Dentistry Commons^™

Stress Relaxation In Orthodontic Aligner Plastics; An In Vitro Comparison Study, Kristopher J. Keller

Theses & Dissertations

The purpose of this study was to ascertain if repeated stresses from extension cycling would result in accumulated damage in aligner materials and affect force delivery. A secondary goal was to identify potential differences in mechanical behavior present among orthodontic aligner polymers. Four thermoplastic polymers (Essix ACE, Taglus, Zendura, and Zendura FLX) were thermoformed, cut into strips, and extension cycled to 0.4 millimeters in a 37C water bath. Force decay, maximum and minimum force, and elastic modulus were measured during cycling. Additional samples were subjected to controlled tension until failure, allowing the measurement of yield strength, ultimate strength, and elastic …

Outcomes Of Unilateral Alveolar Clefts Grafted Using Recombinant Human Bone Morphogenetic Protein-2: A Retrospective Volumetric Analysis Using Cbct, Landon Robert Peterson

Theses & Dissertations

Purpose of this study is to evaluate the success rates of secondary alveolar grafts using recombinant human bone morphogenetic protein with CBCT and to evaluate the effects of several variables on these outcomes. After our inclusion/exclusion criteria, records of 24 patients receiving secondary alveolar grafts at the University of Nebraska Medical Center were evaluated. Pre-graft and 6-month post-graft cleft volumes were measured using ITK-SNAP 3.8.0 software to determine a percent residual defect following surgery. Of the 24 patients, one was excluded as the graft surgery was deemed a failure. The patients’ gender, age, side of cleft, cleft side canine root …

Effect Of Nanofiller Coating And Loading On Facial Elastomer Physical Properties, Rahmi K. Aulia

Theses & Dissertations

Current materials used for facial prostheses are far from being desirable, and improved properties with “skin-like” feel are needed. This study evaluates property changes induced by sequential additions of uncoated and hydrophobic-coated nano-SiO₂ to polydimethylsiloxane (PDMS) and compares them with those measured for conventional submicron SiO₂-filled materials. Each filler type was sequentially added to vinyl-terminated PDMS at 0%, 0.5%, 5%, 10%, and 15% by weight. Tensile, tear, Durometer hardness, translucency and viscoelastic properties were evaluated, with hardness and translucency also evaluated following 3000 hours of outdoor weathering. Results demonstrated that 15% coated nano-SiO₂-filled PDMS materials …

Correlation Between Number Of Mendeley Readers And Citations In Dental Sciences, Jafar Kolahi, David G. Dunning, Edward F. Rossomando

Journal Articles: College of Dentistry

No abstract provided.

Do Open Access Dental Articles Enjoy Higher Altmetric Attention Scores, Twitter, Facebook, News, Wikipedia, Blog Mentions, Mendeley Readers And Citations?, Jafar Kolahi, Saber Khazaei, David G. Dunning, Edward F. Rossomando

Journal Articles: College of Dentistry

In order to access articles published in conventional (non-open access) journals, scientists must utilize tools such as subscriptions, site licenses or pay-per-view charges. In contrast, open access articles can be accessed without financial, legal or technical barriers. A large-scale study estimated that at least 28% of the academic literature is open access (19 million in total) and that this percentage is growing.^[1] A recent survey showed an open access rate in field of dentistry at 45.8%.^[2] It has been demonstrated that open access articles had 8% to 40% higher citations compared to non-open access articles; this has been …

Orthodontically Induced External Root Resorption In Extraction Versus Non-Extraction Treatment Modalities – A Retrospective Cone-Beam Computed Tomography (Cbct) Study, Jaykishan Patel

Theses & Dissertations

Purpose of this study was to evaluate orthodontically induced external apical root resorption using cone beam computed tomography in patients receiving orthodontic treatment with or without extractions. Records of 188 consecutively treated patients who received orthodontic treatment with or without extractions were evaluated. Pre-and post-treatment root lengths of maxillary incisors, volumes of maxillary central incisors, and apex displacement of either right or left maxillary central incisors were measured using Invivo 5.4 or ITK-SNAP 3.8.0 software. After adjusting for initial length, treatment duration, tooth, sex, race, bracket type, and malocclusion, maxillary incisor reduction of root length in extraction group was 0.37 …

The Effectiveness Of Resin-Modified Glass Ionomer Varnish In Preventing White Spot Lesions During Fixed Appliance Orthodontic Therapy: An In Vitro Study, Bradley Herman

