Dental Materials Commons^™

Effect Of Margin Thickness And Cement Gap On The Fabrication And Fit Accuracy Of Additively Manufactured Crowns In Definitive Resins With Different Filler Content, Mustafa Borga Dönmez, Gülce Çakmak, Çiğdem Kahveci, Amir H. Nejat, Burak Yilmaz, Pinar Altinci

School of Dentistry Faculty Publications

PURPOSE: To evaluate how commercially available composite resins in varying filler content affect the fabrication and fit accuracy (trueness and precision) of additively manufactured (AM) definitive crowns with different margin thickness and cement gaps by comparing them to subtractively manufactured (SM) polymer-infiltrated ceramic crowns. MATERIALS AND METHODS: Two identical unprepared mandibular right first molars were prepared by an experienced prosthodontist for crowns with either 0.5 mm or 1.0 mm chamfer margins, verified using silicone indexes and a periodontal probe, and then digitized with an industrial-grade scanner. These scan files were used to design reference crowns with either 50-µm or 80-µm …

From Molars To Bronchus; The Tale Of An Aspirated Dental Instrument, Yisroel Grabie, Sudeep Acharya, Fasih Sami Siddiqui, Gabriel A. Chavez Reyna, Michel Chalhoub

HCA Healthcare Journal of Medicine

Background

Aspiration of dental instruments is a rare event that carries potentially serious complications when it occurs, especially in older patients, where protective reflexes are diminished. Clinical management may be difficult because of the risk of granulation tissue and different retrieval strategies according to the object’s characteristics. In this report, we describe the case of an 84-year-old man who aspirated a dental bur during a routine dental procedure, necessitating immediate intervention. Timely and precise management was essential to avert severe complications.

Case Presentation

During a routine dental procedure, an 84-year-old man aspirated a bud-shaped cross-cut carbide dental bur. Despite initial …

The Effect Of Different Surface Treatments On The Roughness, Translucency, And Staining Of 3d-Printed Occlusal Device Materials, Silvia Rojas Rueda, Hanna Sepsick, Mohammed Hammamy, Amir H. Nejat, Edwin Kee, Nathaniel C. Lawson

School of Dentistry Faculty Publications

OBJECTIVES: To compare surface treatments (as-printed, optical polish, resin-coated, polished) of two 3D-printed occlusal device materials (KeySplint Soft and NightGuard Flex 2) cured with or without glycerin for surface roughness, translucency, and coffee staining. MATERIALS AND METHODS: Discs (2 mm thick) from two 3D-printed occlusal resins (KeySplint Soft and NightGuard Flex 2) were printed using a DLP 3D printer (SprintRay Pro 95), cleaned (ProWash S), and cured (ProCure 2) with or without glycerin. Some specimens were printed in an optical polish tank. Specimens were either as-printed, resin-coated, or polished. Reference milled (ProArt CAD Splint) and heat-cured (Excel Formula Heat Cure …

Endodontic Microsurgery Using Dynamic Navigation And Trephine Burs, Trenton Smith, Sameer Jain, Jeffery Nick Sanders, Michael Block, Mark Odom, Albert F. Mcmullen

School of Dentistry Faculty Publications

Objectives: The use of the surgical operating microscope, CBCT imagining, biocompatible filling materials and ultrasonic instruments have improved the success and predictability of apical surgery. Despite these advances, more accurate and precise techniques for creating osteotomies and root-resections (apicoectomies) have not been widely adopted. This study highlights how dynamic navigation systems (DNS) can help avoid unnecessary dentin removal and “mitigate iatrogenic errors” such as root perforation. Methods: A total of 56 root-end resections were planned and completed on two sets of identical TrueJaw Endosurg models (DE Labs, Santa Barbra, CA, USA). One set of maxillary and mandibular jaws were used …

J Mich Dent Assoc August 2021

The Journal of the Michigan Dental Association

Every month, The Journal of the Michigan Dental Association brings news, information, and features about Michigan dentistry to our state's oral health community and the MDA's 6,200+ members. No publication reaches more Michigan dentists!

