Medicine and Health Sciences Commons^™

Differential Effects Of Extracellular Matrix Glycoproteins Fibronectin And Laminin-5 On Dental Pulp Stem Cell Phenotypes And Responsiveness, Hyungbin Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Dental pulp stem cells (DPSCs) are mesenchymal stem cells (MSCs) with the potential to differentiate in a limited number of other tissue types. Some evidence has suggested the modulation of DPSC growth may be mediated, in part, by exogenous extracellular matrix (ECM) glycoproteins, including fibronectin (FN) and laminin-5 (LN5). Although preliminary research suggests that some ECM glycoproteins may work as functional biomaterials to modulate DPSC growth responses, the primary goal of this project is to determine the specific effects of FN and LN5 on DPSC growth and viability.Using an existing DPSC repository, n = 16 DPSC isolates were cultured and …

Dental Pulp Stem Cell Differentiation Potential Of Bmp-2 And Bmp-4, David Li

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: Many studies are now evaluating the potential for dental pulp stem cells (DPSC) to assist with more complex and biotechnology applications, such as facilitating and promoting osseointegration following dental implants. However, the effects of factors that may control osseointegration and bone repair using DPSC including bone morphogenic proteins (BMP-2, BMP-4) are not yet well understood.Objective: Based upon this lack of evidence, the primary goal of this project is to evaluate the potential effects of BMPs (alone or in combination with other growth factors) to induce factors associated with osteogenesis. Methods: DPSC isolates from an existing repository (n = 13) …

Chemotherapeutic Drug Resistance Associated With Differential Mirna Expression Of Mir-375 And Mir-27 Among Oral Cancer Cell Lines, Kieran Huni

UNLV Theses, Dissertations, Professional Papers, and Capstones

Objective: Although progress has been made towards the identification of molecular profiles that influence oral cancer growth and metastasis, recent advances have suggested that non-coding microRNAs (such as miR-21, miR-27, miR-145, miR-155, miR-365, miR-375 and miR-494) may be involved in multiple aspects of chemotherapeutic responsiveness. Based upon the paucity of information regarding this phenomenon, this project will determine whether these specific microRNAs are correlated with oral cancer responsiveness to chemotherapies, including Paclitaxel, Cisplatin and Fluorouracil (5FU).Methods: Commercially available and well-characterized oral squamous cell carcinoma cell lines (SCC4, SCC9, SCC15, SCC25 and CAL27) were used for this study. Experimental 96-well assays …

Oral Prevalence Of Akkermancia Muciniphila Among Pediatric And Adult Orthodontic And Non-Orthodontic Patients, Ching Shen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Akkermansia muciniphila (AM) is one of many highly abundant intestinal microbes that influences homeostasis and metabolic disorders and may also play a role in oral disorders. However, there is little evidence regarding the oral prevalence of this organism. Based upon this lack of evidence, the primary goal of this project is to survey an existing saliva repository to determine the overall prevalence of this organism and any associations with demographic or patient characteristics (age, sex, body mass index, race/ethnicity, orthodontic therapy). Using an approved protocol, a total n = 141 pediatric samples from an existing saliva repository were screened using …

Comparative Expression Of Exosome-Derived Dental Pulp Stem Cell (Dpsc) Microrna, Matthew Hunsaker

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: Dental pulp stem cells (DPSC) are pluripotent stem cells capable of differentiating into several tissue types. Several studies have demonstrated DPSC can be extracted from deciduous and permanent teeth, including third molars (wisdom teeth) - however, much less is known regarding the factors that determine and regulate pluripotency and differentiation responsiveness among these harvested DPSC. Recent evidence has suggested small, non-coding microRNAs mediate (in part) differentiation and self-renewal among some stromal and hematopoetic stem cells, although much remains to be discovered regarding microRNA regulation of DPSC phenotypes. Based upon this information, the overall goal of this study was to …

Differential Expression Of Cellular And Exosomal Microrna Isolated From Oral Cancer Cells And Their Resistance To Chemotherapy, Brady Petersen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: MicroRNAs are abundant small non-coding RNA with a variety of known functions, including transcriptional activation and inhibition. Recent evidence has suggested that microRNA expression may influence the responsiveness of some cancers to chemotherapy, including liver and lung cancers. Some evidence has now suggested that specific microRNAs, such as miR-21, miR-155, and miR-375, may influence oral cancer responsiveness to chemotherapy – although much remains to be discovered.

Objective: Based upon the lack of evidence in this area, the primary objective of this study was to evaluate microRNA expression and responsiveness among oral cancers.

