Orthodontics and Orthodontology Commons^™

Facial Type Analysis Comparison Between Mri, Cbct, And Lateral Cephalometrics, Matthew A. Sanders

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Single Cephalometric measurements are comparable between Cone Beam Computed Tomography (CBCT), Magnetic Resonance Imaging (MRl) and Conventional Lateral Cephalometric (LC) imaging methods. This study evaluated the agreement between the three imaging methods in facial type analysis (using a composite of 5 cephalometric measures).

Methods and Materials: Twenty-two subjects participated in this study. Cranial images were generated via three modalities: LC, CBCT and MRl. Cephalometric landmarks were identified on the three images per subject and a facial type analysis performed. An equally weighted facial type calculation composed of 5 cephalometric measurements (facial axis, facial depth, mandibular plane, lower face height, …

A Cephalometric Study Of The Class Ii Correction Effects Of The Eureka Spring, Ernest L. Stromeyer

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of the Eureka Spring appliance, was investigated on 37 consecutively treated, non compliant, bilateral Class II malocclusions, requiring at least 3 mm or more of additional molar correction. The mean pretreatment age of this sample was 13.9 years. All patients were treated by a single clinician utilizing the Eureka Spring. Lateral cephalographs were taken at start of orthodontic treatment (T1), at insertion of Eureka Springs (T2), and at removal of the Eureka Springs (T3). The average treatment interval between T2 and T3 was 4 months. Class II correction occurred almost entirely by dentoalveolar movement, 33% in the maxilla …

Space Closure Efficiency With Modified Ceramic Brackets : A Comparative Study, Kirk A. Specht

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine if the rate of extraction site closure was determined by the type of ceramic bracket used. A new ceramic bracket with a metal archwire slot was compared with a conventional ceramic bracket. Twenty patients were randomly assigned the metal slot ceramic bracket and conventional ceramic to one half of their maxillary arch respectively. The distribution was even left and right.

Retraction was started and completed on an 0.016" stainless steel round continuous archwire. One hundred gram sentalloy springs provided a uniform retraction force and were reactivated every four weeks to maintain a …

The Fracture Strength Of Ceramic Brackets : An Update And Comparison, Christian P. Manley

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to compare the fracture strength of ceramic brackets which are currently on the market with ceramic brackets tested in a previous study at Loma Linda. Fracture strengths of standard edgewise ceramic brackets vs. pre-torqued ceramic brackets and bicuspid ceramic brackets vs. central incisor ceramic brackets were also compared.

A total of 160 Polycrystalline brackets, 8 categories in groups if 20, were tested for fracture strength. Each bracket was tested using the same testing model that was used in the previous study at Loma Linda. The brackets were tested by torquing a wire within the …

Amount Of Root Shortening Related To Type Of Fixed Appliance : A Comparison Of The 0.018" And 0.022" Bracket Slot, Thomas L. Thompson

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine if a different incidence and severity of maxillary incisor apical root resorption occurs in cases treated with the 0.018 inch versus 0.022 inch slot in standard edgewise mechanics. A consecutively treated sample of 240 patients (98 boys and 142 girls), with a mean age of 13.4 years from the orthodontic clinic at Loma Linda University were studied. 120 of the cases were treated using 0.018" bracket slot with standard edgewise mechanics and 120 were treated using 0.022" non-torqued full banded standard edgewise mechanics. 60 of the cases in each of the above …

Orthodontic Information Systems : A Developmental Study, Gary D. Sheldon

Loma Linda University Electronic Theses, Dissertations & Projects

The intent of this study was to design and implement a computer-based orthodontic system providing an integrated information environment throughout the entire patient treatment process.

Total system integration was achieved by restructuring the entire information gathering process. A complete, evaluation of patient diagnosis and treatment evaluation procedures established five major information categories and a critical information list for proper patient management. Information organization was outlined to provide a logical progression in the information gathering process and patient chart forms were designed to implement this. Defining the computer system's performance identified three functions as follows: 1) entry and editing of individual …

Comparative In Vitro Studies On Bond Strength And Sealant Polymerization, Gerald E. Sievers

Loma Linda University Electronic Theses, Dissertations & Projects

A comparison of two orthodontic sealants and two adhesives was made. An experimental adhesive was tested (Unitek*) also an experimental sealant (Unitek**) was evaluated for its ability to polymerize into a thin film. An established adhesive and sealant system (Concise***) was compared with the above products.

The factors which were considered important to the study were: the strength of the bond formed; the working efficiency; the ability for these materials to bond to the lingual of teeth; and the value of using contralateral teeth when testing bond strength.

An Instron testing machine was used to record the shear strength of …

Methodology In Measurement Of Load Loss Or Gain In Orthodontic Wires : A Pilot Study, Merton S. Lacy

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this investigation was to develop methods and equipment to measure and record over any desired length of time the loss or gain in force of any material used in orthodontics that can produce a force upon an object. The material and the object being acted upon should not be disturbed while measuring that force.

