Dentistry Commons^™

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. …

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 …

Randomized Controlled Clinical Trial On Bleaching Sensitivity And Whitening Efficacy Of Hydrogen Peroxide Versus Combinations Of Hydrogen Peroxide And Ozone, Mahmoud K. Al-Omiri, Abdullah A. Al Nazeh, Andrej M. Kielbassa, Edward Lynch

Dental Medicine Faculty Research

The clinical efficacy regarding bleaching sensitivity and tooth shade lightening using a standard hydrogen peroxide (H2O2) bleaching gel was compared with the additional use of ozone either before or after application of H2O2. Using computer-generated tables, 45 participants were randomly allocated into three groups (n = 15 each) in this investigator-driven, single-centre trial. In Group 1, upper anterior teeth were bleached using ozone (produced via a healOzone X4 device) for 60 seconds, then 38% H2O2 for 20 minutes; in Group 2, 38% H2O2 application (20 min) was followed by ozone (60 s); air produced by the healOzone machine (60 s) …

Accuracy Of Full-Arch Scans Using Intraoral And Extraoral Scanners: An In Vitro Study Using A New Method Of Evaluation, Jonas Muallah, Christian Wesemann, Roxana Nowak, Jan Robben, James Mah, Peter Pospiech, Axel Bumann

Dental Medicine Faculty Research

The aim of this study was to compare the accuracy of six intraoral scanners as regards clinically relevant distances using a new method of evaluation. An additional objective was to compare intraoral scanners with the indirect digitization of model scanners. A resin master model was created by 3D printing and drilled in five places to reflect the following distances: intermolar width (IMW), intercanine width (ICW), and arch length (AL). To determine a gold standard, the distances were measured with a coordinate measuring instrument (Zeiss O-Inspect 422). The master model was scanned 37 times with the following intraoral scanners: Apollo DI …

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 …

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 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 …

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, …

Ozone Treatment Of Recurrent Aphthous Stomatitis: A Double Blinded Study, Mahmoud K. Al-Omiri, Mohannad Alhijawi, Bader K. Alzarea, Raed S. Abul Hassan, Edward Lynch

Dental Medicine Faculty Research

This study aimed to evaluate the use of ozone to treat recurrent aphthous stomatitis (RAS). Consecutive sixty-nine participants with RAS were recruited into this non-randomized double blind, controlled cohort observational study (test group). A control group of 69 RAS patients who matched test group with age and gender was recruited. RAS lesions in test group were exposed to ozone in air for 60 seconds while controls received only air. Ulcer size and pain were recorded for each participant at baseline and daily for 15 days. Ulcer duration was determined by recording the time taken for ulcers to disappear. The main …

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 …

Assessment Of Orthodontic Patients' Preferences Regarding Treatment From General Dentists Or Orthodontists, Brian Robert Wilde

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study evaluated how parents of prospective orthodontic patients choose between taking their child to a general dentist or an orthodontist for orthodontic treatment. It also looked at which factors influence patients’ satisfaction with the progress of treatment and likelihood to refer other patients to the practice. This study included two phases. The first phase was a qualitative assessment of the decision making process through conducting and analyzing focus groups. The second phase was the development and administration of a nationwide online survey regarding the topics covered in the focus groups. Influential factors in the decision making process fell into …

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 …

Experiences With The Streptococcus Mutans In Lakota Sioux (Smiles) Study: Risk Factors For Caries In American Indian Children 0-3 Years, David R. Drake, Deborah Dawson, Katherine Kramer, Amy Schumacher, John Warren, Teresa Marshall, Delores Starr, Kathy Phipps

Journal of Health Disparities Research and Practice

Severe Early Childhood Caries (S-ECC) is a terribly aggressive and devastating disease that is all too common in lower socio-economic children, but none more so that what is encountered in American Indian Tribes. Nationwide, approximately 27% of 2-5 year olds have decay while 62% percent of American Indian/Alaska Native children in the same age group have a history of decay (IHS 2010, NHANES 1999-2002). We have conducted a study of children from birth to 36 months of age on Pine Reservation to gain a better understanding of the variables that come into play in the development of this disease, from …

Designing A Mechanical Linkage Capable Of Decreasing Force Transfer From The Facemask To The Protective Helmet When Loading Occurs, Levi Hansen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction

Sports that involve extensive personal contact have a high incidence of injury. The introduction of regulations mandating the use of personal protective equipment in these sports is the most common injury control strategy (Marshall et al., 2002). Negligible attention has been paid to the mechanical linkage between the facemask and helmet as a means of reducing force transfer from the facemask, through the helmet, and to the head and or neck of the athlete.