Methods: Five commercially available oral cancer cell …

Mapping Nevada's Dental Workforce, Kelvin Chen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Access to care is a concern at the forefront of public health. Due to socioeconomic and geopolitical pressures, the distribution of healthcare providers across a population often does not coincide with the demand for healthcare in a specific geographic area. Rural areas typically do not have enough providers and urban areas typically have too many. This stark reality underscores an inherent inefficiency in the allocation of healthcare resources and is a discrepancy that must be addressed by state-sponsored institutions and programs. From a public health perspective, the problem of insufficient or lack of access to care is the greater of …

Understanding The Role Of Ano1 In Oral Cancer, Mallary Forrest

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 2008, the gene ANO1 was discovered to encode a calcium activated chloride channel. This gene is located on the 11q13 locus, a locus that is commonly amplified in many cancers including cancer of the head and neck. ANO1 is situated in close proximity to genes associated with growth and apoptosis. As rapid proliferation and lack of apoptosis are hallmark characteristics of cancer, growth factors and apoptosis mediators are expected to be altered in cancer. But what does a calcium activated chloride channel have to contribute to cancer’s pathogenesis? Is it an active gene in cancer progression or is it …

Scardovia Wiggsiae And Streptococcus Sobrinus Prevalence Among Orthodontic And Non-Orthodontic Patients, Melissa Trumbo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: Dental cavities or caries have been identified as among the most prevalent of preventable oral conditions. However, studies are discovering new information regarding the incidence and prevalence of several cariogenic organisms, including Streptococcus mutans (SM), the recently discovered Scardovia wiggsiae (SW), as well as Streptococcus sobrinus (SS). These studies have revealed varying prevalence among different populations, such as those undergoing orthodontic treatment. Based upon this information, the main goal of the current study was to assess the prevalence of specific cariogenic organisms (SS and SW) within saliva samples originally obtained from a dental school-based clinic.

Methods: The protocol for …

Assessment Of The Infrazygomatic Crest And Distal Infrazygomatic Crest For Bone Depth And Miniscrew Insertion, Kyle C. Tuttle

UNLV Theses, Dissertations, Professional Papers, and Capstones

The aim of this study was to analyze and compare the bone depth at various postulated miniscrew insertion angles in both the Infrazygomatic Crest (IZC) and Distal Infrazygomatic Crest (DIZC) regions. Furthermore, root morphologies of the maxillary 1st and 2nd molars and their effect on bone depth and the various miniscrew insertion angles were analyzed.

A total of 69 CBCT images were collected from pre-orthodontic adult patients at the UNLV orthodontic residency clinic. Bone depth measurements were made at 8 postulated miniscrew insertion angles starting at 40° up to 75°. All measurements were recorded from the buccal bone at the …

Analysis Of Palatal And Upper Airway Dimensions In Patients With Excessive Daytime Sleepiness: A Retrospective Cone-Beam Computed Tomography Study, Daniel Jarrett

UNLV Theses, Dissertations, Professional Papers, and Capstones

Excessive Daytime Sleepiness (EDS) is the measure of ones propensity to fall asleep during normal daily activities. It has been reported in 20%-50% of adults in the United States and is the most frequent symptom of patients presenting to sleep clinics. EDS is the result of both primary hypersomnias such as narcolepsy and idiopathic hypersomnia and, more commonly, secondary hypersomnias such as sleep deprivation, psychiatric conditions, medications, illegal substances, and obstructive sleep apnea (OSA).

The etiology of OSA is multifactorial. Collapsibility of the upper airway is influenced by both neuromuscular tone and craniofacial anatomy. Common predisposing factors for small airways …

A Comparison Of Lateral Cephalometric And Arch Dimension Changes In Patients With Class Ii Malocclusions Treated With 2-Premolar And 4-Premolar Extraction Patterns, Melissa Marie Ven Dange

UNLV Theses, Dissertations, Professional Papers, and Capstones

The aim of this study is to gather and analyze data representing detailed changes in model and cephalometric variables that will support clinicians in the premolar extraction decision- making process during camouflage treatment of class II dental patients. It is expected that the models, as measured by intra-arch dimensions, overjet, overbite, and mandibular crowding, and cephalometric radiographs, evaluated by their anteroposterior skeletal discrepancy, incisor inclinations, dental and skeletal vertical positions, and soft tissue characteristics, will significantly differ from within the same treatment group, pre-treatment to post-treatment, and between treatment groups. This retrospective study evaluated the model and cephalometric changes in …

