Medicine and Health Sciences Commons^™

Changes In Pharyngeal Airway Dimensions Due To Mara Treatment In Class Ii Malocclusions, James K. Dillehay

Theses and Dissertations (ETD)

Orthodontic treatment effects on the pharyngeal airway have recently become a hot topic in the field of orthodontics. Current literature has shown facial skeletal morphology to be correlated with pharyngeal airway shape and volume. This study used CBCT imaging to identify what, if any, effects two different treatment modalities for correcting Class II malocclusions have on the pharyngeal airway volume. This retrospective study consisted of two groups of Class II patients: 38 patients (15 females, 23 males) treated with the MARA and an Edgewise appliance and 32 patients treated with an Edgewise appliance and Class II elastics. Both pre and …

Treatment Effects Of The Mandibular Anterior Repositioning Appliance (Mara) And Conventional Orthodontic Mechanics On Temporomandibular Joint Morphology: A Comparison Using Cone Beam Computed Tomography, Brenton E. Glassell

Theses and Dissertations (ETD)

Introduction: An ongoing debate exists in orthodontics about the amount of condylefossa remodeling and growth seen in Class II patients using functional appliance therapy. Some clinicians and researchers have found that that the use of functional appliances increases the amount of condylar growth and subsequent Class II skeletal correction; others believe that the mandible has a preset amount of growth and that conventional orthodontics will result in a similar amount of condylar growth to functional appliance therapy. Purpose: The aim of this study was to compare condylar remodeling in functional appliance treatment using the mandibular anterior repositioning appliance (MARA) to …

Rankl And Osteoprotegerin Levels In Response To Orthodontic Forces, Katherine Ann Hart D.D.S.

Theses and Dissertations (ETD)

Orthodontic tooth movement is mediated by interactions between PDL cells and those of the alveolus. One protein—the receptor activator nuclear factor kappa B ligand (RANKL)—is critical for osteoclastogenesis, and osteoprotegerin (OPG) is a decoy ligand that competitively inhibits RANKL. A higher RANKL/OPG ratio is associated with areas of bone resorption, while a lower ratio occurs in areas of bone deposition and homeostasis. There have been almost no clinical studies of RANKL and OPG expression in human subjects undergoing orthodontic tooth movement. The purpose of this study was to quantify changes in the levels of RANKL and of OPG expression in …

A Secular Increase In The Tempos Of Tooth Formation: 1980-2010, Kevan Michael O'Neill

Theses and Dissertations (ETD)

Introduction: Improved environments in the U.S. have resulted in taller, larger, and heavier children and adults compared to past generations. Studies of other skeletal-dental dimensions have shown increases across generations, and our perception is that teeth now are forming faster. The purpose of this study is to test for a secular trend towards faster tempos of tooth mineralization in a sample of U.S. white adolescents over the past quarter century (1980-85 to 2005-10).

Materials: Two cohorts of 200 children each were identified, each with an age range of 10-to- 15 years, one group from 1980-85 and the more recent group …

Skeletal And Dental Components Of Class Ii Division 1 Correction With The Mara Compared To The Standard Edgewise Appliance, Zachary Paul Pitcher

Theses and Dissertations (ETD)

Many tools are available to correct Class II dental relationships. A functional orthopedic appliance is a popular type of Class II corrector that is thought to correct Class II dental relationships both dentally and skeletally by enhancing mandibular growth. The purpose of the study was to quantify differences in the amounts of skeletodental change based on treatment (MARA and Standard Edgewise) in Class II Division 1 patients. The sample consisted of 2 groups of Class II Division 1 patients: 51 patients treated with the MARA followed by an Edgewise appliance and another group of 51 patients treated with the Standard …

Oropharyngeal Airway Volume Following Orthodontic Treatment: Premolar Extraction Versus Non-Extraction, Thomas Patrick Shannon

Theses and Dissertations (ETD)

Orthodontic correction of tooth size versus arch size discrepancy (TSASD) can be achieved with two distinct methods of treatment. The first involves the extraction of teeth to gain the space needed for tooth alignment. The second relies on arch expansion to gain the space needed for correction. In recent decades, arguments for and against the extraction of teeth for orthodontic purposes have become increasingly important, particularly in regards to oropharyngeal airway size. Purpose: The purpose of this study is to determine whether there is a decrease in oropharyngeal dimensions following the extraction of four premolars and subsequent orthodontic therapy. Methods: …

