Dentistry Commons^™

Genetically Engineering Gingipains For High Yield Large Scale Purification., Andrew E. Fuchs

Electronic Theses and Dissertations

Porphyromonas gingivalis is a keystone oral pathogen in the progression of periodontal disease and has been implicated in the etiology of many other systemic human diseases. P. gingivalis produces primary virulence factors termed the gingipains, a group of cysteine proteases. There is a high demand for high purity gingipains for downstream in vitro studies where P.g. is implicated, both oral and systemic. Gingipain production candidate mutant P.g. strains were generated to isolate each gingipain for large scale purification and the purified gingipains characterized. Two mutants were determined not to be viable for large scale purification of gingipains, each for different …

Enhancing Adherence To Best Practice Guidelines Related To Pressure Injury Prevention In The Operating Room At A Children's Hospital During Comprehensive Dental Procedures., Alyce Bailey Seaver

Doctor of Nursing Practice Papers

Background: 1,600,000 patients develop a hospital-acquired pressure injury every year, and 23% of these originate during surgery. Research has demonstrated that the incidence of hospital-acquired pressure injuries developing during surgery has risen over the past 5 years. This rise has been attributed to nurse circulators exhibiting poor knowledge regarding best practices for intraoperative patient positioning and intraoperative documentation that does not follow standards of care.

Purpose: This quality improvement project aimed to enhance circulator knowledge on best practices for intraoperative patient positioning and improve documentation of intraoperative patient positioning in the electronic medical record to comply with standards of …

The Emerging Oral Pathogen, Filifactor Alocis, Modulates Antimicrobial Responses In Primed Human Neutrophils., Ian J. Snider

College of Arts & Sciences Senior Honors Theses

Periodontitis is an irreversible, chronic inflammatory, infectious disease of the oral cavity that affects approximately half of all adults 30 years or older in the USA. The oral cavity is under high immune surveillance because of its constant exposure to microbes in the environment. The primary immune cell responsible for this surveillance is the neutrophil. Pathogens associated with periodontitis possess virulence factors and have evolved strategies to evade neutrophil antimicrobial responses to survive. One such pathogen is Filifactor alocis, whose presence is associated with the progression of periodontitis. F. alocis manipulates several neutrophil antimicrobial functional responses to avoid killing, an …

Aggregatibacter Actinomycetemcomitans Exploits And Modulates The Immune Response By Human Neutrophils For Survival In The Anaerobic Environment., Hazel Ozuna

Electronic Theses and Dissertations

Aggregatibacter actinomycetemcomitans (Aa) is a Gram-negative facultative anaerobe and an opportunistic oral pathogen, strongly associated with localized periodontitis and other inflammatory diseases. Periodontitis is a chronic inflammation of the periodontium resulting from the inflammatory response of the host towards the dysbiotic microbial community present at the gingival crevice. The host immune response creates a hostile environment for microorganisms; therefore, it is important for Aa to be able to regulate the necessary genes to survive and thrive in such an environment. Aaexpresses several virulence factors such as a cytolethal distending toxin (Cdt), lipopolysaccharide (LPS) and leukotoxin A (LtxA), …

Predicting Dental Student's Performance On National Board Dental Examination (Nbde) Part I: Exploring Demographic Factors, Dental Admission Test (Dat) Factors, Pre-Program Academic Factors, And Dental Program Academic Performance., Wei-Shao Lin

Electronic Theses and Dissertations

Dental students need to successfully challenge a national licensure examination to be able to practice dentistry. Dental educators currently have difficulty in identifying candidates who are at risk of failing this examination. This non-experimental quantitative study examined existing dental student data from the 2017, 2018, and 2019 graduating classes, using a retrospective and correlational approach to identify possible markers for at risk students. Demographic factors, dental admission test (DAT) factors, pre-program academic factors, dental program academic performance, and National Board Dental Examination (NBDE) Part I performance. A series of independent t-tests and One-Way analysis of variances (ANOVAs) were used to …

