Dental Materials Commons^™

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 …

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 …

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 …

Flexural Strength Of Nano-Hybrid Resin Composite As A Function Of Light Attenuation Distance And Specimen Dimension, Farid Sabry El-Askary Pro. Dr., Sara Adel Botros Dr., Mohamed Salah Abdelaziz Nassif Pro. Dr., Mutlu Özcan Prof. Dr.

Dentistry

This study evaluated ascending order of light attenuation distance (0, 2, 4, 8 mm) and specimen dimensions (2 × 2 × 10, 2 × 2 × 12, 2 × 2 × 15 mm3) differing from requirements of ISO 4049 (2 × 2 × 25 mm3) on the flexural strength of nano-hybrid resin composite. Specimens (N = 160) were prepared accordingly and randomly assigned into groups for the factors studied. Specimens were photo-polymerized from increased distances through 1, 2, 3 and 5 overlapping cycles depending on the specimen length after which they were subjected to three-point bending test (0.5 mm/min). …

Get In The Zone: A Survey Of Dental Professionals' Knowledge Of Ozone Therapy, Emily Hannah

Mahurin Honors College Capstone Experience/Thesis Projects

Ozone therapy has been used in medicine for many years to treat a variety of ailments. Ozone is an unstable triatomic molecule made up of three oxygen atoms. This molecule has the ability to kill bacteria, fungi, parasites, and viruses. The researcher first was curious if there has been research done on uses of Ozone Therapy in the dental setting. After reviewing the literature there is indeed a use for Ozone Therapy to treat a host of dental problems including periodontal disease, ulcers, and carious lesions (also known as cavities). However, there are conflicting conclusions in the literature as to …

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

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 …

Influence Of Low Temperature Degradation On Microstructural Integrity Of Zirconia Dental Implants, Mona Monzavi Rahimi

Loma Linda University Electronic Theses, Dissertations & Projects

Zirconia dental implants have become more popular in the field of implant dentistry. However, concerns have been raised regarding low temperature degradation and its influence on phase stability and micro-structural integrity in terms of increased micro-crack formation. In the case of dental implants, this could possibly result in delamination and interference with bone to implant contact and eventually lead to loss of integration and failure. Nevertheless, no study has reported the effects on commercially available Zirconia dental implants. The primary aims of this study was to determine if there is a correlation between ageing duration and 1) depth of tetragonal-monoclinic …

Influence Of Curing Protocol On Bond Strength Of Self-Etching Adhesives, Sara Adel Botros, Farid Sabry El-Askary, Mohamed Salah Nassef

Dentistry

No abstract provided.

Effect Of Light Distance Specimen Length On Flexural Strength Of Resin-Composite, Sara Adel Botros, Farid Sabry El-Askary, Mohamed Salah Nassef

Dentistry

No abstract provided.

Color Stability, Physical Properties And Antifungal Effects Of Zro2 And Tio2 Nanoparticle Additions To Pigmented Polydimethylsiloxanes, Mazen Alkahtany

Theses & Dissertations

Introduction: Color changes, physical degradation and fungal infections are potential challenges to the longevity of polydimethylsiloxane (PDMS) elastomers. The purpose of this study was to evaluate potential improvements in color change, physical properties and anti fungal properties of PDMS loaded with TiO2 and ZrO2 nanoparticles.

Methods: 1% weight of 40 nm or 200 nm diameter TiO2 or ZrO2 nanoparticles were mixed into PDMS with 2% functional intrinsic yellow pigment and polymerized. Control materials contained 13% weight 200 nm silica. Samples were exposed to either 3000 hours of UVB radiation (200 μW/cm2) or darkness. Color parameters L*a*b* and ΔE*, ultimate tensile …

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 …

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 …

Effects Of Microwave Irradiation On The Dimensional Stability Of Complete Denture Bases, Miguel Pappaterra

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Maintenance for complete dentures is a role that must be undertaken by the patient. It has been determined that two minutes of microwave irradiation at 650 Watts provides denture disinfection, and three minutes provide sterilization32,34. There is insufficient data on how this practice affects the long term dimensional stability of commonly used complete denture bases in the United States. Purpose: The purpose of this study was to perform an in-vitro investigation, testing and comparing the effects of microwave irradiation on the dimensional stability of three types of complete denture bases. Materials and Methods: An edentulous master cast with reference …

Libro De Actividades Por El Mes Nacional De La Salud Dental Infantil [Spanish Language Version: National Children's Dental Health Month Activity Book] (2016), American Dental Association Foundation

National Children's Dental Health Month

No abstract provided.

National Children's Dental Health Month Activity Book (2016), American Dental Association Foundation

National Children's Dental Health Month

No abstract provided.

Effect Of Polymerization Protocol On The Degree Of Conversion Of Photo- And Dual-Polymerized Self-Etch Adhesives, Lamiaa Mahmoud Moharam Dr., Sara Adel Botros Dr., Farid Sabry El-Askary Pro. Dr., Mutlu Özcan Prof. Dr.

Dentistry

This study investigated the effect of different polymerization protocols on the degree of conversion (DC%) of various photo-polymerized and dual-polymerized self-etch adhesive resins. Five different photo-polymerized (All-Bond Universal, Bisco; G-ænial Bond, GC; Futurabond M+ LC, VOCO; Single Bond Universal LC, 3M ESPE and Peak Universal Bond, Ultradent) and four dual-polymerized self-etch adhesives (Futurabond U, VOCO; Gradia Core SE, GC; Futurabond M+ DC, VOCO and Single Bond Universal DC, 3 M ESPE) were tested. All adhesives were applied on potassium bromide pellets (KBr) following the manufacturer’s instructions. The KBr pellets were divided into 10 experimental groups for the photo-polymerized adhesives and …

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, …