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Full-Text Articles in Physical Sciences and Mathematics
Facial Type Analysis Comparison Between Mri, Cbct, And Lateral Cephalometrics, Matthew A. Sanders
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, …
Microct Study Of Critical-Sized Defects Restored With A New Rhbmp-2 Carrier, Joanne S. Kim
Microct Study Of Critical-Sized Defects Restored With A New Rhbmp-2 Carrier, Joanne S. Kim
Loma Linda University Electronic Theses, Dissertations & Projects
Introduction: Regenerating bone in critical-sized maxillofacial osseous defects remains a challenge. The utilization of recombinant human bone morphogenetic protein-2 (rhBMP-2) to form new bone has been shown to be a promising alternative to autogenous bone grafts, and the development of a carrier matrix to effectively deliver the rhBMP-2 has been identified as the critical factor necessary for the successful clinical application of rhBMP-2. The objective of this study was to perform a microCT analysis to examine the density of reconstructed bone using different rhBMP-2 carriers in critical-sized defects.
Material and Methods: Critical-sized defects (approximately 2.5 cm) were created in the …
Creating Prediction Models For Obstructive Sleep Apnea Based On Gender, Jeffrey Hwang
Creating Prediction Models For Obstructive Sleep Apnea Based On Gender, Jeffrey Hwang
Loma Linda University Electronic Theses, Dissertations & Projects
Introduction: Obstructive sleep apnea (OSA) is a common chronic disorder that is characterized by repetitive episodes of airflow cessation or reduction occurring during sleep as a result of partial or complete upper airway obstruction. These recurrent events have a tremendous impact on the cardiovascular system with a multitude of dangerous consequences. Numerous studies have been conducted determining etiological risk factors for OSA including anatomical predictors which have been observed with multiple imaging techniques. Cone beam computed tomography (CBCT) is a low-radiation mode of imaging that can be used to accurately identify anatomical landmarks and measure craniofacial relationships and airway dimensions. …
Observer Reliability Of Cephalometric Landmark Identification On 3-D Mr Images, Michael S. Pollack
Observer Reliability Of Cephalometric Landmark Identification On 3-D Mr Images, Michael S. Pollack
Loma Linda University Electronic Theses, Dissertations & Projects
Introduction: Cephalometric analysis is a cornerstone of orthodontic diagnosis, yet much information is lost when 3-dimensional structures are assessed with 2-dimensional methods. CBCT offers 3-dimensional imaging but at the cost of higher levels of ionizing radiation. Magnetic resonance imaging provides 3-dimensional imaging without ionizing radiation and additionally imparts visualization of soft tissue structures. Prior to employing MR images for cephalometric analysis, reliability of landmark identification must be assessed. The purpose of this study was to evaluate intra- and interobserver reliability in 3-dimensional landmark identification using MR images.
Materials and Methods: Fifteen cranial MR images (3.0 T, MP-RAGE) from subjects between …
Using Cone Beam Computed Tomography To Identify A Prediction Model For Obstructive Sleep Apnea, Jodi Parker
Using Cone Beam Computed Tomography To Identify A Prediction Model For Obstructive Sleep Apnea, Jodi Parker
Loma Linda University Electronic Theses, Dissertations & Projects
Introduction: Obstructive Sleep Apnea (OSA) patients have increased risk of morbidity and mortality. Early diagnosis may reduce morbidity and mortality. Prediction of OSA from imaging may help to identify OSA patients earlier in life. CBCT can be used for OSA diagnostic imaging due to its three-dimensional (3D) visualization of the upper airway and craniofacial complex. Magnification associated with conventional 2D radiography is eliminated with CBCT, and radiation to the patient is significantly less than previous modalities used to measure craniofacial & airway measurements associated with OSA. During a CBCT scan, the patient's image is taken supine, rather than the upright …
Orthodontic Mini-Implant Failure: Assessing The Relationship To Bone Quality Using Qcbct, Joshua Schneider
Orthodontic Mini-Implant Failure: Assessing The Relationship To Bone Quality Using Qcbct, Joshua Schneider
Loma Linda University Electronic Theses, Dissertations & Projects
The purpose of this study was to evaluate the cortical bone thickness (mm), cortical bone density (HU), and trabecular bone density (HU) of mini-implants sites in both the maxilla and mandible using QCBCT to determine if they had any effect on mini-implant failure rate. Patient characteristics (age, gender, facial type), mini-implant characteristics (date of placement, manufacturer, length, and diameter), and the mini-implant site (region) were also evaluated. One hundred and six mini-implants in 50 consecutive patients with complete patient records, CBCT information, and T1 radiographs were included in the study. Thirty-four of the 106 mini-implants were considered "failures" resulting in …
The Comparative Radiopacity Between Primary And Permanent Teeth, Robert C. Lee
The Comparative Radiopacity Between Primary And Permanent Teeth, Robert C. Lee
Loma Linda University Electronic Theses, Dissertations & Projects
Purpose: This in vitro study compared the radiopacity between human primary and permanent enamel and dentin. It also compared the radiopacity between human anterior and posterior teeth.
