Orthodontics and Orthodontology Commons^™

A New Soft Tissue Analysis : To Establish Facial Esthetic Norms In Young Adult Females, Anne Béress

Loma Linda University Electronic Theses, Dissertations & Projects

Two hundred and fifty-five articles, books, and masters theses were reviewed for the most frequently applied soft tissue measurements in the literature in order to develop a new soft tissue analysis computer program that includes established soft tissue measurements and the newly developed globe analysis. A meta analysis of 20 normal occlusion studies, was performed to obtain mean values and standard deviations to form a large sample size. Inclusion criteria for articles in the meta analysis were normal occlusion, no orthodontic treatment, pleasing faces, statement on age, race, and lip position of the population. For the lateral view, angular and …

In Vitro Plaque Formation On Orthodontic Resin Sealants, Leland W. Pack

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to examine in vitro plaque formation on sealant coated enamel. The plaque growth on different types of sealants placed on enamel was compared to each other and to an unsealed enamel control. The antimicrobial properties of sealants were also studied.

Sealant coated bovine enamel disks were immersed in a S. mutans culture medium for four days. The amount of bacterial plaque formation was quantified by removing the deposit, suspending it in solution with subsequent serial dilution. Aliquots of the dilutions were then spread on blood agar plates and incubated for 48 hours. The number …

Treatment Effects Of The Edgewise Bioprogressive Herbst Appliance, Bernard C. Chang

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of the Edgewise Bioprogressive Herbst appliance, as described by Dr. Terry Dischinger, was investigated on 24 Class II, Division 1 malocclusions. Mean pretreatment age of this sample was 11.2 months. All patients were treated by Dischinger with a Bioprogressive Herbst appliance. Lateral cephalographs taken before, after Herbst appliance therapy, and after edgewise treatment were traced, then digitized into Quick Ceph™. Measurements were computed by the computer software. The following results were found: 1) Average treatment time was 9 months. 2) An overcorrected Class I relationship was achieved. 3) Class II malocclusion was corrected by 4.5 mm skeletal alteration …

The Accuracy Of Computer Video Imaging Prediction : Just Prior To Surgical Mandibular Advancement/Genioplasty Orthognathic Cases, Jason T. Chiakowsky

Loma Linda University Electronic Theses, Dissertations & Projects

The accuracy of the computer video imaging treatment prediction was investigated using Quick Ceph Image.™ Thirty one surgical mandibular advancement/genioplasty orthognathic cases were examined to determine if the soft tissue profile prediction was representative of the actual result. All patients were over the age of 18. Lateral cephalographs and slides were taken immediately pre-surgically, and six months post-surgically. The slides were duplicated into 4X6 photographs. The cephalographs were digitized and the photographs captured by video on the Quick Ceph Image software program. A line drawing and computer video image treatment prediction were generated using the actual surgical change that had …

Current Theories On The Cell Biology Associated With Tooth Movement, Mohamadreza Yazdi

Loma Linda University Electronic Theses, Dissertations & Projects

This article discusses the current information on the mechanism of the biological signaling that takes place to bring about orthodontic tooth movement.

Currently, there are two general theories as to how orthodontic mechanical force is translated to biologically meaningful signals for the cells of the periodontium. These include a cellular-humoral response and a bioelectric response.

There are various mechanisms utilized by the cells of the periodontium to bring about the cellular-humoral response. These include: The activation of the cells of the immune system to synthesize and release specific chemicals (cytokines) which affect cell function, direct effects of mechanical force on …

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 …

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 Rotations Of Maxillary Molars, Mandibular Molars, And Maxillary First Premolars In Acceptable Occlusions, G. Kristian Hansen

Loma Linda University Electronic Theses, Dissertations & Projects

The rotation of the maxillary molars is considered important in the orthodontic treatment of malocclusions. In this study a computer analysis program was developed to examine the rotations of maxillary molars, mandibular molars, and maxillary first premolars in casts of permanent dentitions with acceptable occlusions. Ninety three sets of untreated "acceptable occlusion" models from the collection of the Foundation for Orthodontic Research (FOR) were scanned on a flat bed scanner at 600 dots per inch (dpi). The images were analyzed using custom software on a computer. Measurements were made by relating maxillary first permanent molars to the midline, the archform, …

A Comparison Of Retentive Strengths Of Two Types Of Inner Surface Treatments Of Orthodontic Bands, Jean M. Rathbun

Loma Linda University Electronic Theses, Dissertations & Projects

Band failure during orthodontic treatment results in a potential for decalcification and/or caries and may cause a prolonged treatment time. An increase in the bond strength at the cement/band interface would likely decrease clinical band failure. Sand-blasting and photo-etching have been suggested to improve this bond.

