Dental Materials Commons^™

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 …

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 …

Viability Of Human Periodontal Ligament Fibroblasts After Time In Tooth Storage Media, Scott Macdonald

Master's Theses (2009 -)

Periodontal ligament cell viability at the time of tooth replantation is of utmost importance for proper repair of the damaged tissues (1). Multiple different options are currently available for storage of an avulsed tooth. The goal of this study was to investigate new storage media and evaluate their ability to maintain cell viability over time. Materials and Methods: Cultured human periodontal ligament fibroblasts (hPDLF) were seeded on 96-well plates. These cells were exposed to different storage media including: Hank’s Balanced Salt Solution (HBSS), EMT Toothsaver (EMT), Save-A-Tooth (SAT), trehalose (T300), cell culture media, water, and different formulations of HBSS combined …

Color Change Of Commercial Resin Composited With Different Photoinitiators, Feng Gao

Master's Theses (2009 -)

Camphorquinone (CQ) is the most commonly used photoinitiator in light-cured dental resin composites. However CQ is associated with a yellowing effect, which has led manufacturers to add alternative initiators into resin composites to reduce the amount of CQ used. The color change upon polymerization by light and aging in artificial saliva and room air of 8 commercial traditional or bulk-fill resin composites with or without additional photoinitiator(s) beside CQ was studied. The three traditional resin composites with CQ and additional photoinitiator(s) tested were Tetric EvoCeram (Ivoclar Vivadent), AELITE LS Posterior (Bisco), and Vit-l-escence (Ultradent). The two bulk-fill resin composites with …

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 …

Torsion And Bending Properties Of Edgeendo Files, Chad Hansen

Master's Theses (2009 -)

Introduction: One important step of root canal therapy is the process of cleaning and shaping each canal. This process involves using endodontic rotary files combined with chemical irrigants to remove pulpal remnants and infected dentin from the canal while eliminating pathogenic bacteria. It is essential to maintain proper canal anatomy while cleaning and shaping. The challenge for the practitioner is to select a rotary file system that will be flexible enough to maintain canal anatomy but strong enough to prevent breakage under normal use. File flexibility allows for better maintenance of canal anatomy. A file’s resistance to torsional fatigue reduces …

Viability Of Human Periodontal Ligament Fibroblasts After Storage In Save-A-Tooth, Emt Toothsaver And Hank's Balanced Salt Solution, Wonhee Lee

Master's Theses (2009 -)

Introduction: Viability of periodontal ligament (PDL) cells is a key prognostic factor fora replanted tooth following avulsion. Dehydration results death of PDL cells, which in turn causes ankylosis upon replantation, followed by replacement resorption. Hank’s Balanced Salt Solution (HBSS) has been recommended as the standard storage medium for an avulsed tooth. Save-A-Tooth and EMT Tooth saver (Dentosafe)are commercially available tooth storage media. With the best of our knowledge no study has yet compared these media for their effective tooth storage times. The aim of this invitro study is to evaluate Save-A-Tooth, EMT Toothsaver (Dentosafe), and HBSS for their effect on …

Evaluation Of Die Trim Morphology Made By Cad/Cam Technology, Pratiksha Agrawal

Master's Theses (2009 -)

Purpose: The purpose of this vitro study was to evaluate the accuracy of the morphology of digitally trimmed dies in comparison with the subgingival contour of a prepared tooth to be restored with a single crown. Materials and Methods: 20 human extracted teeth, 10 incisors and 10 molars were disinfected, mounted on dentoforms. The teeth were prepared for a single all ceramic restoration. Digital impressions of the preparations were made using the 3M Lava COS. With the data, the SLA models were fabricated with removable dies. The prepared tooth and the corresponding dies were then compared with the Rhino software. …

Mitigating Distortion Of Light-Polymerized Composite Trial Bases, Jon Patrick Irelan

Master's Theses (2009 -)

Triad Visible Light Cure (VLC) Denture Base Material, a light-polymerizing resin material, is commonly used by clinicians to make trial bases during the fabrication of dentures and in planning the prosthetic and surgical rehabilitation of edentulous patients. A well-known drawback to this material, however, is its tendency to distort during the light-polymerization process. This distortion tends to occur most often towards the posterior aspect of the palate, and can negatively impact the bases ability to be retained through suction to the edentulous arch. The purpose of this study was to evaluate whether an experimental polymerization protocol can mitigate distortion during …

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 …

Effect Of Autoclaving On Flexibility Of Four Different Nickel Titanium Files, Anushree Mehrotra

Master's Theses (2009 -)

Introduction: Nickel-titanium (NiTi) files, introduced over 2 decades ago, have the unique property of superelasticity, are more resistant to fracture and are more flexible than stainless steel files. Recent developments in NiTi include M wire and Controlled/Thermal Memory Technology resulting in files with claimed superior properties to conventional NiTi files. Manufacturers recommend sterilization of files prior to usage. These files may be subjected to further autoclaving if reused. The purpose of this study was to test the effect of multiple cycles of autoclaving on the flexibility of four brands of NiTi files and to evaluate differences between brands. Materials and …

Effect Of Toothbrushing On Surface Roughness And Shade Of Extrinsically Stained Pressable Ceramic Restorations, Lessly Arlette Garza

Master's Theses (2009 -)