In this issue, the reader will find the following original content:

• A cover story on “Diversity, Equity, Inclusion, and Dentistry: Understanding the MDA’s Perspective”.
• A feature article, “Diversity, Equity, Inclusion, and Dentistry: Its Impact on Oral Health — You Can Make a Difference!”.
• A feature article from the Journal’s DEI series, “Welcoming Diversity, Equity, and Inclusion with Students Considering Careers in Dentistry”.
• A feature clinical article …

Maintaining Root Canal Curvatures After Preparation With Different Nickel-Titanium Rotary Systems (A Comparative In Vitro Study), Wael Betbout, Mohammad Al Shammaa, Roula S. Abiad

BAU Journal - Creative Sustainable Development

The ongoing advancement of materials and methods for root canal instrumentation is resulting in improved techniques with minimal variations to the canal morphology. One standard for assessment of the shaping quality of curved root canals is preparation-induced straightening of the canal. The aim of the study: To compare the effects of 2 Nickel-Titanium rotary systems, 2Shape (Micro-Mega, Besançon, France) and ProTaper Next (Dentsply,Sirona, Ballaigues, Switzerland), on maintaining the distobuccal canals curvature of extracted human maxillary molar teeth using periapical radiographs. Materials and methods: In this study a total of 26 distobuccal roots of upper maxillary molars were used and divided …

Oral Wellness: Using Occupational Therapy To Enhance Oral Hygiene Delivery In Long-Term Care, Lauryn J. Banovitz, Liberty Bellah, Rosemarie Lion

Dissertations, Masters Theses, Capstones, and Culminating Projects

Based on current literature, oral health in long-term care (LTC) facilities is frequently of low priority and does not follow evidence-based best practices. Poor oral health reduces the quality of life of older adult residents and patients and can lead to systemic diseases, such as cardiovascular disease, stroke, and pneumonia, the leading cause of death in LTC. Occupational therapists can play an instrumental role as oral care consultants, and educators, and can act as resource guides to raise the standards of oral care in LTC facilities.

This capstone project explored ways in which occupational therapy, a profession traditionally designated for …

Micromechanical Analysis Of Nanoparticle-Reinforced Dental Composites, Yi Hua, Linxia Gu, Hidehiko Watanabe

Department of Mechanical and Materials Engineering: Faculty Publications

The mechanical behavior of TiO₂ nanoparticle-reinforced resin-based dental composites was characterized in this work using a three-dimensional nanoscale representative volume element. The impacts of nanoparticle volume fraction, aspect ratio, stiffness, and interphase zone between the resin matrix and nanoparticle on the bulk properties of the composite were characterized. Results clearly demonstrated the mechanical advantage of nanocomposites in comparison to microfiber-reinforced composites. The bulk response of the nanocomposite could be further enhanced with the increased nanoparticle volume fraction, or aspect ratio, while the influence of nanoparticle stiffness was minimal. The effective Young’s modulus and yield strength of the composite was …

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 …

Comparison Of Microleakage In Three Sealant Placement Protocols Vs. The Enamel Loc System, Audrey T. Sheu

Loma Linda University Electronic Theses, Dissertations & Projects

PURPOSE: To evaluate sealant microleakage using four different application techniques.

METHODS: The four application techniques evaluated were acid etch only, Adper L-Pop bonding, Optibond bonding, and Enamel Loc One-Step Sealant. Sixty-four extracted third molar teeth were assigned on one of four application techniques (n=16) and Clinpro sealants applied according to the manufacturer's instructions. The teeth were thermocycled for 500 cycles, dyed, and embedded in resin. The samples were then sectioned and evaluated for microleakage on the buccal and lingual surfaces. Statistical methods employed to analyze the data were the Kruskal-Willis rank test and the Mann-Whitney U test.

RESULTS: No significant …

Immediate Provionalization Of Single Threaded Oxidized Implants On Maxillary Premolars Healed Sites: One-Year Study, Kiyotaka Umezu

Loma Linda University Electronic Theses, Dissertations & Projects

Osseointegrated endosseous implants have been widely used and become a predictable treatment option for completely and partially edentulous patients. The viability and predictability of this treatment modality have been supported with the high success rates in numerous studies. Clinical guideline requires a healing period of 3 to 6 months without functional loading to achieve osseointegration with machine surface implants. Therefore, numerous studies on immediately loaded implants have been conducted in an attempt to minimize or eliminate this healing period. The purpose of this study was to evaluate the success rate of the immediately provisionalized oxidized-surface implants in healed sites supporting …

Comparison Of Laser And Phosphoric Acid Etching On Sealant Shear Bond Strength, Seth David Latimer

Loma Linda University Electronic Theses, Dissertations & Projects

PURPOSE: To compare the effect of traditional phosphoric acid etching with Er,Cr:YSGG laser enamel etching on the shear bond strength of sealant material.