Epithelial Responses To Porphyromonas Gingivalis In The Community Context., Zackary Ray Fitzsimonds

Electronic Theses and Dissertations

Porphyromonas gingivalis, a keystone pathogen for periodontal disease, initiates a complex molecular dialogue with gingival epithelial cells, leading ultimately to disruption of host signaling pathways. Dysbiotic host responses are also thought to contribute to the initiation and progression of oral squamous cell carcinomas. Recently, the homeostatic commensal Streptococcus gordonii has been shown to antagonize P. gingivalis-induced epithelial cell signaling events in host cells, such as proliferation and migration. The aim of this study was to characterize pathways that P. gingivalis targets to disturb host signaling, with a specific focus on pathways that S. gordonii can restore to homeostatic …

Application Of Machine Learning Technologies For Detection Of Proximal Lesions In Intraoral Digital Images: In Vitro Study., Rohit Vadlamani

Electronic Theses and Dissertations

Background: Interpretation of bitewing radiographs is influenced by factors such as acquisition parameters (e.g. exposure, type of sensor), clinical technique, visualization (e.g. monitor type and calibration) and the observer (e.g. experience and fatigue bias). We hypothesized that the use of artificial intelligence (AI) will reduce visualization and observer factor in bitewing interpretation and improve diagnostic accuracy. Objective: The purpose of the present study was to evaluate the use of AI in the form of a machine-learning algorithm to detect and quantify proximal lesions compared with human trained observers. Methods: 16,000 anonymized, digital bitewings of patients were hand searched and non-bitewing, …

The Emerging Oral Pathogen, Filifactor Alocis, Disrupts Neutrophil Functions To Enhance Survival And Dysregulate Inflammation., Irina Miralda Molina

Electronic Theses and Dissertations

Periodontitis is an irreversible, chronic inflammatory disease where pathogenic microbial communities accumulate in the gingival crevice. Advances in culture-independent techniques have facilitated the identification of new bacterial species in periodontal lesions, such as the Gram-positive anaerobe, Filifactor alocis. Neutrophils are a major component of the innate host response, and the outcome of their interaction with F. alocis may be a determinant of oral health status. While neutrophil functions typically protect the host against periodontal disease, oral pathogens have adapted to evade or disarm neutrophil microbicidal functions while promoting mechanisms that drive inflammation, which also provides a source of nutrients …

Functionalizing Nanoparticles With Cafa Protein To Target Bar Peptide For Oral Delivery Applications., Hetal Desai

Electronic Theses and Dissertations

Background: Porphyromonas gingivalis adherence to Streptococcus gordonii may be important for P. gingivalis colonization in the oral cavity. Nanoparticles encapsulating synthetic peptide BAR (BAR-NPs) inhibit P. gingivalis adherence more potently than free BAR. However, BAR-NPs would exhibit low retention in an open flow environment. Hypothesis: Targeting BAR-NPs to the streptococcal surface using CafA protein will enhance their efficacy. Methods: CafA-modified NPs encapsulating BAR were synthesized using double emulsion approach. Surface binding and retention, and release kinetics of BAR from CafA-modified NPs was assessed. Functional inhibition assays were performed using dual a species biofilm. Results: CafA-modified NPs demonstrated specificity of adhesion, …

Tobacco Enhances Bacterial-Induced Periodontal Bone Loss In Mice., Mina Iskander

Electronic Theses and Dissertations

Background: Tobacco smoking is the leading environmental risk factor for periodontal diseases. Delineation of the mechanisms underlying tobacco-induced or exacerbated periodontitis is hampered by the lack of an appropriate and reliable animal model. Hypothesis: We hypothesized that Porphyromonas-gingivalis-infected, cigarette smoke-exposed mice would represent reproducible models of acute (ligature model) and chronic (oral gavage model) tobacco-enhanced periodontitis that reflect multiple aspects of the disease noted in human smokers. Methods: In a chronic oral gavage disease model, Balb/c mice (6-8 weeks, 4 groups of n = 6 per group) were exposed to smoke produced by a Teague-10 smoking machine from 1R6F research …