Oropharyngeal Airway Volume Following Orthodontic Treatment: Premolar Extraction Versus Non-Extraction, Thomas Patrick Shannon

Theses and Dissertations (ETD)

Orthodontic correction of tooth size versus arch size discrepancy (TSASD) can be achieved with two distinct methods of treatment. The first involves the extraction of teeth to gain the space needed for tooth alignment. The second relies on arch expansion to gain the space needed for correction. In recent decades, arguments for and against the extraction of teeth for orthodontic purposes have become increasingly important, particularly in regards to oropharyngeal airway size. Purpose: The purpose of this study is to determine whether there is a decrease in oropharyngeal dimensions following the extraction of four premolars and subsequent orthodontic therapy. Methods: …

Efficacy Of Temporary Fixed Retention Following Comprehensive Orthodontic Treatment, Mark J. Owens

Theses and Dissertations (ETD)

Instability of the occlusion is a common problem following orthodontic treatment. The purpose of the present research was to evaluate posttreatment relapse at long-term recall (> 10 years) in cases (A) treated with temporary fixed mandibular retention plus Hawley retainers compared to (B) a similar group retained with just removable retention (standard Hawley type retainers alone). Fixed retainers were removed after having been in place for about 2.5 years. Following this period, use of removable retention was left up to the discretion of the patient in both groups. Data consisted of orthodontic records of 166 American whites, all of whom …

The Long-Term Stability Of Class Ii Cases Treated In A Private Practice Using A Straightwire Appliance: A Dental Cast Analysis, Lina K. Kulkarni

Theses and Dissertations (ETD)

Achieving long-term stability after orthodontic treatment is a major challenge for orthodontists. The previous literature shows that relapse occurs at a considerable magnitude. The purpose of the present study was to determine the amount and type of long-term, posttreatment relapse that occurs in a homogeneous group of patients treated by a single experienced orthodontist in a private practice setting. Dental casts from a sample of 30 Class II division 1 Caucasian females treated without extractions were evaluated at pretreatment (mean age = 13.1 years), posttreatment (mean age = 15.9 years) and recall (mean age = 28.3 years) to determine the …

Craniofacial Changes Following Nonextraction Orthodontic Treatment: A Long-Term Cephalometric Analysis, James Austin Rahaim

Theses and Dissertations (ETD)

Long-term posttreatment cephalometric changes from late adolescence into early adulthood were analyzed in this study. Lateral cephalometric radiographs from a sample of 30 Class II division 1 Caucasian females treated without extractions were evaluated at posttreatment (mean age = 15.9 years) and recall (mean age = 28.3 years). All of the subjects were treated in the private practice of a single, experienced practitioner. The cephalograms were examined to investigate changes in the cranial base, midface, maxilla, mandible, maxillomandibular relationships, dental relationships, and the soft tissue profile that occurred at an average of 12.4 years posttreatment. Descriptive and inferential statistics were …

A Survey Of Treatment Characteristics In A University-Based Graduate Orthodontic Program, A. Brian Anderson

Theses and Dissertations (ETD)

While there are a few national surveys on malocclusion in the U.S., few reports characterize actual orthodontic patients and their treatments. The purpose of this study was to describe the patients and their treatment at a university based orthodontic department, namely the University of Tennessee Health Science Center, Memphis. The goals of this study are: (1) to research patient demographics, dental and skeletal relationships and treatment variables; (2) to test for temporal trends in these patients and their treatment across a 26 year interval from 1980 to 2005; and (3) to assess the correlations among patient demographics, dental and skeletal …

Long-Term Changes In The Dental Occlusion Of Subjects Treated Orthodontically, Kenneth Cooper Dyer Iv

Theses and Dissertations (ETD)

A major challenge in orthodontics is to provide a treatment result that remains stable after appliances are removed. Orthodontic treatment can move teeth from their neutral positions, which increases potential for future relapse. The literature from the University of Washington, Seattle, shows that relapse is pervasive and of considerable magnitude (Little RM. Stability and relapse of mandibular anterior alignment: University of Washington studies. Semin Orthod 1999;5:191-204). The intent of this study was to quantify the posttreatment dental changes that occurred over approximately a quarter-century in a cohort of women who had received comprehensive orthodontic treatment as teenagers. Dental casts of …