This study investigated the retentive strengths of untreated orthodontic bands, sand-blasted bands and photo-etched bands when cemented with glass polyalkenoate cement on extracted human molars. The sand-blasted bands and photo-etched bands were both found to have significantly stronger bond strengths (p

The Effects Of Rapid Palatal Expansion Therapy On The Periodontal Tissues Of The Central Incisors, Richard Gutierrez

Loma Linda University Electronic Theses, Dissertations & Projects

The periodontal structures around the maxillary central incisors in thirty-nine post-orthodontically treated patients, twenty-five of these patients had experienced Rapid Palatal Expansion (RPE), were examined to determine the periodontal consequences associated with two ways of managing the resultant diastema. In fourteen patients the diastema closure was assisted by elastomeric chain and in eleven patients the diastema closure was not assisted. Fourteen non-RPE orthodontically treated patients served as controls. Height of attached gingiva, gingival sulcus depth, attachment level, and alveolar bone level were recorded. One examiner, using calibrated techniques, performed all the measurements. The RPE groups and the control group all …

Plastic Deformation Of A Polycarbonate Bracket : Utilizing A New Testing Apparatus, Terri L. Alfred

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to investigate the plastic (permanent) deformation of a polycarbonate bracket (Miura, RMO) under the following different conditions: (1) untreated, (2) immersed in 37°C-water for 120 days, and (3) immersed in 60°C-water for 24 hours. Ten brackets for each condition were tested, with a total of 30 brackets tested. Each bracket was bonded to a metal mesh pad which was tack welded to a solid stainless steel ring. The assembly was placed under a loading frame. This loading frame removes variables such as bond adhesive strengths, distortion of a wire used to deform the bracket …

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 …

Long-Term Posttreatment Upper Incisor Inclination : Relative To Facial Axis Angulation As A Measure For Incisor Placement, David Lawrence Sparks

Loma Linda University Electronic Theses, Dissertations & Projects

This study was designed to determine whether upper central incisor inclination approximated the facial axis, long-term, posttreatment, regardless of the initial malocclusion or immediate posttreatment incisor inclination. Lateral head films at pretreatment, immediate posttreatment and long-term posttreatment were traced and evaluated. The sample was divided into facial type. Angle classification and treatment type (extraction vs. non-extraction). Statistical analyses included means, standard deviations, confidence intervals, population t tests and chi-square tabulations.

The results revealed that the upper central incisor did not approximate the facial axis after a minimum of 7 years posttreatment. This failed to support the use of the facial …

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 …

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 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 …

The Insertional Attachment Of The Superior Head Of The Lateral Pterygoid Muscle To The Temporomandibular Joint Components In Humans: An Anatomic Investigation, Thomas Otto Dusek

Master's Theses

No abstract provided.

A Study Of Crown And Root Angulation On Maxillary First And Second Bicuspids, Craig A. Chamberlain

Loma Linda University Electronic Theses, Dissertations & Projects

Pre-adjusted bracket systems offer the clinician the convenience of working with both fewer in number and smaller in magnitude adjustments of an archwire. The purpose of this in vitro study was to examine the normal variations in crown angulation of individual maxillary bicuspids, in a simulated flat plane of occlusion, and how this relates to marginal ridge discrepancies. A second purpose of this study was to examine these same teeth for the angulations of the roots. Fifty maxillary first bicuspids and thirty eight second bicuspids from the Loma Linda University Dental School restorative dentistry department were, in a flat plane …

Soft Tissue Changes Of The Lower Lip Following Isolated Mandibular Advancement Osteotomies, Ronald Roy A. Simus

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to evaluate the soft tissue changes that occur following isolated mandibular advancement surgery. A sample of 70 non-growing patients were examined by tracing pre and post-operative radiographs. Then various landmarks were chosen and hand measured to determine hard and soft tissue changes. Significant correlations were found for many of the horizontal and vertical tissue landmarks and weaker correlations for all other landmarks. The decrease in the interlabial gap and the angular changes in the lower lip reflect the direction of surgical movement. The data from this study supports previous studies of smaller sample sizes …

An Evaluation Of Surface Enamel Damage Following The Debonding Of Ceramic Brackets : A Follow-Up Study, C. Steven Edney

Loma Linda University Electronic Theses, Dissertations & Projects

Surface enamel damage was evaluated after debonding ceramic brackets on forty-four bicuspid teeth. These teeth had been previously bonded with two different types of ceramic brackets. One of the brackets utilized a mechanical base for retention and the other bracket utilized a polycarbonate base for retention. The brackets were bonded to the respective teeth for a total of seven to ten days. After debonding, the teeth were extracted and evaluated with a scanning electron microscope. A metal bracket SEM scan was used for a control. The study concluded that: 1) all brackets alter the surface enamel, 2) metal brackets cause …

Assessment Of The Accuracy Of Three Methods Of Computerized Growth Prediction Of The Soft Tissue Profile, In Untreated Individuals, Pat Diciccio

Loma Linda University Electronic Theses, Dissertations & Projects

This study was performed to determine the accuracy and reliability of the long range growth predictions for profile structures by three computer software systems (QuickCeph™ for Apple Macintosh™ systems. Rocky Mountain Data Systems™ for IBM™ mainframe systems, and Facial Print™ for IBM™ personal computers), on untreated individuals. The total sample consisted of 90 Caucasian children from the Burlington Growth Centre. These were subdivided into groups of 15 children in each of mesiofacial, dolichofacial, and brachyfacial growth types for both males and females, with Angle class I occlusions, normal overbite, and normal overjet. Points measured consisted of 14 skeletal and soft …

A Non-Human Primate Model For Evaluating A Fenestration Corticotomy Technique, Philip G. M. Khng

Loma Linda University Electronic Theses, Dissertations & Projects

A study model has been designed to evaluate the effectiveness of a new fenestration corticotomy procedure in two non-human primates Macaca fasicularis.