A Comparison Of Orthodontic Intraoral Scan Results Between Staff And Volunteers, Andrew Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Objective: This pilot study is the first to assess and compare a trained staff’s intraoral scan to a clinical examination by comparing the overbite, overjet, Angle canine and molar classification, and gingival health. The second part of this study is to determine if the self-scan scan from a patient is as reliable to the staff’s scan. Introduction: Orthodontic treatment is usually provided over a sequence of appointments. During each appointment, the doctor clinically evaluates the patient, analyzes the progress and provides adjustments to continue with the treatment. The most common clinical criteria evaluated are overbite, overjet, upper and lower midlines, …

3d Upper Airway Analysis Of Skeletal Class I, Ii, And Iii Adults With High Or Low Risk For Excessive Daytime Sleepiness, Alexander Dao

UNLV Theses, Dissertations, Professional Papers, and Capstones

Objective: To investigate the differences in ethnicity, BMI, sex, total airway volume, minimum cross-sectional area, airway shape, and hyoid bone position in high risk for excessive daytime sleepiness vs low risk for excessive daytime sleepiness in skeletal class I, II, and III patients

Introduction: Obstructive Sleep Apnea (OSA) is an underdiagnosed medical condition with many negative consequences on a patient’s overall health (Dempsey, J.A., Veasey, S.C., Morgan, B.J., & O’Donnell, 2010). OSA is defined as the occurrence of at least 5 instances per hour of sleep during which breathing temporarily stops (Motamedi, McClary, & Amedee, 2009). Undiagnosed OSA could lead …

Comparison Of Digital Treatment Setups And Final Treatment Outcomes Of Class Ii Division 1 Malocclusions Treated With Premolar Extractions, Sogol Shantiyai

UNLV Theses, Dissertations, Professional Papers, and Capstones

Objective: This study aimed to determine whether there are differences between pre-orthodontic treatment dimensions when compared to the virtual treatment simulations and actual orthodontic treatment outcomes in Class II malocclusions treated with two or four premolar extractions.

Introduction: The use of intraoral scanners has become commonplace in orthodontic practices, giving practitioners the ability to scan and assess maxillary and mandibular dental morphology and occlusal relationships chairside and in real-time. Practitioners can use virtual treatment planning to evaluate different extraction patterns, visualize potential non-extraction outcomes using interproximal reduction, and alter anchorage strategies based on the amount of retraction or protraction required …

Prevalence Of Aggregatibacter Actinomycetemcomitans And Fusobacterium Nucleatum Among Clinical Orthodontic Saliva Samples, Jason Robert Klingler

UNLV Theses, Dissertations, Professional Papers, and Capstones

Changes to the oral microflora occur when there are shifts in the levels of the numerous bacterial species. Changes in bacterial load occur in health, disease, and dental treatments such as orthodontics and can be detected through saliva. Many studies dealing with saliva have centered around detecting bacteria known for correlation with chronic periodontitis and caries. Fewer have focused on bacterial species that contribute to microbial shifts not strictly correlated with disease. Measuring the degree of disease progression or future susceptibility is not always possible with traditional clinical parameters alone.

Aggregatibacter actinomycetemcomitans (AA) is a bacterial strain that serves as …

Dental Age Estimation Of A Southern Nevada Hispanic Non-Adult Population Employing The London Atlas To Evaluate Archival Orthodontic Cone Beam Computed Tomography (Cbct) Images, Haley Buchanan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Age estimation is of societal importance for legal, forensic, and clinical reasons. The London Atlas of Human Tooth Development and Eruption, hereafter referred to as the London Atlas, was introduced as an improved method for determining dental age estimation. The London Atlas was developed from panoramic images of 528 living British Caucasian and Bangladeshi males and females aged 2 to 24 years and panoramic images of 176 archival human skeletal remains, aged 32 in utero to 2 years old, from two specimen collections (AlQahtani, Hector, & Liversidge, 2010). Further investigation is warranted to determine validity of the atlas’s use in …

Effect Of Bmp Treatment On Periostin Gene Expression In Pre-Osteoblastic Mc3t3-E1 Mouse Cells, Vincent Lee Khang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Periostin is a secreted, extracellular matrix (ECM) protein widely expressed within collagen-rich fibrous connective tissues of the body including the periodontal ligament (PDL), bone, skin, heart, and cornea. Periostin has been shown to serve many important regulatory functions including cell adhesion, cell motility, wound healing and of particular importance to the dental field, differentiation of osteoblasts. The deletion of periostin compromises osteoblast attachment to bone matrix and induces a reduction in mineralization and expression of bone markers, including type I collagen, osteocalcin, osteopontin and alkaline phosphatase. Periostin has also been shown to play a significant role in collagen fibrillogenesis by …