Modulation Of Rankl And Osteoprotegerin In Adolescents Using Orthodontic Forces, Nathan Reed Hamman

Theses and Dissertations (ETD)

Orthodontic tooth movement is mediated by interactions between PDL cells and those of the alveolus. One protein--the receptor activator nuclear factor kappa B ligand (RANKL)--is critical for osteoclastogenesis, and osteoprotegerin (OPG) is a decoy ligand that competitively inhibits RANKL. A higher RANKL/OPG ratio is associated with areas of bone resorption, while a lower ratio occurs in areas of bone deposition and homeostasis. There has been almost no clinical study of RANKL and OPG expression in patients undergoing orthodontic tooth movement.

The purpose of this study was to quantify changes in the levels of RANKL and of OPG in response to …

Longitudinal Cephalometric Changes Of Orthodontic Patients Evaluated Long-Term, Lisa Ku

Theses and Dissertations (ETD)

Posttreatment changes are further complicated by the slow continued growth that occurs after treatment into adulthood. The purpose of this study was to examine long term posttreatment changes. The lateral cephalograms of 51 Caucasian females treated in the standard Edgewise practice of one private practitioner in Cookeville, TN were examined to investigate changes in the cranial base, nasomaxillary complex, mandible, interach relationships, dental relationships, and the soft tissue integumental profile that occured an average of 23 years posttreatment. Two tailed t-tests (α = 0.05) were run to see whether the posttreatment changes was statistically significantly different from zero. Craniofacial growth …

Cephalometric Evaluation Of Mara Therapy In The Treatment Of Class Ii Malocclusions, Tiffany Rachelle Mcclaran

Theses and Dissertations (ETD)

The effectiveness of functional appliances is a debatable topic in the orthodontic literature, primarily because the benefits have not been consistently reproduced among clinical studies. The present study was a retrospective cephalometric analysis of patients with Class II, division 1 malocclusions at the start of treatment. There were 51 children treated by a single clinician with a MARA in combination with Edgewise appliances. The comparison group consisted of subjects treated with fixed Edgewise appliances only from the University of Tennessee, Department of Orthodontics. Subjects in the two treatment groups were matched on a one-to-one basis for sex and for five …

Use Of Cvm Stages In Assessment Of Young Orthodontic Patients To Estimate Growth Potential, David Justin Sander

Theses and Dissertations (ETD)

Harnessing a patient’s growth to correct parasagittal discrepancies is an important part of Class II correction in orthodontic treatment; however, orthodontists rarely have the opportunity to choose when a patient is referred to them. Diagnostic records can assist the orthodontist in determining how much growth a patient has remaining. The purpose of this retrospective cephalometric study was to determine whether the amounts of in-treatment facial growth differ significantly by sex and by cervical vertebral maturation (CVM) stage. The sample consisted of 133 Class II division 1 patients from a single private practice office treated with a combination of a functional …

Mesiodistal Crown Size In Relation To The Risk And Severity Of Malocclusion, Jon Robert Zang-Bodis

Theses and Dissertations (ETD)

From among numerous potential causes of dental malocclusion, tooth size has been implicated as one factor. Prior studies show that mesiodistally larger teeth increase the risk of malocclusion. The present report extends our understanding by testing for graded responses between crown size and the extent of dental malocclusion. Maximum mesiodistal crown dimensions of all 14 permanent tooth types (excluding third molars) were measured in 207 American white adolescents (routine orthodontic patients), and 10 measures of malocclusion (e.g., rotations, displacements, spacing) were recorded. Analysis of covariance (controlling for sexual dimorphism in tooth size) disclosed (1) significant positive associations between …

Influence Of Tooth Crown Size On Malocclusion, Michael Kelly Agenter

Theses and Dissertations (ETD)

Malocclusion is an increasingly common, multifactorial problem in industrialized countries. Although the causes of dental malocclusion are obscure in most instances, one contributing factor may be tooth size. While several researchers have studied whether tooth size contributes to malocclusion, there still is no consensus. Some have found that the mesiodistal widths of the mandibular incisor teeth are significantly larger in subjects with anterior crowding, while others have been unable to support this conclusion. Study designs often have been confounded by combining the sexes, which confuses sexual dimorphism with the supposed effect of tooth size on crowding. The present study tested …

