Orthodontics and Orthodontology Commons^™

An Evaluation Of 17-4 Precipitation-Hardenable Stainless Steel Alloy For Use As An Orthodontic Wire, Martin G. Martz

Loma Linda University Electronic Theses, Dissertations & Projects

17-4 precipitation-hardenable stainless steel, a high strength alloy developed for aircraft applications, has been examined for possible use in orthodontics. The effects of solution treatment, various refrigeration treatments, and various aging treatments on standard tensile properties were measured. Comparisons were made with the tensile properties of 18-8 stainless steel and a Co-Cr alloy presently used in orthodontics.

Solution treatment was found to decrease ultimate strength by 37.8%, 0.2% yield strength by 45.9%, and (YS)/E ratio by 36.7%, while having almost no effect on elastic modulus or percentage elongation. Refrigeration treatments had statistically significant but small effects on tensile properties. Aging …

Effects Of Stress Relief To Decrease Force Loss In Retraction Springs, Richard Earl Dunn

Loma Linda University Electronic Theses, Dissertations & Projects

Orthodontic wire may be heat treated to relieve residual stresses resulting from the formation of bent configurations. This study utilized electronic equipment to detect and record the initial amount of activation force, and the amount of force lost due to the intrinsic properties of the wire. The information was gathered at three hour intervals over fifteen one-week periods. The data were statistically analyzed by a computer to deter mine means and standard deviations. A general linear hypothesis was utilized to test covariants and the main effects.

A total of forty-eight wires were tested. Closed he lix retraction springs fabricated from …

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 …

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 Of Subjective Ranking Of Facial Esthetics And The Golden Section Analysis, Timothy Robin York

Loma Linda University Electronic Theses, Dissertations & Projects

The objective of this study was to determine if faces which fit the golden sections as proposed by Ricketts were considered more esthetic to the layman than faces which did not fit the golden sections as well.

Frontal facial photographs of 92 individuals from the normal occlusion sample of Andrews were measured for facial proportions according to Ricketts application of the golden section. Seven facial proportions were computed from the photographs. Ten photographs were selected, five of males and five of females, representing a range of mean percent deviation from the golden section proportion (1.618). Randomly arranged sets of these …

A Comparison Of Two Rapid Palatal Expansion Appliances And Their Effect On Palatal Cross-Sectional Area, William D. Scott

Loma Linda University Electronic Theses, Dissertations & Projects

Two rapid palatal expansion appliances, acrylic-free and acrylic-reinforced, were compared for their effect on the cross-sectional area of the palate. Two groups, twenty-five patients in each, were selected so that they would match as closely as possible with regards to age and sex distribution. The pre-treatment and post-treatment maxillary models were duplicated, and this duplicate model was then trimmed in a specific manner to allow the cross-sectional area between the first permanent molars to be compared. The results indicate that there is no difference, at the five percent level of significance, between these two appliances. It is concluded that the …

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 …

Activator Growth Augmentation : A Long-Term Perspective, William Emmerson

Loma Linda University Electronic Theses, Dissertations & Projects

A sample of twenty-three activator treated patients, in the growth years up to age eighteen were evaluated at three time intervals, before treatment, end of treatment, and five years post-treatment. The average time period of the post-treatment evaluation period was 5.7 years after the end of active therapy. The patients' ages ranged from 8.4 to 13.3 years at the beginning of activator treatment.

In the correction of the Class II malocclusion, no other form of orthopedic mechanics were utilized in this sample. In some cases full banding was used to align and level the arches prior to the activator therapy. …

The Effects Of Second Molar Extractions In Conjunction With Bionator Treatment, Mohammed Toufic Jeiroudi

Loma Linda University Electronic Theses, Dissertations & Projects

The intent of this paper is to evaluate the effects of second molar extractions in conjunction with Bionator treatments. Eighteen Orthodontic patients were used in this study. All had had second molars extracted. Lateral cephalometric radiographs were traced and used to evaluate the treatment. The average age at time of extraction was 13 years, 3 months. The average treatment time was 38.3 months.

There were some orthopedic changes. The convexity decreased significantly, the condyle axis increased more than expected in normal growth. Also, the lower facial height and facial axis both became more dolichotype (open).

