Objectives: 1) To develop and investigate the bioactivities of a novel bioactive glass (BAG) composite designed as an orthodontic adhesive. 2) To investigate the preventive effect, and to test the bond strength of the adhesive. Methods: A novel, calcium and phosphate rich, and fluoride containing, bioactive glass (BAG) was prepared via the melt quench route and incorporated into an experimental resin to produce a light cured paste. The ratio of the resin to the powder was 20:80% respectively. The BAG powder was gradually replaced by a high fluoride and silica content glass (HSG) from 80%, to 60%, 50%, 40%, 25% and 0%. 90 disks (1.26mm thickness and 10mm diameter) were produced from each composition to be immersed in 3 solutions (demineralising artificial saliva pH=4 (AS4), remineralising artificial saliva pH=7 (AS7) and Tris buffer (TB) pH=7.3, 10 ml each. Measurements were taken at 10 time points (from 6 hours to 6 months) in 3 replicas in each solution. Ion release study was determined by ISE and ICP, and pH monitoring was conducted on the resulting solutions. Immersed disks were studied by FTIR, XRD, MAS-NMR and SEM for apatite formation. XMT were used to study the effects of this material on demineralisation/remineralisation in human enamel. Shear bond strength of the adhesive on bovine enamel were studied in different conditions using an Instron machine. Results: The pH increased with time for all the samples with BAG in all solutions and was linearly correlated to BAG loading. Ion release results revealed that the composite disks release up to 15ppm F-, 450ppm Ca2+ and 10ppm PO43- ions, and the release pattern is directly related to the immersion time, with the highest release found in AS4. FTIR spectra, XRD patterns and SEM images showed formation of apatite on all the BAG-resin disks, especially in AS4 and this increase with time. The MAS-NMR spectra indicated fluorapatite was also formed. The XMT studies showed that the novel material reduces demineralisation around the brackets by 80%. The shear bond strength of this novel material was comparable to that of Transbond XT. Conclusion: The novel BAG composites have significant long term releases of F-, Ca2+ and PO43- ions, especially in acidic conditions and form apatite (including FAP) in acidic and neutral solutions. This implies that the material has the potential as an orthodontic adhesive that can prevent white spot lesions around brackets.

A proposta deste trabalho foi avaliar em pacientes portadores de Periodontite Agressiva (PA) os parâmetros clínicos periodontais antes da movimentação ortodôntica, imediatamente após seu término e quatro meses após seu término. Participaram do estudo vinte pacientes dos gêneros masculino e feminino, não fumantes, divididos em dois grupos (Grupo Teste -10 pacientes portadores de PA; Grupo Controle 10 pacientes periodontalmente saudáveis). Todos pacientes receberam movimentação ortodôntica sob rigoroso controle mecânico do biofilme realizado bimestralmente durante todo o tratamento ortodôntico. Foram avaliados os seguintes parâmetros clínicos: profundidade clínica de sondagem, junção esmalte cemento margem gengival, nível clinico de inserção, sangramento a sondagem e índice de placa bacteriana. Estes parâmetros foram mensurados por um único examinador cegado e calibrado, em três momentos (pré-ortodontia; pós-ortodontia; pós 4 meses da ortodontia) Após análise estatística (p<0,05), houve redução significativa para SS e IP apenas para o grupo teste. Na medição de 4 meses após ortodontia, os pacientes do grupo teste apresentaram melhoras significativas para os parâmetros PCS, JEC-MG e NCI. No grupo controle, a melhora estatisticamente significativa somente não ocorreu no parâmetro JEC-MG. Para ambos os grupos, nos molares, observamos melhora significativa do NCI em função da redução da PCS. Nos pré molares o mesmo ocorreu, porém, somente para o grupo teste. Nos caninos não foram observadas alterações para nenhum parâmetro em nenhum dos grupos. Nos incisivos houve melhora estatisticamente significativa no NCI, em função da melhora do parâmetro JEC-MG. Esta melhora ocorreu somente no grupo teste. Frente à metodologia empregada neste trabalho, podemos concluir que a movimentação ortodôntica em pacientes portadores de Periodontite Agressiva é possível e que não altera clinicamente os parâmetros clínicos periodontais desde que exista um ótimo controle do biofilme bacteriano e ausência dos sinais clínicos de inflamação. / The aim of this research was to evaluate periodontal clinical parameters in orthodontically treated patients with aggressive periodontitis. Twenty subjects of both genders, non-smokers, where divided in group Test (10 patients with aggressive periodontitis) and control (10 periodontally healthy subjects). All individuals were submitted to orthodontic treatment, under strict biofilm control every 2 months during the entire duration of the treatment. The following clinical paramenters were assessed: pocket depth; gingival recession, clinical attachment level, bleeding on probing and dental plaque index. All clinical parameters were monitored before orthodontic treatment (baseline), immediately after the completion of the orthodontic movimentation, and 4 months post-treatment by a masked calibrated single examiner. Statistical analysis disclosed a significant (p<0,05) reduction of bleeding on probing and plaque index for the test group only. The overall probing depth, gingival recession and attachment level improved for the test group at the 4 months post-treatment examination. For the control group the only parameter which did not show any improvement was the gingival recession. In both groups there was a significant improvement in the clinical attachment level due to the reduction in pocket depth, for the molar teeth. The same improvement was observed in the bicuspids, but only in the test group. There were no changes in any of the paramenters for the cuspids, both for the test and the control subjects. The incisors presented a statistically significant improvement in the clinical attachment level, due to an improvement in the gingival recession paramenter. This improvement was only observed in the test group as well. In light of the above, it was concluded that orthodontic movement in aggressive periodontitis patients is not only possible, but it is not harmfull for the periodontium as long as there is an optimal dental plaque control and an absence of clinical signs of inflammation.