Oral Health-Related Quality Of Life In Us Adults With Type 2 Diabetes., Giang Truong Vu

Electronic Theses and Dissertations

This dissertation focused on the relationship between type 2 diabetes (T2DM) and oral health-related quality of life (OHRQoL) and the factors associated with this relationship in the US. The objectives of the dissertation research were a three-part process: (1) to understand the relationships of T2DM with poor OHRQoL, clarify risk and preventive factors that affect this association, and identify research gaps in the literature, (2) to analyze risk factors associated with poor OHRQoL in US adults with T2DM using a nationally representative random probability cluster sample, and (3) to apply structural equation modeling (SEM) to a simplified Andersen’s Behavioral Model …

Transcriptional Influence Of Retinoic Acid And Its Effects On Angiogenesis Of Murine Salivary Glands., Isaac Feinn

College of Arts & Sciences Senior Honors Theses

Salivary gland hypofunction is a major disorder of salivary glands, and can arise either from diseases such as xerostomia, or from defective epithelial morphogenesis during embryogenesis. Hundreds of thousands of individuals suffer from dry mouth, and there is currently no restorative therapy for these patients. Investigation of salivary gland developmental biology will inform regenerative therapies. Currently it is known that retinoic acid (RA), the biologically active form of Vitamin A, is required for proper development of the salivary gland, but little is known about its cellular mechanism regulating organogenesis. This study sought to analyze salivary gland development in Rdh10 knock …

Marginal Staining Between Pressed Lithium Disilicate Ceramic Crowns And Direct Restorative Materials By Various Fluids : A Microleakage Study., Sarah Ann Jestel

Electronic Theses and Dissertations

When treating patients with existing restorations in which indirect restoration placement is indicated and crown lengthening surgery is contraindicated, dentists may choose to finish the crown margin on an existing restoration. The interface between the two dental restorations (resin composite and ceramic crown) may be more susceptible to microleakage and fluid staining, reducing restoration longevity. In this study, 80 extracted molars received indirect restoration margins finished on different direct restorative materials (resin-modified glass ionomer and conventional, flowable, and bulk fill nano-hybrid resin composite) and subjected to common staining fluids of coffee, tea, red wine, or Coca-Cola. If the clinician must …

Development Of Bar-Peptide Nanoparticles And Electrospun Fibers For The Prevention And Treatment Of Oral Biofilms., Mohamed Yehia Mahmoud

Electronic Theses and Dissertations

Background: Periodontal diseases are globally prevalent inflammatory disorders that affect ~47% of U.S adults. Porphyromonas gingivalis (Pg) has been identified as a “keystone” pathogen that disrupts host-microbe homeostasis and contributes to the initiation and progression of periodontitis. Pg associates with oral streptococci in supragingival plaque and this interaction represents a potential target for therapeutic intervention. Previously our group developed a peptide (designated BAR), that potently inhibits Pg/Streptococcus gordonii (Sg) adherence in vitro and Pg virulence in a murine model of periodontitis. While efficacious, BAR (SspB Adherence Region) provided transient inhibition and required higher concentrations of BAR to disrupt established …

The Q Rule In Bacteriodetes And The Identification And Characterization Of Porphyromonas Gingivalis Glutaminyl Cyclase., John Andrew Houston

Electronic Theses and Dissertations

Background: Porphyromonas gingivalis, a major pathogen associated with chronic periodontitis, secretes variety of proteins, majority of which begins with glutamine. Several of these proteins were found with pyroglutamate (pGlu) at N-terminus suggesting the presence of this posttranslational modification pathway in P.gingivalis. The observation that N-terminal glutamine is over-represented as the first amino acid after signal peptide cleavage, and subsequent confirmation of pGlu formation on the nascent protein via mass spectrometry, led us to conclude that an enzyme must be present as the executor of this reaction. Hypothesis: PG2157 is a glutaminyl cyclase and is responsible for the cyclization of …