Prevalence Of Cariogenic Microbial Flora Among Scardovia Wiggsiae-Positive And Negative Patients, Amy Tam

UNLV Theses, Dissertations, Professional Papers, and Capstones

The formation of dental caries (cavities) is a complex, multi-dimensional process that necessarily involves many risk factors – including the acquisition and colonization of cariogenic oral bacteria. The most frequently associated oral pathogens are the acid-producing and acid-tolerant oral streptococcus species, such as Streptococcus mutans (S. mutans or SM). Many studies have established and confirmed the critical role of the formation of biofilm in the virulence of S. mutans, and the critical role this may play in determining the balance of the oral microbiome towards health or disease.

More recent efforts have discovered a novel cariogenic pathogen, Scardovia wiggsiae (S. …

Interleukin-1 Beta (Il-1Β) Gene Polymorphisms In Pre-Treatment Orthodontic Patients Exhibiting Short Root Anomaly (Sra), Satyaprasad Nayak

UNLV Theses, Dissertations, Professional Papers, and Capstones

Root resorption is a frequent unwanted occurrence during orthodontic treatment. Biological factors include the quantity of specific inflammatory mediators, growth factors, and hormones as well as an individual’s specific alleles for the genes encoding these mediators. Studies have shown an association between external apical root resorption (EARR) and the single nucleotide polymorphism (SNP) at +3954 of the IL-1β gene. Studies have also shown associations between chronic periodontitis and IL-1β gene polymorphisms in the region of +3954, -511 and -31. All previous studies to date, have evaluated genetic factors and root resorption in orthodontic patients in-treatment or post-orthodontic treatment. This study …

3-D Upper Airway Comparison Between Class I And Class Ii Adults With Excessive Daytime Sleepiness, Nga Nguyen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Objective: The aim of the study is to determine whether there is a relationship between the risk for daytime sleepiness in adults with Class I and Class II malocclusion and the airway volume, minimum cross-sectional area, and shape at the minimum cross sectional area.

Introduction: Sleep disordered breathing (SDB) is a category of conditions defined by airway complications while a person is sleeping. Obstructive sleep apnea (OSA) is the most common of these disorders and is defined as the presence of repeated episodes of complete or partial airway obstruction, which may be associated with loud snoring and daytime sleepiness. Daytime …

Levels Of Interleukin-1Β And Interleukin-17 In The Tension And Compression Sites Of Teeth During Orthodontic Movement, Suzanne Wen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Orthodontic tooth movement requires coordinated bone resorption and deposition in response to mechanical stimuli. Underlying this process is a complex network of biological signaling to activate osteoclasts and osteoblasts. The broad category of small proteins known as cytokines include many potential mediators involved in complex interactions to initiate tooth movement. One of the signaling factors is interleukin-1β (IL-1β), which plays a critical role in inflammation and bone erosion via the activation of osteoclasts. IL-1β is a key cytokine involved in osteoclast differentiation, multinucleation, and overall survival. Recently, interleukin-17 (IL-17) has been identified as a potent inducer of inflammation that influences …

Screening For The Novel Cariogenic Pathogen Scardovia Wiggsiae Among Orthodontic Patients, Adam Whiteley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Screening for the Novel Cariogenic Pathogen Scardovia wiggsiae among Orthodontic Patients

by

Adam Whiteley

Dr. Karl Kingsley, Examination Committee Chair Professor of Biomedical Sciences University of Nevada, Las Vegas School of Dental Medicine

The recent discovery of a novel cariogenic pathogen Scardovia wiggsiae has led many scientists and oral health researchers to re-evaluate and re-examine existing saliva repositories to determine the prevalence among patient populations. Recent efforts at this institution have used existing saliva samples to determine the prevalence among both adults and pediatric patients. These studies have revealed this organism may be found in approximately one-quarter of all samples …