The upper and lower incisors …

Force Loss In Retraction Springs At 37°C As Affected By Time, Roger Edward Clawson

Loma Linda University Electronic Theses, Dissertations & Projects

Closed helix retraction springs fabricated from .016 X .016 inch Blue Elgiloy, Permachrome Standard stain less steel, and Multiphase orthodontic wire were tested at 37°C in their heat and nonheat treated condition to determine force relaxation properties. Electronic equipment consisting of load cells, regulated power supply, and an automatic recording device were used to measure force changes which occurred in the wire samples over a seven day period. A constant temperature was maintained by an ethylene glycol and water circulator. A temperature probe and an electronic thermometer monitored the 37°C water bath surrounding the wire samples. The data was graphed …

The Effects Of Orthodontic Repositioning Into A Surgically Expanded Site On Bone Formation And Tooth Mobility In A Baboon, Anthony B. Lier

Loma Linda University Electronic Theses, Dissertations & Projects

For sometime, expansion of the maxillary arch, by means of surgical and mechanical procedures, have been acknowledged with minimal attention directed toward the mandible. In this pilot study a surgical technique was employed in separating the mandible, A-P, at the symphysis. The interosseous void, approximately 10 mm., was then filled with autogenous bone marrow collected from the greater trochanter and the crest of the ilium.

The surgical site was then maintained for a period of eight (8) weeks with the aid of a precast chromium-cobalt splint and titanium mesh placed intradentally and at the symphysis, respectively. Following the stabilization period …

Time Vs. Force Relaxation In Utility Arches, Irvine Keith Corbett

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract not included]

A Comparative Study Of Tensile Properties In Five Orthodontic Wires, Charles B. Mcdermott

Loma Linda University Electronic Theses, Dissertations & Projects

The tensile properties of .017 x .025" stainless steel. Multiphase, Blue Elgiloy, beta titanium, and Nitinol were tested and compared. All wires were tested in the "as received" condition. Fifteen samples of each type of wire were tested in order to determine the (1) modulus of elasticity, (2) .2% yield strength, (3) ultimate tensile strength, (4) percentage elongation and (5) maximum elastic deflection.

The modulus of elasticity and .2% yield strength are the most important properties to orthodontists because of their influence on the wire's stiffness, strength and range. The ratio of yield strength/modulus of elasticity, termed maximum elastic deflection, …

The Effects Of Palatal Expansion Therapy On The Periodontal Supporting Tissues, Kenneth R. Greenbaum, Bjorn U. Zachrisson, John K. Pearson, Roland D. Walters, Jan Egelberg, James R. Wise, Grenith Zimmerman

Loma Linda University Electronic Theses, Dissertations & Projects

Four periodontal parameters were examined to determine the effect of rapid and slow palatal expansion techniques on the supporting structures at the buccal aspect of the maxillary first permanent molars. The parameters examined included the levels of crestal alveolar bone and soft tissue attachment (relative to the cemento-enamel junction), the depth of the gingival sulcus, and the height of the attached gingiva. The area between the buccal roots was inspected for possible furcation involvement. Twenty-eight patients had experienced a rapid technique utilizing a tissue-born, fixed, split-acrylic appliance, while thirty-three patients had been treated with the quad-helix appliance associated with slow …

The Effects Of Maxillary Quad-Helix Appliance Expansion On Cephalometric Measurements In Growing Orthodontic Patients, Steven Wesley Frank

Loma Linda University Electronic Theses, Dissertations & Projects

This study was conducted to examine the effects of maxillary quad-helix expansion on frontal and lateral cephalometric measurements in growing orthodontic patients. Twenty subjects, nine girls and eleven boys (x age = 10 years, 3 months), each exhibiting at least a unilateral posterior lingual cross-bite that had been treated with a maxillary quad-helix appliance, were selected for this study. Posterior-anterior and lateral cephalometric radio graphs were taken at the beginning of treatment (T₁), when the appliance was removed (T_prog' x time = nine months) and at retention (T₂) and subsequently traced. The T_{1 …}

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 …

A Comparative Study Of The Temporomandibular Joint Area Using Laminagraphic And Panographic Surveys, Frederec B. Cothren Ii

Loma Linda University Electronic Theses, Dissertations & Projects

The relative merits of laminagraphic and panographic radiographic images of the temporomandibular joint area have been compared.

Serial temporomandibular joint area radiographs were taken with a panographic unit. A dried human skull was used as the study subject. Wire grids were placed over the temporomandibular joint areas. The linear and angular distortion of the wire grids was measured with the plane of occlusion being serially tipped horizontally from minus fifteen degrees to plus fifteen degrees.

