Digital Commons Network^™

Maxillary And Mandibular Incisor And Molar Dentoalveolar Heights In Untreated Subjects Presenting Class I And Class Ii Malocclusion, Samantha Zavada Cardinal

Master's Theses (2009 -)

Objective : Class II malocclusion has been extensively studied, however there are many unanswered questions. This study analyzed the difference in incisor and molar dentoalveolar heights of untreated subjects presenting with Class I and Class II malocclusion. Dentialveolar heights are an aspect of the craniofacial complex that changes with growth and development and are manipulated by orthodontists. These changes hold important clinical implications for the development, maintenance and treatment of malocclusions. Methods : A sample of 96 untreated Class I and Class II subjects, with a total of 611 cephalograms was drawn from the archives of the University of Michigan …

Mechanism Of Mechanical Vibration In Enhancing Orthodontic Retention- Analysis Of Global Gene Expression, Shuwei Wang

Master's Theses (2009 -)

Introduction: Low-magnitude, high-frequency (LMHF) mechanical vibration has been proposed as a possible adjunctive retention method after orthodontic treatment. In this study, we explored the mechanism of using LMHF vibration to improve bone formation during retention phase. We aimed to provide insight of global gene expression and cellular activities of PDL cells under tension, as well as identify novel biomarkers for induced osteogenesis by using LMHF mechanical vibration as adjunct tool in retention phase. Materials and Methods: Human PDL cells (hPDLCs) were seeded in 6-well FLEXCELL culture plates. The wells were assigned to four experimental groups as control, stretching (ST), vibration …

Evaluation Of Damon Psl And Conventional Mbt Brackets In Leveling And Alignment Efficiency, Jacob Beckstrand

Master's Theses (2009 -)

Objective: Ormco has proposed that the low-friction design of their self-ligation brackets allows for more efficient alignment of crowded teeth with less incisor proclination and faster treatment times compared to conventional MBT bracket systems. The purpose of this study is to examine the hypothesis that there is no difference between Damon PSL and conventional MBT brackets in factors related to leveling and alignment in-vitro. Methods:Damon Q2 .022” slot brackets and 3M Unitek .022” slot MBT brackets were bonded to 2 sets of typodont teeth. Typodont teeth were placed into 8 upper and lower Class I crowding wax forms (Kilgore, USA) …

Effects Of Cleaning Agents On The Properties Of Two Different Thermoplastic Retainer Materials, Jennifer Brehove

Master's Theses (2009 -)

Objective: There are several different thermoplastic retainer materials and cleaning methods available to fabricate and clean clear retainers. Some studies have investigated the changes in properties of clear retainers after being exposed to different staining agents, varying levels of mechanical strain, and different cleaning agents. However, there are few studies that compare different thermoplastic materials to each other when being subjected to these different types of stresses. The aim of this study is to evaluate the changes in properties of two commonly used thermoplastic retainer materials, polyethylene terephthalate (PETG) and ethylene/propylene (EP), after exposure to different retainer cleaning agents over …

Effect Of Heat-Treatment Time On Bending Properties Of Cobolt-Chromium Orthodontic Wires, Melanie Hammerbeck

Master's Theses (2009 -)

Different protocols appear in the literature with respect to heat-treating cobalt-chromium orthodontic wires. The objective was to determine the effect of variable heat-treatment time and method on the bending properties of CoCr wires. Two tempers of CoCr ‘Elgiloy’ wires (Rocky Mountain Orthodontics), blue (B) and yellow (Y), were heat-treated for different durations. The groups (n=20/group/temper) included: 1) as-received (control); 2) brush-flame; 3) 480oC for 5sec; 4) 480oC for 10min; 5) 480oC for 2hr; and 6) 480oC for 5hr. Wire segments were tested by a three-point bend test. Stiffness/flexural modulus, percent recovery, and force values at select deflections were statistically compared …

Efficacy Of Invisalign Attachments: A Retrospective Study, Theresa Karras

Master's Theses (2009 -)

Objective: To compare the efficacy of Invisalign’s (Align Technology, Inc., Santa Clara, CA) optimized and conventional attachments on rotational and extrusive tooth movements.Materials and Methods: Initial, predicted, and achieved digital dental models from 100 orthodontic patients were exported from Invisalign’s ClinCheck software as stereolithography (STL) files and subsequently imported into the Slicer CMF program (open source, version 4.7.0) for superimpositions on posterior teeth with no planned movement. Rotational and extrusive measurements for both optimized and conventional attachment types were made on 382 teeth from the superimposition of the initial and predicted models (“predicted movement”) and from the superimposed initial and …

Comparison Of Immediate Vs. Delayed Recall Of Orthodontic Information Following An Electronic Reminder, Michael Lenz

