Dentistry Commons^™

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 …

The Role Of Porphyromonas Gingivalis In The Regulation Of Epithelial-Mesenchymal Transition Markers In Migration., Akintunde Ojo 1981-

Electronic Theses and Dissertations

A relationship between periodontal disease and oral squamous cell carcinoma (OSCC) has been demonstrated in recent studies. Porphyromonas gingivalis’ antigen have been found in oral cancer cells. The embryonic program “epithelial-mesenchymal transition” (EMT) is thought to trigger cancer invasion by allowing tumor cell propagation. The objective of this study was to examine the role of P. gingivalis in the expression of ZEB1, vimentin, and repression of miRNA-200 family as EMT prognostic markers in cancer cell metastasis. Human telomerase immortalized gingival keratinocytes (TIGK) cells were challenged with P. gingivalis strain ATCC 33277 in vitro for 24h at MOI 50 and 100. …

The Effect Of Root Canal Cleansing On The Retention Of Glass Fiber-Reinforced Posts, Faisal Dhaifallah Al-Qarni

Loma Linda University Electronic Theses, Dissertations & Projects

Esthetic glass fiber-reinforced posts are being used more often. The most commonly reported complication associated with these posts is debonding. Dentine conditioning with solutions such as EDTA or MTAD results in removal of smear layer and might improve the retention of posts to root canal dentin. Therefore, the purpose of this study was to investigate the effect of cleansing the post space with MTAD or EDTA on the bond strength of glass fiber-reinforced posts, when cemented with self-adhesive resin cement. Forty-five (n=15) extracted human premolar teeth were sectioned at the cemento-enamel junction to obtain root length of fifteen millimeters. Endodontic …

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 …

Disaster Preparedness & Response: A Survey Of U.S. Dental Hygienists, Brenda Tallon Bradshaw

Dental Hygiene Theses & Dissertations

Purpose: The purpose of this study was to determine dental hygienists' interests, formal education, views, comfort levels, and intentions for becoming involved in disaster preparedness and response as measured by a 21-item survey entitled "Victim Identification for Disaster Preparedness & Response: A Survey of Dental Hygienists". Methods: A nonprobability convenience sample (n=400) was recruited for an online survey. Data was analyzed for statistical significance using descriptive statistics, chisquare goodness-of-fit tests, a Mann-Whitney U test, and a paired-samples t-test. Similar themes were identified and categorized from open-ended questions. Results: A response rate of 83.5% (n=334) was attained. Regardless of years …

Knowledge, Attitudes, And Barriers Toward Evidence-Based Practice Among Oral Health Professionals In Saudi Arabia, Sukainah Abdulwahab Almeedani

Dental Hygiene Theses & Dissertations

Evidence -based decision making enables oral health professionals to make clinical practice decisions by utilizing the best available and most current scientific evidence. In combination with patients' values and circumstances, oral health professionals' experience and judgment are equally considered with scientific evidence in evidence-based decision making. The purpose of this study was to explore the knowledge and attitudes of evidence-based practice (EBP) among oral health professionals in Saudi Arabia and to determine the obstacles and barriers to implementation. Using a descriptive survey design, classrooms and clinics of 258 oral healthcare professionals were randomly selected from King Saud University, College of …

The Expression And Potential Significance Of Human Kallikreins 6, 7, 8, 10, 13, And 14 In The Epithelium Of Selected Odontogenic Cysts And Tumors Of Variably Aggressive Biological Behaviour, Rebecca Woodford

Electronic Thesis and Dissertation Repository

ABSTRACT

This study analyzed the immunohistochemical staining, localization and relative concentrations of human kallikreins (KLKs) 6,7,8,10,13,14 to determine if there is a predilection for odontogenic epithelium and if differential staining could predict biological behavior of selected odontogenic lesions.

