Radiology Commons^™

Predictive Value Of Radiographic Analysis Of Menton, Hyoid Bone, And The Third Cervical Vertebra Angle, Kalfred G.S. Chun

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study is to determine if the hyoid bone could be used as a reliable and stable reference landmark. Previous researchers have used cranial landmarks to determine the hyoid bone position. The results of these studies have shown a large variability in hyoid position. To determine the hyoid bone position, an analysis called the hyoid triangle was used. The hyoid triangle is formed by joining the cephalometric points retrognathion (the most inferior posterior point on the mandibular symphysis), hyoidale (the most superior anterior point on the body of the hyoid bone), and C3 (the most anterior inferior …

A Comparison Of Enamel Detachments After Debonding Between Unitek's "Dynalok" Bracket And A Foil-Mesh Bracket: A Scanning Electron Microscope Study, Robert E. Meister

Loma Linda University Electronic Theses, Dissertations & Projects

The intent of this paper was to: 1. Evaluate the mode of adhesive failure when debonding both flexible and rigid base orthodontic brackets. 2. Evaluate the bracket bases for enamel detachments. 3. Measure the enamel detachments.

After preforming shear test on flexible and rigid base orthodontic brackets mounted to extracted human teeth it was determined that failure occurred at the enamel/adhesive interface 30% of the time, at the bracket/adhesive interface 10% of the time and a combination of these 60% of the time for both groups.

Five brackets from each group were evaluated for enamel detachments using energy dispersive x-ray …

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 …

A Correlation Study Of Facial Soft Tissue Proportions (Golden Sections) And Cephalometric Measurements Of Golden Sections And The Eleven Factor Analysis, Russell Andrew Sutliff

Loma Linda University Electronic Theses, Dissertations & Projects

Frontal photographs on a total of one hundred and three individuals who had been treated by Dr. Ricketts, and had been involved in a prior study at Rocky Mountain Data Systems, were evaluated for facial proportions according to Ricketts application of Pythagoras' golden section. Seven facial proportions were analyzed from 1:1 retention phase frontal photographs. Forty individuals, made up of twenty-two females and eighteen males, 12.2 to 21.0 years of age, were selected and divided into two groups of twenty each, according to their soft tissue facial proportions. A range of acceptability for the facial proportions was derived. Proportions within …

A Comparative Analysis Of Intrusion Of Incisor Teeth Achieved In Adults And Children According To Facial Type, Ronald L. Otto

Loma Linda University Electronic Theses, Dissertations & Projects

A comparison of incisor intrusion achieved in deep bite adults and children was made. Facial type was also examined for affect upon intrusion achieved. Fifty-five cases treated with Bioprogressive mechanics were studied cephalometrically, including twenty-four adults and thirty-one children. Neither age nor facial type was found to be statistically related to the amount of incisor intrusion achieved in this sample. A method of measuring intrusion at the root apices was devised which was felt to give a more accurate indication of actual bodily intrusion. More external root changes during treatment were observed for adults than for growing children. Wide latitude …

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 …

Cephalometric Objectives For The Maxillary Central Incisor, John Mickey Damerell

Loma Linda University Electronic Theses, Dissertations & Projects

A cephalometric study was conducted to determine the ideal inclination of the maxillary central incisor for various facial patterns. Selected measurements were made on lateral headplate tracings of three samples: ideal, random and Class III malocclusions. Statistical analysis of data included means, standard deviations, simple correlations and stepwise regressions.

The Frankfort plane was found to be the most reliable reference plane when measuring the inclination of the maxillary central incisor. The maxillary central incisor inclination was found to be dependent upon the lower incisor position and inclination, chin position and the anterior cranial base inclination. A formula was produced to …

Growth Augmentation With Activators, John R. Sibley

Loma Linda University Electronic Theses, Dissertations & Projects

This research was performed to determine if bony changes could be effected by activator treatment and how stable this treatment is.

From a sample of twenty-seven cases with before activator treatment cephalometric radiographs. Rocky Mountain Data Systems provided growth projections, with and without edgewise treatment, for the period of time each patient was in treatment. These forecasts were compared to the post-treatment cephalograms to analyze the orthopedic effects of activator treatment with normal growth and with edgewise therapy.