Theses & Dissertations

The purpose of this investigation was to evaluate the efficacy of a glass ionomer varnish in preventing demineralization of enamel adjacent to and some distance away from an orthodontic bracket. Forty extracted human molars were divided into four different treatment groups (varnish in distilled water, varnish in acetic acid, enamel in acetic acid, and enamel in distilled water). Two 3 x 3 mm graphite windows were drawn on the tooth, one adjacent to the bracket and one 3 mm away from the first window, indicating the scanning area. Varnish was applied to the teeth in the varnish groups and all …

Sarcoidosis Of The Mandibular Condyle: A Rare Disease That Can Mimic Malignancy, Chad Sloan, Ben Lacrosse, Lei Yu, Alexander Braun, Scott Lauer, Timothy Donovan, John Baker, Jason Untrauer

Graduate Medical Education Research Journal

Sarcoidosis can involve any of the organs, however intraosseous involvement is rare and ranges from 5 to 15%, with lesions of the mandible being even rarer – currently with few known cases reported. Intraosseous lesions involving the mandible have been noted to be asymptomatic or associated with chronic jaw pain. Additionally, mandibular involvement can present as a lytic bone lesion mimicking osseous malignancy. Chronic polyarthritis is commonly associated with the progression of sarcoidosis and intraosseous involvement has been considered a late-stage sequelae. We report a case of biopsy-proven sarcoidosis within the mandibular condyle in an asymptomatic 56-year-old Caucasian female who …

Perception Of Bone Mineral Loss On Cone-Beam Computed Tomography (Cbct) & Digital Periapical (Pa) Film: An Ex-Vivo Comparison, David P. Hamm

Theses & Dissertations

Using micro computed tomography (micro-CT) as a reference standard, the purpose of this investigation was to evaluate the influences of bone mineral loss and radiographic contrast in digital periapical (PA) film and cone-beam computed tomography (CBCT). Seven dog and human mandibles were sectioned, followed by modification via cortical bone drilling to create 248 lesions and/or trabecular bone acid demineralization to create 96 coronal slice pairs. Pretreatment and post-treatment radiographs (PA, CBCT, and/or micro-CT) were taken for lesion rating/perception in addition to two-dimensional (area) and three-dimensional (volumetric) measurements of 50 drilling lesions and 20 coronal slice pairs. 4-7% bone mineral loss …

The Effect Of Enamel Matrix Derivative/Papilla Reflection Surgery On The Clinical And Alveolar Bone Outcomes In Periodontal Maintenance Patients, Erica E. Jasa

Theses & Dissertations

The purpose of this study was to determine if local application of enamel matrix derivative (Emdogain; EMD), combined with minimally invasive papilla reflection/root preparation (PR/RP), is effective in improving probe depth (PD), clinical attachment level (CAL), and interproximal bone height (IBH) in persistent 6-9 mm periodontal pockets in patients on periodontal maintenance therapy (PMT). Fifty periodontal maintenance patients with advanced chronic periodontitis presenting with a 6-9 mm interproximal PD were included in study. Experimental (PR/RP+EMD; n=24) and control (PR/RP+S; n=26) therapies were randomly allocated. Roots were treated with reflection of interproximal papillae, root planing assisted with endoscope evaluation, and acid …

The Effect Of Emdogain Periodontal Regenerative Material On Inflammation In Periodontal Maintenance Patients, Jessica M. Gradoville

Theses & Dissertations

The purpose of this double-blinded, randomized, controlled clinical trial was to determine if local application of enamel matrix protein derivative (Emdogain:EMD), combined with minimally-invasive papilla reflection is effective in reducing inflammation in periodontal pockets in patients on periodontal maintenance therapy (PMT).Fifty patients diagnosed with advanced chronic periodontitis presenting with a 6-9mm interproximal probing depth were included in the trial. Experimental (EMD; n=24) and control (saline, n=26) therapies were randomly allocated. Roots were treated with mini-flaps and root planing assisted with endoscope evaluation before EMD or saline application. Inflammation was assessed by bleeding on probing (BOP) at baseline, 6-, and 12-months …

Scientific Landscape Of Dental Literature In 2018, Jafar Kolahi, David G. Dunning, Edward F. Rossomando

Journal Articles: College of Dentistry

In the information age, human medical knowledge continues to grow exponentially, leading us to what could be best described as a knowledge tsunami. In 1950, medical knowledge doubled approximately every 50 years, by 1980, it doubled every 7 years, and by 2010, to a mere 3.5 years. Even more startling, in 2020 human medical knowledge will double in a stunning 73 days.^[1],[2] Nowadays dental professionals face unprecedented information overload and must somehow manage it. Text mining, network visualization, and big data management techniques will help us to analyze and summarize exponentially growing knowledge in field of dentistry. In …

Preprints In Dental Science: Dentrxiv As A Strategy To Bring Dental Research Into The Information Age, Jafar Kolahi, David G. Dunning, Edward F. Rossomando, Elham Bidram, Saber Khazaei

Journal Articles: College of Dentistry

No abstract provided.