METHODS: Extracted healthy third molars were mounted in acrylic exposing the flattest surface available. Three groups of twenty teeth were used to evaluate traditional acid etching with 37% phosphoric acid as a control group as well as two different laser settings. The sealant material was attached using specialized jigs and then subjected to shear bond strength testing utilizing the ultradent method (MTS machine). Statistical methods employed were the Kruskal-Wallis rank test and the Mann-Whitney U test.

RESULTS: …

Bone Morphogenic Protein Induced Repair Of The Premaxillary Cleft, Rick J. Rawson

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study is to evaluate the bony augmentation of premaxillary clefts in humans using recombinant bone morphogenic protein (rhBMP-2) in a collagen sponge carrier. 12 patients with unilateral cleft alveolar ridges were evaluated pre- and 4 months postoperatively. 10 patients were repaired with rhBMP-2 while two others were grafted with anterior iliac crest particulate marrow cancellous bone (PMCB). Computed tomographic studies were used to evaluate preoperative alveolar cleft volumes, postoperative bone bridge volumes, and pre/post operative volume ratios.

A pre/post operative volume ratio for patients repaired with rhBMP-2 ranged from 24.1% to 90.6% with a mean of …

De-Bonding 4 Brands Of Ceramic Brackets With The Waterlase Er,Cr;Ysgg Laser, Carter A. Lane

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine if the Biolase Waterlase Er,Cr:YSGG laser could be used as a safe and effective tool to de-bond four currently available orthodontic ceramic brackets. Changes in interpulpal temperature, enamel surface conditions and the amount of time the laser was activated to debond (sic) the ceramic brackets were evaluated. Forty human maxillary premolars were divided into four groups of ten. Prior to direct bonding, all extracted teeth were impressed and duplicated in Araldite epoxy resin as the control surface. Identical techniques were used to bond 10 ceramic brackets from each manufacturer. Three of the …

Resonance Frequency Analysis As A Determinant Of Implant Initial Stability, Negar Tabandeh

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: The clinicians' decision regarding immediate loading is largely determined by the assessment of initial stability of the dental implant. Computed tomographic assessment of recipient site bone quality, insertion resistance torque and post-insertion resonance frequency are currently the only objective methods of measurement establishing initial stability.

Purpose: A study was designed to measure resonance frequency of root form dental implants placed in cadaver jaws. The resonance frequency values were compared to previous subjective and objective data reported in prior studies in the series.

Materials and Methods: Resonance frequency measurements were secured using the Osstell ™ mentor unit on 4.0 X …

Comparison Of Bracket Bond Strength By Total, Self-Etch And Laser Treatment, Kyo Sung Shawn Kim

Loma Linda University Electronic Theses, Dissertations & Projects

Laser etching of enamel surfaces alters the physical and chemical characteristics of the enamel. These changes in characteristics enhance the bonding to enamel. The purpose of this study was to compare the shear and tensile bond strength of Er,Cr:YSGG hydrokinetic laser system (Biolase) with 37% phosphoric acid and self etching primer 30 minutes and 72 hours after bonding. Four different laser power output setting was observed: 1.5W, 2.0W, 2.5W, and 3.0W. Two hundred forty bovine teeth free of defect, caries, and dentin exposure were mounted in acrylic resin and divided into 24 groups of 10 teeth. Sixteen groups of 10 …

The Radiopacity Of 29 Resin Restorative Materials Compared To Enamel, Peter Lubisich Iv

Loma Linda University Electronic Theses, Dissertations & Projects

The radiodensity of a composite resin can greatly influence a clinician's ability to analyze a restoration for failure. The purpose of this study was to determine the relative radiopacities of 29 resin restorative materials compared to enamel, and to verify the comparable radiopacity between shades of 23 of the restorative composite resin materials. Composite resin discs measuring >5mm in diameter and 2 mm in thickness were made and polymerized. Radiographs were taken of the composite resin discs, which included an aluminum step wedge for calibration and a densitometer was used to measure the radiodensity of the composite resin samples. The …

Effects Of Mtad On Some Physical Properties Of Enamel And Dentin, Tanya Kristina Machnick

Loma Linda University Electronic Theses, Dissertations & Projects

Recently, a Mixture of Tetracycline, an Acid, and a Detergent (MTAD) has been advocated to remove smear layer and disinfect canals. The purpose of this study was to evaluate the effect of MTAD the flexural strength and modulus of elasticity of dentin as well as its effect on the bond strength to enamel and dentin. In Part I, dentin bars were randomly assigned to eight groups treated either with various concentrations of NaOCl (5.25%, 2.65%, 1.31%, 0.66%), 17% EDTA, MTAD, saline, or according to a clinical protocol with 1.3% NaOCl and then 5 min of MTAD. …