We found that all KLKs studied were present in the epithelium of all lesions examined. However, there were significant differences in location of intra-epithelial staining and staining scores between the lesions. There was no significant, unexplainable difference in staining between odontogenic cysts and the control cyst indicating no specific role in odontogenic cystogenesis. However, the odontogenic neoplasms showed statistically significant increased expression …

Cbct Evaluation Of Morphological Changes To Alveolar Bone Due To Orthodontic Tooth Movement, Jeremy M. Hoff

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: The mandibular process is the anatomic factor that limits the orthodontic movement of the mandibular incisors, and awareness of this structural limitation may reduce the risk of potential damage to tooth roots and alveolar bone. A decision regarding the correct placement of the lower incisors will be largely determined by the amount of adaptation possible within the alveolar bone. Purpose: The purpose of this study was to use Cone Beam Computed Tomography (CBCT) to evaluate the adaptation of alveolar bone around the mandibular anterior teeth before and after orthodontic tooth movement. Methods: This study compared changes in area (mm2) …

Efficacy Of The Flosspro Flosser Versus Finger Flossing In Orthodontic Patients, Sharareh S. Sabet

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: The maintenance of good oral hygiene among orthodontic patients is a challenge. The purpose of this study was to compare the oral hygiene habits, gingival health, and preference of orthodontic patients when using a floss aid compared to conventional finger flossing with a floss threader. Methods: Thirty-four adolescent and young adult patients with fixed orthodontic appliances and poor oral hygiene were enrolled from the Loma Linda University Graduate Orthodontic Clinic. This was a single blind crossover study. The patients were randomly assigned to one of two treatment groups (floss aid or finger floss) in phase I. After prophylaxis, subjects …

Skeletal Changes After Rapid Maxillary Expansion And Fixed Orthodontic Treatment: A Cbct Study, Chandler Ho

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: The purpose of this study was to use cone-beam computed tomography to quantitatively evaluate the skeletal effects of rapid maxillary expansion and orthodontic treatment, with a specific interest in evaluating whether the skeletal changes achieved by RME will maintain throughout orthodontic treatment. Methods: Thirty consecutive patients (16 boys, 14 girls; mean age, 13.9 ± 1.8 years) who required RME with Hyrax appliances as part of their comprehensive orthodontic treatment were studied. Measurements before and after RME, and after orthodontic treatment, of palatal and buccal maxillary widths, palatal alveolar angle, nasal width, nasal floor width, and maxillary sinus width at …

Cbct And Cephalometric Analysis Of The Tmj Complex After Treatment Using A Mara Appliance, Melissa Danette Shotell

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: The mandibular anterior repositioning appliance (MARATM) is a fixed appliance intended for the correction of class II malocclusion. Many advocate the use of the MARA appliance to minimize patient non-compliance with treatment; however, little information is known as to the skeletal changes in the temporomandibular complex. The purpose of this study is to investigate the changes in the temporomandibular complex using both cephalometric and cone beam computerized tomography.

Materials and Methods: The initial and final treatment cone beam computerized tomography (CBCT) scans of 5 patients treated with the MARA appliance were collected from the Loma Linda University Orthodontics Clinic. …

Copper, Aluminum And Nickel: A New Monocrystalline Orthodontic Alloy, Mark Wierenga

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: This study was designed to evaluate, via tensile and bend testing, the mechanical properties of a newly-developed monocrystalline orthodontic archwire comprised of a blend of copper, aluminum, and nickel (CuAlNi). Methods: The sample was comprised of three shape memory alloys; CuAlNi, copper nickel titanium (CuNiTi), and nickel titanium (NiTi); from various orthodontic manufacturers in both 0.018” round and 0.019” x 0.025” rectangular dimensions. Additional data was gathered for similarly sized stainless steel and beta-titanium archwires as a point of reference for drawing conclusions about the relative properties of the archwires. Measurements of loading and unloading forces were recorded in …

The Effect Of Tooth Presence On Identification Of Tooth Socket Lamina Dura Surface: A Cbct Study, Morse Stonecypher

