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Oral Health Inequalities In Adolescents And Young Adults In Ontario, Maria Rahman

Electronic Thesis and Dissertation Repository

Oral health is consistently linked to physiological, psychological, and social aspects of well-being in adolescents and young adults. In this thesis, I aimed to examine the social determinants of oral health and dental care utilization. First, I conducted a scoping review of the literature, demonstrated the multifaceted nature of oral health and its connections to broader social and economic factors. Then, I conducted a cross-sectional analysis of the Canadian Community Health Survey which showed a social gradient in oral health and dental care utilization among adolescents and young adults in Ontario. When stratified by age, there was a protective association …

The Significance Of Injuries And Anatomical Patterns Of Trauma In Pedestrian And Cyclist Fatalities And Their Association With Motor Vehicle Collision Dynamics And Post-Collision Kinematics, Moheem M. Halari

Electronic Thesis and Dissertation Repository

Deaths from motor vehicle collisions (MVCs) are a major global health concern, with over 1.35 million fatalities reported annually by the United Nations. More than half involve pedestrians, cyclists, and motorcyclists. Post-mortem examinations by pathologists determine the cause of death and mechanisms of injury and play a significant role in the investigation of the deaths of vulnerable road users.

The purpose of this study was to understand the injury patterns sustained by pedestrians and cyclists fatally injured in motor vehicle impacts.

This study reviews the development of injury patterns described in the medical literature and identifies their limitations in the …

The Impact Of Access To Oral Health Care On Inadequate Oral Health And Multimorbidity, Luis Limo

Electronic Thesis and Dissertation Repository

The connection between oral health and other non-communicable chronic conditions—commonly referred in the dental literature as the oral-systemic health connection—emphasizes the role of oral health care on both oral diseases and chronic conditions, particularly in vulnerable populations like the elderly. This thesis comprises 2 studies: the first is a systematic review on the impact of oral health care interventions, as an indicator of access to oral health care, on chronic conditions of which their co-existence would result in multimorbidity; the second study is a cross-sectional investigation of the associations between oral health, access to oral health care, and multimorbidity among …

Systemic, Institutional, And Teaching Factors In The Delivery Of Interprofessional Education Curriculum In Canada, Mohammad B. Azzam

Electronic Thesis and Dissertation Repository

The Canadian federal and several provincial governments are currently collaborating to establish ‘team-based’ primary healthcare—or interprofessional collaborative practice (IPCP), which can be effectively accomplished when interprofessional education (IPE) is sustainably delivered by health and social care (HASC) professional education programs. Indeed, achieving the intended patient/client-oriented outcomes of IPE and subsequent IPCP requires deliberate and purposeful considerations of several systemic, institutional, and teaching factors. Regrettably, the analyses of the extent to which these factors have influenced effective IPCP is currently under-researched. In this integrated-article dissertation, we took a purposeful and systematic approach to explore the extent to which these multi-tiered factors …

Validation Study On The Differentiation Of Human Periodontal Ligament Cells In The Presence Of Cementum Protein 1 And Periostin, Deborah A. O'Reilly

Electronic Thesis and Dissertation Repository

Existing research alludes to the fact that human periodontal ligament cells differentiate into an ossifying phenotype in response to differential gene expression during orthodontic tooth movement. The purpose of this research was to validate the differentiation of human periodontal ligament cells of young individuals in the presence of specific proteins and stimuli (cementum protein, periostin and osteogenic media), which mimic the environment of the periodontal ligament. Another objective was to assess the differential gene expression within these cells under the same conditions. A protocol was developed to provide a collagen-protein scaffold on which human periodontal ligament cells were maintained for …

Secretion Of Salivary Proteins And Their Interactions, Karla Tonelli Bicalho Crosara

Electronic Thesis and Dissertation Repository

Saliva’s clinical application for disease diagnosis and monitoring is limited by incomplete knowledge of salivary protein interactions, the effect of stimulation on the salivary proteome, and if these factors impact protein identification. This thesis expands knowledge of the salivary interactome and effects of stimulation intensity and duration on parotid saliva’s proteome. First, previous in vitro studies identified 43 proteins in the histatin 1-protein network and demonstrated histatin 1’s increased stability in whole saliva when interacting with amylase. We hypothesized that protein-protein-interaction databases could enlarge the histatin 1-protein network. A comprehensive histatin 1-protein network was created using STRING database, merging previous …

