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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.
41

Avaliação do enxerto ósseo autógeno e estudo da osseointegração de implantes nos períodos de incorporação e maturação óssea em áreas submetidas a cirurgia de enxerto ósseo em elevação de seio maxilar

Nunes, Luiz Marcelo Amaral Galvão 06 September 2016 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-01-06T14:00:14Z No. of bitstreams: 1 luizmarceloamaralgalvaonunes.pdf: 1165890 bytes, checksum: 617cb8b85316ada8b08107c635bf0730 (MD5) / Approved for entry into archive by Diamantino Mayra (mayra.diamantino@ufjf.edu.br) on 2017-01-31T11:27:08Z (GMT) No. of bitstreams: 1 luizmarceloamaralgalvaonunes.pdf: 1165890 bytes, checksum: 617cb8b85316ada8b08107c635bf0730 (MD5) / Made available in DSpace on 2017-01-31T11:27:08Z (GMT). No. of bitstreams: 1 luizmarceloamaralgalvaonunes.pdf: 1165890 bytes, checksum: 617cb8b85316ada8b08107c635bf0730 (MD5) Previous issue date: 2016-09-06 / A Implantodontia, afim de, proporcionar melhores resultados estéticos e funcionais, tem apresentado inúmeras inovações e tecnologias visando alcançar estes objetivos associado a redução do tempo de tratamento. Contudo pacientes que apresentam a necessidade de cirurgias de reconstruções associadas a enxertos ósseos visando à instalação adequada destes implantes permanecem como desafios. Deste modo, o presente trabalho analisou o enxerto ósseo autógeno em dois diferentes períodos e avaliou os implantes instalados nestes períodos analisados, a pesquisa foi subdividida e descrita nos Capítulos à seguir. CAPITULO I: Análise histológica das características existentes no processo de incorporação e maturação óssea em áreas submetidas à cirurgia de enxerto ósseo em elevação de seio maxilar. Observou-se nos dois períodos analisados, correspondentes do processo de reparo ósseo, que foram semelhantes em ambos períodos. Deste modo, pode-se concluir que o enxerto ósseo autógeno apresenta características semelhantes na fase de incorporação (2 meses) e maturação (6 meses) o que possibilita a manipulação deste tecido na fase mais inicial sem o seu comprometimento. CAPITULO II: O propósito deste capítulo foi avaliar a osseointegração em dois períodos diferentes sendo, incorporação (2 meses) e maturação (6 meses) óssea em áreas submetidas a cirurgia de enxerto ósseo em elevação de seio maxilar e a estabilidade da prótese instalada. Observou-se nos dois períodos analisados, a incorporação óssea (2 meses) e maturação óssea (6 meses), que embora divergentes nas etapas de reparo ósseo, apresentaram resultados semelhantes para a osseointegração e estabilidade da prótese. Deste modo, pode-se concluir que a inserção de implantes osseointegráveis nestas regiões em menor período de reparo, ou seja, na fase de incorporação óssea (2 meses) não compromete a osseointegração nem tão pouco a estabilidade da prótese a longo prazo. A redução do tempo de tratamento de pacientes submetidos a cirurgias de reconstruções com enxerto ósseo em elevação de seio maxilar é possível realizando a instalação dos implantes no período de incorporação óssea. / The implantology in order to provide better aesthetic and functional results, presented numerous innovations and technologies to achieve these goals associated with reduced treatment time. However patients who have the need for reconstructive surgery associated with bone grafts seeking the proper installation of these implants remain as challenges. Thus, this work presents two studies described in the following chapters. Article I: Histological analysis of existing resources in the process of development and maturation in areas prone to bone graft surgery in sinus floor elevation. It was observed in both periods analyzed, bone repair, which were similar in both the periods. Thus, it can be concluded that autogenous grafts has similar characteristics in the incorporation phase (2 months) and mature (6 months), allowing the tissue manipulation in the initial stage without their involvement. Article II: The objective of this chapter was to evaluate the osseointegration in two different periods being, incorporation (2 months) and maturity (6 months) bone in areas subjected to bone graft surgery in sinus floor elevation and stability of the installed prosthesis. It was observed in both study periods, the bone ingrowth (2 months) and maturation (6 months), although at different stages of bone healing that showed similar results for bone integration and stability of the prosthesis. Thus, it can be concluded that the insertion of dental implants in these regions in the shortest repair, namely on bone growth phase (2 months) does not jeopardize the osseointegration or long-term stability of the prosthesis. The reduction in the treatment of patients undergoing reconstructive surgery with bone grafting time in sinus floor elevation is possible to perform the installation of implants in bone growth period.
42