Esthetic Evaluation Of Edgewise Orthodontic Treatment In Matched Class Ii, Division 1 Subjects, With And Without A Mara, Kelly-Gwynne Mason Fergus

Theses and Dissertations (ETD)

Orthodontics’ concern about facial esthetics has motivated the investigation of treatment options, and their effects, in hopes of discerning the optimal treatment for patients, both esthetically and functionally. In our efforts to determine the optimal treatment option for patients with Class II, division 1 malocclusions, we examined two current treatment methods’ effects on facial esthetics, namely (1) orthopedic functional therapy using a MARA in combination with Edgewise appliances and (2) Edgewise mechanics alone. This study was a retrospective esthetic evaluation of profile silhouettes (prior to and following orthodontic treatment) of 30 consecutively treated American white adolescents with Class II, division …

Maxillary Incisor Crown Form And Crowding In Adolescent Orthodontic Patients, Kortne King Frederick

Theses and Dissertations (ETD)

Dental crowding occurs when the mesiodistal tooth crown widths exceed the space available in the dental arch for proper alignment. Previous research dealing with this common orthodontic problem has measured mesiodistal (MD) tooth widths or clinical tooth height-to-width ratios from dental casts. The present study used full mouth periapical series of dental radiographs, which provided an opportunity to study anatomical crown form of the maxillary incisors, as measured from the cementoenamel junction (CEJ), in relation to crowding. The aim of this study was to evaluate the statistical association between maxillary incisor crown form and the extent of crowding in adolescent …

Cephalometric Evaluation Of Bionator Therapy In The Early Treatment Of Class Ii Malocclusions, Daniel C. Sawrie

Theses and Dissertations (ETD)

Early or two-phase orthodontic treatment of Class II malocclusions is a debated topic in orthodontic circles primarily because the benefits of early intervention have not been consistently reproduced among researchers. The present study was a retrospective analysis of cephalograms from patients with Class II, division 1 malocclusions at the start of treatment. These were 50 consecutively treated youths who received phase 1 (early) treatment with a Bionator appliance and later treatment with full appliances (all treated by a single clinician). The comparison group consisted subjects treated in a single phase with fixed Edgewise appliances only. Importantly, subjects in the two …

Quantitative Analysis Of First- Versus Second-Premolar Extraction Effects In Orthodontic Treatment, Robert A. Turner

Theses and Dissertations (ETD)

Malocclusions can involve arch-size tooth-size discrepancies that have to be resolved by premolar extractions. Treatment planning in such cases usually involves removing first (P1) or second premolars (P2). Choosing an extraction pattern is a learned skill that incorporates many diagnostic factors. This study compared the amounts of in-treatment tooth movement in two common extraction patterns (4/4 and 5/5) in order to gain insight into the criteria used for differential diagnosis and treatment planning. Objective: A method of cast analysis was developed to measure the anteroposterior and transverse changes in tooth positions during orthodontic treatment. Data were used (1) to …

Cephalometric Evaluation Of One-Phase And Two-Phase Treatment Alternatives In Matched Class Ii Subjects, Fredrick Jerome Burr

Theses and Dissertations (ETD)

“Early” or two-phase orthodontic treatment of Class II malocclusions is a highly debated topic in the orthodontic literature. We report here on a retrospective cephalometric study of patients with Class II, division 1 malocclusions. One group consisted of 32 consecutively treated patients who received “early” treatment with a Fränkel II appliance followed by treatment with full fixed appliance. These subjects were “matched” by sex and cephalometric value, to a subject treated with standard edgewise appliances in a single phase. Matching criteria focused on the bony facial characteristics, notably ANB, NAP, Y Axis, AOBO, FMA, overjet, and overbite. The question was …

Root Morphology And Sexual Dimorphism : Size Standards For Crown And Root Dimensions In Adolescents, William Max Couch

Theses and Dissertations (ETD)

