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The role of imaging techniques in creation of computational models in biomechanics.
Prášilová, Eva ; Valášek, Jiří (referee) ; Marcián, Petr (advisor)
The first part of the bachelor´s thesis is dealt with the processing history of imaging techniques and their indications in a clinical practice. From point of view of the computer modeling, the computer tomography plays an important role in biomechanics. The second part of this treatment describes the scan processing of sections of two human mandible obtained from computer CT and micro-CT tomography. As a non-invasive way procedure can be characterized the image processing techniques, which analyze a bone density and BVF. The manual segmentation was applied in this analysis provided in ROI analysis software. There are shown the graphs of the bone densities of segments of two human mandibles depending on the specimen length and also there are compared the results of the measurements received from the CT and micro-CT tomography. Then follow the results illustrating the correlation of the relations and recalculations, which can be used as the determination tool of the mechanical properties of bone tissue. Finally there are described the computer models created in ANSYS focused on the different bone density analysis and stress strain analysis.
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Biomechanical Study of Tooth Implants for Low Density Bone
Marcián, Petr ; Janíček, Přemysl (referee) ; Horyl, Petr (referee) ; Florian, Zdeněk (advisor)
This work deals with problem of dental implant area, where there are many problems at the dental implants application. The essential issue is the bone tissue quality at implant application, which sig-nificantly influences its deformation, tension and the possibility of subsequent implant failure. The knowledge of bone tissue mechanical properties of mandible and mandible with applied implant can significantly affect prediction of dental implant failure. The mechanical interaction can be described by variable determining deformation and tension of solved system. For this reason the computational modeling by using Finite Element Method was used for solving given problem. The computational model creation of solved system on the high resolution level is necessary for biomechanical assessment of implant failure, including bone tissue quality. For this purpose the biomechanical study was performed, which significantly spreads range of solved problem in this work afterwards. In this work the methodology, which describes assessment of bone tissue quality where the implant should be applied as well as mutual interaction, is presented. The results confirm necessity of bone tissue computational models creation on high resolution level including complex trabecular architecture. In this work the creation of trabecular structure computational model from data gained on micro-CT device is described. Further, the trabecular structure computational model was created on the 3D level with dental implant and the stress strain analysis was performed consequently. The last part of this work deals with introductory study of bone tissue modeling and remodeling.
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Nutrition and Bone Density of Patients of Osteocentre, 3rd Medical Department, General Faculty Hospital in Prague.
Staroveská, Natálie ; Raška, Ivan (advisor) ; Michalská, Dana (referee)
This thesis deals with the relationship between bone quality and lifestyle factors with a focus on nutrition, tobacco use, alcohol consumption and physical activity. The theoretical part of the thesis presents general knowledge about bones, their composition, structure, bone division, growth and development of bones. The next two chapters describe the process of bone remodeling and calcium- phosphate metabolism. The work describes in detail the factors influencing the quality of bone mass, especially those that can be affected, such as the use of tobacco products, alcohol, some drugs and sufficient physical activity. A separate chapter is devoted to the influence of diet on the quality of bone mass. The most common disorders of calcium-phosphate metabolism and their treatment are described as well. The last chapter of the practical part is devoted to the examination of bone metabolism. The aim of the practical part of the diploma thesis was to examine the eating habits and other components of the lifestyle (smoking, physical activity, etc.) of patients of Osteocentre, 3rd Medical Department, General Faculty Hospital in Prague and to find out how these components correlate with the results of densitometric examination of the patients. Data collection was ensured by means of a questionnaire survey,...
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The effect of serum 25-hydroxycholekalciferol levels on musculoskeletal system in children with inflammatory bowel disease
Maratová, Klára ; Šumník, Zdeněk (advisor) ; Zapletalová, Jiřina (referee) ; Kutílek, Štěpán (referee)
The effect of serum 25-hydroxycholekalciferol levels on musculoskeletal system in children with inflammatory bowel disease Background: Low bone mineral density and osteoporosis represent severe secondary complications that can be a result of childhood chronic disease. According to Frost's mechanostat theory impaired muscle functions may contribute to the changes observed on the skeleton. Aims: The aim of this study was to: 1) evaluate parameters of bone mineral density, bone geometry and dynamic muscle functions in children and adolescent with chronic disease - inflammatory bowel disease (IBD) and type 1 diabetes (T1D); 2) evaluate a possible effect of vitamin D deficiency and vitamin D supplementation or duration of the disease on the musculoskeletal unit; 3) determine clinical or laboratory predictors of muscle and bone parameters. Methods: The study was divided into two substudies according to the diagnosis. Seventy patients with IBD (median age 13.8 years) were included in one study, fifty-five of which completed all of the planned procedures. During the study, IBD patients were supplemented with 2000 IU/d of vitamin D. In the second study 95 patients with T1D were included (median age 16.4 years). BMD and bone geometry of non-dominant tibia was evaluated using peripheral quantitative computed...