Master's Theses (2009 -)

Patients and parents in dentistry often do not remember important information disclosed during the informed consent process, so improvement in the delivery of information is needed. This study explored the effect of an emailed narrated instructional PowerPoint on the immediate vs. delayed recall and comprehension of informed consent information in orthodontics. Thirty-two subjects were recruited from a university and private practice orthodontic clinic. At the initial visit, subjects were alternately assigned to one of two groups and were presented with a mock orthodontic treatment plan and informed consent presentation for a pretend patient. Immediately following the presentation, the subjects’ verbal …

Direct Visual Approximation Of Arch Length Discrepancy And Cephalometric Measurements, Bradley J. Wurm

Master's Theses (2009 -)

Introduction: Arch length discrepancy and cephalometric analysis are critical components of orthodontic treatment planning. Both have direct effects on the decision to extract teeth or not and treatment mechanics as well. Visual approximation is the most common method used to analyze arch length discrepancy among practitioners. Current trends show a decrease in the amount of orthodontists completing a cephalometric analysis. Previous studies have shown a tendency for orthodontists to overestimate the degree of crowding when visually approximating on dental casts. No previous study has assessed the ability to visually approximate cephalometric angle measurements. The purpose of this survey was to …

Mechanical Properties Of Copper-Nickel-Titanium Archwires, Margaret Amelia Rosen

Master's Theses (2009 -)

Introduction: The initial phase of orthodontic therapy relies on flexible wires, usually composed of a nickel-titanium alloy, to apply a substantially constant load during tooth movement. Copper has been added to nickel-titanium archwires, resulting in an alloy with potential clinical advantages such as a lower stress hysteresis. Many orthodontic companies claim that their copper-nickel-titanium manufacturing process allows for the production of more consistent transition temperatures in the wires, allowing the orthodontist to customize treatment to various patients based on the force level needed. There are currently many manufacturers of these wires, creating a wide range of copper-nickel-titanium archwires from which …

Thermal Properties Of Copper Nickel-Titanium Orthodontic Archwires, Joshua Gilbert

Master's Theses (2009 -)

Introduction: Copper Nickel-Titanium (CuNiTi) is a relatively new composition of Nickel-Titanium (NiTi) archwires that was originally patented in 1991 as part of the Ormco line of wires. The patent has now recently expired and many other orthodontic companies are making their own CuNiTi wires. Advertisement claims have focused on the laboratory benefits of adding Copper (Cu) to the NiTi, however few independent laboratory testings have been conducted on these new wires to verify claims. The purpose of this study was to conduct thermal analysis of CuNiTi for all currently available wires in two Austenite Finish (Af) variants and two commonly …

The Effect Of Orthodontic Appliances On The Evaluation Of The Professionalism And Esthetics Of An Adult Employee, Laura Hanson Vaccariello

Master's Theses (2009 -)

This study explored the influence of fixed and removable orthodontic appliances on participants’ ratings of the job performance, intelligence, and attractiveness of an adult female. Ninety-four adult subjects were recruited from the Graduate School of Management at Marquette University. Each subject received an identical employee performance review with an attached photograph of a female employee. The smile of the photo was manipulated to represent one of four conditions: no orthodontic appliance, a metal orthodontic appliance, a ceramic orthodontic appliance, or a clear aligner. Subjects then rated the employee on three continuous Likert scales. Ratings of job performance, intelligence, and attractiveness …

Influence Of Fluoride And Stress On The Mechanical Properties Of Nickel-Titanium Coils, Jennifer Ann Fehrman Roloff

Master's Theses (2009 -)

Objective: The objective of this study was to determine the influence of fluoride and stress on the mechanical properties of nickel-titanium open coil springs. Materials and Methods: Sentalloy nickel-titanium open coil springs (15 mm length) were divided into five groups. A control group was tested mechanically in as-received condition. The other four experimental groups were exposed to artificial saliva (Fusayama-Meyer solution) at 37oC for 12 weeks in a 2x2 factorial design with fluoride exposure and stress (compression) as the two factors. Those springs which were under compression were held at 5 mm in length for the entirety of the testing …

The Direct Effect Of Low-Magnitude High-Frequency Mechanical Vibration On Osteoclast Formation From Raw267.4 Monocytes, Maxwell Antonio Abraham

Master's Theses (2009 -)

Low-magnitude high-frequency (LMHF) mechanical vibration has been demonstrated to enhance bone formation possibly through inhibition of osteoclastogenesis of bone. Earlier research has demonstrated osteoclast formation from RAW264.7 monocytes was inhibited by a chewing cycle mimicking vibration through inhibition of dendritic cell-specific transmembrane protein (DC-STAMP). We hypothesize that application of LMHF mechanical vibration directly inhibits osteoclast formation from RAW264.7 monocytes in a frequency dependent manner. RAW264.7 monocytes (ATCC) were cultured in alpha minimal essential medium (MEM) with 10% fetal bovine serum (FBS ) and 1% Pen/Strep at 37°C and 5% CO2. The cells were seeded at a density of 2000 cells/well …