Synthesis And Characterization Of Targeted Bar Encapsulated Polylactic-Co-Glycolic Acid Nanoparticles To Inhibit Porphyromonas Gingivalis Biofilm Formation., Ranjith Radha Krishnan

Electronic Theses and Dissertations

Periodontal disease is one of the most prevalent infectious diseases worldwide. Between 30-50% of the global adult population suffers from periodontal disease. Some form of periodontitis is present in 46% of American adults, corresponding to annual expenditures in excess of 14 billion dollars for treatment and prevention. Current treatments for periodontal diseases involve mechanical removal of plaque, correction of risk factors, gingival surgery and/or antibiotic therapy. To our knowledge there is no effective therapeutic approach that aims to limit pathogen colonization of the oral biofilm or re-colonization after treatment. Interaction of the pathogen Porphyromonas gingivalis with oral streptococci is critical …

Effect Of Grape Components On Periodontal Disease., Juili Subodh Shivde

Electronic Theses and Dissertations

Background: Half of the adult American population (47 %) are victims of periodontitis, a chronic inflammatory disease which leads to destruction of the tissues supporting the tooth. Periodontitis is initiated by periodontal pathogens and caused by excessive or prolonged host mediated inflammation. Porphyromonas gingivalisis one important agent implicated in the etiopathogenesis of chronic periodontitis. Pro-inflammatory cytokines induced by periodontal pathogens can cause alveolar bone loss and periodontitis. Bone loss is caused by the imbalance of bone formation and bone resorption. Osteoclasts are major cells that cause bone resorption. Moreover, periodontal inflammation also leads to bone resorption. Grapes are rich …

Influences Of Porphyromonas Gingivalis On The Viability Of Esophageal Cancer Cells., Muddasir Mohammed

Electronic Theses and Dissertations

A recent study demonstrated an association between the Porphyromonas gingivalis (Pg)infection and the progression of ESCC (Gao et al., 2016). However, how Pg infection affects the nature of ESCC remains unknown. We examined the effects of Pg on the proliferation and chemotherapy drug-induced apoptosis of ESCC cells and elucidated the signaling molecules involved in these processes. Method: Apoptosis and cell proliferation were tested using Flow cytometry and Tetrazolium salt based proliferation assays respectively. Western Blot was utilized to detect the protein expression. CDK2 and Cyclin E were knocked down in the ESCC cells through transfection. Unpaired T-test and …

Cannabidiol Alters The Immune Response To Porphyromonas Gingivalis In Mice., Shilpa Singh

Electronic Theses and Dissertations

Background: Porphyromonas gingivalis is an important etiologic agent of chronic periodontitis, an infectious disease defined by destruction of supporting tissues of the teeth. Marijuana is a risk factor for chronic periodontitis, although underlying mechanisms are poorly understood. As phytocannabinoids have been ascribed antiinflammatory properties, we hypothesized that cannabidiol exposure would lead to altered immune response to P. gingivalis infection facilitating bacterial persistence and, subsequently, increased alveolar bone loss in cannabidiol (CBD)-exposed mice. Methods: P. gingivalis-infected cannabinoid receptor 2 (CB2) knockout and wild type C57/Bl6 mice were exposed, or not exposed, to cannabidiol. Oral swabs from mice were used to monitor …

Long-Term Dental Outcomes Of The Professional Education Preparation Program., Samuel D. Petersen

Electronic Theses and Dissertations

Introduction: The Professional Education Preparation Program (PEPP) is a health careers pipeline program for Kentucky pre-health students from Health Professional Shortage Area counties and/or racial/ethnic groups underrepresented in the health professions. The purpose of this study was to determine the demographics of the dental PEPP participants and if, post dental school graduation, they were providing care for underserved patient populations Methods: PEPP dental graduates (n=114) had been previously identified. Participants were contacted by phone, asked to participate and then mailed a survey. Survey questions covered personal, practice and patient characteristics, procedures performed, insurance accepted and community outreach. Logistic regression analysis …

