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Full-Text Articles in Dentistry

The Effect Of Heat Treatment On The Bending Properties Of A Cobalt-Chromium Orthodontic Wire, Alex Schwab Jul 2017

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 …


Reliability Of Digital Dental Cast Measures As Compared To Cone-Beam Computed Tomography For Analyzing The Transverse Dimension, Brian Michel Jul 2017

Reliability Of Digital Dental Cast Measures As Compared To Cone-Beam Computed Tomography For Analyzing The Transverse Dimension, Brian Michel

Master's Theses (2009 -)

The purpose of this study was to assess the consistency in diagnosing the transverse dimension on cone-beam computed tomography (CBCT) images as compared to digital dental models. The study consisted of 11 patients with posterior crossbite at the level of the first molar and 17 patients with no crossbite at the level of the first molar. 13 patients were male and 15 patients were female with an overall mean age of 13.6 years. Eight linear measurements and two angular measurements were made on CBCT images of the patients and six linear measurements were made on the corresponding digital dental casts. …


Thermal Properties Of Commonly Used Clear Aligner Systems As-Received And After Clinical Use, Louis Wenger Jul 2017

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 …


Direct Visual Approximation Of Arch Length Discrepancy And Cephalometric Measurements, Bradley J. Wurm Jul 2017

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 …


Viability Of Human Periodontal Ligament Fibroblasts After Time In Tooth Storage Media, Scott Macdonald Apr 2017

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 …


Survival Rates Of Primary Endodontic Therapy Following Core/Post And Crown Placement, Kandace Yee Apr 2017

Survival Rates Of Primary Endodontic Therapy Following Core/Post And Crown Placement, Kandace Yee

Master's Theses (2009 -)

Introduction: The objective of this study was to determine if a correlation exists between the time to core or post and core (core/post) placement following non-surgical root canal therapy (NS RCT), the time to crown placement following core/post placement, and the incidence of an untoward event. Materials and Methods: Utilizing the Delta Dental of Wisconsin Insurance Database, information was analyzed from 476,479 initial NS RCT procedures. Of these teeth, 160,040 had a core/post and a crown placed before the end of the continuous coverage period or occurrence of an untoward event. Untoward events were defined as having a retreatment, apicoectomy, …


Qmix 2in1 And Naoci Precipitate: Documentation, Identification, And Exothermic Reaction, Gordon L. Barkley Iii Apr 2017

Qmix 2in1 And Naoci Precipitate: Documentation, Identification, And Exothermic Reaction, Gordon L. Barkley Iii

Master's Theses (2009 -)

Introduction: The aim of this study was to document and identify precipitate formation and exothermic reaction caused when mixing NaOCl and QMiX. Methods: Photography captured time-dependent changes when mixing NaOCl and QMiX at; 0 seconds, 30 seconds, 1 minute, 30 minutes, 1 hour, and 24 hours. A differential scanning calorimeter (DSC) was utilized in determination of heat flow while analyzing temperature change (°C), enthalpy (mJ), and time (seconds) for NaOCl with QMiX and NaOCl with 2% chlorhexidine (CHX). 1H Nuclear Magnetic Resonance (NMR) and 2D NMR (DOSY) spectroscopy analyzed precipitation formed from NaOCl and QMiX. Results: Digital photography documented immediate, …


Analysis Of Flexural Strength And Monotonic Load To Failure Following Simulated Chairside Adjustments And Repair In A Lithium Disilicate Glass-Ceramic, Ali Ramadhan Apr 2017

Analysis Of Flexural Strength And Monotonic Load To Failure Following Simulated Chairside Adjustments And Repair In A Lithium Disilicate Glass-Ceramic, Ali Ramadhan

Master's Theses (2009 -)

Introduction: There are no studies regarding e.max Press that evaluate post-adjustment healing protocols and their effect on the load to failure in a clinically relevant test. It is essential to find the ultimate treatment protocol which will help clinicians preserve the physical properties of the ceramic restoration after adjustment. Material and Methods: The total number of samples used in this study was 440 IPS e.max press discs. The discs were 15 mm in diameter and 1 mm of thickness. The material was tested for flexural strength and monotonic load to failure. The test was done in two parts and with …


Comparison Of Anterior Denture Teeth Arrangements Made With The Tooth Mold Template And Definitive Computer-Aided Design & Computer-Aided Manufacturing Complete Removable Dental Prostheses, Jose Antonio Sierra Apr 2017

Comparison Of Anterior Denture Teeth Arrangements Made With The Tooth Mold Template And Definitive Computer-Aided Design & Computer-Aided Manufacturing Complete Removable Dental Prostheses, Jose Antonio Sierra

Master's Theses (2009 -)

Introduction: There is a dearth of information in the refereed literature regarding esthetics of CAD/CAM complete removable dental prostheses (CRDPs). The purpose of this study was to investigate and compare the anterior denture teeth arrangement made with the medium-size anterior tooth mold template to CAD/CAM complete removable dental prostheses fabricated with bonded denture teeth and milled teeth. Material and methods: Poly-vinyl siloxane impression were made of an edentulous maxillary model and selected for use as the patient template. The edentulous model was mounted on a semi-adjustable articulator. Definitive impressions and jaw relation records were made according to the manufacturer’s protocol. …