Loma Linda University Electronic Theses, Dissertations & Projects

Aim: The accuracy in identifying anatomical landmarks on CBCT images can be affected by the presence of surrounding anatomical structures with similar radiodensity. The purpose of this study was to evaluate the effect of the presence of tooth structure on the accuracy in identifying the lamina dura surface, facial bone surface, facial and lingual bone margins, socket apex, as well as in facial bone thickness measurement. Materials & Methods: Three fresh cadaver heads were scanned using a NewTom 5G CBCT at 0.100 mm voxel size at three time-points: before extraction (T1), after extraction and reinsertion (T2), and after tooth removal …

Interleukin-6 Production And Epithelial Cell Signaling By Telomerase Immortalized Gingival Keratinocytes In Porphyromonas Gingivalis Infection., Himabindu Vuddaraju

Electronic Theses and Dissertations

P. gingivalis is a major periodontal disease causing pathogen. Gingival epithelial cells being the first line of defense, interact and internalize the bacteria evoking a cell signaling response that finally leads to the release of cytokines. IL-6 is a potent pro- inflammatory cytokine, which is one of the responsible factors for bone resorption, a clinical manifestation of periodontitis. The experimental model study hypothesizes that P. gingivalis infection increases the production of IL-6 in telomerase immortalized gingival keratinocytes (TIGKs) through up-regulation of c-Jun (AP-1 reporter). We observed the IL-6 production post-infection with P. gingivalis WT ATCC33277 and mutants ?0482, ?Ndk and …

Cholinergic Inhibition Of Lipopolysaccharide Induced Matrix Metalloproteinase In Immune Cells., Harrison Black,

Electronic Theses and Dissertations

Background: Matrix metalloproteinase (MMPs) are proteins that have a unique role in immunity, tissue remodeling, and tumorigenesis. MMPs can break down extracellular components, release bioactive molecules, and act on pro-inflammatory cytokines, chemokines and other proteins to regulate varied aspects of inflammation and immunity. Nicotine (3-(1-methyl-2-pyrrolidinyl) pyridine), a key toxic component of tobacco, is thought to dysregulate matrix metalloproteinase secretion in immune cells. Aim: Examine the effect of nicotine on MMP9 secretion and activity in primary monocytes. Methods: Primary monocytes were stimulated with LPS (1 µg/ml) and Nicotine (100 ng/ml) and MMP9 secretion were studied. Gel zymography and ELISA techniques were …

Comparing The Vertical Misfit Of Casts Produced By Two Verification Jigs, Abdulaziz Saeed Alqahtani

Master's Theses (2009 -)

Purpose: To compare the dimensional accuracy between master casts fabricated with verification jigs made of acrylic resin and light cure Triad. Materials and Methods: 10 GC Pattern resin Pattern verifications jigs and 10 Triad gel verification jigs fabricated of a master cast of a mandibular model of 4 internal hex implants. A stone base was fabricated for each verification jig. One screw test was used to evaluate the vertical gap at the terminal abutment using a digital micrometer with an accuracy of 1μm to record the vertical gap for each sample. Results: Triad Gel group has the lowest average distortion …

Microstructure And Mechanical Properties Of Nickel-Free And Nickel-Containing Stainless Steel Orthodontic Wires, Amanda Olejniczak

Master's Theses (2009 -)

Introduction: In orthodontics, contact dermatitis caused by nickel allergy should be of concern with the number of nickel-containing appliances and wires used. Stainless steel archwires are commonly used throughout orthodontic treatment. With the release of nickel from these wires, some manufacturers have turned to nickel-free stainless steel alternatives. The goal of this research was to compare nickel-free stainless steel with traditional stainless steel archwires with regard to mechanical properties and microstructure. Materials and Methods: Nickel-free stainless steel and regular stainless steel archwires from four companies were included. Five random samples of each wire, vertically mounted in fast-set acrylic, were indented …

Composition, Phase Structure, And Corrosion Of Nickel-Free And Nickel-Containing Stainless Steel Orthodontic Wires, Amrita Rakalla

Master's Theses (2009 -)