Social Determinants Of Access To Primary Care In Canada, Feben W. Alemu

Electronic Thesis and Dissertation Repository

Despite the promise of universal care, many Canadians report having unmet healthcare needs. We conducted two studies: (1) a systematic review of studies on social determinants of health (SDH) and unmet need; and (2) a secondary analysis using the Canadian Longitudinal Study on Aging (CLSA) to investigate the association of SDH and (2a) self-reported unmet need and (2b) having a family physician. The review (n=40) found a positive association between unmet need and lower income, mental health and chronic conditions, and negative association with older age, better perceived health and having a family physician. The CLSA analysis found the odds …

Determination Of The Protective Capacity Of Hand Wraps In Combat Athletes Using Force Analysis, Eva M. Gusnowski

Electronic Thesis and Dissertation Repository

Upper extremity injuries are common in combat athletes, and are highest in the hand/wrist. Although protective hand gear is used, there is a paucity of research investigating its effectiveness. This study addressed this knowledge gap by measuring the level of force transmitted to the hand during striking using two types of hand wraps. This prospective cross over study included six combat athletes. A load cell was placed over the proximal phalanges/metacarpophalangeal joints and was used to measure sustained peak force during striking while covered with either standard linear or gel-reinforced hand wraps and boxing gloves. The gel reinforced wraps consistently …

Anatomical And Functional Lung Imaging With Volumetric Computed Tomography In Non-Small Cell Lung Cancer, Heather Young

Electronic Thesis and Dissertation Repository

Non-small cell lung cancer (NSCLC) is one of the most diagnosed cancers in Canada, and the leading cause of cancer deaths. A significant challenge in treating NSCLC is balancing aggressive treatment with the potentially severe side effects. In radiation therapy, the management of respiratory motion and the risks of radiation-induced lung injury (RILI) pose significant challenges. 4-dimensional computed tomography (4D-CT) is an important part of motion management, but images often suffer from motion-induced artifacts. Volumetric CT scanners with wide axial field-of-view (aFOV) may reduce these artifacts and present an opportunity to advance CT-based functional lung imaging.

Chapter 2 presents a …

Electrochemical Deposition Of Calcium Phosphate-Based Coatings Onto Porous Ti Using Organic Phosphorus Sources, Clement Lee

Electronic Thesis and Dissertation Repository

The study and commercialization of calcium phosphate (Ca-P) coatings has occurred for several decades. However, this has typically involved the use of hydroxyapatite. This thesis presents the synthesis of different Ca-P-based coatings that has not been studied. Anodic oxidation was employed to create a porous Ti substrate, while pulsed electrochemical deposition was used to deposit the coating onto the Ti. The first coating synthesized was a calcium phosphoserine (Ca-pSer) complex, which contained two different morphologies: a flower-like structure at low deposition time and a unique cubic morphology at higher deposition times. Next, an amorphous calcium phosphate coating was synthesized and …

Extrinsic And Intrinsic Factors Influencing Homeostasis And Repair In Oral Tissues, Georgia Nikoloudaki

Electronic Thesis and Dissertation Repository

The oral tissues, including gingiva and buccal mucosa, heal rapidly with minimal scar formation. Although in the oral cavity, the palatal mucosa is associated with excessive scarring in response to injury. In this thesis, first, I investigated the complex relationship between cells and their microenvironment using wound healing models in which extracellular matrix composition and mechanical stiffness affect cellular responses during acute wound repair. I also determined how intrinsic differences of cells recruited during healing contribute to wound resolution.

In Chapter 2, I first investigated cell-extrinsic factors, specifically the influence of the pro-fibrotic matricellular protein periostin on palatal healing. Using …

Evaluating The Utility Of S100a7 In Identifying Oral Dysplastic Lesions That Will Progress To Oral Squamous Cell Carcinoma, Jeff Soparlo

Electronic Thesis and Dissertation Repository

Title: Evaluating the utility of S100A7 in identifying oral dysplastic lesions that will progress to oral squamous cell carcinoma Introduction: Recently, S100A7 has been shown to be a potential useful marker for identifying oral lesions at risk of transformation from dysplasia to squamous cell carcinoma. Our hypothesis is that high S100A7 protein expression predicts the transformation of oral epithelial dysplasia to malignancy. The objective of our study is to semi-quantitatively evaluate the level of S100A7 expression in dysplastic lesions which have transformed into oral squamous cell carcinoma using immunohistochemistry, and correlate these results with other methods of analysis including the …

Spin And Distortion In Surgical Trials, Andrea Mataruga

Electronic Thesis and Dissertation Repository

Research problem: Randomized controlled trials (RCTs) are essential; however, their validity can be threatened through distortion or spin. This study quantifies publication bias and distorted outcome reporting.

