Open Access. Powered by Scholars. Published by Universities.®

Medicine and Health Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 7 of 7

Full-Text Articles in Medicine and Health Sciences

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 …


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 …


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 …


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 …


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 …


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 …