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Full-Text Articles in Orthodontics and Orthodontology

Condylar Angulations As Related To Submental-Vertex Radiographs, Jady L. Chiakowsky Jun 1992

Condylar Angulations As Related To Submental-Vertex Radiographs, Jady L. Chiakowsky

Loma Linda University Electronic Theses, Dissertations & Projects

Pretreatment submental-vertex radiographs were obtained for 637 adolescent patients (307 males, 330 females) who had presented themselves for orthodontic treatment. The purpose of this study was to: (1) determine the relationship between condylar angulations and depth of cut with the variables: age, sex, and race, and (2) establish normative values for the categories studied. The results indicated that no significant differences existed between the condylar angulations for the variables measured. However, significant differences did exist between the depth of cut for the variables measured and there was significant interaction between age and race with respect to the depth of cut. …


The Fracture Strength Of Ceramic Brackets : An Update And Comparison, Christian P. Manley Jun 1991

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 …


The Accuracy Of Sonographic Imaging (Dolphintm Digigraph) And Standard Lateral Cephalometric Radiographs : A Comparative Study, Michael D. Teichman Jun 1991

The Accuracy Of Sonographic Imaging (Dolphintm Digigraph) And Standard Lateral Cephalometric Radiographs : A Comparative Study, Michael D. Teichman

Loma Linda University Electronic Theses, Dissertations & Projects

Radiation due to x-ray exposure is a concern, and the development of the Dolphin™ DigiGraph represents an attempt to limit this exposure. The purpose of this paper was to compare measurements (using Ricketts analysis) obtained from conventional radiographic cephalometric tracings with those obtained by computerized digitizing with the DigiGraph. Forty-six patients from the Loma Linda University School of Dentistry graduate orthodontic clinic were digitized, and the results were compared to the x-ray tracings of these patients. The results showed that seven of the twenty-one variables examined exhibited a statistical similarity between the two methods (DigiGraph and x-ray tracing). An examination …


A Modified Nance Unilateral Molar Distalizer, Tracy J. Reiner Jun 1990

A Modified Nance Unilateral Molar Distalizer, Tracy J. Reiner

Loma Linda University Electronic Theses, Dissertations & Projects

This clinical study evaluated a modified Nance appliance designed by the author to distalize molars unilaterally for Class II correction. This fixed appliance did not rely upon extraoral traction or intraoral elastics. Twelve unilateral Class II patients aged 13 to 17 were treated nonextraction with the appliance. Pretreatment and posttreatment photographs were taken of the palatal soft tissue and did not reveal any untoward changes as a result of the Nance acrylic button. All molars were corrected to an Angle's Class I relationship. Molar correction was evaluated visually and molar distalization was measured using an acrylic jig fitted to the …


Feasibility Of An Extraoral Method For Predicting Manibular Incisor Relapse, Mark J. Saylor Jun 1989

Feasibility Of An Extraoral Method For Predicting Manibular Incisor Relapse, Mark J. Saylor

Loma Linda University Electronic Theses, Dissertations & Projects

The author undertook to develop an extraoral model for predicting mandibular incisor relapse similar to the model described by Harvey and Sheldon Peck. Whereas the Peck and Peck method involves intraoral measurements, the method described in this paper relied on the taking of measurements from the patient's pre-treatment plaster models. Two hundred and sixty teeth were measured both orally and on plaster casts, and several statistical tests were performed to isolate any differences between the intraoral and extraoral methods. The principal difference was identified as the faciolingual measurement of the incisor, due to the height of contour often being subgingival …


Facial Typing Methods : A Comparative Study, James A. Grabow Jun 1989

Facial Typing Methods : A Comparative Study, James A. Grabow

Loma Linda University Electronic Theses, Dissertations & Projects

Facial typing methods are used to determine to which of three basic facial pattern categories an individual patient belongs. These three categories are mesofacial, brachyfacial, and dolichofacial. It is important to establish the correct facial type because the reaction to treatment mechanics and the stability of the denture is dependent upon the analysis of the facial patterns. The purpose of this paper was to show a comparative study of facial typing classification methods used on 100 patients (47 boys and 53 girls). The eight different methods used were as follows: Bioprogressive, Ricketts LLU1, LLU2, QuickCeph™, Jarabak, Facial-Mandibular Index, and Steiner. …


The Incidence And Magnitude Of Tooth-Size Discrepancies In Caucasians, Blacks And Hispanics, Dana R. Shaltry Jun 1987

The Incidence And Magnitude Of Tooth-Size Discrepancies In Caucasians, Blacks And Hispanics, Dana R. Shaltry