Lateral laminagraphs were then taken of the same skull with the wire grids still in place to determine the accuracy of the laminagraphic technique as …

Orthognathic Surgical Expansion Procedure Of The Mandible Of Female Baboon Papio Sp?, Willis L. Schlenker

Loma Linda University Electronic Theses, Dissertations & Projects

Expansion of the maxillae is a well recognized procedure in orthodontics. Little is known about Mandibular Expansion. This project is a pure research of the possibility of expanding the mandible laterally at the symphysis on a baboon.

The symphysis was cut A-P and expanded laterally 11 mm, then held and stabilized with a titanium mesh work screwed to the inferior border of the mandible. The defect area was filled with a bone graft of marrow and cancellous bone fragments taken from the greater trochanter and the crest of the ilium. New bone did fill in the defect and the expansion …

Third Molar Eruption Prediction: A Simplified Method, Lawrence E. Mcewen

Loma Linda University Electronic Theses, Dissertations & Projects

With the advent of lower third molar enucleation in the 7 to 10 year old comes the potential for abuse because the operation is fast and easy to perform. The rationale could be, "they will probably impact any way." If this is done without benefit of a growth forecast to project future dental needs a great disservice may be performed.

This study was designed to provide a simplified method to predict space for the lower third molar. Frankfort Horizontal (FH), Pterygoid Root Vertical (PTV), Xi, Upper first molar and lower second molar were the major landmarks to be used on …

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

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 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 …

Anterior Maxillary Soft And Hard Tissue Change : An Evaluation Of Orthodontic And Orthognathic Treatment Results, Joseph H. Elison

Loma Linda University Electronic Theses, Dissertations & Projects

Soft and hard tissue changes, in the nasolahial angle and the region of the upper lip, were compared in two modes of treating Class II, Division 1 maloclussion: 1) extraction of the upper first bicuspids and retraction of the anterior segment surgically by means of the Anterior Maxillary Osteotomy CAMO), 2) extraction of upper first bi cuspids and retraction of the anterior teeth by orthodontics alone. The first group consisted of twenty-five (25) patients; the second group consisted of thirty-six C36) patients.

Analysis of the resulting changes demonstrated the following:

With surgery ANS was retracted 2.52 mm, "A Point" was …

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

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

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 …

Cranio-Facial Skeletal Morphology Of Digit Suckers, John Eric Peterson Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this paper was to investigate the cranio-facial skeletal morphology found in digit suckers.

The criteria used for selecting the 50 patients in this study were a history of digit sucking and an anterior dental open-bite. The sample consisted of Class I and Class II, Division 1 malocclusions, ages six through adult, for both sexes. If an individual was post— pubertal, they were classified as an adult. A Ricketts lateral cephalometric analysis of each patient was compared to standards of the same age. These differences were analyzed statistically with a Student t test and a one-way analysis of …

Effects Of Heat Treatment On The Mechanical Properties Of Chromium-Cobalt Alloy Wire, Robert L. Nations

Loma Linda University Electronic Theses, Dissertations & Projects

Since virtually all stages of orthodontic treatment involve forces obtained from deformed metallic materials, an understanding of properties of metals is an important part of orthodontics. The use of chromium-cobalt alloy for arch wires is relatively new to the field, and more needs to be known about its use in order to get the most from this product.

Many clinicians feel that advantages can be gained through a low temperature heat-treatment to change certain mechanical properties of the material. A tensile test was chosen in the attempt to learn more about this alloy in the untreated form as well as …

A Clinical Method For Predicting Orthodontic Band Sizes, Robert P. Mohr

Loma Linda University Electronic Theses, Dissertations & Projects

A correlation was established among the orthodontic band sizes in a given individual. The original sample contained 258 data sets (Unitek Corp. band sizes from first molar through the first molar in both arches) which were computer analyzed. The maxillary right central incisor band size was selected as the "predictor size" for a band size prediction table developed from this study.

An additional 56 data sets were tabulated and became the test sample to test the accuracy of the band size prediction table. Band sizes of the test sample were predicted within ±1 band size 66% of the time and …

Tensile Properties Of Stainless Steel Orthodontic Wire, Elbert E. Jackson

Loma Linda University Electronic Theses, Dissertations & Projects

Ten types of .020 inch stainless steel wire were compared using a tensile test. The wires were tested in the as-received condition and after heat treatment at 750°F for eleven minutes. The data were then analyzed statistically using the general linear hypothesis.

In the as-received condition each of four mechanical properties--elastic modulus, 0.2 per cent yield strength, tensile strength, and percent elongation--was found to vary significantly from one type to another.

When subjected to heat treatment, the elastic modulus proved to be the most stable of the four properties, changing only slightly in three cases. There was no significant change …