Thesis (M.S.)--University of Michigan, 2002. / Includes bibliographical references.

Thesis (M.S.)--University of Michigan, 1998. / Includes bibliographical references.

published_or_final_version / Dentistry / Master / Master of Dental Surgery

published_or_final_version / Dentistry / Master / Master of Dental Surgery

published_or_final_version / Dentistry / Master / Master of Dental Surgery

The controversy surrounding the role of malocclusion and orthodontic treatment in temporomandibular joint (TMJ) dysfunction led to this study. The purpose of this study was to establish the prevalence and compare the status of signs and symptoms of TMJ dysfunction in four groups of adolescents and young adults. The groups consisted of 14 persons with normal occlusions, 23 with untreated malocclusions, 20 with malocclusions currently undergoing treatment, and 18 with treated malocclusions. The Helkimo index was used to collect the TMJ dysfunction data. The results showed that the untreated malocclusion group had the most number of persons with signs and symptoms of dysfunction, but the differences between the groups in the distribution of persons according to the anamnestic and clinical dysfunction indices were not statistically significant. There were also no statistically significant differences in the distribution of signs and symptoms between boys and girls. According to anamnesis, the most frequently reported symptoms were joint sounds and headaches or neckaches occurring more than twice a week. Amongst the clinical signs and symptoms, the<br /> most commonly occurring were joint sounds on auscultation and muscle tenderness on palpation. In light of the small study sample and the absence of any substantial differences between the four groups, the role of malocclusion and orthodontic treatment in the aetiology of TMJ dysfunction remains obscure.

The development of a uniform method of epidemiological assessment and grading of malocclusion has been of interest for several decades. Recently, Daniels and Richmond (2000) proposed a new orthodontic index namely the Index of Complexity, Outcome and Need (ICON). Their aim was to develop a single index for assessing treatment inputs and outcomes.<br /> <br /> The aim of this study was to critique the ICON and to assess to the extent to which each component of the ICON fulfils the ideal requirements of the ideal index as identified in a World Health Organization Report (WHO, 1966). The study was performed in three parts: 1) a gold standard was established to test reliability and validity of the ICON / 2) to assess ease of use and simplicity of the index / 3) and to test the applicability of the index on patients and study casts. The results showed that the ICON identified 25% of the cases as &lsquo / no treatment&rsquo / , as apposed to the 100% of the gold standard. Validity of the index was shown to be &lsquo / poor&rsquo / for complexity (? = 0.2) and degree of improvement (? = 0.34) and &lsquo / excellent&rsquo / for outcome. Reliability was high for all the components except for treatment need (? = 0.63). This study concluded that except for complexity and degree of improvement, the index performed well with respects to reliability, validity (of treatment outcome), ease of use and simplicity and applicability to patient and study casts.

Thesis (M.Sc.D.)--Boston University School of Graduate Dentistry, 1972. (Periodontology) / Bibliography included.

Philosophiae Doctor - PhD / The aim of this project was to measure changes in dimension of the first three primary rugae and to evaluate tooth movement in the maxilla during orthodontic treatment in patients treated with and without premolar extractions. / South Africa

Aim This thesis has several aims;• to explore the available evidence surrounding interceptive orthodontics (IO), • to explore current general dental practice with regard to the provision of interceptive orthodontic care, and• to consider the way forward in the UK for providing simple interceptive orthodontic care for children in primary care. Methods Systematic reviews were conducted in areas where there had previously been no high quality reviews; interventions for the cessation of non-nutritive sucking habits (NNSH) in children, and correction of anterior crossbites in children. Semi-structured interviews were performed, transcribed, and thematic analysis performed, helping to develop a questionnaire. Following development, the questionnaire was posted to 400 General Dental Practitioners (GDPs) across Scotland. The results were analysed, and potential barriers to providing care were identified. A cost analysis was performed, using some of the data from the questionnaire to calculate the current cost to the NHS of managing children with persistent digit sucking habits. A sensitivity analysis was constructed to predict if a saving could be made to the NHS, if there was a change in clinical practice in primary care. Finally, a protocol for an interventional study was developed using the results from some of this work, to increase the provision of IO in primary care. Results The systematic review of interventions for NNSH identified 183 initial papers, which after checking for relevance and quality, were reduced to a final six RCTs which were included in the final review. The results suggested that a fixed habit breaker was the most effective intervention for digit suckers. The systematic review of correction of anterior crossbites in children identified 499 papers, which after checking for relevance and quality, were reduced to a final 46 studies which were included in the final review. The results suggested that anterior crossbites were best managed with a fixed “2 x 4” appliance. The interviews suggested confidence, and previous experience may play a role in determining whether a GDP will provide IO. The questionnaire highlighted that confidence, knowledge, and age could all be barriers to providing care, and these were the focus for the design of the intervention study. The cost analysis demonstrated that a potential saving of approximately £20,000 to NHS Tayside could be made by changing current practice from provision of a URA to a fixed habit breaker. If this change was implemented across Scotland this saving could increase to over £1,000,000. Larger savings could be made if less monitoring of the habit and more provision of fixed habit breakers was implemented (over £60,000 in NHS Tayside). Conclusions The systematic reviews highlighted the need for high quality studies in their subject areas. The cost analysis demonstrates the range in savings that could be made to the NHS depending on the changes made to current GDP practice. The interviews and questionnaire demonstrated there is scope to improve the provision of IO in primary care. The biggest barrier to providing IO appears to be confidence, specific to designing treatment plans, and how effectively the plan can be carried out for the patient. It is intended that the proposed investigation, outlined at the end of this thesis, to increase GDPs provision of IO, will be conducted. If the intervention proves successful, it could be rolled out across the UK, changing current clinical practice.