Stainless steel wires have long been used in orthodontics. The austenitic stainless steel used in orthodontics contains approximately 18 wt% chromium and 8 wt% nickel. Nickel improves the corrosion resistance and helps maintain the austenite structure of stainless steel. Nickel is the most allergenic metal and is the most common metal associated with contact dermatitis in orthodontics. Nickel-free wires have been developed, and it was the goal of this study to compare nickel-free and nickel-containing stainless steel orthodontic wires to determine and compare their composition, phase structure, and corrosion properties. For each test, nickel-free and conventional stainless steel wires were …

Dimensional Changes Of Facial Soft Tissue Associated With Rapid Palatal Expansion, Peter Charles Longo

Master's Theses (2009 -)

Introduction: Orthodontic treatment demands excellent outcomes in both function and esthetics. Despite the popularity of rapid palatal expansion in orthodontic treatment, few studies have examined its consequences on facial soft tissue using direct anthropometric measurements. The primary goal of this study was to determine facial soft tissue changes immediately following rapid palatal expansion. Materials and Methods: Twenty-eight patients (age range, 8-17 years) attending Marquette Dental School Orthodontic Post-Graduate Clinic were enrolled in the study. Facial soft tissue measurements were taken with digital calipers at two separate time points (T0: initial exam and T1: thirty days following expansion); measurements were recorded …

Effect Of Mechanical Vibration On Resistance To Sliding In The Fixed Orthodontic Appliance, David Robert Kennedy

Master's Theses (2009 -)

Objective: To determine the effects of mechanical vibrations produced from electric tooth brushes and a commercially available device called AcceleDent, on the resistance to sliding at the bracket-arch wire interface. Materials and Methods: All as-received wires and brackets were cleaned with 95% ethanol prior to testing. An individual metal bracket was mounted on a custom metal fixture. The custom metal fixture had a polyurethane material that resembled the mechanical feature of the human periodontal ligament. The test metal bracket was aligned and bonded passively with 4 other non-movable brackets using a straight piece of .0215" X .025" SS wire. Another …

An Investigation Into The Bonding Properties Of New Generation Ceramic Brackets As Compared To A Stainless Steel Bracket, Ami Inoue

Master's Theses (2009 -)

Introduction: More patients are seeking esthetic alternatives for their orthodontic treatment options, which has led to increased use of ceramic brackets in recent years. These brackets were marketed before independent scientific research was completed. Many of the early ceramic brackets used a silane coupling agent to allow for a chemical bond between the bracket and the adhesive resin. Early reports from clinicians of increased bond strengths and iatrogenic tooth damage after bracket removal were common. Manufacturers have made changes to their base designs, relying more on mechanical retention for bond strength. The goal of this study was to test the …

Correlating Periodontal Disease And Cardiovascular Disease: A Comparative Study Of Research Methodology, Alexandra Hensen

Honors Theses

This meta-analysis compares and contrasts three types of population-based research methodology currently used to analyze correlations between Periodontal disease and Cardiovascular disease, the most wide spread diseases in the Western industrialized world. The three studies that were analyzed in this thesis include: "Gender Differences in the Relationship Between Periodontal Disease, Tooth Loss, and Atherosclerosis," published in the Journal of Stroke and Cerebrovascular Diseases (2013), this was a cross-sectional population-based study; "Periodontal Disease and Mortality in Type 2 Diabetes" published in Diabetes Care (2005), this was a longitudinal population-based study; and "Identification of a Shared Genetic Susceptibility Locus for Coronary Heart …

Novel Approach To Assess Periodontal Disease Severity Using Volumetric Analysis, Meera George Maveli

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to evaluate if the absolute change in linear measurements of bone loss on the facial plane of a maxillary central incisor at full and half root length along the vertical axis is directly proportional to volumetric change. The secondary aim was to evaluate if the variation of root volume is influenced by difference in root morphology.

Three dimensional digital models of 70 random patients were obtained from

DICOM CBCT files using volumetric software, InVivoDental (Anatomage, San Jose,

CA). One central incisor of average root length was selected per patient and total length

(L1) and …

Factors Affecting Gingival Recession In The Esthetic Zone: A Human Cadaver Study, Christen Sather

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to assess the correlation of gingival recession to the following parameters in fresh cadavers: gingival thickness, buccal bone loss, buccal bone thickness, shape of bony dehiscence defect, and age. A secondary aim was to evaluate predictors for gingival recession.