3D-volldigitalisierte Behandlungsplanung bei Lippen-Kiefer-Gaumenspalten (LKGS-3D)

Keil, Christiane, Haim, Dominik, Zeidler-Rentzsch, Ines, Tritschel, Franz, Weiland, Bernhard, Müller, Olaf, Treichel, Thomas, Lauer, Günter 06 September 2021 (has links)
Die Idealvorstellung eines vollständig digitalisierten Behandlungsalltags rückt mit fortschreitender technologischer und informationeller Entwicklung stetig näher an die Realität. Zu Beginn bestand lediglich die Möglichkeit einer elektronischen Patientenakte, hinzu kamen vielfältige Möglichkeiten der digitalen Bildgebung und wurden schließlich um das Ziel eines vollständigen digitalen Workflows ergänzt. Die Planung der interdisziplinären kieferorthopädischen / kieferchirurgischen Versorgung von Patienten mit Lippen-Kiefer-Gaumen-Spalten (LKGS) wurde bis vor kurzem am Universitätsklinikum Dresden noch hauptsächlich analog durchgeführt. Eine volldigitalisierte Behandlungsplanung unter Einbeziehung aller beteiligten Behandler fand nicht statt. Ziel des Projektes war es deshalb, eine digitale Plattform zur interdisziplinären zahnmedizinischen Versorgung von LKGS-Patienten zu schaffen. Dazu wurde zuerst die bisher erforderliche Abdrucknahme mittels Alginat und die anschließende Herstellung eines Gipsmodells durch einen intraoralen 3D-Scan der Zahnbögen des Patienten abgelöst. Anhand des intraoralen 3D-Scans können nun die erforderlichen Trinkplatten mittels 3D-Druck erstellt werden. Zweiter Schritt war die Anfertigung von 3D-Aufnahmen der Weichteile des Gesichtes mittels eines extraoralen 3D-Scanners. Als dritter Schritt erfolgte die Anfertigung von Digitalen Volumentomografie (DVT)-Aufnahmen zur 3D-Darstellung des Schädelknochens und Kieferskeletts. Nach der Anfertigung wurden diese bildbasierten Datensätze zu einem „digitalen Zwilling“ (virtuelles 3D-Modell aus DVT, intra- und extraoralen 3D-Scan) zusammengefasst, wodurch erstmalig ein umfassendes 3D-Modell des Mund-Kiefer-Raumes einschließlich wichtiger Informationen zum Kiefergelenk und der anliegenden Weichteile entstand. Dieses virtuelle Modell bildet jetzt die Grundlage für die Behandlungsplanung und die Planung der weiteren zahnmedizinischen und medizinischen Versorgung. Es konnte also im Projekt die komplette Digitalisierung der Diagnostik, die Etablierung einer Fusionsplattform und der Datenaustausch zwischen Uniklinik und privater Praxis umgesetzt werden.
43

Preklinické využití a kritické zhodnocení mikro-CT z pohledu orální a maxilofaciální chirurgie. / Preclinical use and critical evaluation of micro-CT from the perspective of oral and maxillofacial surgery.

Bartoš, Martin January 2020 (has links)
The preclinical imaging method micro-CT (microtomography) allows the visualization and quantification of the structure of samples at a resolution of micrometers. Its' importance is increasing globally. In addition to several advantages (non-destructive, the possibility of direct 3D analysis, time efficiency, etc.), micro-CT also has some significant limitations (problematic validation of results, image artifacts, significant influence of image modifications, etc.). This thesis focuses on the application of micro-CT in the field of research and development of metallic and non-metallic materials promoting bone healing with their possible clinical applications. The first part addresses the limitations of micro-CT through several studies. A comparison of pore sizes in biomaterials utilizing scanning electron microscopy (SEM) and micro-CT was performed, and the complications of pore size evaluation were presented. SEM image analysis leads to significantly higher values than micro-CT (approximately three times), which allows for comparison of the studies using only one of these methods. Validation of micro-CT 3D analysis results based on calibration phantoms with complex structure, to date, is not possible. We therefore developed software generating phantom datasets of 3D objects with well-defined...
44

Cost minimization analysis of indication-specific osteosynthesis material in oral and maxillofacial surgery

