenotype of osteoblast lineage cells has been quantitatively assessed during the capability testing of ADSCs and PRP. Quantitative assessment of new bone formation and related protein markers in vivo has been successfully established through the testing of the biological properties of gamma irradiated morselized bone grafts. Conclusion: A comprehensive knowledge of the assessment of bone regeneration and formation in vitro and in vivo has been integrated and developed through years of study. A whole set of in vitro and in vivo approaches for the assessment of bone formation has been modified and standardized to best suit the different clinical applications. This thesis provides an outline of both in vitro and in vivo bone formation assessment and their clinical applications.

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Kingsmill, Virginia Jane. "Bone structure and turnover in the adult human mandible." Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.480655.

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Grimm, Bernd. "Mechanical properties of morsellised bone graft and synthetic graft extenders for impaction grafting." Thesis, University of Bath, 2003. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760845.

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Bolland, Benjamin J. R. F. "Mechanical and biological augmentation of allograft and synthetic graft in impaction bone grafting." Thesis, University of Southampton, 2008. https://eprints.soton.ac.uk/79021/.

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Aims: This thesis has three main aims: • To investigate the potential role of human bone marrow stromal cells (HBMSC) in Impaction Bone Grafting (IBG). • To investigate the potential role of a synthetic graft, Poly (DL-lactic acid), (PDLLA) as a tissue engineering scaffold and a graft extender in IBG. • To investigate methods to improve graft compaction and reduce fracture risk in IBG. Methods: Part I: The biocompatibility and mechanical properties of HBMSC seeded onto allograft or PDLLA were compared to allograft or PDLLA alone in vitro. Part II: Evidence of biocompatibility, neovascularisation and new bone formation in impacted allograft and PDLLA scaffolds seeded with HBMSC, in vivo was assessed and compared to allograft and PDLLA alone. Part III: The laboratory work was translated into the clinical setting with implantation of impacted allograft seeded with HBMSC for the treatment of bone defects in two case studies. Part IV: The role of vibration in IBG technique to reduce fracture risk and improve graft compaction and prosthetic stability was assessed in an in vitro femoral IBG model. Results: Part I: HBMSC seeded onto morsellised allograft or PDLLA, and cultured under osteogenic conditions in vitro were able to withstand the forces equivalent to a standard femoral impaction and were able to differentiate and proliferate along the osteogenic lineage. The living composite formed provided a biomechanical advantage, with increased interparticulate cohesion and shear strength when compared to allograft alone. Part II: HBMSC seeded onto morsellised allograft or PDLLA, impacted and implanted subcutaneously in nude mice demonstrated cell viability and histological evidence of new bone formation and neovascularisation after 28 days. Part III: In two case studies impacted allograft augmented with marrow-derived autogenous cells was used to treat bone voids in the proximal femur. Both patients made an uncomplicated clinical recovery. Imaging confirmed filling of the defects with very encouraging initial graft incorporation. Histochemical staining of graft samples demonstrated that a live composite graft with osteogenic activity had been introduced into the defects. Alkaline phosphatase and immunohistochemical staining techniques confirmed the bone phenotype of the autotransplanted cells. Part IV: Vibration assisted compaction of morsellised allograft reduced the peak loads and hoop strains transmitted to the femoral cortex during graft compaction, improved graft compaction in the proximal and middle femoral regions, which in turn conferred improved mechanical stability of the prosthesis under cyclical loading, demonstrated by a reduction in stem subsidence. Conclusions: • HBMSC when combined with either allograft or synthetic graft (PDLLA) can survive the forces of a standard IBG and under osteogenic conditions, differentiate and proliferate along the osteogenic lineage. HBMSC and allograft / PDLLA composites confer an additional biomechanical advantage over allograft / PDLLA alone. • Increased new bone formation and neovascularisation has been demonstrated in vivo in allograft and PDLLA / HBMSC composites compared to allograft or PDLLA alone. • Tissue engineering principles combining morsellised allograft and HBMSC composites have been utilised to fill bony voids in two clinical cases, with good clinical outcome. • By reducing peak loads, hoop strains and femoral fracture risk, and improving graft compaction and prosthetic stability the use of vibration and a perforated tamp is a potential new safer more flexible IBG technique. • Utilising tissue engineering techniques and improved graft impaction methods provides avenues to augment the biological and mechanical properties of morsellised allograft, and potentially increase the longevity of revision hip arthroplasty performed using the IBG technique.