Effect Of Porcelain Thickness And Translucency On The Final Shade Of Ips E.Max Cad Overlaying A Dark Substrate., Peter F. Alena

Electronic Theses and Dissertations

IPS e.max is a very esthetic lithium disilicate used in dental ceramics. Unfortunately, it can unintentionally change color after cementation with resin cements. The purpose of this study is to better understand how combining thickness and translucency affects the post-cementation shade of IPS e.max CAD overlaying a dark substrate, thereby enabling clinicians to choose more appropriate techniques and materials. IPS e.max CADs (A1 shade) had either a low translucency (LT) or high translucency (HT), and cut with 0.3mm, 0.5mm, and 1.0mm thicknesses. Each sample overlaid a resin cement and dark substrate, a spectrophotometer helped derive the color difference (ΔE*ab), and …

Intraoral Imaging At Insertion Of Implant Supported Restorations At An Academic Institution : Conformity To Established Guidelines., J. Alec Power

Electronic Theses and Dissertations

The objective of this study was to establish the frequency of intraoral imaging at the time of insertion of implant supported restorations at University of Louisville School of Dentistry (ULSD). After IRB approval (14.1215), patients on whom an implant-supported single unit fixed restoration was placed were identified from the electronic health record over a 4-year period. Type of prosthesis retention (cement vs. screw) and discipline responsible for crown placement was recorded. Bitewing (BWx) or periapical (pa) images taken at the time of prosthesis placement were accessed and reviewed. Overall radiographic frequency according to modality was tallied and compared using Chi-square …

Development Of Blended Polymeric Fibers To Alter The Release Of Peptide Targeting Porphyromonas Gingivalis., Sonali Suresh Sapare

Electronic Theses and Dissertations

Periodontitis is a chronic inflammatory disease that infects the tissues of the periodontium. It is estimated that 47.2% or 67.2 million American adults suffer from mild, moderate and severe periodontitis. Globally, 30-50% of the adult population is afflicted with periodontal disease, making it one of the most prevalent infectious diseases in the world. Therapeutics targeting P. gingivalis may be effective to alter periodontitis progression. However, the current treatment modalities that target critical pathogens to maintain host-biofilm homeostasis are limited, urging the development of specifically targeted therapeutics to limit P. gingivalis recolonization of the oral cavity after periodontal treatment and healing. …

Deficiency Of Rdh10 Causes Cleft Secondary Palate In Mouse., Swetha Raja

Electronic Theses and Dissertations

The focus of this project is to understand the role of Retinoic Acid (RA) produced by RDH10-mediated metabolism of Vitamin A in palate development. For 80 years now, we have known that dietary restriction of RA/Vitamin A can cause cleft palate but we have failed to understand how RA deficiency causes cleft palate. Our gap in knowledge about how RA deficiency causes cleft palate is mainly owing to the fact that we lack a model system to study such defects. The aim of this thesis research project was to determine if conditional inactivation of the Vitamin A metabolic gene Rdh10 …

The Role Of Kinases And Phosphatases In The Pathobiology Of Porphyromonas Gingivalis., Sarah Whitmore

Electronic Theses and Dissertations

Periodontal diseases result from the interplay between the dysregulation of the host inflammatory response and the actions of a dysbiotic bacterial community. These chronic inflammatory conditions affect persons on a worldwide scale. P. gingivalis is strongly implicated as a key periodontal pathogen in the more severe manifestations of periodontal diseases such as periodontitis. A core element of P. gingivalis pathogenicity is its dysregulation of innate immunity, including suppression of IL-8 production by gingival epithelial cells. The NF-κB family of related transcription factors plays a central role in regulating many important aspects of innate immune responses. NF-κB RelA/p65 homodimers regulate transcription …