Nine of the twenty-seven case treated sample responded to recall for post-treatment cephalograms and were analyzed for relapse.

It was apparent that …

A Cephalometric Study Of Post-Retention Relapse In Mandibular Expansion Of Cuspids And Molars, Randall J. Schuler

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this research was to determine if the advancements of cephalometrics and the capacity of the computer to quantify skeletal relationships could help the orthodontist recognize those cases where arch length could be gained through buccal expansion with little risk of relapse. To determine the stability of orthodontic treatment changes, the mandibular arches of 72 patients were studied. The cases were treated by Drs. Bench and Ricketts and were selected on the basis that each case must include three complete sets of frontal and lateral headplates, before and after treatment, and a minimum of two years out of …

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

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 …

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. …

Kinesiology Of Knee Flexion Deformity Using Electromyography, Paul J. Roby

Loma Linda University Electronic Theses, Dissertations & Projects

A kinesiological electromyographic study was completed to determine the relative changes in muscle activity as a person walks and stands with different degrees of knee flexion deformity. The ultimate aim was to establish criteria for appropriate preventive and corrective measures relating to knee flexion deformity.

Six different muscles were implanted with wire electrodes. The subjects performed a series of walking and standing experiments with the knee flexed at selected angles by a locking leg brace to simulate knee flexion deformity. The electromyographic action potentials were monitored by analog tapes, oscilloscopes and closed circuit television. The analog tapes were displayed on …

Endodontic Sealing Properties Of Cavit, Chloro-Rosin Gutta Percha, N2, And Silver Cones Using Radioisotopes, Frank H. Beal

Loma Linda University Electronic Theses, Dissertations & Projects

The main purpose of this investigation was to test the endodontic sealing abilities of silver cones, N2, warm gutta percha, chemically softened gutta percha, laterally condensed gutta percha and Cavit under carefully controlled conditions. Evaluations were done by radiographic, macroscopic, microscopic, and autoradiographic examinations.

The four points which must be considered when evaluating the efficacy of sealing root canal systems, in vivo, were presented and discussed.

Cavit as a total endodontic filling material was presented, investigated and discussed.

An improvement of the chloro-rosin - gutta percha diffusion technique was presented.

The concept of surface as well as marginal leakage was …

A Clinical Evaluation Of The Light Progressive Technique During Cuspid And Anterior Retraction, Gary R. Keszler

Loma Linda University Electronic Theses, Dissertations & Projects

This study was conducted to clinically evaluate cuspid and anterior retraction in first bicuspid extraction cases using the Light Progressive Technique. More specifically interest was centered on rate of cuspid and anterior retraction, anchorage preservation or control, difficulty of appliance adjustments, time involved in adjustments, frequency of adjustments, total retraction time, patient discomfort, root resorption, as well as a complete cephalometric appraisal. Seven patients were treated for ten months. The appliance was activated at three week intervals, and progress recorded monthly.

It was shown that this technique maintains molar anchorage during rapid cuspid retraction without relying on patient cooperation for …

The Relationship Of The Bucco-Lingual Position Of The Mandibular First Molar To Occlusion And Arch Stability, Lothar M. Guttschuss

Loma Linda University Electronic Theses, Dissertations & Projects

Forty non-treated and twenty-two orthodontically treated cases were selected to determine the relationship of the bucco-lingual position of the mandibular first molar to occlusion and arch stability.

Plaster models and occlusal radiographs were obtained from all the cases. Anterior crowding, intermolar width, molar classification, and molar overhang relative to the basal bone were determined. The modified technique for occlusal radiographs used was found to result in radiographs which were more versatile and accurate when interchanged with the model measurements. Clinical applications of this technique include the determination of root angulations, location of impactions, and the fabrication of individualized preformed arch …

The Relationship Between The Lingual Surface Of The Maxillary Central Incisor And The Eminence Of The Mandibular Fossae, Robert A. Huffer

Loma Linda University Electronic Theses, Dissertations & Projects

Gnathologists have suggested that in order to prevent excessive wear on posterior teeth, alveolar bone loss due to traumatic occlusion, and temporomandibular Joint (TMJ) disturbances, the mandibular incisors should disclude the posterior teeth by moving along the lingual surfaces of the maxillary incisors as the condyles move down the articular eminence in protrusion. It is suggested that in order for this to occur, the lingual surface of the maxillary incisors should be steeper than the eminence.