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Jayasekera, Tissa R. "Autogenous Secondary Alveolar Bone Grafting In The Treatment Of Cleft Lip And Palate." Thesis, The University of Sydney, 1989. http://hdl.handle.net/2123/4871.

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Salmasi, S. "Development of a hydroxyapatite/POSS-PCU composite film for bone grafting and augmentation." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1563547/.

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The current approach towards treating critical size bone defects, with the aim of repairing or regenerating bone, is the use of bone grafts (autografts or allografts). However, due to various disadvantages associated with the use of autografts and allografts, biomaterials; synthetic ceramic/polymer composites as bone grafts substitutes and guided bone regeneration membranes in particular, have been recognised as effective alternatives to the traditional methods. Polyhedral oligomeric silsesquioxane covalently bonded to poly(carbonate- urea-urethane), (POSS-PCU), a novel co-polymer, has displayed improved physico-chemical and material-cell interaction properties, which have led to variety of investigations on clinical applications of this material such as in synthetic heart valve production, bypass grafts, POSS-PCU coated stents and biomaterial scaffolds. In this thesis, hydroxyapatite incorporated POSS-PCU composite films were developed and examined for the purpose of bone grafting and augmentation. Various concentrations of hydroxyapatite, filler integration and fabrication techniques as well as in vitro models were used to find the most suitable HA/POSS-PCU based composite film that has a closer characteristics to natural bone and enhances bone repair and new bone formation for bone grafting and augmentation applications. It was shown that hydroxyapatite has a concentration-dependent effect on the physico-chemical and material-cell interaction properties of POSS-PCU. In addition, it was shown that hydroxyapatite particles were exposed on the surface of the 50 wt% HA/POSS-PCU composite films and enhanced the bioactivity of these composite films in simulated body fluid. Finally, optimisation of the samples using surface solvent etching and porosity showed that the former increased surface hydrophobicity and reduced mechanical properties of both HA incorporated and HA free POSS-PCU films. Amongst all of the HA/POSS-PCU based composite films investigated here porous 50 wt% HA/POSS-PCU composites showed the most enhanced material-cell interaction properties. In conclusion, HA/POSS-PCU composites have the potential to be further investigated for bone augmentation as guided bone regeneration membranes.

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Conway, Jordan C. "Highly silicated hydroxyapatite : synthesis, characterisation and evaluation." Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=235581.

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Tanaka, Kojiro. "A bioactive and bioresorbable porous cubic composite scaffold loaded with bone marrow aspirate: A potential alternative to autogenous bone grafting." Kyoto University, 2010. http://hdl.handle.net/2433/120597.

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Tayton, Edward R. "Novel approaches towards the successful implementation of tissue engineering strategies in impaction bone grafting." Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/375050/.

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De, Santis Enzo [UNESP]. "Reparação do tecido ósseo peri-implantar após enxerto ósseo autógeno e heterógeno: estudo experimental histológico em cães." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/103317.