Type Ix Secretion System : Characterization Of An Effector Protein And An Insight Into The Role Of C-Terminal Domain Dimeration In Outer Membrane Translocation., Lahari Koneru

Electronic Theses and Dissertations

Porphyromonas gingivalis and Tannerella forsythia are two of the primary pathogens that are associated in the etiology and progression of chronic periodontitis. In T. forsythia, KLIKK proteases are the recently identified group of proteolytic enzymes that are secreted through Type IX secretion system (T9SS). Among, these KLIKK proteases a synergistic relationship was observed between karilysin and mirolysin in invading the host complement system for the survival of the bacteria. Since, karilysin has been already characterized, in this study we propose to study about mirolysin through structural, biochemical and biological characterization. The obtained results from the experiments has shown the …

Cumulative Trauma, Emotion Reactivity And Salivary Cytokine Response Following Acute Stress Among Healthy Women., Yvette Z. Szabo

Electronic Theses and Dissertations

This study furthers understanding of how trauma exposure may be connected to the development and maintenance of poor health by focusing on cytokines, tightly regulated proteins of the immune system. Cytokine responses to acute stress have been associated with the onset of poorer mental health in physically healthy women. The present study examined how two factors recently associated with cytokine reactivity –cumulative trauma and emotion reactivity– are associated with salivary cytokine reactivity among healthy women. Seventy-one women, screened to be physically and mentally healthy, completed a laboratory acute stress paradigm and self-report measures of state emotion and trauma exposure. Participants …

Using An Audience Response System To Calibrate Dental Faculty Assessing Student Clinical Competence., Sean A. Aiken

Electronic Theses and Dissertations

In order to best prepare students to become competent and confident practitioners in a clinical environment upon graduating dental school, it is imperative for them to receive consistent and productive feedback from the supervising faculty. Through academic engagement, and more specifically faculty calibration, it may be possible to eliminate the disconnect that sometimes exists between faculty expectations and terminology, and those of the students. In terms of definitions, academic engagement reflects faculty scholarly development activities that support integration of relevant, current theory of best practices consistent with the school's mission, expected learner outcomes, and supporting strategies.1-6, 32 The difficulty lies …

Treg Regulation In Periodontal Disease During Pregnancy., Aislinn Leah Hays

Electronic Theses and Dissertations

Background: Although pregnancy is prone to induce more severe periodontal inflammation and tissue damage, its mechanism remains elusive. Periodontal diseases during pregnancy are associated with adverse pregnancy outcomes including preterm birth or low birth weight. Animal models are ideal for investigating immunological mechanisms in periodontal disease. With a newly modified ligature-induced disease model, we managed to develop periodontal disease in pregnant mice and investigate the immunological mechanism of more severe symptoms during pregnancy. Hypothesis: We hypothesis that P. gingivalis infection during pregnancy will lead to a down-regulation of Treg cells, therefore causing increased inflammation and disease severity. Methods: A ligature-induced …

Exploring A Novel Nf-ĸb- Inhibiting Nanoparticle For Periodontitis Therapy., Kameswara Satya Srikanth Upadhyayula

Electronic Theses and Dissertations

Periodontitis is an infection-driven inflammatory disease characterized by gingival inflammation and bone loss. The NF-ĸB signaling pathway is pivotal in osteoclastogenesis and infection-induced pro-inflammatory responses. The use of nanoparticles as a vehicle to deliver drug increases stability, loading capacity, and facilitates transmembrane transportation. The hypothesis was that a novel nanoparticle carrying therapeutic NBD inhibitory peptides (NBD-nanoparticles) will inhibit measures of periodontal disease. In this project, we tested the nanoparticles for their ability to directly inhibit osteoclastogenesis and inflammation as an original strategy for periodontitis therapy. We also tested the capability of the nanoparticles to inhibit gingival inflammation and alveolar bone …