Loma Linda University Electronic Theses, Dissertations & Projects

The present investigation utilized the Bolton Analysis to determine the incidence and magnitude of tooth-size discrepancy in a sample of 227 orthodontic patients. Sliding calipers were used to measure the mesiodistal width of the permanent dentition on pretreatment study models of 120 Caucasian, 51 Black, and 56 Hispanic patients. The overall and anterior ratios were analyzed and the frequency and magnitude of excess maxillary and mandibular tooth structure was determined. Each racial group demonstrated a significant incidence of tooth-size discrepancy in the maxillary and mandibular arches of a magnitude (> 0.5mm) which would require some form of correction. In addition, …


Amount Of Root Shortening Related To Type Of Fixed Appliance : A Comparison Of The 0.018" And 0.022" Bracket Slot, Thomas L. Thompson Jun 1986

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 …


Quick Ceph™, A Computer Program For Cephalometric Analysis And Treatment Planning, Günther Blaseio Jun 1986

Quick Ceph™, A Computer Program For Cephalometric Analysis And Treatment Planning, Günther Blaseio

Loma Linda University Electronic Theses, Dissertations & Projects

The quantification of cephalometric radiographs is an integral part of orthodontic treatment planning. Numerous computer programs have been designed to digitize headfilms and to provide accurate graphic output and exact measurements. Yet these early systems were either huge, bulky and expensive or were limited in their practical use. The aim of this development was to combine modern computer and electronic equipment with advanced software engineering. The result is a universal cephalometric program written in the computer language "C" with presently seven standard and virtually limitless user definable analyses, growth forecasting, mouse-driven interactive VTO, arch length calculation, superimpositions, table of values …


Third Molar Eruption Prediction, Michael L. Jacobsen Jun 1984

Third Molar Eruption Prediction, Michael L. Jacobsen

Loma Linda University Electronic Theses, Dissertations & Projects

The diagnosis and treatment of third molars has often been cited as a special problem to the orthodontist. If the prognosis of third molars could be determined, orthodontic treatment could progress on a more positive basis.

This study was designed to provide a method of deciding whether developing third molars will erupt or become impacted.

Records from 130 orthodontically treated cases of Dr. Fredsall8 were studied. Several factors were evaluated and measured using the patients' cephalometric radiographs.

The actual fate of the third molars were recorded in the hope it could be used to predict what to expect from …


Mandibular Repositioning With Frankel Appliance Therapy, Clark E. Schneekluth Jun 1983

Mandibular Repositioning With Frankel Appliance Therapy, Clark E. Schneekluth

Loma Linda University Electronic Theses, Dissertations & Projects

A sample of twelve Frankel appliance (FR-2) treated patients, in the mixed dentition stage, were selectively chosen by an orthodontist based on the Class II correction and evaluated from before treatment and end of treatment laminagraphic and lateral cephalometric radiographs. The average treatment period was 22 months (1 yr. 10 mos.). The average pre-treatment age was 9.5 years with a range from 8 to 11 years old, while the average post-treatment age was 11.3 years with a range of 10 to 13 years.

Frankel appliance therapy was the only form of mechanics used in this study.

The before treatment lateral …


Orthodontic Information Systems : A Developmental Study, Gary D. Sheldon Jun 1983

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 Jan 1981

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 Jun 1980

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 …


Treatment Of Persistent Open-Bite Malocclusions With Interarch Elastic Fixation, Kent L. Phillips Jun 1979

Treatment Of Persistent Open-Bite Malocclusions With Interarch Elastic Fixation, Kent L. Phillips

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to investigate the changes in the facial complex after treatment of persistent anterior open-bites with Dr. R. M. Ricketts' "squeeze treatment." This treatment method requires heavy elastic fixation for one month in conjunction with placement of T-loop arches.

Twelve open-bite patients were selected for the study. Quantative[sic] measurements from lateral cephalometric and laminagraphs of the temporomandibular joint were also evaluated. Qualitative observations were obtained from the periapical radiographs, models, and photos.

Tooth extrusion occurred in varying amounts followed by alveolar crest and apical repair.

Statistical significance was shown in the correction of incisor overbite, …


Fatigue Properties Of Orthodontic Wire, Kirkland B. Reuer Jun 1979

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 Cephalometric Evaluation Of The Dentofacial Changes Effected With Non-Extraction Treatment Utilizing Class Ii Intermaxillary Elastics, Sing Autrapiromsook May 1979

A Cephalometric Evaluation Of The Dentofacial Changes Effected With Non-Extraction Treatment Utilizing Class Ii Intermaxillary Elastics, Sing Autrapiromsook

Loma Linda University Electronic Theses, Dissertations & Projects

The effects of Class II intermaxillary elastics were studied by means of serial cephalometric records on 24 Class II malocclusions. All of the cases were non-extraction and no headgear was employed. Lateral cephalometric radiographs were taken prior to, and immediately following, the removal of the elastics. The amount of normal, growth adjustments was considered in all measurements. Molar movement and anatomical plane changes were analyzed statistically. The Student t-test were used to evaluate the significant changes.