Holding devices were designed and constructed in two basic forms. For intrusive and extrusive type forces, a load cell was fixed horizontally in such a position that an adjustable tube with a set screw to hold the wire could be rotated to cause …

Fatigue Properties Of Orthodontic Wire, Kirkland B. Reuer

Loma Linda University Electronic Theses, Dissertations & Projects

Fracture of orthodontic appliances can be a problem because of the time involved to replace and repair them. It has been shown that most failures have been a result of fatigue fracture, i.e., failure resulting from cyclic loading.

The purpose of this study was to determine what effect variation of the type of orthodontic wire and heat treatment had on fatigue resistance. A device was constructed to put a cyclic load on a piece of wire until fracture. Two types of cobalt-chromium alloy wire (Blue and Green Elgiloy from Rocky Mountain Orthodontics) and three types of stain less steel wire …

A Study Of Treatment And Cephalometric Variables In Relation To Facial Axis Change During Treatment In A Dolichofacial Sample, Laurence A. Seifert

Loma Linda University Electronic Theses, Dissertations & Projects

The change in the facial axis in a sample of fifth-three dolichofacial patients, was compared with a number of pretreatment cephalometric variables. A number of treatment variables were also compared with the amount of facial axis change that occurred during orthodontic treatment.

The cephalometric variables measured were:

1. Facial axis
2. Upper face height (maxillary height)
3. Lower face height
4. Posterior face height
5. Mandibular arc
6. Palatal-mandibular plane
7. Palatal-occlusal plane
8. Occlusal-mandibular plane
9. Overbite
10. Upper first molar to palatal plane
11. Lower first molar to mandibular plane
12. Lower incisor to mandibular plane
13. Incisal edge of lower incisor to mandibular plane
14. Xi point to occlusal plane

Treatment …

An Analysis Of Orthodontic Treatment Results Employing Class Ii Armstrong Adjustable Intermaxillary Springs, Michael E. Shumate

Loma Linda University Electronic Theses, Dissertations & Projects

A study of orthodontic treatment results employing Class II Armstrong Adjustable Intermaxillary Springs was made on twenty-eight randomly selected patients which were treated by Dr. Maclay Armstrong.

The skeletal and dental changes observed during treatment with the Class II springs was compared with those results observed when comparable type malocclusions were treated with Class II elastics. A list of changes which were observed during treatment with Class II elastics was compiled from the literature using individual studies published by Ricketts, Creekmore and Hanes.

The study was based on the findings observed in the initial and final cephalometric radiographs. A statistical …

Craniofacial Changes Resulting From Expansion Of The Midpalatal Suture In The Macaca Mulatta Monkey As Revealed By Roentgenographic Analysis, Raymond M. Sugiyama

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine the effects of midpalatal suture separation on the craniofacial complex by quantitative roentgenographic analysis.

Ten female Macaca mulatta monkeys were randomly grouped for experimentation. Six animals were paired in groups for two months of treatment, four months of treatment followed by two months of post retention, and six months of treatment. The four remaining monkeys were paired and served as control animals for two and six month periods. Total activation of the expansion appliances in the treated animals was completed over a three week period.

The findings of this study were based …

An Odontometric Study Of Five Contemporary Western United States Indian And Alaskan Eskimo Groups, John A. Matis

Loma Linda University Electronic Theses, Dissertations & Projects

The morphologic characteristics of the oral cavity in five contemporary Western Indian and Alaskan Eskimo groups have been investigated by the use of study models of the dental archs. The sample consisted of 216 individuals, including 44 Navajos, 43 Apaches, 40 Papagos, 42 Pimas and 47 Alaskan Eskimos.

The first purpose of the study was to determine the extent of investigator error. This was accomplished by remeasuring many morphologic traits of the dentition in 125 Indians which had previously been measured by different investigators using the same study models. It was found that investigator error can be significant, even in …

The Facial Complex Of The Mayo Indian: A Radiographic Cephalometric Study, David G. Webster

Loma Linda University Electronic Theses, Dissertations & Projects

In order to investigate the characteristics of the facial complex of the Mayo Indian and to make comparisons between the facial complex of the Mayo Indian and the facial complex observed in other ethnic groups, measures of facial angles and linear relationships were obtained from a group of Mayo Indians in the state of Sonora, Mexico.

A simple of thirty subjects, seventeen boys and thirteen girls, with a mean age of 18.3 years was selected for this study. The criteria for selection was based on the integrity of the dental arches, occlusion and tooth morphology. Plaster casts and cephalometric x-rays …

The Efficacy Of A Limited Clinical Undergraduate Orthodontic Program, Benjamin H. Robson

Loma Linda University Electronic Theses, Dissertations & Projects

One of the major and long standing problems in undergraduate education has been the operation and maintenance of an efficient orthodontic clinic.

Literature based on the history of undergraduate orthodontic clinics, as well as of previous investigations into their operations was reviewed. Little if any, specific recorded information could be found.

The specific purpose of this investigation was to inspect the elements of and the accomplishments of a specific undergraduate orthodontic clinic. The efficacy was based upon an investigation along two avenues of study: (1) A complete review of all case histories and records for an analysis of the nature …