The Effect Of Crowding On The Accuracy Of 3d Printed Aligners, Tonya Spangler

Theses and Dissertations

Purpose: To evaluate the accuracy of three-dimensionally (3D) printed aligners compared to conventional vacuum-formed thermoplastic aligners with varying levels of dental crowding.

Methods: Digital intraoral scans of 10 different cases were assigned to their respective groups (n=10, each, 30 total) as follows: no crowding (control), moderate crowding, and severe crowding. Using 3Shape software, digital aligner samples were created in standard tessellation language (STL) file format and randomly 3D printed. The same STL files of each case were also sent to a dental laboratory for the fabrication of vacuum-formed samples, which is the current technology used for manufacturing aligners. The intaglio …

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 …

The Efficacy Of A Fluoride-Containing Orthodontic Primer In Preventing Demineralization, Alyssa G. Ricci

Theses and Dissertations

Purpose: To evaluate the efficacy of a fluoride-containing orthodontic primer in preventing demineralization adjacent to brackets and compare the quality of enamel on tooth surfaces that received interproximal reduction (IPR).

Methods: Patients at the VCU Orthodontic clinic who consented to orthodontic treatment involving extraction of at least 2 premolars were recruited to this pilot clinical study. Brackets were bonded to premolars using one of two primers, fluoride-containing experimental or control. IPR was also performed, and the experimental primer was applied to randomly selected teeth. Extracted teeth were analyzed visually for the presence of white spot lesions (WSLs). Micro-CT analyses were …

Effect Of Shear Bond Strength With Novel Apc™ Flash-Free Brackets And Different Bonding Protocol: An In Vitro Study, Carl Bernstein

Graduate Theses, Dissertations, and Problem Reports

Background and Objectives: In today’s time, there is an increasingly crowded field of competition vying over a small subset of the population. Now, more than ever it is imperative to compete with efficiency and esthetics. Each step for orthodontic bonding procedures increases the chance for error to occur. However, orthodontic bracket, etchant, sealant, and adhesive material has the ability to improve bond strength and final outcome for the patient and provider. The aim of this study was to determine effective bonding protocols for Advanced Clarity APC™ Flash-Free Brackets and to determine if adhesive remains on enamel or orthodontic bracket after …

Effect Of Clear Aligner Therapy On Masticatory Muscle Tenderness And Orthodontic Pain, Johnny Tran

Electronic Thesis and Dissertation Repository

Introduction: Patients undergoing orthodontic clear aligner therapy (CAT) may experience discomfort in their teeth and jaws, and often present with visible wear on their aligners. This multi-site prospective clinical study aimed to analyze tooth pain and masticatory muscle tenderness in patients subjected to CAT with Invisalign©.

Methods: Twenty-seven healthy adults undergoing treatment with Invisalign© were recruited from three university-based orthodontic clinics. Tooth pain and muscle tenderness were reported on visual analog scales in pain diaries prior to, and after starting CAT. Pressure pain thresholds (PPT) measured using pressure algometers were used to assess somatosensory changes in trigeminal and extra-trigeminal locations. …

Orthodontic Bond Strength Comparison Between Two Filled Resin Sealants, James Kolstad

Master's Theses (2009 -)

Introduction: Sealants are used in orthodontics to help prevent demineralization during treatment. The objective of this study was to determine if there is a difference in the shear bond strength (SBS) between two different resin sealants bonded to teeth. Materials and Methods: Extracted human premolars (n=20/group) were randomly divided and prepared by acid etching, followed by application of primer or sealant. Group 1, the control group, used Transbond XT Primer (3M Unitek). Groups 2 and 3 were prepared with the sealants L.E.D. Pro Seal (Reliance Orthodontic Products) and Opal Seal (Opal Orthodontics) respectively. Transbond XT Adhesive was applied to a …

Evaluation Of Fit For 3d Printed Retainers As Compared To Thermoform Retainers, David J. Cole

Theses and Dissertations

ABSTRACT

EVALUATION OF FIT FOR 3D PRINTED RETAINERS AS COMPARED TO THERMOFORM RETAINERS

By David Cole, D.M.D.

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Dentistry at Virginia Commonwealth University

Thesis Directors: Eser Tüfekçi, D.D.S., M.S., Ph.D., M.S.H.A.

Professor, Department of Orthodontics

Sompop Bencharit, D.D.S., M.S., Ph.D.

Associate Professor and Director of Digital Dentistry, Department of General Practice

Introduction: Despite recent advances in three-dimensional (3D) printing, little information is available on 3D printed retainers

Methods: Three reference models were used to fabricate traditional vacuum formed, commercially-available vacuum formed, and 3D printed …

Binding Of Salivary Proteins To Orthodontic Brackets, Maria Pia Canales

Electronic Thesis and Dissertation Repository

Objectives: The aim of this study was to investigate the effect of different orthodontic materials on the formation of the protein pellicle on the bracket surface.