A cephalometric technique was developed to accurately determine the anatomical form of the articular eminence. A regular orthodontic tracing of the head was done …

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 …

The Role Of The Articular Eminence In Mandibular Protrusion, Norman E. Corbett

Loma Linda University Electronic Theses, Dissertations & Projects

Since movements of the TMJ may be translatory, rotary, or both, the form of the articular eminence becomes an integral part of the anatomy of the joint and is important in an understanding of TMJ function. A cephalometric technique was developed to accurately determine the anatomical form of the articular eminence. From a series of cephalograms, taken in various mandibular positions, the protrusive condylar path was determined. This path was also determined from a gnathological recording technique. The paths obtained were observed to be the same. The condylar path and articular eminence curves were mathematically expressed by computer programmed quadratic …

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 …

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 …

The Advantages Of A Condyle-Gnathion Reference Line In Roentgenographic Cephalometry, Ernest N. Chan

Loma Linda University Electronic Theses, Dissertations & Projects

Evaluation of the cephalograms of 150 patients showed a wide range in the angulation of the lower border of the mandible to the various facial planes. The degree of this angulation did not always correspond with the severity of malocclusion. Group I represents normal occlusions, Group II comprises malocclusions.

A new reference line is submitted for the investigation of its advantages in cephalometric roentgenography. The mandibular radius drawn through the geometric center of the condyle to the point gnathion is correlated with several indices of facial growth, namely (1) ANB difference, (2) upper facial:lower facial height and (3) PoNB distance …

A Method To Determine Curved Surface Laminagraphic Width And Position In Panoral Radiography Utilizing The Panorex X-Ray Unit, Gary G. Morikone

Loma Linda University Electronic Theses, Dissertations & Projects

Although the Panorex X-ray unit has been in existence for almost a decade, no information is publicly available relative to the determination of its laminagraphic slice width or position.

In order to utilize the machine most effectively as a research tool, it seems imperative that this width and position be established.

For the purpose of establishing the spatial relationship within the exposure mechanism, the two eccentric rotational axes were first located. Utilizing a positioning device, ten panoral radiographs of a plastic working dummy with metallic implants were exposed at varying exposure readings. The resultant radiographs, revealing varying degrees of accuracy …

Development Of A Positioning Device For Use In Conjunction With Panoral Radiography, Ray M. Hymer

Loma Linda University Electronic Theses, Dissertations & Projects

A cephalometric positioning device has been developed for use on the XRM Panorex X-Ray machine. Tests have demonstrated that the variability in producing serial radiographs with this device is comparable to, or less than, that currently accepted in conventional radiographic cephalometry.

Two procedures for obtaining serial radiographs were employed. Two patients were used for the first procedure and three patients were used in the second procedure.

In the first procedure each patient was positioned in the device and two radiographs were taken in sequence without disturbing the patient.

In the second procedure three clinic patients were used as subjects and …

A Cephalometric Comparison Of The Chamula, Mayo And Navajo Indians, Norman C. Bunker

Loma Linda University Electronic Theses, Dissertations & Projects

Lateral head x-rays were obtained on selected samples of 24 Chamula, 29 Mayo and 39 Navajo Indians for cephalometric comparison.

Cephalometric evaluation was carried out by means of the Bjork analysis. Mean values for each of the Indian groups were determined and compared with each other and with the mean values of a group of Swedish conscripts studied by Bjork. The mean values were statistically analyzed and and subjected to the Student's "t" test to determine the significant levels of differences.

Results revealed that in comparing the three Indian groups significant differences do appear. They are few and general concordance …

A Comparative Study Of Two Contemporary Methods Of Cephalometric Analysis, Alden B. Chase

Loma Linda University Electronic Theses, Dissertations & Projects

A comparative cephalometric study was made of nineteen cases, fourteen of which were patients under treatment at the Department of Orthodontics, School of Dentistry, Loma Linda University. The remainder were individuals considered to have normal occlusions.

The review of the literature emphasized the plethora of analyses and the fact that cephalometry is a tool that must be mastered if the orthodontist is to give the best service. Thus the need for a study to compare the methods of analyzing the cephalograph. A study was made to compare two main methods of analysis and to determine whether or not the information …