“Early” or two-phase orthodontic treatment of Class II malocclusions is a highly debated topic in the orthodontic literature. We report here on a retrospective cephalometric study of patients with Class II, division 1 malocclusions. One group consisted of 32 consecutively treated patients who received “early” treatment with a Fränkel II appliance followed by treatment with full fixed appliance. These subjects were “matched” by sex and cephalometric value, to a subject treated with standard edgewise appliances in a single phase. Matching criteria focused on the bony facial characteristics, notably ANB, NAP, Y Axis, AOBO, FMA, overjet, and overbite. The question was …

Dependence Of Craniofacial Growth On Stages Of Cervical Vertebral Maturation And Stages Of Mandibular Canine Mineralization, Charles Allen Chance

Theses and Dissertations (ETD)

When an individual presents for orthodontic treatment, orthodontic records are made that also include demographic information. The orthodontic treatment plan is determined not only from the diagnostic records but also from the relative amounts of growth the orthodontist perceives will take place during treatment. The purpose of this study was to determine if pretreatment biological age, as assessed from cervical vertebral (CV) maturity and/or mandibular canine mineralization, are statistically tied to the amount of growth occurring during treatment, and if so, then if biological age has any predictive merit in anticipating the amounts of growth occurring during treatment. The sample …

Changes In Integumental Dimensions Of The Face Following Orthodontic Treatment: A Long-Term Study, Jack Hou

Theses and Dissertations (ETD)

Most studies of facial growth in adults have relied on cross-sectional data. Longitudinal studies in this area are scarce because it is difficult to collect data on adults across time and because the changes are less dramatic than during childhood or adolescence. An interesting sample exists in the Charles H. Tweed collection, where orthodontic patients were recalled 10 or more years after treatment with an average time out of treatment of about 15 years. The availability of frontal facial photographs from this collection provided us with an uncommon opportunity to longitudinally quantify the changes in facial dimensions from adolescence into …

Dental Maturation In Children Treated For Acute Lymphocytic Leukemia, Michael Grey Weathersby

Theses and Dissertations (ETD)

Acute lymphocytic leukemia (ALL) is a life-threatening disease primarily affecting children. Treatment currently consists of chemotherapy sometimes in combination with head irradiation. The literature documents the damage of treatment to the teeth (e.g., congenital absence, microdontia, abnormal crown- root ratios). The present study assessed the effects of treatment for ALL on the tempos of dental maturation (i.e., dental age) in a mixed longitudinal sample of 72 children treated for ALL at St Jude's Children's' Research Hospital, Memphis, Tennessee. Panoramic radiographs had been taken as indicated to assess and maintain dental health in this retrospective study. Dental age was quantified both …

First Premolar Extraction Decisions And Effects, Ryan Gregory Bowles

Theses and Dissertations (ETD)

The most common method of resolving substantial tooth size-arch length discrepancies (TSALD) is to treat patients with the extraction of premolars. Not all of the extraction space, however, is needed to eliminate the patient's TSALD. Also, it is typical that some of the extraction space will be lost because the molars are used as anchorage units to retract the anterior teeth. OBJECTIVE: This study developed a method to measure changes in the positions of the canines and second premolars relative to the palatal rugae. These data were used to assess how the extraction space was used in resolving the malocclusion. …

Effects Of Sickle Cell Disease On Growth Of The Craniofacial Complexes, Timothy Charles Bandeen

Theses and Dissertations (ETD)

Sickle cell disease (SCD) is a genetic disorder affecting over 100,000 African Americans. While once lethal, medical treatment now allows those with SCD to lead comparatively normal lives, and these children are more frequently seeking orthodontic treatment. We report here on a cephalometric study of a contemporary cohort of 62 children with SCD (27 SC and 35 SS genotypes). This was a cross-sectional study of children from the MidSouth between 3 and 16 years of age, and results were co mpared to standards in Richardson’s Atlas of growth of American Black children in Nashville, TN. Raw values were converted to …

Root Surface Area Related To Anchorage In The Begg Technique, Donald Copeland Freeman

Theses and Dissertations (ETD)

Almost two hundred years ago Hunter recognized the necessity of extracting teeth to ’’procure room for the others which are to be brought into the arch.” He further noted that, ”To extract an irregular tooth would answer but little purpose if no alteration could be made in the situation of the rest.”¹

Extraction of selected teeth to gain room for the proper placement of the rest, and the subsequent procedures to utilize this space to the utmost advantage, have been integral parts of orthodontic treatment for many years.

Strang and Thompson² stated that the ability to manipulate any …