Effects Of Class Ii Correctors And Functional Appliances On The Periodontal Health Of The Mandibular Incisors – A Prospective Cone-Beam Computed Tomography (Cbct) Study, David C. Duevel

Theses & Dissertations

The purpose of this investigation was to evaluate the effects of Class II correctors and functional appliances on the dentoalveolar support of the mandibular incisors during orthodontic treatment. Twenty six patients who were treated with a Forsus^TM, Herbst, or MARA participated this study. Lateral cephalometric radiographs, limited field-of-view CBCTs, and periodontal measurements were collected both the day of appliance activation and day of appliance deactivation. Ten hard tissue measurements on all four mandibular incisors were collected at each time point on CBCT images. Bone thickness increased at 6 and 9 mm apical from the cementoenamel junction (CEJ) on …

Changes In The Transverse Dimension Of The Nasomaxillary Complex Following Rapid Palatal Expansion – A Post-Retention, Cbct Evaluation, Allison Schubert

Theses & Dissertations

Purpose: The purpose of this investigation was to evaluate the immediate and long-term effects of palatal expansion on the transverse dimension of the nasomaxillary complex.

Materials and Methods: Twenty-eight patients’ CBCTs were obtained at four time points: pre-expansion (T₁), post-expansion (T₂), pre-treatment (T₃), and middle or end of orthodontic treatment (T₄). The patients’ age, sex, cervical vertebral maturation stage, and the number of instructed expander turns were recorded. Measurements of the nasal floor, nasal passage, maxillary sinus, maxillary first molar mesiolingual cusp, maxillary first molar palatal cusp, maxillary first molar buccal cortical …

Identifying Bias In The Transition From Associate To Dental Practice Owner, David G. Dunning

Journal Articles: College of Dentistry

No abstract provided.

The Effect Of Mechanical Vibration On Pain And Rate Of Tooth Movement During Initial Orthodontic Alignment, Leslie Ellingson

Theses & Dissertations

Purpose: The purpose of this investigation was to evaluate the effect of mechanical vibration on pain experienced and rate of tooth movement (OTM) during the initial alignment phase of orthodontic treatment.

Materials and Methods: Participants were randomly allocated to control, low frequency or high frequency. An electric toothbrush was modified to provide high frequency vibration. A low frequency vibration device was acquired from a commercial vendor. Experimental groups applied vibration to the dentition for 20 minutes daily. All participants completed questionnaires using visual analog scales at five time points. Pain experience was measured in millimeters (mm) with the scale measuring …

Cpap-Mad Combination Therapy For Cpap Intolerant Patients With Moderate To Severe Osa, Jacob Stadiem

Theses & Dissertations

The treatment of obstructive sleep apnea (OSA) allows for a multidisciplinary approach between dentistry and medicine. Continuous positive airway pressure (CPAP) is the gold standard for OSA treatment, but the non-adherence rates are high. The mandibular advancement device (MAD) has a higher acceptance rate than the CPAP, however the efficacy is much lower in cases of moderate to severe OSA. This thesis attempted to evaluate if there was a change in compliance when a MAD was added as a combination therapy to moderate to severe OSA subjects that were currently non-compliant with their CPAP. In addition, the change in air …

Hospital Based Emergency Department Visits With Dental Conditions: Outcomes And Policy Implications In The States Of California, Nebraska And New York, Sankeerth Rampa

Theses & Dissertations

The purpose of this dissertation was to present state-level estimates of hospital-based emergency department (ED) visits with dental conditions across all ages in the states of California, Nebraska, and New York. Also, this dissertation examined the outcomes and impact of changes in Medicaid policies on the utilization of ED with dental problems. State Emergency Department Databases (California, Nebraska, and New York), a component of the Healthcare Cost and Utilization Project (HCUP) was used for this dissertation. Dental conditions were identified by using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. High-risk groups visiting EDs with dental conditions were …