Materials and Methods: We used X-ray Photoelectron Spectroscopy (XPS) to analyze the atomic composition of orthodontic metallic and ceramic brackets. Following XPS, the brackets were immersed in human whole saliva supernatant for 2-hour incubation at 37°C. Hydroxyapatite (HA) discs were used as control. Acquired pellicle was harvested with sonication for each group, and liquid chromatography electrospray ionisation mass spectrometry was used for protein identification.

Results: Differences reported by XPS and mass spectrometry were noted …

Thermal Properties Of Commonly Used Clear Aligner Systems As-Received And After Clinical Use, Louis Wenger

Master's Theses (2009 -)

Background/Objectives: The purpose of this study was to investigate the thermal properties, particularly glass transition temperature, of the polymers that are used to fabricate three different types of modern orthodontic aligners. Invisalign, (Align Technology, Inc, Santa Clara, CA, USA), Simpli5 (Allesee Orthodontic Appliances, Sturtevant, WI, USA), and ClearCorrect (ClearCorrect, Round Rock, TX, USA) were examined both as-received and after clinical use to determine if any differences were present both between and within aligners. Materials/Methods: Orthodontic aligners were collected from three different patients using the systems under investigation after two weeks of intraoral use. Duplicate, un-used samples were obtained from the …

The Effect Of Heat Treatment On The Bending Properties Of A Cobalt-Chromium Orthodontic Wire, Alex Schwab

Master's Theses (2009 -)

Introduction: Elgiloy, a brand name of the original cobalt-chromium orthodontic wire, has been around for more than 50 years; yet despite this, little literature is available. Most of the literature on Elgiloy wires tends to evaluate the wires in tension. For these reasons, this study aimed to determine the bending properties of the four available tempers of Elgiloy wires and how heat treatment affects the wires’ bending properties. Materials and Methods: All four tempers of Elgiloy (red, yellow, green, and blue) were ordered in straight lengths containing 20 wires per pack that are each 0.018 inches in diameter and 14 …

An Investigation Of Surface Characteristics Of Enamel Treated With Infiltrative Resin: A Scanning Electron Microscopy Study, Danielle E. Easterly

Theses and Dissertations

AN INVESTIGATION OF SURFACE CHARACTERISTICS OF ENAMEL TREATED WITH INFILTRATIVE RESIN: A SCANNING ELECTRON MICROSCOPY STUDY

Danielle E. Easterly, Doctorate of Dental Surgery.

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Dentistry at Virginia Commonwealth University.

Virginia Commonwealth University. 2017.

Director: Dr. Eser Tüfekçi

D.D.S., M.S., Ph.D., M.S.H.A.

Objective: To evaluate the microstructural changes of a resin infiltrant (ICON®, DMG America LLC, Englewood, NJ) after six months of simulated toothbrushing.

Materials and Methods: Ten extracted third molars (n=10) were collected. Artificial white spot lesions were created and resin applied. Environmental SEM …

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 …

Correlation Of Tooth Length Measurements Made On Cbct And 3t Mr Images, Andrew Scott Taylor

Loma Linda University Electronic Theses, Dissertations & Projects

Objective. This study compared tooth length measurements made on cone beam computed tomography (CBCT) scans and 3-Tesla (3T) magnetic resonance (MR) scans performed with and without an alginate bite registration surrounding the crowns of the teeth. Materials and Methods. One CBCT scan, one MR scan with alginate bite registration, and one MR scan without bite registration were performed on 12 subjects. The alginate bite registration was used to provide a proton-rich material to surround proton-poor teeth in an attempt to improve visualization of teeth. DICOM formatted images from each of the three scans for each subject were oriented in all …

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 …

Thermomechanical Characterization Of Variable Force Niti Orthodontic Archwires, Anjali Sudershan Krishan Mehta

Master's Theses (2009 -)

ABSTRACT THERMOMECHANICAL CHARACTERIZATION OF VARIABLE FORCE NITI ORTHODONTIC ARCHWIRES Anjali Mehta, BDS MDS Marquette University, 2015 Introduction: Nickel-Titanium (NiTi) archwires, due to their properties of superelasticity and shape memory, have been extensively used in orthodontic mechanotherapy. However, one of the shortcomings of these wires is that they deliver constant forces across the entire arch. The amount of force needed to move a tooth is a function of the surface area of the tooth and its supporting bone; and is lesser for single rooted anterior teeth compared to larger molars. The introduction of heat treatment of NiTi wires and the influence …

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 …

Changes In Composite Toxicity Following Exposure To Pulp Capping Materials, Audra Long

Master's Theses (2009 -)

Introduction: Direct pulp capping involves placing a material over the exposed pulp in order to maintain its vitality. For decades, calcium hydroxide (CH) has served as the gold standard for this purpose, but its toxicity to the pulp may negatively impact treatment outcomes. Mineral Trioxide Aggregate (MTA) has become a popular alternative based partly on its excellent biocompatibility. Pulp-capped teeth are often restored with highly toxic composite materials, but the pulp capping material’s ability to alter these toxic effects has never been investigated. The purpose of this in vitro study is to determine the effects of Dycal, a CH-based cement, …

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 …

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 …

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) …

Effect Of Gingival Margin Design On Retention Of Thermoformed Orthodontic Aligners, Daniel P. Cowley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Purpose: The aim of this study was evaluate the effect of gingival margin design (scalloped vs. straight cut at gingival zenith vs. straight cut 2mm above gingival zenith) on the retention of thermoformed aligners. Retention of aligners is a critical requirement for efficient tooth movement.

