Dentistry Commons^™

In Vitro Comparison Of Force Decay Between Three Orthodontic Sliding Retraction Methods, Pamela Steiger

Student Theses, Dissertations and Capstones

Objective: The purpose of this in vitro study was to determine if there is a difference in force decay between three sliding retraction methods under a standardized force delivery system (200 gm at 25 mm stretch) at 2, 4, 6, and 8 weeks. Background: In order to achieve proper esthetics, occlusion and stability, orthodontic treatment may require extractions. Elastomeric chains, Nickel Titanium (NiTi) coils, and active ligatures are commonly used to close these extraction spaces. Methods: Twenty samples of each retraction method (elastomeric chains, NiTi Coils and active ligatures) were evaluated under standardized conditions (200 gm at 25 mm). The …

Cephalometric Regional Superimpositions -- Digital Vs. Analog Accuracy And Precision : 3. The Cranial Base, Douglas Shaw

Student Theses, Dissertations and Capstones

Objective. To assess the accuracy and precision in measurement of pairwise implant displacement across three methods of cranial base superimposition. Background. Cephalometric superimposition is the principal radiographic method used to evaluate changes within the craniofacial skeleton. Many studies have examined the accuracy of software intended to produce cephalometric superimposition. Such studies have utilized anatomic landmarks, selected by the respective software manufacturers, as registration points for constructing superimpositions and their analysis. As a result, these studies are only as accurate as the stability and validity of anatomic registration landmarks used. To our knowledge, no other study has utilized metallic implants to …

Effect Of Cad/Cam Processing On Esthetic Characteristics Of Porcelain Veneers, Eduardo Cortes-Contreras

Student Theses, Dissertations and Capstones

Introduction: Dentistry has changed significantly during the last two decades. Patients are more aware and demanding of the latest technologies available in restorative dentistry. The purpose of this study was to determine any possible changes on the surface roughness, gloss and color change of CAD-CAM milled porcelain veneers following repeated milling times, before and after a glazing process. Methods: A Teflon disk-shaped mold was used as a cast to take a digital impression (BlueCam) in order to fabricate cylindrical-shaped specimens. A total of one hundred (N=100) specimens porcelain veneers using Empress CAD (I10) block, were milled using the CAD/CAM CEREC-SIRONA …

Evaluation Of The Effect Of Enamel Deproteinization On Shear Bond Strength Of Orthodontic Adhesives And Resulting White Spot Lesion Formation, Kelly Chioffe

Student Theses, Dissertations and Capstones

A thesis submitted to the College of Dental Medicine of Nova Southeastern University of the degree of Master of Science in Dentistry.

Objective: The objectives of this study were 1) to evaluate the effect of enamel deproteinization on the shear bond strength(SBS) of orthodontic brackets bonded with a resin modified glass-ionomer (RMGI) adhesive and a composite resin, 2) to determine the mode of bond failure according to the adhesive remnant index (ARI) and 3) to evaluate the effect of these adhesives in the prevention of white spot lesions (WSLs). Background: WSLs are a concern for orthodontic patients. RMGI orthodontic adhesives …

Bmp2 Induced Osteogenic Differentiation Of Human Umbilical Cord Stem Cells In A Peptide-Based Hydrogel Scaffold, Shruthi Lakshmana

Student Theses, Dissertations and Capstones

Craniofacial tissue loss due to traumatic injuries and congenital defects is a major clinical problem around the world. Cleft palate is the second most common congenital malformation in the United States occurring with an incidence of 1 in 700. Some of the problems associated with this defect are feeding difficulties, speech abnormalities and dentofacial anomalies. Current treatment protocol offers repeated surgeries with extended healing time. Our long-term goal is to regenerate bone in the palatal region using tissue-engineering approaches. Bone tissue engineering utilizes osteogenic cells, osteoconductive scaffolds and osteoinductive signals. Mesenchymal stem cells derived from human umbilical cord (HUMSCs) are …

Influence Of Immediate Dentin Sealing On The Bond Strength Of Indirect Bonded Restorations, Alexander Duque

Student Theses, Dissertations and Capstones

Introduction: A critical issue and concern that has been documented in dentistry is the complexity of bonding to dentin, a fact that has been referred to as a less reliable technique due to the intrinsic characteristics of the dentin substrate. Effectiveness on dentin bonding is a clinical important approach for indirect bonded restorations in order to achieve a good adhesion that can surpass the test of time. Long-term clinical trials have shown that indirect bonded restorations have an increased risk of failure when using dentin as the major substrate. Consequently, an effort should be made to improve techniques and materials …

Cephalometric Regional Superimpositions -- Digital Vs. Analog Accuracy And Precision : 1. The Maxilla, Glenn Krieger

Student Theses, Dissertations and Capstones

Introduction: The purpose of this study was to measure the displacement of defined dental structures, as a result of superimposition of cephalometric images across paired time-points by both digital and analog methods. The magnitudes of such displacements across three methods of superimposition were compared to each other and to a reference method constructed by registering superimposed cephalometric images on tantalum markers implanted in the study participants' maxillae. The defined dental structures were: 1) First molar mesial contact point; 2) First molar apical root bisection; 3) Central incisor root apex; 4) Central incisor crown incisal edge. Methods: Lateral cephalograms of 22 …

Effect Of Resin Cement, Aging Process And Root Level On The Bond Strength Of The Resin-Fiber Posts, Khalid Almulhim

Student Theses, Dissertations and Capstones

Background . Little is known about the long-term clinical bonding effectiveness of the Fiber-reinforced composite (FRC) posts cemented with self-etch adhesive systems. Bond stability and longevity of the cemented post are adversely affected by physical and chemical factors over time, such as expansion and contraction stresses caused by thermal changes and occlusal load. This clinical condition can be simulated in vitro by thermocyclic loading; and bonding effectiveness can be evaluated by applying the micropush out test. Therefore, more in vitro studies are needed to evaluate the bond strength of the fiber posts cemented with different resin cement systems after simulating …