The objective of this study was to evaluate the efficacy of a new conservative corticotomy procedure to facilitate dental translation using fenestrations. This pilot study compared treatment and control quadrants of each individual animal's maxilla and mandible with both having the same retraction appliance and force on the 2nd premolar following extraction of the 1st molars. The null hypothesis stated that there was no significant statistical difference between the new conservative corticotomy procedure (fenestrations) when compared with …

A Shear Bondstrength Evaluation Of Five Orthodontic Light-Cured Adhesives, Perry M. Unruh

Loma Linda University Electronic Theses, Dissertations & Projects

In this study, the shear bondstrengths of five commercially available orthodontic light-cured adhesives were evaluated with respect to two types of curing lights and various cure-times. A total of 160 Transcend brackets (mechanical retention) were utilized. The brackets were individually bonded to knurled stainless steel testing rings via the respective adhesives. Each bracket was sheared from the testing ring using an Instron machine. For each adhesive a 2, 5, 10, and 20 second cure-time, and an immediate, 5 minute, 20 minute, and 24 hour shear test time was employed. The adhesives were cured using high intensity and low intensity visible …

A Pilot Study On The Evaluation Of Short Term Effects Of Jasper Jumper Therapy, Eric D. Fraser

Loma Linda University Electronic Theses, Dissertations & Projects

Lateral cephalometric radiographs were obtained for ten patients treated with Jasper Jumper appliances from three locations. Pre and post-appliance measurements were compared to determine the cephalometric effects seen in this group of patients. All patients in this study exhibited mesofacial to brachyfacial growth patterns and were all of growing age. All patients were treated to Class I along the complete buccal segment. The results yielded the following conclusions: 1) the facial axis did not open and the lower face height did not increase significantly for this group of patients, 2) there is an intrusive effect delivered to the upper first …

Force Systems From T-Loop Orthodontic Space Closure Springs: The Effects Of Asymmetric Placement And Angulation On The Alpha-Beta Moment Differential, Andrew J. Kuhlberg

SoDM Masters Theses

No abstract provided.

New In Vivo And In Vitro Techniques For Quantification Of Lateral Force Levels That Cause Implants To Fail : A Progress Report On Monkey Research, V. Leroy Leggitt

Loma Linda University Electronic Theses, Dissertations & Projects

Two new techniques for quantification of forces generated by an expansion screw apparatus placed between pairs of cylindrical endosseous titanium implants are described, along with preliminary data gained from their use in Macaca rhesus monkeys. Strain gages were bonded to the expansion apparatus and were calibrated either directly by micro load cell, or indirectly by Instron Machine to reflect the applied force.

Immediate loads of up to 6 kilograms have been applied to the implants with no increase in mobility as verified by a Periotest device. No previous studies on the orthodontic uses of implants have evaluated in vivo forces …

An Evaluation Of Surface Enamel Damage Following The Debonding Of Ceramic Brackets : A Follow-Up Study, B. Scott Hood

Loma Linda University Electronic Theses, Dissertations & Projects

To evaluate surface enamel damage after debonding ceramic brackets using their manufacturer's recommended methods, sixty four bicuspid teeth were bonded with three different types of ceramic brackets and one type of metal bracket. All the brackets tested utilized mechanical retention only. The brackets were debonded in the mouth seven to ten days after bonding, extracted and evaluated with a scanning electron microscope. The study concluded that: 1) all brackets alter the surface enamel, 2) there is a significant difference in surface enamel damage between the metal bracket and the ceramic brackets utilizing a tensile debonding method, 3) there is no …

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

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. …

Predicting Post-Treatment Maxillary Lip Position : A Comparison Of Two Techniques, Kevin J. Andrews

Loma Linda University Electronic Theses, Dissertations & Projects

The objective of this study was to compare the "drape" technique as proposed by Economides with the Holdaway technique in predicting post-treatment maxillary lip position and to determine which method was more accurate. Pre and post-treatment lateral cephalograms were traced for ninety (Caucasian) cases equally divided by sex into three treatment groups: a) non-extraction with at least 4mm of upper incisor retraction, b) extraction of upper first bicuspids only, and c) extraction of all first bicuspids. VTO's were constructed as outlined by Economides (drape) and Holdaway for prediction of post-treatment maxillary lip position. The predicted lip positions were compared to …