Franke, Adrian, Weiland, Bernhard, Bučkova, Michaela, Bräuer, Christian, Lauer, Günter, Leonhardt, Henry 22 February 2024 (has links)
Purpose Following the introduction of the Regulation (EU) 2017/745 by the European Parliament, any bioactive substance or surgical implant introduced into the human body must be documented. The regulation requires any implant to be traced back to the manufacturer. Lot numbers need to be available for every single medical implant. Also, the manufacturer is required by law to provide implants individually packaged and sterilized. Previously, model tray systems (MOS tray) were used for osteosynthesis in oral and maxillofacial surgery, in which the individual implants could not be registered separately. The new regulation made it impossible to use such processes during surgery anymore and a need for a change in the medical practice surged. We examined a possible solution for the new legislation. The aim of this prospective cohort study is to analyze the MOS tray systems to osteosynthesis materials prepackaged in sets. We record and evaluate parameters such as surgical time and documentation time. We perform a short cost analysis of our clinic. The primary aim is to determine how much time is gained or lost by the mandatory increased patient safety. The secondary aim is to describe change in costs. Methods Patients that underwent standard surgical procedures in the clinic of oral and maxillofacial surgery of the faculty hospital Carl Gustav Carus in Dresden were included. We chose open reduction and internal fixation (ORIF) of anterior mandibular corpus fractures as well as mandibular advancement by means of bilateral sagittal split osteotomies (BSSO) as standardized procedures. Both of these procedures require two osteosynthesis plates and at least four screws for each plate. MOS trays were compared to prepackaged sterilized sets. The sets include a drill bit, two plates, and eight 5-mm screws. A total number of 40 patients were examined. We allocated 20 patients to the ORIF group and the other 20 patients to the BSSO group. Each group was evenly subdivided into a MOS tray group and a prepackaged group. Parameters such as the incision-suture time (IST) as well as the documentation time (DT) by the operating room (OR) staff to complete documentation for the implants are the main focus of investigation. Results For open reduction, the incision-suture time was significantly different in favor of the MOS tray (p < 0.05). There was no difference in the BSSO groups. However, we observed a significantly different (p < 0.01) documentation time advantage for the prepackaged sets in both the ORIF and BSSO groups. On top of that, we find that by using the prepackaged kits, we are able to reduce sterilization costs by €11.53 per size-reduced container. Also, there is also a total cut of costs of €38.90 and €43.70, respectively, per standardized procedure for implant material. Conclusions By law, a change in the method of approaching surgery is necessary. For standardized procedures, the right choice of implants can lead to a reduction of documentation time and costs for implant material, sterilization, as well as utilizing less instruments. This in turn leads to lower costs for perioperative processing as well as provision of state-of-the-art implant quality implementing higher patient security.
45

BIOERODIBLE CALCIUM SULFATE BONE GRAFTING SUBSTITUTES WITH TAILORED DRUG DELIVERY CAPABILITIES

Orellana, Bryan R 01 January 2014 (has links)
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.
46

3D-volldigitalisierte Behandlungsplanung bei Lippen-Kiefer-Gaumenspalten

Kunert-Keil, Christiane, Haim, Dominik, Kozak, Karol, Zeidler-Rentzsch, Ines, Weiland, Bernhard, Müller, Olaf, Treichel, Thomas, Lauer, Günter 03 January 2020 (has links)
Die Idealvorstellung eines vollständig digitalisierten Behandlungsalltags rückt mit fortschreitender technologischer und informationeller Entwicklung stetig näher an die Realität. Zu Beginn bestand lediglich die Möglichkeit einer elektronischen Patientenakte, hinzu kamen vielfältige Möglichkeiten der digitalen Bildgebung und wurden schließlich um das Ziel eines vollständigen digitalen Workflows ergänzt. Die Planung der interdisziplinären kieferorthopädischen / kieferchirurgischen Versorgung von Patienten mit Lippen-Kiefer-Gaumen-Spalten (LKGS) wird momentan noch hauptsächlich analog durchgeführt. Eine volldigitalisierte Behandlungsplanung und –freigabe unter intersektoraler Einbeziehung aller beteiligten Behandler findet nicht statt. Neu entwickelte, digitale kieferorthopädische und –chirurgische Produkte, welche bis vor ein paar Jahren noch nicht denkbar waren, unterstützen den digitalen Workflow maßgeblich. 3D-Scanner und 3D-Fotoaufnahmen erstellen digitale Modelle, deren Daten zur Integration in den digitalen Workflow durch Softwareprozesse verarbeitet werden müssen. Um einen einfachen und strukturierten Zugriff auf die gesamten 3D Daten zu gewährleisten, ist die Idee entstanden, die anfallenden Daten und Unterlagen zu digitalisieren und in einer für diesen Zweck entwickelten Datenbank zu speichern und zu bearbeiten. Die konsequente Verwendung von digitalen 3D-Analysen und der Verzicht auf die aufwändige Erstellung der Diagnostik- und Therapieplanung aus einer Kombination von Gipsmodellen und 2D-Daten (z.B. Röntgenbilder) führen zu einer fundamentalen und richtungsweisenden Veränderung des Behandlungsplanungsprozesses. Räumlich und monetär aufwendige Bearbeitungsprozesse werden eingespart und Behandlungspläne können rascher erstellt werden, da sich alle notwendigen Unterlagen gebündelt in einem System wiederfinden. Weiterhin wird die Strahlenbelastung der Patienten wesentlich verringert, da eine Doppeldiagnostik durch mehrmaliges Anfertigen von Röntgenaufnahmen, DVTs und CTs in verschiedenen Abteilungen vermieden wird. Die Kommunikation, der Austausch und die konsiliarische Zusammenarbeit zwischen den Behandlern erfolgt unter Verwendung der europaweit ersten offenen, überregionalen telemedizinischen Plattform zur Verbesserung der medizinischen Versorgung – CCS TELEHEALTH OSTSACHSEN (THOS). [... aus der Einleitung]
47

