Analytical, Diagnostic and Therapeutic Techniques and Equipment Commons^™

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 …

Effects Of Furosemide And Oleic Acid On Thyroxine Binding To Isolated Pairs Of Thyroxine Binding Serum Proteins, Deborah Hustead

Loma Linda University Electronic Theses, Dissertations & Projects

Dosage dependent binding inhibition and redistribution of thyroxine (T₄) between three pairs of thyroxine binding serum proteins, TBG-TTR, TBG-albumin and TTR-albumin, by furosemide (0.0 to 1.0 mol/L) and oleic acid (0.0 to 0.10 mol/L) were studied using equilibrium dialysis with purified binding proteins at concentrations 1/200 of levels in normal human sera, separated across the dialysis membrane and competing for T₄.

Furosemide (1.0 mol/L) reduced TBG bound T₄ in both the TBG-TTR system and TBG-albumin system (>90% decrease) and inhibited T₄ binding to TTR in the TTR-albumin system (68% decrease) and to albumin …

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 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 …

An Assessment Of Three Different Forms Of Sterlization And Clinical Usage On Various Orthodontic Pin And Ligature Cutters : A Pilot Study, Warren L. Creed

Loma Linda University Electronic Theses, Dissertations & Projects

With an awareness of cross infection in dentistry and of AIDS (acquired immune deficiency syndrome), sterilization in the dental office has been brought to the public's attention by the news media. Much work has been done on which sterilization methods are acceptable but little has been written about the effects of sterilization procedures on the instruments themselves. In this study, 36 pin and ligature cutters were sterilized 250 cycles using three different methods of sterilization following the guidelines given by the Center for Disease Control (CDC). The cutters were examined for changes in lateral hinge movement, visual appearance and ordinal …

Digital Morphometry : A Taxonomy Of Morphological Filters And Feature Parameters With Application To Alzheimer's Disease Research, Andrew Mehnert

Theses: Doctorates and Masters

In this thesis the expression digital morphometry collectively describes all those procedures used to obtain quantitative measurements of objects within a two-dimensional digital image. Quantitative measurement is a two-step process: the application of geometrical transformations to extract the features of interest, and then the actual measurement of these features. With regard to the first step the morphological filters of mathematical morphology provide a wealth of suitable geometric transfomations. Traditional radiometric and spatial enhancement techniques provide an additional source of transformations. The second step is more classical (e.g. Underwood, 1970; Bookstein, 1978; and Weibull, 1980); yet here again mathematical morphology is …