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The role of peripheral quantitative CT in early diagnostics of osteoporosis in chronically ill children
Souček, Ondřej ; Šumník, Zdeněk (advisor) ; Hoza, Jozef (referee) ; Zapletalová, Jiřina (referee)
Patients with Turner syndrome (TS) have increased fracture risk and decreased bone density, patients with severe hemophilia have low bone density. The etiology of these changes hasn't been completely elucidated in any of the two diseases. Our aimes were to assess bone density and geometry at the radius using a new method peripheral quantitative CT densitometry (pQCT) and to describe associations between densitometry parameters and estrogen treatment in TS and laboratory as well as clinical markers of disease severity in haemophilia. Sixty-seven girls with TS (median age 14.3 years, range 6.0-19.4) and 42 boys with haemophilia (median age 12.7 years, range 6.6-19.2) have been measured using peripheral quantitative CT at the radius. The results have been compared to published reference data. Girls with TS had decreased cortical bone density and thinner cortex. These parameters were positively correlated to the length of estrogen treatment. Trabecular bone density was normal in prepubertal girls but it was decreased after puberty. There was no association between trabecular bone density and the estrogen treatment. Boys with haemophilia had decreased trabecular density and low muscle area at the forearm. Densitometry parameters were influenced neither by the clotting factor VIII/IX level nor by the frequency of...
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Biomechanical Study of Tooth Implants for Low Density Bone
Marcián, Petr ; Janíček, Přemysl (referee) ; Horyl, Petr (referee) ; Florian, Zdeněk (advisor)
This work deals with problem of dental implant area, where there are many problems at the dental implants application. The essential issue is the bone tissue quality at implant application, which sig-nificantly influences its deformation, tension and the possibility of subsequent implant failure. The knowledge of bone tissue mechanical properties of mandible and mandible with applied implant can significantly affect prediction of dental implant failure. The mechanical interaction can be described by variable determining deformation and tension of solved system. For this reason the computational modeling by using Finite Element Method was used for solving given problem. The computational model creation of solved system on the high resolution level is necessary for biomechanical assessment of implant failure, including bone tissue quality. For this purpose the biomechanical study was performed, which significantly spreads range of solved problem in this work afterwards. In this work the methodology, which describes assessment of bone tissue quality where the implant should be applied as well as mutual interaction, is presented. The results confirm necessity of bone tissue computational models creation on high resolution level including complex trabecular architecture. In this work the creation of trabecular structure computational model from data gained on micro-CT device is described. Further, the trabecular structure computational model was created on the 3D level with dental implant and the stress strain analysis was performed consequently. The last part of this work deals with introductory study of bone tissue modeling and remodeling.
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The role of imaging techniques in creation of computational models in biomechanics.
Prášilová, Eva ; Valášek, Jiří (referee) ; Marcián, Petr (advisor)
The first part of the bachelor´s thesis is dealt with the processing history of imaging techniques and their indications in a clinical practice. From point of view of the computer modeling, the computer tomography plays an important role in biomechanics. The second part of this treatment describes the scan processing of sections of two human mandible obtained from computer CT and micro-CT tomography. As a non-invasive way procedure can be characterized the image processing techniques, which analyze a bone density and BVF. The manual segmentation was applied in this analysis provided in ROI analysis software. There are shown the graphs of the bone densities of segments of two human mandibles depending on the specimen length and also there are compared the results of the measurements received from the CT and micro-CT tomography. Then follow the results illustrating the correlation of the relations and recalculations, which can be used as the determination tool of the mechanical properties of bone tissue. Finally there are described the computer models created in ANSYS focused on the different bone density analysis and stress strain analysis.
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Modification of dietary habits and physical activity and its effect on the density of bone tissue of a middle-aged female
JAROŠOVÁ, Veronika
The aim of this thesis is to find out about the effect which have modification of dietary habits and physical activity on the density of bone tissue of a middle-aged female. Intervention programme was prepared for middle-aged female in the length od six months. Intervention programme included modification of dietary habits which meant that the amount of calcium was increased. Programme also included modification of physical aktivity. Training programme was dividend into two parts. There were aerobic physical activities and special work out. Study started in August 2011 and it was finished in February 2012. DXA examination was done to detect bone density. There were two areas to examine - L1-L4 and proximal femur (Neck, Troch, Inter, Ward´s). Apart from bone density, there was also body composition examination. Fat mass, lean mass and total body fat were detected. DXA results from medical examinations for the areas are evaluated in the practical part.
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