Color Change Of Commercial Resin Composited With Different Photoinitiators, Feng Gao Oct 2016

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 …


Thermal Properties Of Copper Nickel-Titanium Orthodontic Archwires, Joshua Gilbert Jul 2016

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 …


Mechanical Properties Of Copper-Nickel-Titanium Archwires, Margaret Amelia Rosen Jul 2016

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 …


The Effect Of Orthodontic Appliances On The Evaluation Of The Professionalism And Esthetics Of An Adult Employee, Laura Hanson Vaccariello Jul 2016

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 …


The Effects Of Mechanical Vibration On Human Chondrocytes In Vitro, Bradley J. Gauthier Jul 2016

The Effects Of Mechanical Vibration On Human Chondrocytes In Vitro, Bradley J. Gauthier

Master's Theses (2009 -)

Introduction: Inflammation is the biological basis of temporomandibular joint disorders (TMD), when severe it can lead to osteoarthritis. One of the physical therapies used to manage this condition is mechanical vibration, as has been used in medicine for many years as a non-pharmacological therapy. Recently an FDA approved dental device called AcceleDent has been introduced to increase the rate of tooth movement and decrease pain. As the device-generated vibration transmits to the TMJ, it is important for us to investigate whether mechanical vibration influences TMJ on its biologic basis – chondrocytes under normal and inflammatory conditions. Materials and Methods: Human …


The Effect Of Mechanical Vibration On Human Pdl Cell Differentiation And Response To Inflammation, Megan Desroches Jul 2016

The Effect Of Mechanical Vibration On Human Pdl Cell Differentiation And Response To Inflammation, Megan Desroches

Master's Theses (2009 -)

Low magnitude mechanical vibration is a therapeutic adjunct being investigated to alter bone remodeling and inflammation in areas such as osteoporosis, bone fracture healing, and muscle soreness after exercise. In orthodontics a device named AcceleDent has been marketed that claims to increase the rate of tooth movement and decrease pain. However evidence for these claims is lacking. In this study we looked at two potential cellular mechanisms for these claims: periodontal ligament (PDL) cell differentiation and inflammation under an orthodontic model of strain (IL-1β). Increased PDL cell differentiation into osteogenic cells could be an avenue of increasing orthodontic tooth movement. …


Evaluation Of Die Trim Morphology Made By Cad/Cam Technology, Pratiksha Agrawal Apr 2016

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 Apr 2016

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 …


Torsion And Bending Properties Of Edgeendo Files, Chad Hansen Apr 2016

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 …


Outcomes Of Primary Endodontic Therapy Provided By Endodontic Specialists Compared To Other Providers, Jacob Burry Apr 2016

Outcomes Of Primary Endodontic Therapy Provided By Endodontic Specialists Compared To Other Providers, Jacob Burry

Master's Theses (2009 -)

Introduction: The objective of this study was to compare the outcomes of initial non-surgical root canal therapy (NSRCT) for different tooth types provided by both endodontists and other providers. Methods: Using an insurance company database, 487,476 initial NSRCT procedures were followed from the time of treatment to the presence of an untoward event indicated by Current Dental Terminology (CDT) codes for retreatment, apical surgery, or extraction. Population demographics were computed for provider type and tooth location. Kaplan-Meier survival estimates were calculated for 1, 5, and 10 years. Hazard ratios for provider type and tooth location were calculated using the Cox …


Viability Of Human Periodontal Ligament Fibroblasts After Storage In Save-A-Tooth, Emt Toothsaver And Hank's Balanced Salt Solution, Wonhee Lee Apr 2016

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 …


Changes In Composite Toxicity Following Exposure To Pulp Capping Materials, Audra Long Jul 2015

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, …


The Direct Effect Of Low-Magnitude High-Frequency Mechanical Vibration On Osteoclast Formation From Raw267.4 Monocytes, Maxwell Antonio Abraham Jul 2015

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 Jul 2015

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 …


Influence Of Fluoride And Stress On The Mechanical Properties Of Nickel-Titanium Coils, Jennifer Ann Fehrman Roloff Jul 2015

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 …


Mechanical Properties And Patient Perceptions Of Commonly Used Clear Aligner Systems As-Received And After Clinical Use, Lauren Evan Montoure Teske Jul 2015

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 …


Thermomechanical Characterization Of Variable Force Niti Orthodontic Archwires, Anjali Sudershan Krishan Mehta Jul 2015

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 …


Comparison Of Three Different Nickel-Titanium Endodontic Rotary Systems In Shaping Simulated S-Shaped Canals, Elineida Perez Apr 2015

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 …


Effect Of Toothbrushing On Surface Roughness And Shade Of Extrinsically Stained Pressable Ceramic Restorations, Lessly Arlette Garza Apr 2015

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 …


Effect Of Autoclaving On Flexibility Of Four Different Nickel Titanium Files, Anushree Mehrotra Apr 2015

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 …


Differential Scanning Calorimetric (Dsc) Study Of New And Sterilized Nickel-Titanium Rotary Endodontic Instruments, Michael Dyriw Apr 2015

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: …