Methods: Two thermoform aligner materials were used, Invisacryl A and Invisacryl C, in 0.040 mil (1mm) thickness. Six aligner designs were fabricated for each of the two aligner materials (12 total aligner designs). Aligner designs are scalloped, straight cut at gingival zenith (0mm), and straight cut 2mm above gingival zenith on a model with attachments. …

Effect Of Toothbrush Abrasion On Frictional Resistance Of Aesthetic Orthodontic Archwires, Stephen Alexander Yamodis

UNLV Theses, Dissertations, Professional Papers, and Capstones

Fixed orthodontic appliances (braces) are one of the most widely used appliances to correct malocclusion, however many patients prefer less metal display. To meet this demand more esthetically pleasing brackets and archwires have been developed. These esthetic components are often clear, white or tooth colored. Coatings of various types are commonly used to produce an esthetic archwire. However, these coating materials tend to wear and degrade, which may cause binding and increased resistance to friction, thereby potentially reducing the efficiency of tooth movement. Therefore, in vitro testing of tooth brush abrasion on frictional resistance of various aesthetic archwires was tested. …

Practicing Orthodontists' Use And Perceived Efficacy Of Self-Ligating Brackets, John-David Beuhler

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction.

The purpose of this study was to compare perceptions of efficacy and efficiency of Self-Ligating Brackets vs. conventional brackets between practicing Orthodontists and Orthodontic Residents.

Methods.

Cross-sectional survey research using a three-wave emailing of addresses from the current American Association of Orthodontists directory. The directors of all orthodontic residency programs in the US were asked to also distribute to all residents. The survey included five sections: (1) respondents' experience, (2) factors that influence, (3) positive or negative factors, (4) the perceived efficiency/efficacy, and (5) demographics. A 39% response rate (N=707) was obtained.

Results.

Over half (51.8%) …

Bacterial Adherence Of Streptococcus Mutans And Lactobacillus Acidophilus On Poly-Methyl Methacrylate And Thermoplastic Polypropene Used In Orthodontic Retention, Lindsay Ann Pfepper

UNLV Theses, Dissertations, Professional Papers, and Capstones

Retention is required in the majority of orthodontic patients throughout the remainder of their life. The two primary removable appliances are known as the traditional Hawley retainer or the vacuum formed retainer. These appliances were developed to maintain the position of the dentition without sacrificing oral health. The orthodontic population is at a higher risk for caries due to plaque accumulation from poor diet, suboptimal oral hygiene and often lack of motivation. These two retainers occupy different niches and are comprised of different materials; therefore the retainers' effect on oral health could be very different. An understanding of which bacteria …

Work Of Fracture In Ceramic Bracket Bonding Systems, Tye A. Roylance

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Work of fracture (WOE) is a method of analysis of the toughness or resilience of a bracket bonding system. It is an indication of a bracket bonding systems ability to withstand forces in the mouth below the force at which failure occurs. Work of fracture gives an indication of how much abuse the bracket/bonding system can withstand and still maintain an adequate adhesion to the tooth surface. This analysis incorporates shear bond strength and displacement and is determined in part by the elasticity and resilience of the specimen being studied.

Materials and Methods: One hundred and eighty bovine teeth …

Dentoskeletal And Soft Tissue Treatment Effects Of Two Different Methods For Treating Class Ii Malocclusions., Madhur Upadhyay

Master's Theses

Objectives: Moderate to severe Class II malocclusions can not only cause esthetic and functional problems but can also lead to psychological problems of varying intensity depending on the amount of anterior-posterior discrepancy and its interaction with the related soft tissue structures. Although there are several methods of treating such malocclusions (extractions,distalization,functional appliances etc), the final goal is always to provide acceptable esthetics and stability. The purpose of this clinical-cephalometric study was to examine the dentoskeletal and soft tissue treatment effects of maxillary anterior teeth retraction with mini-implant (MI) anchorage in young adults having Class II Division I malocclusion undergoing extraction …

Influence Of Stainless Steel Orthodontic Brackets On Magnetic Resonance Imaging, Christian James Hoybjerg

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Magnetic resonance imaging (MRI) machines provide 2D as well as 3D images that are excellent in contrasting soft-tissue in the maxillofacial region and are void of ionizing radiation. The drawbacks include the lack of depiction of cortical bony detail and image degradation caused by substances in the scanned area. Specifically, in the orthodontic field stainless steel brackets cause more distortion of MR images then any other bracket material. It is unknown what type of stainless steel alloy causes the most MRI distortion. The purpose of this study is to evaluate the degree of craniofacial MR distortion caused by various …