Medicine and Health Sciences Commons^™

Disinfection Of Dentin By Intracanal Laser Irradiation: An In Vitro Model, Silvia Cristina Mafra Cecchini

Loma Linda University Electronic Theses, Dissertations & Projects

A possible cause for root canal failure is the persistence of bacteria that have colonized dentinal tubules. To reduce this risk and, if possible, to also shorten the time consuming endodontic therapy, new equipment and materials are constantly being introduced. The aim of the present investigation was to study the effect of disinfection of dentinal tubules by intracanal laser irradiation using an in vitro model. The groups irradiated by various lasers were compared with calcium hydroxide, a material frequently used as intracanal medication between appointments. Freshly extracted, intact bovine incisors were used. The root cementum was removed and the teeth …

Functional Significance Of The Upregulation Of Adhesion Molecules On Irradiated Endothelial Cells, Balabhaskar Prabhakarpandian

Theses and Dissertations (ETD)

Ionizing radiation is a major therapy for cancer. Damage to the endothelium and upregulation of inflammatory responses are major side effects of radiotherapy, but the mechanisms behind these processes are not clear. A key component of the inflammatory response is leukocytes adhesion to the endothelium in a multi-step process involving leukocyte tethering to the endothelium, followed by rolling, firm adhesion/spreading and extravasation. Adhesion molecules mediate this process, particularly, E-selectin and ICAM-1, which are inducible adhesion molecules. E-selectin is involved in the initial tethering and rolling steps of the adhesion cascade while ICAM-1 appears to be involved in the latter steps. …

Qualitative Evaluation Of Data Compression In Real-Time Ultrasound Imaging, Bijoy J. Sundersingh

Theses and Dissertations (ETD)

The purpose of this project was to evaluate qualitatively real-time ultrasound imaging using objective and subjective techniques to determine the minimum bandwidth required for clinical diagnosis of various anatomical and pathological states. In the experimental setup live ultrasound video samples representing the most common clinical examinations were compressed at 128, 256, 384, 768, 1152 and 1536 kbps using a compressor-decompressor (CODEC) adhering to International Telecommunication Union (ITU-T) recommendation H.261. A protocol for qualitative evaluation was developed and subjective and objective testing were performed based on this protocol. Subjective methods comprised of inter-rater reliability tests using kappa statistics and three way …

An Evaluation Of The Short And Long Term Effects Of Quad Helix Expansion, Sonja F. Finnie

Loma Linda University Electronic Theses, Dissertations & Projects

This study was conducted to examine, retrospectively, orthodontic and orthopedic changes resulting from quad helix expansion therapy in mixed and permanent dentition stages. Twenty-one subjects with an average age of 10.2 years who experienced an expansion of at least 3 mm with the quad helix appliance were selected for this study. The subjects were evaluated according to facial type and age for both short and long-term stability. Plaster dental casts and posteroanterior (frontal) radiographs were evaluated at the beginning of treatment (T1), at the completion of Phase 1 or full treatment (T2), and approximately two years following the completion of …

Failure Mode Of An Orthodontic Resin Alone And With Bonded Brackets, Marc Cody Dunn

Loma Linda University Electronic Theses, Dissertations & Projects

Since the introduction of bonded orthodontic brackets in the early 1960's spontaneous debonding has been a constant nemesis. Most attempts to avoid this problem by orthodontic manufactures have focused on "bond strength" issue. Whether they chose to address the materials, the bracket base or both, the common method used to evaluate improvements entailed the use of just one testing apparatus: a static universal testing machine such as the Instron.

Metal, ceramic and plastic bonded brackets were tested with the traditional shear/peel method as well as a new high strain rate impact test. The resin itself was also evaluated for physical …

An Object-Oriented Approach To The Modeling And Visualization Of Breast Cancer Tumors, Bruce C. Jenkins

Theses and Dissertations

Great strides have been made in controlling the progression of breast cancer, but medical professionals continue to rely primarily upon traditional mammography for early detection. Enhancing breast cancer detection capabilities - and thus reducing tumor detection time - should result in a reduction in mortality rates. The detection capabilities of mammography may be enhanced through improved modeling and visualization techniques. This thesis is an extension of initial research conducted at the Air Force Institute of Technology. Previous efforts focused on developing a mathematical model for simulating the growth of cancer within unconstrained 3-dimensional space. The research also explored the behavior …

Applications Of The Atomic Force Microscope Within The Fields Of Haematology And Cytogenetics, Margaret O'Reilly-Crowley

Theses

Atomic force microscopy [AFM] has become a rapidly developing interdisciplinary field of research in recent years. The technique, including instrumentation and specimen preparation methods, is now more sophisticated and its application has increased dramatically. The key advantage of AFM is in providing three-dimensional images of samples imaged. Both size and shape of samples imaged can be obtained allowing their subsequent quantification. Red blood cells [RBCs] and chromosomes were imaged in this work. A brief overview of the current status of biomedical AFM, has been presented in the review.

Measurement of mean cell volume [MCV] of immobilised red blood cells with …

The Molecular Epidemiology Of Rotavirus In Ireland, Fiona O'Halloran

Theses

Between 1997 and 1998, 3,136 cases of rotavirus diarrhoea were detected in Irish children less than 2 years of age. Hospital inpatients accounted for 80% of these infections, with the remainder being diagnosed in general practice. A large percentage of infections were detected in neonates, suggesting a possible inadequate maternal derived protection from existing indigenous strains. This feature suggested the possible existence of ‘novel’ strains circulating in Ireland. No data describing the epidemiology of rotavirus strains in this country currently exists. Furthermore no assessment of the potential health-economic impact or quantitation of potential disease burden was ever undertaken

Three hundred …