Magister Scientiae Dentium - MSc(Dent) / In modern day dentistry, aesthetics forms an integral part of our social perception almost as much as functionality. Malocclusion has been brought to the forefront of developmental anomalies as it can affect mastication, speech as well as the appearance of the face. Furthermore, pre-pubertal and pubertal changes have compounded existing malocclusions in this growth period thus spiraling the need for orthodontic treatment. Therefore, it is essential to determine the normative and selfperceived need for orthodontic treatment in a population. The epidemiological data collected can be used to facilitate policy changes to manage malocclusion in Khomas, Namibia. Aim: The aim of this study was to determine the orthodontic treatment needs of a population of 12-15 year-old children attending a school in Khomas and to express it as percentages of those with subjective and objective orthodontic treatment need over the whole sample population. The objectives were to find associations between treatment needs and some demographic and socioeconomic factors.

Magister Scientiae Dentium - MSc(Dent) / Influence of orthodontic caregiver behaviour on the perceived satisfaction of patients during orthodontic treatment. Dr. F.J. du Raan M.Sc. (Orthodontics) thesis, Department of Orthodontics, University of the Western Cape. In this thesis I interviewed patients that are busy with orthodontic treatment, as well as those that have undergone orthodontic treatment at the department of Orthodontics at the University of the Western Cape, with the aid of four questionnaires. Patients completed questionnaires to provide general and demographic information, quantify their satisfaction with the orthodontic treatment process, their perception of the orthodontic clinician's behavioural traits and lastly they completed the NEO-FFI personality questionnaire to determine their own personality profile. All these questionnaires were used in previous studies, or they were slightly modified to be applicable to orthodontics. The information gained was used to determine if there are correlations between the patient’s perceived satisfaction of the treatment process with patient specific treatment variables (as acquired from the General information and Demographics Questionnaire ), demographic factors, clinician's behavioural traits and patient specific personality traits and any combination of the above mentioned. We wanted to determine which behavioural traits of the orthodontic caregiver influences the perceived satisfaction with the treatment to the greatest extent. Furthermore, we wanted to determine if certain personality traits of the patients would influence their perceived satisfaction with the treatment process or their perception of the clinician's behavioural traits. The only aspect from the General Information and Demographics Questionnaire that had any correlation to satisfaction with the treatment process or the perception of the clinician's behavioural traits, was whether the patient was treated by a single registrar or multiple registrars. Patients treated by multiple clinicians had a lower average score for satisfaction and orthodontist behaviour. Results from the study shows that all the clinician's behavioural traits do have statistically significant influence on the perceived satisfaction with the treatment process, but certain behavioural traits have a greater influence. Result showed Empathy and Care to have the strongest influence on perceived satisfaction, whereas Motivation has the lowest influence. The NEO-FFI personality questionnaire was used to register each patient's personality profile. Scoring for the following personality traits created the personality profile: Neuroticism, Extraversion, and Openness to Experience, Conscientiousness and Agreeableness. Patient personality profiles were shown to have no significant influence on the patient's perceived satisfaction with the treatment process.Neuroticism was shown to have a weak negative correlation with the Professionalism sub-category of the Orthodontic Clinician Behaviour Questionnaire. Conscientiousness has been shown to have a weak positive correlation with all categories of the Orthodontic Clinician Behaviour Questionnaire It is put forth by the researcher that more time and effort has to be put into improving all aspects of the clinician's behaviour, as it will positively influence the perceived satisfaction of the orthodontic treatment process.Even though there are no significant correlations, patients needs to be screened to determine their personality profiles, as this may lead to slight improved scoring on certain behavioural aspects which may in turn lead to greater patient satisfaction. It may be especially worthwhile to recognise the neurotic patient and treat them on a more personal level, as this may improve their overall satisfaction.