Satisfaction Among Early And Mid-Career Dentists In A Metropolitan Dental Hospital In China, Xiaoxi Cui, David G. Dunning, Na An

Journal Articles: College of Dentistry

A growing body of research has examined career satisfaction among dentists using a standardized instrument, dentist satisfaction survey (DSS). This project examined career satisfaction of early to mid-career dentists in China, a population whose career satisfaction, heretofore, has not been studied. This is an especially critical time to examine career satisfaction because of health care reform measures being implemented in China. A culturally sensitive Chinese-language version of the DSS (CDSS) was developed and electronically administered to 367 early and mid-career dentists in a tertiary dental hospital in Beijing, China. One hundred and seventy respondents completed the survey. The average total …

S4s8-Rpa Phosphorylation As An Indicator Of Cancer Progression In Oral Squamous Cell Carcinomas., Jeff Rector, Sasha Kapil, Kelly J. Treude, Phyllis Kumm, Jason G. Glanzer, Brendan M. Byrne, Shengqin Liu, Lynette M. Smith, Dominick J. Dimaio, Peter J. Giannini, Russell B. Smith, Greg G. Oakley

Journal Articles: College of Dentistry

Oral cancers are easily accessible compared to many other cancers. Nevertheless, oral cancer is often diagnosed late, resulting in a poor prognosis. Most oral cancers are squamous cell carcinomas that predominantly develop from cell hyperplasias and dysplasias. DNA damage is induced in these tissues directly or indirectly in response to oncogene-induced deregulation of cellular proliferation. Consequently, a DNA Damage response (DDR) and a cell cycle checkpoint is activated. As dysplasia transitions to cancer, proteins involved in DNA damage and checkpoint signaling are mutated or silenced decreasing cell death while increasing genomic instability and allowing continued tumor progression. Hyperphosphorylation of Replication …

Articles For The Student Forum, Edward F. Rossomando, Jafar Kolahi, Francesco Chippelli, David G. Dunning, Heejung Bang, Saber Khazaei, Luca Giacomelli, Gunnar Hasselgren, Vuokko Anttonen

Journal Articles: College of Dentistry

No abstract provided.

Effects Of Flash-Free Technique On Plaque Retention, White Spot Lesions, And Bracket Failure: A Randomized Clinical Trial, Payam Ishani Afousi

Theses & Dissertations

A side effect of orthodontic treatment is the development of white spot lesions (WSLs). This thesis attempted to evaluate the effects of the use of APC™ Flash-Free (FF) and conventional adhesives in bonding of orthodontic brackets on plaque formation and retention, WSL development, and bracket failure in-vivo. This was accomplished by collecting plaque samples from around orthodontic appliances and analyzing them using ATP-driven bioluminescence; scanning enamel surfaces using the Canary System™ to evaluate WSL development, and counting the number of spontaneous debonding of brackets of the 4 maxillary incisors in the first 6 months of treatment. It was found …

Bone Loss Quantification Following Extraction In Rats: A Foundation For Grafting And Regenerative Studies, Emily Willett

Theses & Dissertations

Background: Loss of the alveolar ridge width and height following extraction is well-documented and several techniques, including grafting, have been proposed to reduce bone loss. Purpose: To characterize the pattern of bone turnover and inflammation after extraction and to initiate a study of the effect of grafting and local administration of simvastatin (SIM). Methods: Thirty-two retired-breeder rats underwent extraction of the right maxillary first molar and standard surgical defect creation under inhalation anesthesia. The left side of each animal served as the unmanipulated control. Comparison of groups (n=8, ANOVA) was done at days 0, 7, 14, and …

Local Minocycline To Reduce Future Inflammation And Bone Loss In Periodontal Maintenance Patients, Jeffery S. Jensen

Theses & Dissertations

The objectives of this study were to compare the effect of SRP+MM versus SRP alone on inflammatory cytokines, interleukin (IL)-1β and IL-1 receptor antagonist (ra), found in gingival crevicular fluid (GCF) and saliva, and correlate IL-1 values with clinical outcomes over a 2-year period of PMT. Fifty-five patients with an initial posterior pocket ≥5 mm and history of bleeding on probing (BOP) were randomized to test (SRP+MM, n=27) and control (SRP, n=28) groups. Clinical measurements and GCF samples were done at baseline and 24 months. SRP+MM or SRP were provided at 6-month intervals. IL-1β and IL-1ra were measured in GCF …

Color Stability, Physical Properties And Antifungal Effects Of Zro2 And Tio2 Nanoparticle Additions To Pigmented Polydimethylsiloxanes, Mazen Alkahtany

Theses & Dissertations

Introduction: Color changes, physical degradation and fungal infections are potential challenges to the longevity of polydimethylsiloxane (PDMS) elastomers. The purpose of this study was to evaluate potential improvements in color change, physical properties and anti fungal properties of PDMS loaded with TiO2 and ZrO2 nanoparticles.