Enhancing Anticoagulation Monitoring and Therapy in Patients Undergoing Microvascular Reconstruction in Maxillofacial Surgery: A Prospective Observational Trial

Schröder, Tom A., Leonhardt, Henry, Haim, Dominik, Bräuer, Christian, Papadopoulos, Kiriaki K., Vicent, Oliver, Güldner, Andreas, Mirus, Martin, Schmidt, Jürgen, Held, Hanns C., Birkner, Thomas, Beyer-Westendorf, Jan, Lauer, Günter, Spieth, Peter M., Koch, Thea, Heubner, Lars 04 June 2024 (has links)
Background: In reconstructive surgery, loss of a microvascular free flap due to perfusion disorders, especially thrombosis, is a serious complication. In recent years, viscoelastic testing (VET) has become increasingly important in point-of-care (POC) anticoagulation monitoring. This paper describes a protocol for enhanced anticoagulation monitoring during maxillofacial flap surgery. Objective: The aim of the study will be to evaluate, in a controlled setting, the predictive value of POC devices for the type of flap perfusion disorders due to thrombosis or bleeding. VET, Platelet monitoring (PM) and standard laboratory tests (SLT) are comparatively examined. Methods/Design: This study is an investigator-initiated prospective trial in 100 patients undergoing maxillofacial surgery. Patients who undergo reconstructive surgery using microvascular-free flaps will be consecutively enrolled in the study. All patients provide blood samples for VET, PM and SLT at defined time points. The primary outcome is defined as free flap loss during the hospital stay. Statistical analyses will be performed using t-tests, including the Bonferroni adjustment for multiple comparisons. Discussion: This study will help clarify whether VET can improve individualized patient care in reconstruction surgery. A better understanding of coagulation in relation to flap perfusion disorders may allow real-time adaption of antithrombotic strategies and potentially prevent flap complications.
48

Avanço Maxilomandibular e Glossectomia da Linha Média no Tratamento da Síndrome da Apnéia Hipopnéia Obstrutiva do Sono Moderada e Severa.