Methodology: All surgical RCTs registered on ClinicalTrials.gov from 1997-2017 were identified and a sample was obtained through random and intentional selection. Failure to publish (proportion of studies that remain unpublished), outcome distortion (changing intended outcomes), and spin (distorted presentation) were explored. Comparisons were made for positive versus negative studies and for high-income (HICs) versus low-middle income countries (LMICs).

Results: In total, 13,761 RCTs were registered (median enrollment size = 96, 94% from …

Identification Of Dna Methylation Episignatures For Classification And Phenotype/Genotype Correlation In Mendelian Neurodevelopmental Disorders, John Reilly

Electronic Thesis and Dissertation Repository

ABSTRACT: Diagnosis for neurodevelopmental disorders poses numerous challenges, related to the lack of specific findings and limited understanding of clinical impact of the majority of genetic variation. Epigenomics mechanisms involve chemical modifications in DNA that involve a range of cellular mechanisms. DNA methylation is an epigenetic mechanism involving addition and removal of methyl groups to cytosine residues. These methylation signals form episignatures; patterns of methylation that can be used as biomarkers capable of differentiating neurodevelopmental disorders. EpiSigns have enabled molecular diagnosis of a number of genetic conditions, classification of variants of unknown significance, and provided insights into the pathophysiology of …

The Effect Of Modifications To Intermaxillary Orthodontic Elastics On Force Levels And Degradation Over Time, Steven Dent

Electronic Thesis and Dissertation Repository

Introduction: Orthodontic elastics are frequently used in orthodontic treatment but there is little research into how to modify their prescription to improve their performance. The aim of this study was to evaluate potential wear modifications to a standard Class II intermaxillary elastic prescription on force levels and force degradation over time.

Methods: For this in vitro study, Ormco (OR) and American Orthodontic (AO) latex elastics had five modifications made to a standard 1/4”/4.5oz control elastic (Group 1). These included an increase of force level by one unit to 6 or 6.5oz (Group 2); a decrease in lumen size to 3/16” …

"Pain Is What The Patient Says It Is": A Secondary Analysis Of Nurses’ Reflections On The Term Pain Catastrophizing, Riana Longo

Electronic Thesis and Dissertation Repository

Background: Pain catastrophizing is a widely used concept; however, many have argued that it delegitimizes and decontextualizes patients’ pain experiences. Previous studies identified that patients and clinicians think the term is stigmatizing; however, nurses’ perceptions are underrepresented. Nurses offer a unique perspective that is critical to explore to foster positive change and improve patient outcomes. Objectives: This thesis aims to summarize the current literature on pain catastrophizing perspectives from clinicians and patients, analyze nurses’ perspectives, and uncover any underlying issues with the term itself. Methods: This thesis consisted of a two-stage design. The first study is a scoping review that …

Cost-Effective Non-Destructive Testing Of Biomedical Components Fabricated Using Additive Manufacturing, Santiago Fabian Cobos

Electronic Thesis and Dissertation Repository

Biocompatible titanium-alloys can be used to fabricate patient-specific medical components using additive manufacturing (AM). These novel components have the potential to improve clinical outcomes in various medical scenarios. However, AM introduces stability and repeatability concerns, which are potential roadblocks for its widespread use in the medical sector. Micro-CT imaging for non-destructive testing (NDT) is an effective solution for post-manufacturing quality control of these components. Unfortunately, current micro-CT NDT scanners require expensive infrastructure and hardware, which translates into prohibitively expensive routine NDT. Furthermore, the limited dynamic-range of these scanners can cause severe image artifacts that may compromise the diagnostic value of …

Torque Expression Of Active And Passive Self-Ligating Orthodontic Brackets With Different Stainless Steel Wire Sizes, Jennifer L. Boogaards

Electronic Thesis and Dissertation Repository

This investigation aimed to compare engagement angles and torquing moments generated by stainless steel (SS) wires in three active self-ligating (ASL), one passive self-ligating (PSL), and a conventional twin orthodontic bracket system control. Brackets were tested in simulations of buccal and palatal root torque using four sizes of SS wires (16x22, 17x25, 19x25, 20x20 mil). A custom 3D printed testing apparatus was developed to measure torque. After initial engagement within bracket slots, torquing moments increased with progressive rotation of brackets around wires. In general, the PSL and conventionally ligated systems generated significantly larger torquing moments than ASL systems, especially with …

Validation Of The Flexcell®Fx-5000 Tension System To Evaluate The Expression Of Cementum Protein-1 In Human Periodontal Ligament Cells While Under Cyclical Orthodontic Tensile Force, Allison Nicholls