Methods: Extracted primary and permanent teeth were used in this study. One mm enamel and one mm dentin slices were cut from each extracted tooth. Radiographs were taken of each enamel and dentin specimen 1 mm in thickness along with an aluminum step-wedge using procedures specified in International Standards Organization (ISO) 4049:2000. A densitometer was used to measure the Optical Density (OD) of the radiographs of the specimen and the accompanying aluminum step-wedge. …
Cephalometric Analysis Using Magnetic Resonance Imaging, Wade A. Williams
Cephalometric Analysis Using Magnetic Resonance Imaging, Wade A. Williams
Loma Linda University Electronic Theses, Dissertations & Projects
Purpose: The purpose of this study was to determine if T1-weighted 3D magnetic resonance images performed at 3.0 Tesla could be used to conduct routine orthodontic cephalometric analysis.
Methods: Three cranial imaging methods were compared using sixteen non-growing subjects (10 male and 6 female) who were not claustrophobic, did not have any metallic restorations on the distal of first molars, had no medical implants and the female subjects were not pregnant. Sagittal cranial images were produced by three methods: (1) a digital lateral cephalometric (LC) radiograph (Orthophos XG Plus, SironaTM, Bensheim, Germany), (2) a 12-inch FOV cone beam …
Repeatability Of Serial Carotid Intima Media Thickness Scanning On Individual Subjects, Judi Nightingale
Repeatability Of Serial Carotid Intima Media Thickness Scanning On Individual Subjects, Judi Nightingale
Loma Linda University Electronic Theses, Dissertations & Projects
Background. Heart disease affects millions of Americans each year. In order to improve primary prevention, early risk identification is essential. B-mode ultrasound of the common carotid artery (CCA) intima-media thickness (IMT) assesses risk of a coronary event early in the process of plaque development. Because IMT changes are so small over time, in order to determine clinically significant versus clinically insignificant changes in IMT over a 12 month time period, a protocol is needed which can detect the least significant difference (LSD) of at least 0.030 mm.