The following conclusions are based upon a statistical analysis of the observed changes:

  1. The maxillary first molars did not move distally with respect to …


A Study Of Treatment And Cephalometric Variables In Relation To Facial Axis Change During Treatment In A Dolichofacial Sample, Laurence A. Seifert Jun 1978

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 …


Xeroradiography & Conventional Radiography : Comparative Imaging Of The Temporomandibular Joint, Nelson R. Gatov Jun 1977

Xeroradiography & Conventional Radiography : Comparative Imaging Of The Temporomandibular Joint, Nelson R. Gatov

Loma Linda University Electronic Theses, Dissertations & Projects

An investigation was conducted to evaluate the application of Xeroradiography for imaging the Temporomandibular Joint using the Updegrave and Weinberg positioning boards and to compare these images to those obtained by conventional radiography using the same positioning boards.

A cadaver head in which three spherical radiopaque implants had been placed was used in this study. A General Electric Model 1000 (Dental Unit) was the source of radiation. The conventional radiographs were produced on Dupont Cronex 2DC film and processed by a Phillips 810 automatic processed by a Xerox "125 System".

MAGNIFICATION

A comparison of the implant sphere diameters and the …


A Cephalometric Study Of Mandibulo-Facial Disostosis In Monozygotic Twins Using Computerized Methods, Lyn M. Lamberton Jun 1974

A Cephalometric Study Of Mandibulo-Facial Disostosis In Monozygotic Twins Using Computerized Methods, Lyn M. Lamberton

Loma Linda University Electronic Theses, Dissertations & Projects

An investigation using computerized cephalometrics has been conducted to consider the cephalometric factors responsible for the characteristic appearance evident in individuals afflicted with Mandibulo-Facial Dysostosis. A pair of Negro monozygotic affected twins were studied using the other 10 non-affected members of the family as a control to minimize the environmental and hereditary factors. The Rocky Mountain Data System was utilized to analyze the lateral and frontal cephalometric radiographs of each individual using Ricketts Analysis and the data were subjected to statistical tests to determine the factors contributory to the syndrome. Age and size were considered and adjustments were made to …


Cephalometric Norms For The Mexican Population Using The Ricketts, Steinar, And Tweed Analyses, Eduardo A. Velarde May 1974

Cephalometric Norms For The Mexican Population Using The Ricketts, Steinar, And Tweed Analyses, Eduardo A. Velarde

Loma Linda University Electronic Theses, Dissertations & Projects

In order to investigate the characteristics of the facial complex of the Mexican and to compare them with the Caucasian, a sample of 40 subjects, 31 males and nine females, of Latin American origin from Chihuahua, Chihuahua, Mexico, with a mean age of 16.6 years, were selected for this study. The criteria for selection were visual and only individuals with clinical normal, Angle Class I occlusion were chosen.

Lateral head Roentgenograms were obtained and cephalometric evaluation of the Skeletal and Dental Pattern was carried out using the Ricketts, Steiner, and Tweed Analyses.

The mean values for the Mexican were compared …


The Theoretical Distribution Of Forces In The Rigid Component Of The Buccal Arch Positioner, Dennis H. Teruya Jun 1973

The Theoretical Distribution Of Forces In The Rigid Component Of The Buccal Arch Positioner, Dennis H. Teruya

Loma Linda University Electronic Theses, Dissertations & Projects

The distribution of an applied force to the rigid component of the Buccal Arch Positioner was determined with a theoretically formulated model. The rigid component was assumed to be a free body without the semi-rigid attachments and was evaluated at four points for the force distribution. The summation of the forces and the moments were equated to zero and were utilized to derive equations to solve for the unknown forces. The unknown forces at each point of the rigid component were solved for in terms of the given force applications.

A laterally directed force application at one of the posterior …


Cephalometrics For The Oral Surgeon In The Diagnosis Of Facial Deformities, Frederick J. Mantz Jun 1973

Cephalometrics For The Oral Surgeon In The Diagnosis Of Facial Deformities, Frederick J. Mantz

Loma Linda University Electronic Theses, Dissertations & Projects

Surgical orthodontics presents a challenge to the oral surgeon. By the nature of the oral surgeon's training and discipline he should be the one best qualified to treat the surgical aspect of the surgical orthodontic case. The establishment of a proper diagnosis and means of communication between the oral surgeon and orthodontist are essential in achieving a good final result for the surgically treated case. Fortunately, a scientific method of diagnosis is available that can provide both specialties with a common language. Computerized cephalometric analysis can provide the diagnosis and link of communication for the discussion of goals and treatment. …


A Clinical Comparison Of Six Orthodontic Techniques, Erik H. Madsen May 1972

A Clinical Comparison Of Six Orthodontic Techniques, Erik H. Madsen

Loma Linda University Electronic Theses, Dissertations & Projects

Controversy exists concerning the relative superiority of various orthodontic techniques because of the difficulties encountered in making comparative clinical studies of these techniques which are scientific and statistically meaningful. The purpose of this study was to clinically compare six different orthodontic techniques which are currently being taught, relative to a number of criteria, and to do it in a scientifically significant manner.