Bond Strengths Of Three Orthodontic Adhesives For Direct And Indirect Bonding, Aaron Rondon

Loma Linda University Electronic Theses, Dissertations & Projects

The technique of bonding orthodontic brackets utilizing a transfer tray, otherwise known as indirect bonding, is a dichotomous subject. It allows for more accurate bracket placement and reduced chair time for the patient and doctor, yet its technique sensitivity can yield bracket failures at the time of tray removal. With the recent development of 3M's Sondhi Rapid Set, an adhesive specifically designed for orthodontic bonding, the purpose of this study was to compare this fairly new indirect adhesive with 3M's Transbond XT and Reliance's Rely-A-Bond.

Two hundred and seventy freshly extracted bovine teeth were mounted in acrylic resin and divided …

Patient Satisfaction And Effectiveness Of A New Resin Used To Bumper Orthodontic Brackets, Timothy B. Elison

Loma Linda University Electronic Theses, Dissertations & Projects

Fear of pain is a key factor in discouraging patients from seeking orthodontic treatment, with many patients discontinuing treatment due to pain experienced in the early stages of treatment. Patients often complain of traumatized lips and buccal mucosa, which is usually caused by the brackets. Orthodontists try to minimize this pain and discomfort by using bumpering materials. Although wax is the most commonly used product, there are many bracket bumpering materials available.

The purpose of this study was to evaluate the clinical effectiveness and patient comfort/satisfaction of a new flowable resin, Ortho Shield, designed to protect the lips and …

Fracture Properties Of Different Orthodontic Bonding Materials, Daryl Lynden Proctor

Loma Linda University Electronic Theses, Dissertations & Projects

Spontaneous debonding has proven a constant problem since the introduction of bonded orthodontic brackets in the early 1960's by Newman¹.

Components in classic bond strength testing are the bracket, the adhesive, the adhesive curing method, the type of teeth used, and the test method. These tests lead to extensive and compounding variables that make it difficult to evaluate the performance of any of the components individually.

The purpose of this study was to compare several contemporary orthodontic bonding adhesives by testing the physical and mechanical characteristics of the adhesives alone. Material properties compared were sonic and tensile measurements …

Failure Mode Of An Orthodontic Resin Alone And With Bonded Brackets, Marc Cody Dunn

Loma Linda University Electronic Theses, Dissertations & Projects

Since the introduction of bonded orthodontic brackets in the early 1960's spontaneous debonding has been a constant nemesis. Most attempts to avoid this problem by orthodontic manufactures have focused on "bond strength" issue. Whether they chose to address the materials, the bracket base or both, the common method used to evaluate improvements entailed the use of just one testing apparatus: a static universal testing machine such as the Instron.

Metal, ceramic and plastic bonded brackets were tested with the traditional shear/peel method as well as a new high strain rate impact test. The resin itself was also evaluated for physical …

Clinical Debonding Simulation Study Of One Metal And Two Ceramic Brackets, Hyunsup Shim

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study is to compare two mechanical debonding methods on ceramic brackets (TP MXi and 3M Clarity) and a metal bracket (GAC OmniArch) with four different bonding materials (light-cured, one-step chemical-cured, two-step chemical-cured, and Fuji GIC) in clinical simulation, where the diametral force was applied on the handle of the pliers. The effectiveness of mechanical debonding technique was determined by evaluating the following variables: the amount of force required to debond the bracket, the amount of residual adhesive remaining on the enamel surface, the frequency of unexpected bracket failure, and the prevalence of visible enamel damage. The …

Mutagenecity Of Formocresol, Glutaraldehyde, Ferric Sulfate And Aluminum Chloride : Materials Used In Therapeutic Pulpotomies, Adolfo Barrera

Loma Linda University Electronic Theses, Dissertations & Projects

Ferric sulfate (Astringedent) and aluminum chloride (Hemodent) have been proposed as possible medicaments for use in primary teeth for therapeutic pulpotomies.

There is little information in the literature about the biologic properties of these medicaments.