Purpose. The purpose of this study was to develop and test a well-defined …
Accuracy Of The Newtom 3g™ In Measuring The Angle Of The Articular Eminence, Rehana Khan
Accuracy Of The Newtom 3g™ In Measuring The Angle Of The Articular Eminence, Rehana Khan
Loma Linda University Electronic Theses, Dissertations & Projects
The purpose of this study was to determine the accuracy of the Newtom 3G™ in determining the angulation of the articular eminence. The benefits of conducting this study were to provide additional uses for the standard records that are taken for the purposes of orthodontic treatment, as well as evaluate the Newtom 3G™ for accuracy in measuring the anatomy of the glenoid fossa. This study required 20 participants that volunteered to allow their records to be used. Records evaluated were the Newtom 3G™, impressions, and wax check bite registrations. The wax record was taken using the 'forced bite' technique to …
The Outcome Of Mta As A Root End Filling Material: A Long Term Evaluation, Christopher M. Sechrist
The Outcome Of Mta As A Root End Filling Material: A Long Term Evaluation, Christopher M. Sechrist
Loma Linda University Electronic Theses, Dissertations & Projects
Periradicular surgery is a viable option to save natural teeth when non-surgical treatment fails or when endodontic retreatment is not feasible or contraindicated. Laboratory and animal studies have demonstrated that MTA is biocompatible, provides an excellent seal against penetrating bacteria, and promotes hard tissue healing. The purpose of this study was to provide long term (>3 years) clinical evidence for its use as a root-end filling material in endodontics. The clinical records of 294 patients who had MTA used during endodontic treatment from 1996 to 2001 were reviewed. From these, 75 patients whose root end cavities had been filled …
Prevalence Of Degenerative Joint Disease In A Pre-Orthodontic Adolescent Sample, Marie Mansour
Prevalence Of Degenerative Joint Disease In A Pre-Orthodontic Adolescent Sample, Marie Mansour
Loma Linda University Electronic Theses, Dissertations & Projects
The purpose of this research was to determine a prevalence of degenerative joint disease in our pre-orthodontic adolescent patients age ten through seventeen. The prevalence was assessed according to gender. Severity of DJD was established for each patient and a "red flag" for diagnosis was identified. The purpose was also to establish norms for joint space for patients with and without degenerative joint disease. Correlations to distal condyle position and angle classification were described. 123 consecutive patients, 77 female and 46 male T1 NewTom records were reviewed. Severity of DJD was classified according to none, mild, moderate, and severe. Sagittal …
The Radiopacity Of 29 Resin Restorative Materials Compared To Enamel, Peter Lubisich Iv
The Radiopacity Of 29 Resin Restorative Materials Compared To Enamel, Peter Lubisich Iv
Loma Linda University Electronic Theses, Dissertations & Projects
The radiodensity of a composite resin can greatly influence a clinician's ability to analyze a restoration for failure. The purpose of this study was to determine the relative radiopacities of 29 resin restorative materials compared to enamel, and to verify the comparable radiopacity between shades of 23 of the restorative composite resin materials. Composite resin discs measuring >5mm in diameter and 2 mm in thickness were made and polymerized. Radiographs were taken of the composite resin discs, which included an aluminum step wedge for calibration and a densitometer was used to measure the radiodensity of the composite resin samples. The …
Quantification Of Bone Deposition In Onlay Bone Grafting, Gregory Alan Kammeyer
Quantification Of Bone Deposition In Onlay Bone Grafting, Gregory Alan Kammeyer
Loma Linda University Electronic Theses, Dissertations & Projects
The purpose of this study was to quantitatively evaluate; 1) mandibular posterior mono-cortical block onlay bone graft success rates 2) the amount of grafted bone retained after initial resorption in radiographic projections. Seven consecutive patients with 14 mandibular posterior implant sites requiring bone augmentation for implants of a standard 3.8mm x 10mm dimension were sought. Mono-cortical block bone grafts from the ipsilateral ascending ramus were placed then observed with two standardized CT scans, dividing them into two groups: Group A had the first CT at 4 weeks after graft placement and a second taken before Prosthodontic reconstruction, 36.7 weeks later. …
A Cephalometric Study Of The Class Ii Correction Effects Of The Eureka Spring, Ernest L. Stromeyer
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 …
Mandibular Asymmetry In Unilateral Class Ii Malocclusion : A Cephalometric Study, Raed Z. Moussa
Mandibular Asymmetry In Unilateral Class Ii Malocclusion : A Cephalometric Study, Raed Z. Moussa
Loma Linda University Electronic Theses, Dissertations & Projects