The Effects Of Orthodontic Appliance Base Plate Material, Pmma, Infused With Silver And A Novel Antibacterial Compound On Biofilm Formation, Ryan D. Jolley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Retention is required in the majority of orthodontic patients throughout the remainder of their life. The traditional Hawley style retainer is still considered by many orthodontic professionals to be the gold standard in retention appliances. The orthodontic population, in general, is at a higher risk for caries due to plaque accumulation from poor diet, suboptimal oral hygiene, and often a lack of motivation. A Hawley retainer that reduces caries-causing oral microbes could improve oral health and be very beneficial to the post-orthodontic patient. Developing methods to safely include antibacterial products within the Hawley retainer’s base plate material could help effect …

Differential Cbct Analysis Of Collum Angles In Maxillary And Mandibular Anterior Teeth In Patients With Different Malocclusions, Erin Shane Wan Ma

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: The collum angle is an angular measurement of the difference between the longitudinal axis of the crown and the longitudinal axis of the root. The aim of this study was to determine the mean collum angles for all maxillary and mandibular anterior teeth. In addition, the collum angles of different molar and skeletal classifications were compared for each anterior tooth.

Methods: Based on patient records obtained from the University of Nevada, Las Vegas Department of Orthodontics and Dentofacial Orthopedics, 326 CBCT scans were selected and divided into four molar and skeletal classifications. The patients were divided into Class I, …

The Effects Of Cryopreservation On Human Dental Pulp-Derived Mesenchymal Stem Cells, Allison Elaine Tomlin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Many studies have demonstrated clinical applications for the use of dental pulp stem cells (DPSC) for the treatment of various conditions. This has driven medical and scientific interest in the collection, isolation and banking of DPSC tissues for research into these potential therapies. Few studies to date have evaluated the viability of DPSC following long-term cryopreservation. The purpose of this study is to evaluate the effects of cryopreservation on dental pulp-derived stem cells (DPSC) viability over a period of three years. Dental pulp-derived stem cells were isolated and cultured from thirty-one healthy teeth. DPSC isolates were assessed for doubling-time and …

Oral Microbial Burden Of Periodontal Pathogens Among Orthodontic Patients, David Jolley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Objectives

Many research studies involving orthodontic patients have a natural inclination to focus on changes in levels of cariogenic pathogens after bracket placement, and very few studies examine the role of changes of periodontal pathogens – particularly among adult patients. Interestingly, recent evidence suggests that increased levels of a specific periodontal pathogen, Fusobacterium nucleatum, may elevate risk for development of colon cancer in adults through direct pathways. Based upon this new evidence, the objective of the current study was to screen saliva samples taken from orthodontic patients to determine the prevalence of periodontal pathogens, including F. Nucleatum, T. denticola, and …

The Effect Of Attachment Placement And Location On Rotational Control Of Conical Teeth Using Clear Aligner Therapy, Pouya Momtaz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Objective: To determine the optimal method to correct rotations of conical teeth using

thermoplastic appliances with and without attachments.

Introduction: Despite the increasing popularity of clear aligner therapy there are still questions as to its effectiveness, efficiency, case selection and limitations. It has been reported that the full prescription for clear aligners is not expressed, and that the mean accuracy of any type of tooth movement using clear aligners is only 41% (Drake, 2012). One of the major limitations of clear aligner therapy is correction of rotated conical teeth, especially canines and premolars (Kravitz, 2008). According to Simon, et al. …

Cbct Evaluation Of Adolescent Mandibular Morphology In Different Classifications Of Facial Type, Annie Hsu

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this study is to use the improved imaging capability of cone-beam computerized tomography (CBCT) to investigate the relationship between vertical facial patterns and mandibular tooth-alveolar morphology in the adolescent population. Pre-treatment orthodontic records were obtained from the UNLV School of Dental Medicine archival dental records. One hundred and seventy three patients (72 males, 101 females) between the ages of 12 and 18 years were included in this study. Among these patients, 61 displayed the vertical growth pattern, 30 displayed the horizontal growth pattern, and 82 displayed the average growth pattern. The samples were categorized into 4 age …

Scardovia Wiggsiae Prevalence In Orthodontic Patients, Brandon Joseph Streiff

UNLV Theses, Dissertations, Professional Papers, and Capstones

Dental caries has mainly been associated with Streptococcus, Lactobacillus, Actinomyces and Veillonella species. But in recent salivary studies a new cariogenic pathogen, has been identified. This new bacteria, Scardovia wiggsiae (SW), is currently being tested within the UNLV School of Dental Medicine patient population. Although these current studies are being conducted to study its prevalence in both pediatric and adult populations, it has not been evaluated among patients with an altered oral environment as seen in patients with orthodontic appliances. Fixed orthodontic appliances increase the difficulty of removing daily plaque on and in between the teeth with standard oral hygiene …