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Made available in DSpace on 2014-06-11T19:32:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-09-05Bitstream added on 2014-06-13T21:04:26Z : No. of bitstreams: 1 desantis_e_dr_araca.pdf: 2787266 bytes, checksum: b11c83dbba262a0641d23d2d0ceb74da (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Objetivo: avaliar a regeneração da crista óssea alveolar e o processo de osseointegração de implantes instalados em sítios enxertados com blocos de osso autógeno e osso bovino mineral (DBBM),associado a membrana de colágeno. Material e método: em 6 cães labradores foram extraidos os molares inferiores bilateralmente, nos quais foi removida a tábua óssea vestibular, criando-se um defeito em formato de caixa. Após 3 meses de regeneração, os retalhos foram elevados e posicionado um guia com uma lima endodôntica, com a finalidade de alinhar paralelamente à parede vestibular do defeito. O guia foi removido e, no lado direito inferior (grupo controle), foi obtido um enxerto ósseo do ramo ascendente da mandibula, que foi fixado a parede lateral do defeito por meio de parafusos. No lado esquerdo inferior (grupo teste), foi fixado um bloco de DBBM no defeito mandibular. Em ambos os lados, os blocos enxertados foram protegidos por uma membrana de colágeno reabsorvível. Em seguida os retalhos foram suturados. Após elevação do retalho, utilizou-se o guia para instalação de um implante de cada lado da mandíbula, entre o enxerto e o osso remanescente. Após 3 meses, os animais foram eutanasiados para obtenção das peças a serem processadas laboratorialmente para análise histológica. Resultados: Todos os implantes apresentaram-se clinicamente estáveis. A espessura da crista alveolar no grupo teste foi de 5.4, 9.4 e 9.3 mm, antes, imediatamente após a enxertia, e no momento da instalação dos implantes respectivamente. No grupo controle (enxerto ósseo autógeno), a espessura da crista alveolar foi de 5.2, 9.0 mm antes e imediatamente após o procedimento de enxertia (reconstrução). Após 3 meses...
Aim: - to evaluate the healing of the alveolar bony crest and the integration of implants installed in augmented sites with autologous bone or DBBM blocks, concomitantly with a collagen membrane. Material & methods: Mandibular molars were extracted bilaterally in 6 Labrador dogs, the buccal bony wall was removed and a box-shaped defect was created. After 3 months, flaps were elevated and a device was applied to a stent and used for the placement of an endodontic file that was lined up parallel to the buccal wall of the defect. The stent was removed and, in the right mandibular side, a bony graft was harvested from the ascending ramus and secured to the lateral wall of the defect by means of screws. In the left mandibular side, a DBBM block was fixed to the defect. A resorbable membrane was applied both sides. The flaps were sutured. After three months, one bone graft was exposed, and the dog was excluded from further analysis. After flap elevation, the stent and the device were used as guide to install one implant in each mandibular side, between the graft and the parent bone. After 3 months, biopsies were harvested and ground sections prepared for histological evaluation. Results: All implants were clinically stable. The width of the alveolar crest at the test sites was 5.4mm before, 9.4mm immediately after grafting, and 9.3mm at implant installation. At the control sites (autologous bone graft), the width of the alveolar crest was 5.2mm before and 9.0mm immediately after the grafting procedure. After 3 months of healing, the width was 8.7mm. One autologous bone block graft was lost before implant installation. All implants installed were available for histological evaluation (n=5). The autologous bone... (Complete abstract click electronic access below)

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Tong, Chi-kit Antonio, and 唐志傑. "Meniscectomy and autogenous graft reconstruction of the rhesus monkey temporomandibular joint articular disc." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B29821691.

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Tong, Chi-kit Antonio. "Meniscectomy and autogenous graft reconstruction of the rhesus monkey temporomandibular joint articular disc /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20377897.

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Dunlop, D. G. "Mechanical and biological aspects of impaction bone grafting in revision hip surgery and the use of a new synthetic bone graft." Thesis, University of Edinburgh, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.649798.

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This thesis examines, in three phases, the biological and mechanical properties of impacted morcellised bone graft and the use of synthetic additives. Phase I. The mechanical strengths of different mixtures of bone graft were found to follow sound Engineering principles. The distribution of particle sizes from different bone mills determines the mechanical strength of graft from that mill. Theoretical increases in strength by improving particle size distribution were confirmed by mechanical tests Washing the graft or the addition of synthetic additives (Controlled Release Glass - Corglaes^(r) (Giltech Ltd. Ayr, Scotland) & Tricalcium Phosphate/Hydroxyapatite - TCP/HA (Stryker Howmedica Osteonics, Berkshire, England)) also improved strength. Phase II. An in-vivo ovine defect model allowed biological assessment of impacted pellets, made of mixtures found in Phase I to be mechanically strong. Bone densitometry and histological analysis were used. Phase III. An ideal mixture of bone graft and an additive was compared with allograft bone alone, in an ovine femoral revision hip replacement model. The subsistence over time and 3D micromotions under load of the implant were similar between the two groups. Histological analysis showed increased biological activity around the proximal femur in contrast to the relative isolation of the distal graft. These experiments highlight potential mechanisms with which to improve impacted bone graft strength and support further analysis of Corglaes^(r) and TCP/HA as bulking agents and/or bone graft enhancers.

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Dissertations / Theses on the topic 'Bone-grafting'

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