Methods

A novel prototype mechanical linkage of reasonable simplicity that provides 360° of freedom in motion capable of decreasing force transfer from the facemask to …

Induction Of Differentiation Of Dental Pulp-Derived Mesenchymal Stem Cells (Dpsc), Aubrey Young

UNLV Theses, Dissertations, Professional Papers, and Capstones

Mesenchymal stem cells are derived from a variety of human tissues and are being bioengineered and studied for possible uses in the advancement of medicine. Recent efforts are being focused on Dental Pulp Stem Cells (DPSC's) due to the accessibility of this tissue. Many factors influence DPSC quality and quantity, including the specific methods used to isolate, collect, concentrate, and store these isolates once they are removed. Ancillary factors, such as the choice of media, the selection of early versus late passage cells, and cryopreservation techniques may also influence the differentiation potential and proliferative capacity of DPSC isolates.

The objective …

Designing A Process To Reliably Split Extracted Teeth To Access The Dental Root Canal, Happy Singh Ghag

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction

Mesenchymal stem cell (MSC) research is a contemporary topic in modern healthcare. These cells have the ability to divide and generate progeny, which then become committed to specific and distinctive end-stage phenotypes, such as cartilage or bone (Caplan 1991). MSCs have been isolated from a variety of tissues such as the umbilical cord, bone marrow, adipose tissue (Ding, Shyu & Lin 2011) and dental pulp (Takeda et al 2008). Although dental pulp is a viable source for MSCs, peer reviewed research has given limited attention to its retrieval process through intentional tooth splitting of extracted teeth. The purpose of …

Retention Of Low Income Children In Three Dental Studies Investigating Early Childhood Caries, Ann H. Saba, John J. Warren, Karin Weber-Gasparoni, Deborah V. Dawson

Journal of Health Disparities Research and Practice

Background: To our knowledge no dental studies have looked closely at subject retention, which is crucial to better understand oral health disparities. In this paper, we report retention rates and review and attempt to assess which retention strategies utilized in 3 dental research studies investigating ECC were effective for retaining WIC-enrolled children. The purpose of this paper is to discuss challenges that were encountered when working with these populations, describe characteristics of those not retained, and summarize some recommendations for future dental studies working at WIC sites. Methods: Three dental studies were conducted at WIC clinics in Iowa. Retention strategies …

Determinants Of Head And Neck Cancer Survival In Nevada For 1995-2008, Xiao Q. Li

UNLV Theses, Dissertations, Professional Papers, and Capstones

Head and neck cancer (HNC), also known as oral cavity and pharyngeal cancer, comprises a group of cancers that arise in the head or neck region, such as the nasal cavity, sinuses, lips, mouth, salivary glands, and pharynx. Use of tobacco, alcohol, or a combination of the two, are major risk factors for head and neck cancer. Approximately 75% of oral cancers are attributable to smoking and/or alcohol consumption. More recently, the human papilloma virus (HPV) has also been associated with the development of head and neck cancer.