Electronic Thesis and Dissertation Repository

The pressure-tension theory of orthodontic tooth movement (OTM) states that there are differences in microenvironment between the tension and compressions side within the periodontal ligament, leading to differential gene expression within those zones. Cementum protein 1 (CEMP-1) is a human-specific protein localized to the root of a tooth and may play a role in OTM. The first objective was to develop a protocol to apply tensile force to human PDL cells similar to that within the tension zone during OTM. For this, the FlexCell®FX-5000 Tension system was used and fluorescent microscopy was used to confirm validity of the protocol. The …

Health Care Utilization By Immigrants With Multimorbidity: A Population Based Cross-Sectional Study Of The 2015-2016 Canadian Community Health Survey (Cchs), Chinmoy Talukder

Electronic Thesis and Dissertation Repository

Immigrants face unique healthcare barriers, which can negatively impact their health and health service use. Those with multimorbidity face a particular challenge as multimorbidity is associated with increased need for healthcare. The purpose of this study was to compare healthcare utilization, as measured by number of visits to family physicians and specialists, between immigrants and Canadian-born populations with multimorbidity, stratified by sex and for specific chronic diseases. A cross-sectional analysis using 2015-2016 Canadian Community Health Survey (CCHS) was conducted. After adjusting for relevant covariates, no statistically significant differences in visits to family physicians or specialists were observed between immigrants and …

Investigating Bone Cement Susceptibility Related Artifacts And Adhesion, Eric Kuindersma

Electronic Thesis and Dissertation Repository

Blood Oxygen Level Dependent (BOLD) functional Magnetic Resonance Imaging (fMRI) utilizes pulse sequences sensitive to changes in concentration of deoxyhemoglobin to indirectly measure neural activity. Sequences used for BOLD are sensitive to magnetic susceptibility differences that may cause signal voids. Our lab has designed an awake marmoset head coil that eliminates confounds associated with imaging an animal under anesthesia. This design requires a head chamber attached to an animal’s skull with a cement that may cause a susceptibility artifact. Motivation behind this project was to find an MRI compatible cement that remains secure to the skull with minimal artifacts. Four …

Gender-Based Violence Among Women And Girls With Disabilities In Sub-Saharan African Countries: A Scoping Review Of The Literature, Aimée Josephine Utuza

Electronic Thesis and Dissertation Repository

Despite numerous studies about gender-based violence (GBV) in Sub-Saharan Africa (SSA), little attention has been paid to violence against women and girls with disabilities. Thus, this scoping review provides an overview of the empirical literature on GBV and disability within the SSA context. Selected literature included various aspects of GBV epidemiology, prevention and response, and interventions. Other aims were to identify the gaps in the current knowledge base and to contribute to an evidence-informed framework for the development of relevant and holistic programs and policies. A key finding is that efforts to seek help are often hampered by barriers, stigmatization, …

Erythrokeratodermia Variabilis Et Progressiva (Ekvp) Linked Cx30.3 Mutants Can Be Selectively Rescued By Co-Expression Of Wildtype Keratinocyte Connexins, Rhett O. Figliuzzi

Electronic Thesis and Dissertation Repository

Connexin 30.3 (Cx30.3) is a β-connexin encoded by GJB4 that is key in epidermal homeostasis. Eleven mutations to the GJB4 are linked to an autosomal dominant skin disease called erythrokeratodermia variabilis et progressiva (EKVP). These mutations remain largely uncharacterized, limiting therapeutic options. In this study, we characterize the expression and functional status of three EKVP-linked Cx30.3 mutants, G12D, T85P and F189Y in rat epidermal keratinocytes. We found that EKVP-linked Cx30.3 mutants were not functional due to their retention in the endoplasmic reticulum (ER), but did not upregulate BiP, an indicator of ER stress. Sub-physiological incubation and chemical chaperones (such as …

The Antimicrobial Properties Of Exogenous Copper In Human Synovial Fluid Against Staphylococcus Aureus: An In-Vitro Study, Fernando Diaz Dilernia

Electronic Thesis and Dissertation Repository

We sought to analyse the antimicrobial properties of exogenous copper in human synovial fluid against Staphylococcus aureus. We performed several in-vitro growth and viability assays to determine the capability of multiple S. aureus strains to survive in synovial fluid under different growth conditions. S. aureus UAMS-1 significantly died at 24 hours (p=0.017), and S. aureus USA300 WT survived at 24 hours. We confirmed a high sensitivity to killing with the addition of exogenous copper on both strains at 4 (p=0.011), 12 (p=0.011), and 24 hours (p=0.011). Both WT and CopAZB-deficient USA300 strains significantly died in synovial fluid, evidencing a …