Sixteen fresh cadavers were used in this study. Gingival recession, facial gingival thickness, alveolar bone loss, and buccal bone thickness were measured at teeth #6-#11 and #22-#27. Sites with a dehiscence (D) or fenestration (F) were presented, and resultant bony defect shape was noted. The correlation of gingival recession to gingival thickness, buccal bone loss, …

Chemical Dental Plaque Control: Chlorhexidine Tooth Staining And Efficacy Of Common Whitening Procedures, Zoe Kiklis

Scripps Senior Theses

Chlorhexidine mouth rinses remove dental plaque from teeth, preventing dental caries, dental decay, and more serious systemic infections. Tooth discoloration due to extrinsic staining is the most prominent side effect of regular chlorhexidine use. Decreasing the concentration of chlorhexidine reduces staining area and severity. Staining can also be prevented and treated by tooth bleaching, a common cosmetic dental procedure that diminishes extrinsic staining by oxidizing chromagens adsorbed onto the tooth surface. In the proposed trial, common bleaching agents will be investigated for their efficacies in preventing chlorhexidine staining. Results of the trial could further the development of a chlorhexidine mouth …

The Reporting Of Supplement Use By Dental Patients On Their Medical History Questionnaire, Sarmad Bakuri

Theses and Dissertations

The Reporting of Supplement Use by Dental Patients on Their Medical History Questionnaire Objectives: The goals of the study were three fold. Estimate the prevalence of supplement use by dental patients. Determine if the design of a medical history form influences the prevalence of supplement use reported. Determine whether or not patients are aware of supplement side effects and interactions with medications. Methods: Patients were randomly allocated to either a standard medical history form or the same form with additional questions about supplement use. After completing the initial forms, a survey containing questions about supplements was filled out by both …

Mandibular Incisor Proclination Variability During Class Ii Correction, James Redford

Theses and Dissertations

Background: Lower incisor proclination has been shown to increase during Class II correction with appliances such as the Forsus. This lower incisor flaring shows great variability among patients. The purpose of this study was to evaluate the effects of Class II severity, mandibular growth, and occlusal plane rotation on lower incisor flaring in patients treated with the Forsus appliance. Materials and Methods: 121 records of Class II patients treated with the Forsus appliance were analyzed retrospectively. Cephalograms were traced at three time points. ANOVA was used to compare changes in cephalometric measurements over time. Pearson’s correlation was used to test …

The Fluoride Recharging Capability Of An Orthodontic Primer: An In Vitro Study, Samuel Allen

Theses and Dissertations

Objective: The purpose of this study was to determine the fluoride recharging capability of Opal Seal, a fluoride releasing orthodontic primer, as compared to Transbond XT, the control. Material and Methods: 1mm x 5mm disks of Opal Seal and Transbond were prepared according to the respective manufacturer’s instructions. Initially, the samples were stored in deionized water (DI) for 8 weeks. The samples were then randomly divided into one of two groups: Over-the-counter (OTC) fluoride mouthwash and prescription strength (PS) fluoride mouthwash. The OTC group samples were immersed in 5mL of 0.0219% sodium fluoride containing mouthwash for one minute every day …

Availability Of Dental Anomaly Phenotype In Individuals With Familial Adenomatous Polyposis, Andrea M. Lewis

Dissertations & Theses (Open Access)

Background: Mutations in the APC gene cause familial adenomatous polyposis (FAP), an autosomal dominant colorectal cancer predisposition associated with the development of hundreds to thousands of adenomatous colorectal polyps beginning in childhood or adolescence. Both malignant and non-malignant extracolonic manifestations are associated with APC gene mutations, including approximately 17% of individuals with various dental anomalies. The availability of dental anomaly information in the medical record remains to be evaluated.

Methods: Medical records were reviewed for documentation of dental anomalies. Dental questionnaires were mailed to 271 individuals with FAP at The University of Texas M. D. Anderson Cancer Center (UTMDACC) to …