The purpose of this study is to evaluate skeletal and dental asymmetry in unilateral class II malocclusion. A study group of 25 unilateral subdivision patients was compared to 25 class I malocclusion patients serving as the control group. Submento-vertical and frontal radiographs were used for the evaluation. Symmetry was evaluated by comparing measurements between right and left sides for both groups and matching the middle points with the midsagittal axis. Statistical paired and simple t-test were used to evaluate the difference between the two sides for both groups. The measurements showed no significant skeletal and dental asymmetries except for three …
Soft Tissue Changes Of The Upper Lip Following Isolated Le Fort I Osteotomies, Kendall E. James
Soft Tissue Changes Of The Upper Lip Following Isolated Le Fort I Osteotomies, Kendall E. James
Loma Linda University Electronic Theses, Dissertations & Projects
Pre-operative (T-1) and post-operative (T-3) radiographs were obtained and traced for fifty-one non-growing patients who had undergone isolated Le Fort I osteotomies. These tracings were then digitized with the results arranged in a data file and subjected to statistical analysis. The purpose of this study was to establish ratios for certain hard to soft tissue movements that could be used to aid the clinician in post-surgical soft tissue profile prediction. The results showed that even though a large sample was used, individual patient variability remained high particularly in the horizontal directions. Most ratios found in this study were consistent with …
Condylar Angulations As Related To Submental-Vertex Radiographs, Jady L. Chiakowsky
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 Accuracy Of Sonographic Imaging (Dolphintm Digigraph) And Standard Lateral Cephalometric Radiographs : A Comparative Study, Michael D. Teichman
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 …
Quick Ceph™, A Computer Program For Cephalometric Analysis And Treatment Planning, Günther Blaseio
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
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
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 …
Treatment Of Persistent Open-Bite Malocclusions With Interarch Elastic Fixation, Kent L. Phillips
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, …
A Study Of Treatment And Cephalometric Variables In Relation To Facial Axis Change During Treatment In A Dolichofacial Sample, Laurence A. Seifert
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:
- Facial axis
- Upper face height (maxillary height)
- Lower face height
- Posterior face height
- Mandibular arc
- Palatal-mandibular plane
- Palatal-occlusal plane
- Occlusal-mandibular plane
- Overbite
- Upper first molar to palatal plane
- Lower first molar to mandibular plane
- Lower incisor to mandibular plane
- Incisal edge of lower incisor to mandibular plane
- Xi point to occlusal plane
Treatment …
Xeroradiography & Conventional Radiography : Comparative Imaging Of The Temporomandibular Joint, Nelson R. Gatov
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 …
Apical Closure Induction Using Bone Growth Factors And Mineral Trioxide Aggregate, Kenneth W. Tittle
Apical Closure Induction Using Bone Growth Factors And Mineral Trioxide Aggregate, Kenneth W. Tittle
Loma Linda University Electronic Theses, Dissertations & Projects
This study compared the ability of three different bone growth factor combinations with that of Ca(OH)2 to stimulate apical closure as well as the effectiveness of Mineral Trioxide Aggregate (MTA) as an apical barrier. Fifty-six roots of second and fourth mandibular premolars of seven six- month old beagle dogs were used. Periradicular lesions were created over a four week period. The canals were cleaned and shaped and filled with Ca(OH)2 for one week. They were then irrigated and received one of seven different treatments in a balanced design. Growth factors were placed in a carboxymethylcellulose carrier and delivered …
A Cephalometric Study Of Mandibulo-Facial Disostosis In Monozygotic Twins Using Computerized Methods, Lyn M. Lamberton
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
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
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 Method Of Analyzing Mandibular Movement, Richard B. Mccoy
A Method Of Analyzing Mandibular Movement, Richard B. Mccoy
Loma Linda University Electronic Theses, Dissertations & Projects
Mandibular movement is considered to be a fundamental factor in the study, analysis, and treatment of occlusion. For many years, dentists have realized that dental health depends upon the compatibility of mandibular movements and occlusion. This realization has led to the development of new methods and techniques for recording accurately and scientifically the movements of the mandible. In order for this data to be of scientific value, it must be stored in a usable form which is easily available for analysis.
The purpose of this research project was to develop a procedure for storing and recalling mandibular-movement information. Before such …