The objective of the present study is to investigate head and neck …

3-D Oropharyngeal Airway Analysis Of Different Antero-Posterior And Vertical Craniofacial Skeletal Patterns In Children And Adolescents, Chi Kim Huynh

UNLV Theses, Dissertations, Professional Papers, and Capstones

Sleep apnea disorder has recently emerged as a significant public health issue. While the prevalence of obesity is on the rise among children, it is one of the main risk factors associated with apnea. Upper airway dimensions and morphology seem to be major components of obstructive sleep apnea (OSA) and can be affected by different craniofacial patterns. The purpose of this retrospective, cross-sectional pilot study is to correlate gender, Body Mass Index, risk for OSA, neck circumference, and 3-D oropharyngeal airway dimensions in children and adolescents with different antero-posterior (AP) and vertical craniofacial skeletal patterns. A total of 86 pre-orthodontic …

New Mouthguard Design With Intermediate Nickel-Titanium And Foam Layer, Freddie Martinez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Mouthguards help prevent orofacial injuries in many physical activities, commonly to the maxillary incisors. Mouthguards have many different properties which can be idealized. One property involves the amount of impact force the mouthguard can dissipate, commonly referred to as shock absorption. The aim of this study was to improve shock absorption capabilities beyond the protection that a mouthguard made of Ethylene Vinyl Acetate (EVA) can offer. A Nickel-Titanium (NiTi) and/or foam intermediate layer was placed between EVA. Seven configurations were fabricated at 3 different thicknesses. The configurations consisted of an intermediate layer composed of NiTi, foam, or NiTi/foam. The NiTi …

Sex Determination Using Discriminant Function Analysis In Hispanic Children And Adolescents: A Lateral Cephalometric Study, Alyssa E. Sprowl

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lateral cephalometric radiographs have been used for years to help diagnose skeletal and dental patterns in Orthodontics. Within the last decade, these radiographs have caught the interest of the department of Anthropology for the identification of gender within the adult and adolescent population. Numerous publications have been made but failed to identify sexual dimorphism in the pre-adolescent population. 303 lateral cephalograms of pre and post Latino adolescence age ranging from 6.5 to 17.9 years old were obtained from University of Nevada, Las Vegas (UNLV) digital database. 25 variables were identified and plotted with all linear and angular measurements transferred into …

Adult Permanent (Extracted) Teeth As A Source Of Dental Pulp-Derived Mesenchymal Stem Cells (Dpsc): A Pilot Study, Charles Hill

UNLV Theses, Dissertations, Professional Papers, and Capstones

Mesenchymal stem cells (MSC) may be derived from a variety of adult human tissues, including dental pulp from extracted or exfoliated teeth. Evidence suggests differences in both the quality and quantity of the dental pulp-derived mesenchymal stem cells (DPSC) obtained from different sources, such as primary or "baby teeth" and adult, permanent teeth. This study aimed to evaluate the potential to obtain DPSC from intact, vital permanent teeth, and characterize the potential isolates using a randomized selection of active dental patients from the University of Nevada, Las Vegas School of Dental Medicine (UNLVSODM). DPSC were extracted, isolated, cultured and characterized …

Design And Testing Of Novel Mouthguard With Intermediate Nitinol And Foam Layers, Adam Kessler

UNLV Theses, Dissertations, Professional Papers, and Capstones

It is the aim of this study to investigate a novel mouthguard design that incorporates the use of a nickel-titanium (Nitinol) layer and thin foam layer in addition to EVA layers. It is thought that the Nitinol layer can distribute the force of an impact and that the thin foam layer may absorb this distributed force better than a solid EVA mouthguard of the same thickness. Rectangular, flat coupons representative of several mouthguard configurations were constructed for testing using an instrumented drop-weight impact tower. The coupon configurations include a control made of laminated EVA, a group of laminated EVA and …

Awareness And Beliefs Regarding Intimate Partner Violence Among First-Year Dental Students, Rhonda J. Everett, Karl Kingsley, Christina A. Demopoulos, Edward E. Herschaft, Christine Lamun, Sheniz Moonie, Timothy J. Bungum, Michelle Chino

Environmental & Global Health Faculty Research

Intimate partner violence (IPV) may affect one to four million individuals per year in the United States, with women accounting for the majority of both reported and unreported cases. Dental professionals are in a unique position to identify many types of IPV because injuries to the head and neck may be indicators or predictors of IPV abuse. Fewer than half of dental programs surveyed have reported having IPV-specific curricula, and most dental students surveyed have reported having little experience or training to recognize IPV. Based on this information, this pilot study sought to assess the awareness and beliefs regarding IPV …

An Analysis Of Adhesion Promoters On Shear Bond Strength Of Orthodontic Brackets To Teeth, Loren Andrew Cadelinia

UNLV Theses, Dissertations, Professional Papers, and Capstones

Purpose:The aim of this study was to evaluate the shear bond strength of two adhesion promoters, EnhancetmLC and AssureRUniversal Bonding Resin, and their effects with two different adhesion systems (Light Bondtmand TransbondtmXT). To better understand their behavior upon failure, the amount of adhesive remnant remaining on the tooth surface was also observed.