Methods: 1% weight of 40 nm or 200 nm diameter TiO2 or ZrO2 nanoparticles were mixed into PDMS with 2% functional intrinsic yellow pigment and polymerized. Control materials contained 13% weight 200 nm silica. Samples were exposed to either 3000 hours of UVB radiation (200 μW/cm2) or darkness. Color parameters L*a*b* and ΔE*, ultimate tensile …

Squamous Cell Carcinoma Response To Cisplatin Exposure, Khanh V. Luong

Theses & Dissertations

Purpose: This thesis attempted to quantitatively analyze the individual cell fate choice in resistant head and neck UM-SCC38 cells exposed to cisplatin using the most current techniques available.

Methods: UM-SCC-38 cells were grown in Dulbecco’s modified Eagle’s medium (DMEM) supplemented with 10% fetal bovine serum (FBS). They were treated with cisplatin and ATM/ATR inhibitors of known dosages. Using live cell imaging, one hundred cells were tracked in each experiment and their behaviors were analyzed and entered into Microsoft Excel Spreadsheet to generate cell profile graphs. HaCaT cells, non-tumorigenic keratinocyte cell line, were also analyzed using live cell imaging and their …

Effect Of Dexamethasone Prodrug On Inflamed Temporomandibular Joints In Juvenile Rats., Mitchell Knudsen, Matthew Bury, Callie Holwegner, Adam L. Reinhardt, Fang Yuan, Yijia Zhang, Peter J. Giannini, David B. Marx, Dong Wang, Richard A. Reinhardt

Journal Articles: College of Dentistry

INTRODUCTION: Juvenile idiopathic arthritis (JIA) often causes inflammation of the temporomandibular joint (TMJ) and has been treated with both systemic and intra-articular steroids, with concerns about effects on growing bones. In this study, we evaluated the impact of a macromolecular prodrug of dexamethasone (P-DEX) with inflammation-targeting potential applied systemically or directly to the TMJ.

METHODS: Joint inflammation was initiated by injecting two doses of complete Freund's adjuvant (CFA) at 1-month intervals into the right TMJs of 24 growing Sprague-Dawley male rats (controls on left side). Four additional rats were not manipulated. With the second CFA injection, animals received (1) 5 …

Effect Of Chemical Pocket Disinfection As An Adjunct To Non-Surgical Maintenance Therapy Of Inflamed Periodontal Pockets, Chad Riggs

Theses & Dissertations

Purpose: Scaling and root planing with adjunctive chemical pocket disinfection (SRP+C) utilizing sodium hypochlorite solution has been used to treat inflamed pockets of periodontal maintenance patients for many years, without evidence of its benefits. The primary objective was to determine if SRP+C is more effective than scaling and root planing alone (SRP) in improving clinical outcomes. The secondary objective was to compare the effect of SRP+C and SRP on pro-inflammatory IL-1β, anti-inflammatory IL-1ra, and anti-inflammatory index (IL-1ra/IL-1β ratio) found in gingival crevicular fluid (GCF).

Materials and Methods: Pockets (≥ 5 mm and BOP) of 31 maintenance patients were included. Test …

Prevention Of Experimental Periodontitis In Rats With A Simvastatin Prodrug, Aaron Bradley

Theses & Dissertations

Introduction: Simvastatin (SIM) is a hypolipidemic drug that has been shown to have anti-inflammatory and bone anabolic properties. The aim of this study was to examine the effects of novel locally-applied SIM conjugated with methoxypolyethylene glycol to form micelles (SIM/SIM-mPEG) in an experimental periodontitis model in rats using micro-computed tomography (µ-CT) and histologic evaluation.

Methods: Experimental periodontitis was induced using silk ligatures around the maxillary right second molar (M2) in 40 Sprague-Dawley rats. Rats were divided into five groups using SIM/SIM-mPEG at 0.5, 1.0, or 1.5 mg SIM doses, mPEG-alone or no drug (ligature-alone) injected into the palatal M1-M2 gingiva …