The purpose of this study was to evaluate the mutagenic response of the ferric sulfate and aluminum chloride and compare them with glutaraldehyde (1.5%, 1% and 0.5% concentration) and formocresol (2%, 0.75%, 0.01% and 0.005% concentration). TA98 and TA1535 strain were used in the Ames test to assess mutagenecity. Neither ferric sulfate nor aluminum chloride exhibited mutagenic potential, in comparison with glutaraldehyde and formocresol, which …

The Effects Of Rapid Palatal Expansion Therapy On The Periodontal Tissues Of The Central Incisors, Richard Gutierrez

Loma Linda University Electronic Theses, Dissertations & Projects

The periodontal structures around the maxillary central incisors in thirty-nine post-orthodontically treated patients, twenty-five of these patients had experienced Rapid Palatal Expansion (RPE), were examined to determine the periodontal consequences associated with two ways of managing the resultant diastema. In fourteen patients the diastema closure was assisted by elastomeric chain and in eleven patients the diastema closure was not assisted. Fourteen non-RPE orthodontically treated patients served as controls. Height of attached gingiva, gingival sulcus depth, attachment level, and alveolar bone level were recorded. One examiner, using calibrated techniques, performed all the measurements. The RPE groups and the control group all …

A Pilot Study Comparing The Forces Applied : Using A Chin Cup And Three Types Of Protraction Headgear, Daniel Miles Beisiegel

Loma Linda University Electronic Theses, Dissertations & Projects

A pilot study comparing force distributions of a chin cup, the Great Lakes reverse pull headgear (RPHG), Ormco's adjustable dynamic RPHG, and Grummons RPHG was done. A skull from a 69 year old female which demonstrated a Class III malocclusion was used to perform the tests of force. Forces applied to and generated on the skull were measured using a water-filled balloon system. This method was tested and found to be reliable and accurate.

Repeated measurements of force were recorded for each of the areas of stress (forehead, cheeks, chin, and condyles, as well as the posterior and superior portions …

An In Vitro Quantitative Evaluation And Comparison Of A Custom And A Popular Stock Orthodontic Appliance, Richard Scott Anderw Schalo

Loma Linda University Electronic Theses, Dissertations & Projects

An in vitro performance evaluation and comparison of a patient individualized appliance (Elan, Ormco Corporation, Glendora, California) and a Roth prescription appliance ("A"- Company, San Diego, California) was made using the Ideal Tooth Relationship Index (ITRI).

The sample consisted of 19 duplicated sets of models for a total sample of 38. For each pair of models one set was bonded with an Elan appliance and a duplicated set was bonded with a Roth appliance. Bracket placement followed the manufacturers recommendations. The bracketed teeth from these models were sectioned out individually and the appliances allowed to fully express themselves on full …

Load Deformation Test Of Mini Twin Metal Brackets : A Comparative Study, Karl D. Peach

Loma Linda University Electronic Theses, Dissertations & Projects

The trend toward more esthetic brackets has led to smaller brackets being used by orthodontists. The purpose of this study was to determine the force required to deform these smaller brackets and calculate the stress in the metal by using a torsional wire bending force. Ten types of brackets were tested and the results analyzed to determine how bracket geometry, manufacturing method, or material selection affected the strength of brackets. Results showed a significant difference between manufacturing methods, material used, and bracket geometry. Brackets made of 17-4 PH SS and 303 SS withstood higher stress than 316 SS, and all …

An In Vitro Evaluation Of Commercially Available Disposable Prophylaxis Angles, Caren M. Barnes, Lisa S. Fleming, Carl M. Russell

College of Dentistry: Faculty Publications

Although a number of manufacturers are marketing disposable prophylaxis angles, no literature exists regarding the mechanical efficacy and efficiency of these products. It was the purpose of this in vitro evaluation to compare and evaluate five brands of commercially available disposable prophylaxis angles for vibration, noise, heat rise, and torque. Random samples of each brand of disposable prophylaxis angle were utilized. Vibration was measured with a height gauge and running motor; noise was measured with a sound meter and heat rise was measured from 68°F on the head and body of the disposable prophylaxis angles, and torque required to destroy …

An In Vivo Comparison Of Commercially Available Disposable Prophylaxis Angles, Lisa S. Fleming, Caren M. Barnes, Carl M. Russell

College of Dentistry: Faculty Publications

A wide variety of disposable infection control products is being marketed including disposable prophylaxis angles. It was the purpose of this in vivo investigation to evaluate the clinical efficacy of five different brands of commercially available disposable prophylaxis angles. Utilizing a splitmouth design. 11 dental hygienists evaluated disposable prophylaxis angles while completing a routine oral prophylaxis. Fifty samples each of Brahler. Ash/Dentsply, Denticator. and Young Dental angles were compared to a control angle (Teledyne Getz). A questionnaire was completed by each operator following patient treatment (a total of 161 patients was treated). The questionnaire asked questions in which the four …