Colombini, Nelson Eduardo Paris 22 March 2010 (has links)
Made available in DSpace on 2016-01-26T12:51:37Z (GMT). No. of bitstreams: 1 nelsoncolombini_tese.pdf: 1052278 bytes, checksum: 65caf5c2304f80f9167fa51d736325f5 (MD5) Previous issue date: 2010-03-22 / To describe the results obtained by the Maxillo Mandibular Advancement (MMA), associated to a glossectomy of Medium Line (GML) to CO2 Laser in the surgical treatment of Obstructive Sleep Apnea-Hypoapnea Syndrome (ASOSH), from moderate to severe, with adequate analysis of macroscstruture e microstructure of the sleep. Casuistics and Method: In the period from February 2005 to December 2008, 22 sequencial patients with ASOSH, from moderate to severe, with or without maxillary mandibular bone alterations, were selected. These patients were submitted to MMP plus GML using a CO2 laser. All patients underwent clinical, polissonographic and cephalometric evaluations. The polissonographic parameters used were: IAH, MD, Minimum SAT O2% < measured in minutes, sleep stages N1, N2, N3 and REM, preoperative and postoperative. The cephalometric parameters used were: SNA, SNB, PAS, PP2 PP2, preoperative and postoperative. Results: Evaluation of eventual differences in the preoperative and postoperative moments were investigated with the appropriate statistical tools. The surgical treatment proved to be effective in 8, out of 22 of the cases (36.36%), according to international criteria of normality. On the other hand, in these patients the IAH was not the best parameter to evaluate the therapeutic success. The MD (68.18% of improvement), stage N3 (59.09% of improvement) and Minimum SAT O2% < 90 measured in minutes (81.81% of improvement) demonstrated that they were the best instruments for characterizing the laboratorial control of the disease. Discussion: The MMA has expanded the dimensions of the pharynx and the hypopharynx. The GLM was associated in order to maximize the VAS, improve the stability of the dental occlusion, as well as the function of the temporomandibular joint, reducing the morbidity of the procedure. A postoperative evaluation with polysomnography showed improvements of the parameters in both macro and microarchitecture of the sleep (in relation to preoperative findings), besides proving that the IAH is not the best parameter for a postoperative evaluation (this applies to the patients of this series). Conclusions: The surgical treatment performed with MMA, associated to the GLM with CO2 laser was effective to treat patients with from ASOSH : - The improvement using the most accepted parameter by the international community (IAH < 5/ hour) was 8 out of the 22 (36.36%); - The IAH was not the best instrument to evaluate the control of the disease; - Were MD, stage N3 and Minimum SAT O2% < 90 measured in minutes showed that they are good indicators of the control of the disease (postoperative moment); - The Minimum SAT O2% < 90 measured in minutes was the best parameter in the evaluation of the surgical treatment (18/22 or 81.81%). / Descrever os resultados obtidos pelo Avanço Maxilo- Mandibular (AMM) associados à Glossectomia de Linha Média (GLM) a Laser CO2 no tratamento cirúrgico da Síndrome da Apnéia/Hipopnéia Obstrutiva do Sono (SAHOS) moderada e severa, usando instrumentos estatísticos que avaliem a arquiquetura do sono quanto à macro e micro estrutura para adequada e real avaliação dos resultados obtidos pelo tratamento proposto. Casuística e Método: No período de fevereiro de 2005 a dezembro de 2008 foram selecionados 22 pacientes seqüenciais portadores de SAHOS moderada e severa, com ou sem alterações esqueléticas maxilo-mandibulares. Estes pacientes foram submetidos à AMM, mais GLM com laser de CO2. Todos pacientes tiveram avaliação clínica, polissonográfica e cefalométrica. Os parâmetros polissonográficos utilizados foram: IAH, MD, SAT O2 % Mínima < 90 medida em minutos, estágios do sono N1, N2, N3 e REM, pré e pósoperatório. Os parâmetros cefalométricos utilizados foram: SNA, SNB, PAS, PP2 PP2 pré e pós-operatório. Resultados: Avaliação de eventuais diferenças nos momentos pré e pós-operatório foram investigadas com ferramenta estatística apropriada. O tratamento cirúrgico mostrou-se eficaz em 8/22 (36,36%) dos casos, segundo critérios internacionais de normalidade. Por outro lado nestes pacientes o IAH não foi o melhor parâmetro para avaliar sucesso terapêutico. MD (68,18% melhora), estágio N3 (59,09% de melhora) e SAT O2% Mínima < 90 medida em minutos (81,81% de melhora) mostraram-se melhores instrumentos para caracterizar controle laboratorial da enfermidade.Discussão: O AMM ampliou as dimensões da faringe e hipofaringe. A GLM foi associada para maximizar a VAS, aumentar a estabilidade da oclusão dentária e função da articulação têmporo-mandibular, reduzindo a morbidade do procedimento. Avaliação pós-operatória com polissonografia demonstrou melhora de parâmetros de macro e micro-arquitetura do sono (em relação aos achados pré-operatórios), além de comprovar não ser o IAH o melhor parâmetro para avaliação pós-operatória (isto para os pacientes desta série). Conclusões: O tratamento cirúrgico com AMM associado à GLM com laser de CO2 foi eficaz para tratar pacientes com SAHOS: A melhora utilizando o parâmetro mais aceito pela comunidade internacional (IAH < 5/hora) foi de 8/22 (36,36%); IAH não foi o melhor instrumento para avaliação do controle da enfermidade; MD, estágio N3 e SAT O2% Mínima < 90 medida em minutos mostraram-se bons indicadores de controle da enfermidade (momento pósoperatório); SAT O2% Mínima < 90 medida em minutos foi o melhor parâmetro na avaliação do tratamento cirúrgico (18/22 ou 81,81%).

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