Methods:One-hundred forty human premolars, which were extracted for reasons other than this study, were utilized and divided into seven groups of 20 teeth each. Groups A1 and B1 were bonded without adhesion promoters and with two different adhesive systems - Light Bondtmand TransbondtmXT. Groups A2 and B2 were …

Frictional Forces Of A Fixed, Esthetic Orthodontic Appliance System, Brady Michael Nance

UNLV Theses, Dissertations, Professional Papers, and Capstones

Purpose: The demands of an all esthetic fixed orthodontic appliance system are ever increasing in today's world. Frictional values of an esthetic, fixed orthodontic appliance system are needed to evaluate their clinical effectiveness for orthodontic treatment. The aim of this study is to evaluate the frictional values of various esthetic orthodontic archwires ligated to an esthetic orthodontic bracket.

Methods: Three types of stainless steel and nickel titanium alloy (niti) esthetic orthodontic archwires (epoxy, poly, plastic) in four sizes (.016, .018, .017 x .025, .019 x .025 inches) were ligated to both a stainless steel bracket system and a ceramic (esthetic) …

Oral Health Needs And Parental Attitudes, Behavior, And Knowledge Of Lower Ses Children, Mildred Mcclain, Clifford R. Mcclain, Anthony Paventy

Nevada Journal of Public Health

Despite the declining prevalence of dental caries over recent decades, caries remain the most common chronic childhood disease, especially in high-risk (low socio-economic status) populations. This appears to be true even when parents are aware of good oral health habits. The purpose of this study was to gather oral hygiene data on high-risk children in Nevada and to assess parental attitudes and education concerning their children’s oral health. Using visual examinations and a dmft (decayed, missing, filled, teeth) severity index, 235 lower SES children were screened and given treatment recommendations. The screenings showed larger than expected prevalence in both caries …

Analysis Of Lead Levels In Deciduous Teeth From Children In Clark County, Nevada., Kristin Murphy, Jennifer Berger-Ritchie, Shawn L. Gerstenberger, Amol B. Amin, Jason K. Nitta, Frederick G. More, Jeanne A. Hibler, Karl Kingsley

Nevada Journal of Public Health

Background: Elevated blood lead levels (EBLL) are declining in the United States, although some population subgroups continue to exhibit significant health disparities. A childhood lead poisoning prevention program was recently started in Nevada, and many efforts have been made to support this program and increase the screening rates.

Methods: To expand the potential pool of children screened for EBLLs, a pilot study was performed to evaluate lead concentrations in extracted deciduous teeth using Graphic Furnace Atomic Absorption Spectrometry (GFAAS), Inductively Coupled Plasma Mass Spectrometry (ICP-MS), and X-Ray Fluorescence (XRF) analysis.

Results: Lead concentrations as determined by GFAAS and ICP-MS were …

Nutrition Education In Clark County, Nevada, Matt Bittle, Mildred Mcclain, Jeanne A. Hibler, Marcia M. Ditmyer

Nevada Journal of Public Health

Over 51 million school hours are missed annually by school-aged children due to a dental problem or visit, with 117 hours missed per 100 children (NIDCR, 2002). Approximately half a million of California's 7.2 million school-age children missed at least one day of school in 2007 because of dental issues such as toothaches (Pourat, & Nicholson, 2009). Independent research regarding various educational and intervention programs have been conducted in elementary schools across the country that focus on nutrition and/or physical activity, some of which have found that the programs positively impacted students’ dietary behaviors (Edwards, Mauch, & Winkelman, 2011; Muth, …