Functional Performance Testing In Ice Hockey: The Role Of The Single Leg, Medial Countermovement Jump, Anthony S. Donskov

Electronic Thesis and Dissertation Repository

Due to the physical nature of the game, injuries are common in ice hockey. Injury rates have been difficult to interpret due to the inconsistencies in the definitions of injury and athlete exposure. Consensus statements on injury definitions have been developed for sports such as soccer and rugby but have not been established in ice hockey. Furthermore, many different off-ice tests are performed, but a hockey-specific performance test has not been promoted. Accordingly, the objective for this thesis was to investigate injury rates, injury definition, athlete exposure and injury type in men’s ice hockey, and providing information on a practical …

Descriptive Analysis Of Fall-Related Injuries Among Older Adults In Ontario, Nicolette Lappan

Electronic Thesis and Dissertation Repository

Falls are the leading cause of injury-related hospitalizations among older adults in Canada. The purpose of this study was to describe the characteristics of older adults who experienced fall-related injuries (FRIs) and the types of falls that caused them. We analyzed Ontario-wide secondary data from three databases (NACRS, DAD, RPDB) covering 2010-2014. Older adults (≥ 65 years) who visited emergency departments (ED) with FRIs were selected using ICD-10-CA codes for a fall and injury. Counts, measures of central tendency, and prevalence rates (crude, age- and sex-specific, age-standardized) were calculated. There were 304,610 (63.0% females) ED admissions (3,089 per 100,000 population) …

Catechol-Containing Copolymers As An Active Ingredient For Denture Adhesives, Vincent Ying Wun Kong

Electronic Thesis and Dissertation Repository

Moisture inside the mouth adds challenge to making denture adhesives formulations. Some formulations have zinc to enhance adhesion on wet skin despite knowing the health hazards. Inspired by mussel foot proteins’ catechol unit’s strong underwater adhesion, nine catechol-containing copolymers (P1A-P3C) were synthesized by free radical polymerization of 3,4-dimethoxystyrene (3,4- DMS) with different styrene derivatives followed by deprotection. P1A-P3C were used to make Fn(P)-C-PBS denture adhesive formulations which had suitable shear stresses around ≥ 5 kPa satisfying ISO 10873. In-situ NMR studies of free radical polymerization of 3,4 - DMS and styrene derivatives allowed computation of their reactivity ratios showing all …

Syrian Refugee Women's Experiences With The Ontario Health Care System: A Critical Ethnography Study, Areej Al-Hamad

Electronic Thesis and Dissertation Repository

There has been growing interest in migration and refugee research; the vulnerability of Syrian refugee women and how they adapt to their host communities. However, there is limited evidence regarding the pre- and post-migration trauma and its impacts on the health of Syrian refugee women in the Canadian context. The purposes of this critical ethnography using intersectional perspectives were: (1) to explore and describe Syrian refugee women’s experiences and meanings of pre- and post-migration trauma and its impact on their health in the context of repeated displacement and migration from their homes and families; (2) to critically examine how the …

A Critical Review And Finite Element Study Of Structural Relaxation In Veneered 3y-Tzp Dental Structures, Prashant S. Shelar

Electronic Thesis and Dissertation Repository

Yttria stabilized Tetragonal Zirconia Polycrystal (3Y-TZP) materials veneered with porcelain are preferred for clinical practice due to their bio-functionality, biocompatibility, and affordability. However, these materials are often subjected to premature clinical failures due to combination of subsurface flaws and tensile stresses within porcelains. This work focuses on performing a critical literature review and evaluating veneer characteristics, i.e. structural relaxation, to form a suitable explanation for the development of subsurface stresses. User material subroutines, UEXPAN and UTRS are developed, validated and integrated in ABAQUS finite element solver. With the use of validated models, it is shown that faster cooling rates and …

Characterizing The Anxiolytic Potential And Synergistic Efficacy Of Cannabidiol And D-Limonene, Nathashi Jayawardena

Electronic Thesis and Dissertation Repository

Emerging evidence has elucidated the anxiolytic properties of the cannabis-derived phytochemicals cannabidiol (CBD) and d-limonene and the ‘Entourage Effect’ wherein, multiple components of cannabis synergize to produce stronger effects than their pure counterparts. However, no studies have yet explored this effect in combinations of CBD and limonene. Thus, the present thesis investigated the anxiolytic and synergistic potential of concurrently administered intra-nucleus accumbens shell CBD (1 ng/0.5 μl or 5 ng/0.5 μl) and inhaled limonene (200 μl or 2000 μl). Additionally, the role of the 5-HT1A receptor in mediating these effects was examined by co-application of the antagonist NAD299 and by …