The purpose of this study was to investigate the effects of toothbrushing on surface roughness and shade change of extrinsically stained pressable ceramic restorations. Materials and Methods: Two materials, IPS Empress Esthetic and IPS e.max Press, were studied. For each material, 24 disc-shaped specimens, 10mm (diameter) x 3mm (height) were fabricated. Three different methods (n=8) of applying extrinsic stain was performed on each material: Glazed (G): glazed only (control); Stain then Glaze (SG): stained and fired, then glazed and fired. Stained and Glazed (T): glazed and stained together. Samples where brushed using a multi-station brushing machine. Each specimen was brushed …

Differential Scanning Calorimetric (Dsc) Study Of New And Sterilized Nickel-Titanium Rotary Endodontic Instruments, Michael Dyriw

Master's Theses (2009 -)

Introduction: Nickel-Titanium (NiTi) files have become popular in endodontic procedures compared to traditional stainless steel hand files owing to their increased flexibility which is especially advantageous in curved canals. Due to the associated costs, endodontic instruments are frequently re-used, which requires sterilization between uses. With the application of temperature NiTi has the ability to undergo phase transformations, altering the properties of the instruments. The purpose of this study was to investigate phase transformations of four brands of NiTi rotary endodontic instruments in the as-received condition and after multiple sterilization cycles under steam sterilization, using differential scanning calorimetry. Materials and Methods: …

Comparison Of Three Different Nickel-Titanium Endodontic Rotary Systems In Shaping Simulated S-Shaped Canals, Elineida Perez

Master's Theses (2009 -)

Introduction: Preparation error may result during mechanical instrumentation because of the complex anatomy of the root canal. Thus, flexibility and resistance to fracture are ideal properties that endodontic instruments should have. The aim of the study was to compare the shaping ability of three different nickel-titanium rotary instruments in simulated S-shape root canals by measuring transportation and canal volume change CVC. Materials and Methods: A total of 60 S-shaped canals in resin blocks were randomly allocated into 3 groups (n=20): Vortex Blue (Dentsply-Tulsa Dental Specialties), HyFlex CM (Coltène/Whaledent) and EndoSequence (Brasseler USA). Canals were filled with dye and secured in …

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 …

Accuracy And Precision Of Die Spacer Thickness With Combined Computer-Aided Design And 3-D Printing Technology, Lisa Hoang

Master's Theses (2009 -)

Purpose: The purpose of this study was to evaluate the accuracy and precision of die-spacer thickness achieved by the combination of computer aided design and 3-dimension printing technology.

Materials and Methods: An ivorine maxillary central incisor was prepared for an all ceramic crown. The prepared tooth was duplicated by using poly (vinyl siloxane) duplicating silicone and 80 die-stone models were produced using type IV dental stone. Dies were randomly divided into 5 groups with assigned die spacer thickness of (25 μm, 45 μm, 65 μm, 85 μm, 105 μm) (n=16/group). The printed resin copings, obtained from 3D Systems ProJet DP …

Influence Of Taper On The Flexibility Of Nickel-Titanium Rotary Files, Christopher J. Kingma

Master's Theses (2009 -)

Introduction: Modern nickel-titanium instruments have various tapers and have been marketed to have superior flexibility from previous generations. Current ISO standards require force measurements at a static point along the file. Unfortunately, root canal anatomy varies and produces multiple forces along the length of the file. The purpose of this study was to determine the influence of taper on the flexibility of various nickel-titanium files.

Materials and Methods: The flexibility of stainless steel hand files and nickel-titanium rotary files of various tapers was measured. The sample size was 10 for each type, taper and size. The files were measured at …

A Comparison Of Two Methods To Articulate A Maxillary Cast With Lateral Cephalometry, Laura H. Lux

Master's Theses (2009 -)

The Kois Dento-Facial Analyzer, an arbitrary articulation system, is used by clinicians to articulate and evaluate clinical cases. There is, however, limited information for understanding how the Kois Dento-Facial Analyzer should be utilized. Dr. Kois and Dr. Lee originally patented the device in 2003 yet there is essentially no evidence-based research in the literature. The purpose of this study was to evaluate the outcomes of articulating the maxillary cast using the Kois Dento-Facial Analyzer in three-dimensions as compared to the position of the cast when using Panadent’s Pana-Mount Facebow. Fifteen dried human skulls were used as test subjects. Maxillary diagnostic …

Evaluation Of Effect Of 17% Edta And 5.25% Sodium Hypochloride Irrigating Solutions On Surface Hardness Of Brasseler Endosequence Root Repair Material, Himanshu Sharma

Master's Theses (2009 -)

Introduction: Root Perforation is an artificial communication between the root canal system and supporting tissue. Various endodontic researchers have published that sealing the perforation immediately has the best prognosis but this predisposes the repair material to come in contact with various root canal irrigants during the course of treatment. The aim of this study was to evaluate the effect of 17% EDTA and 5.25% sodium hypochlorite irrigating solutions on surface hardness of Endosequence Root Repair Material Putty (ERRM).

Method: ERRM, 5.25% Sodium Hypochlorite, 17% EDTA and Deionized water were used. 42 samples were prepared and divided into 2 groups. Each …

Flexibility Of Various Nickel-Titanium Rotary Endodontic Files, Chelsea Selin

Master's Theses (2009 -)

Introduction: Nickel-titanium rotary files were originally developed to allow for greater flexibility when instrumenting root canals. The increased flexibility of nickel-titanium instruments allowed operators to negotiate canal curvatures with greater ease. File design is continually changing. Manufacturers are trying to produce files that will work more efficiently and safely. Knowing the properties of files marketed is especially important in helping to choose an appropriate file system. Current ISO standards require force measurements at a static point along the file. The purpose of this study was to evaluate the flexibility of four different nickel-titanium files at three different points along the …