Influence Of Fluoride And Stress On The Electrochemical Properties Of Nickel-Titanium Coils, Ashley Barnes

Master's Theses (2009 -)

The aim of this study was to examine the effects of fluoride and stress on the electrochemical properties of nickel-titanium coils. Forty Dentsply GAC NiTi coils were divided into four groups of ten and individually tested. Twenty coils were placed in a solution of artificial saliva, where ten of the twenty were compressed and the other ten were not stressed. The other twenty coils were placed in a 1500 ppm NaF solution, where ten were compressed and ten were not. The coils were connected to a computer driven potentiostat and three tests were conducted: open circuit potential monitoring for 2 …

Mechanical Properties And Patient Perceptions Of Commonly Used Clear Aligner Systems As-Received And After Clinical Use, Lauren Evan Montoure Teske

Master's Theses (2009 -)

Background/Objectives: This study aimed to investigate the viscoelastic properties of two clear aligner systems, Invisalign (Align Technology, Inc, Santa Clara, CA, USA) and Simpli5 (Allesee Orthodontic Appliances, Sturtevant, WI, USA), and determine if there was a difference after use. A survey assessed patients’ perceptions of the aligner material and post-treatment satisfaction. Materials/Methods: Mandibular aligners were collected from two patients after 2-3 weeks of use (n=6). Duplicate, unused aligners were obtained for each patient (n=6). Dynamic mechanical analysis (DMA) characterized the viscoelastic properties of the materials. Three tests were done on separate specimens: frequency scan (0.1-10 Hz under 25 μm displacement …

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 …

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 …

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 …

Intra- And Inter-Examiner Reliability And Inter-Method Comparison In Physical Anthropometry And Photogrammetry, Nikolay Mollov

Master's Theses (2009 -)

Objective: Orthodontic treatment can often effect changes in the facial complex. In order to assess what those changes are, precise and reliable methods for measuring facial structures need to be used. While the techniques used for measuring have become increasingly more sophisticated they have also become more expensive and cumbersome for daily use. This study investigated the reliability of two methods, physical anthropometry and photogrammetry, that were inexpensive and relatively easy to set up.

Materials and Methods: Ten examiners measured a sample comprised of 20 dental students (10 male, 10 female) twice over three weeks. Eighteen measurements were acquired directly …

The Effect Of Extracorporeal Shock Wave (Esw) On Cementoblasts In Vitro, Joshua Barta

Master's Theses (2009 -)

Root resorption is an adverse consequence of orthodontic treatment, and currently no effective treatment method exists. Extracorporeal shock wave (ESW) has been applied to enhance angiogenesis, growth and healing of bone, but the effects of ESW on root resorption have not been studied. Cementoblasts are the cells responsible for forming and repairing cementum covering the dental root, and ESW may enhance this reparative process. The purpose of this study was to investigate the effects of ESW on cementoblasts to determine if ESW could potentially be used to treat root resorption. OCCM.30 cementoblasts were prepared in suspension at a density of …

Friction Testing Of A New Ligature, Alison Mantel

Master's Theses (2009 -)

Objective: To determine if American Orthodontics' (AO) new, experimental ligature demonstrates less friction in vitro when compared to four other ligatures on the market.

Methods: Four brackets were mounted on a custom metal fixture allowing an 0.018-in stainless steel wire attached to an opposite fixture with one bracket to be passively centered in the bracket slot. The wire was ligated to the bracket using one of five types of ligatures including the low friction test ligatures (AO), conventional ligatures (AO), Sili–TiesTM, Silicone Infused Ties (GAC), Synergy® Low-Friction Ligatures (RMO), and SuperSlick ligatures (TP Orthodontics). Resistance to sliding was measured over …

Cementoblastic Response To High Vs. Low Level Of Mechanical Force In Vitro, Natalie Nicole Mullally

Master's Theses (2009 -)

One of the possible complications of orthodontic treatment is apical root resorption. During orthodontic treatment, as the teeth are being moved, the alveolar bone is continually being modeled to accommodate the teeth. This process activates specific cells that are responsible for bone resorption and can have the unwanted effect of resorbing the apex of the tooth root adjacent to the bone. It is unclear exactly what aspects of orthodontic treatment may trigger the resorptive process. A positive correlation, however, between root resorption and mechanical loading applied during orthodontic tooth movement has been established implicating orthodontic treatment in this adverse effect. …