In order to eliminate as many of the irrelevant variables as possible, the patients were required to pass a relatively stringent screening to participate. Among other things, the patients had to have first molars in Class I relation …


A Computerized Study Of Midpalatal Suture Expansion, Clelan G. Ehrler May 1971

A Computerized Study Of Midpalatal Suture Expansion, Clelan G. Ehrler

Loma Linda University Electronic Theses, Dissertations & Projects

An investigation has been conducted to consider the effects of midpalatal suture expansion on the cranial-facial complex. Nine patients were treated that had constricted maxillae. Data was obtained from frontal and lateral headplate radiographs which were taken at four intervals during treatment. The Rocky Mountain Data Systems diagnosis was utilized to interpret the radiographic data.

The data from the nine cases were averaged to obtain a composit [sic] change at each of the four times.

Examination of the lateral headplate data revealed that no permanent significant alteration occurred to the positions of the mandible or maxilla in a vertical or …


An Analysis Of Orthodontic Treatment Results Employing Class Ii Armstrong Adjustable Intermaxillary Springs, Michael E. Shumate May 1970

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 …


A Comparative Roentgenographic Cephalometric Study Of The Facial Profile Of Orthodontic Patients Treated At Loma Linda University With Winners Of The "Smiles Of The Year" Contest, Romeo I. Stoll May 1970

A Comparative Roentgenographic Cephalometric Study Of The Facial Profile Of Orthodontic Patients Treated At Loma Linda University With Winners Of The "Smiles Of The Year" Contest, Romeo I. Stoll

Loma Linda University Electronic Theses, Dissertations & Projects

The "Smiles of the Year" winners and patients treated at Loma Linda University by the extraction or non-extraction approach were compared by linear and angular variables of skeletal, dental and soft tissue components. These findings were analyzed statistically to determine significant differences in the profile and detect the relationship between the integument and hard structures.

The following conclusions were drawn from this investigation to reflect the trend of treatment at Loma Linda University.

  1. After treatment the patients had less skeletal convexity, but were more convexity than established standards.
  2. The incisors of the patients treated by the extraction approach were less …


Craniofacial Changes Resulting From Expansion Of The Midpalatal Suture In The Macaca Mulatta Monkey As Revealed By Roentgenographic Analysis, Raymond M. Sugiyama Jun 1968

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 …


Masseter Muscle Position Relative To Skeletal Open Bite And Skeletal Closed Bite, Alonzo David Proctor Jun 1968

Masseter Muscle Position Relative To Skeletal Open Bite And Skeletal Closed Bite, Alonzo David Proctor

Loma Linda University Electronic Theses, Dissertations & Projects

Modification of cephalometric roentgenographic procedures provided a means to identify the anterior borders of the right and left masseter muscles and relate them to surrounding dentoskeletal elements. Attachment of short, stiff, wires to the cheeks in a position superficial to the anterior borders of the muscles, subsequent to palpation and prior to exposure of the roentgenographic film, was the procedure used. The bi-lateral images projected on the film were averaged and traced along with dentoskeletal elements including those associated with skeletal type. This line representing the anterior border of the musculature was used to assess muscle position in the vertical …


Roentgenographic Evaluation Of Nasion-Menton And Sella-Gonion Measurements And Their Relationship To The Mandibular Plane Angle, David I. Asatani Jun 1968

Roentgenographic Evaluation Of Nasion-Menton And Sella-Gonion Measurements And Their Relationship To The Mandibular Plane Angle, David I. Asatani

Loma Linda University Electronic Theses, Dissertations & Projects

A convenience sample of 480 Caucasians using original diagnostic cephalometric films was selected to evaluate the nasion-menton and sella-gonion distances and their relationship to the mandibular plane angle.

The anterior facial height was represented by the nasion-menton plane. The posterior facial height was represented by sella-gonion plane. The facial depth was represented by sella-nasion and menton-gonion planes. The mandibular plane angle was represented by the intersection of the sella-nasion and menton-gonion planes.

The descriptive data, correlation analysis, and regression analysis was calculated for the following groups: total sample, females, males, prepubertal and postpubertal ages and various mandibular plane angles of …