Magister Scientiae Dentium - MSc(Dent) / Introduction: Improvement of aesthetics is often the reason patients seek orthodontic treatment. The ability to accurately assess aesthetic treatment need from the viewpoint of the patient is necessary. The threshold for orthodontic treatment is not constant in all countries and no previous attempts to determine this threshold has been made in South Africa. By ensuring that patient’s perceptions of treatment need are incorporated into the index chosen to assess perceived need, accurate data can be obtained. Determining perceived need from the patient’s viewpoint is important, and understanding its relationship with perceived need according to the professional, as well as normative need can facilitate better patient communication and management of expectations. Aims: There were three main aims of this study. First, South African children’s perceptions of treatment need according to the Aesthetic Component (AC) of the Index of Orthodontic Treatment Need (IOTN) was assessed to determine if they were similar to those of the dentists who established the threshold, or if the threshold of the grading system should be altered to better suit laypeople’s opinions. Second, the newly established threshold could then be used to determine the perceived needs for orthodontic treatment, and compare them to the normative need of the population. Finally, factors that may influence the perceived needs of the patients such as gender, ethnicity and socio-economic position could be investigated. Methodology: A cross-sectional study on 317 children aged between 11 and 14 years was done. 43.8% were male and 56.2 % were female. The sample was chosen from five schools in the Lekwa District of Mpumalanga using a multi-stage sampling technique. The study population comprised of four groups based on ethnicity; Asian (3%), black (74%), coloured (6%) and white (17%). The socio-economic position (SEP) was determined by Principal Component Analysis of household assets. Societal perceived, subjective perceived and self-perceived needs were assessed using a questionnaire and the child-rated AC of the IOTN. An intra-oral examination was conducted using the AC of the IOTN to assess objective perceived need and the modified Dental Health Component (DHC) of the IOTN to assess normative treatment need. Results: Treatment threshold was determined to be grade 3 of the AC of the IOTN according to societal perceived need of the group of South African children, and was confirmed by self-perceived need. Subjective perceived need for treatment was assessed using the AC grade participants felt best reflected their aesthetic impairment, and was found to be 20.2%, compared to actual self-perceived need of 38.5%. The latter was deduced by comparing the child-rated AC (subjective perceived need) to their perception of treatment need of that grade (societal perceived need). The objective perceived need measured by the examiner-rated AC was 60%. Definite need for orthodontic treatment based on the modified DHC of the IOTN was 41.2%. No significant difference between societal perceived or self-perceived need and gender or socio-economic position was found. White children have lower societal perceived treatment need regarding others’ aesthetic impairment. Conclusion: The treatment threshold grade should be lowered to better represent the societal perceived and self-perceived need of the South African population. Normative need was higher than perceived needs from the patients’ point of view (subjective perceived and self-perceived need), but lower than the perceived need from the professional’s point of view (objective perceived need). Ethnicity was found to have an influence on societal perceived need.

Nos tratamentos ortodônticos, fios de diferentes ligas metálicas são utilizados nas etapas de alinhamento, nivelamento, correção da posição molar, fechamento espacial, acabamento e retenção. Com relação às duas últimas, responsáveis pelo posicionamento adequado dos dentes superiores sobre os inferiores, a preparação requer um fio que favoreça o torque de incisão, ou seja, que apresente grande resistência e rigidez associadas à ativação de pequeno alcance. Para este fim, os fios de aços inoxidáveis austeníticos retangulares são os preferidos em razão do módulo de elasticidade elevado e boa resistência à corrosão no meio bucal. Quanto à geometria retangular, o processo de fabricação requer desenvolvimento tecnológico adequado para a produção em escala industrial de fios com as características geométricas e propriedades mecânicas para melhor adequação às necessidades de uso. Com o objetivo de se produzir fios com tais características, foi desenvolvido um laminador para a fabricação de fios retangulares com a intuito de se dispor de uma alternativa de menor custo ao processo de produção por trefilação, de custo elevado, devido a complexidade das matrizes. Além da fabricação do laminador, foram avaliados os aspectos tecnológicos que envolveram os efeitos da deformação nas propriedades mecânicas dos fios, por meio de medidas de microdurezas e ensaios em tração e de flexão. Nos testes realizados, os fios apresentaram geometria, acabamento superficial e propriedades mecânicas adequadas à sua utilização em tratamentos ortodônticos. / In orthodontic treatments, wires of different metallic alloys are used for alignment, leveling, correction of the molar position, space closing, finish and retention. With respect to finish and retention, these wires are responsible for adequate positioning of the upper teeth on the lower teeth. Wires that are subjected to incisor torque require high resistance and stiffness. For this, wires of rectangular austenitic stainless steel are used due to high modulus of elasticity and good corrosion resistance in the oral environment. Because of the rectangular geometry, wire production requires process development suitable for industrial scale manufacture with geometric characteristics and mechanical properties better adapted to the use conditions. To obtain wires with such characteristics, a rolling mill was developed for the production of rectangular wires by a rolling process with the objective of reducing cost of the cold drawing process that is currently used, which utilize complex and expensive wiredrawing dies. In addition to the rolling process itself, wire deformation, microhardness, tension and bend tests were also performed. In these tests, wire geometry, surface finish and mechanical properties were successfully adapted for use in orthodontic treatments.

La ortodoncia osteogénica periodontalmente acelerada es un procedimiento indicado para minimizar el tiempo de tratamiento ortodóncico brindando una alternativa de tratamiento a pacientes periodontalmente comprometidos, con presencia de reabsorciones radiculares, periodonto reducido, entre otros. Los problemas periodontales no diagnosticados pueden ser agravados durante el tratamiento ortodóncico y dependiendo de su severidad, pueden requerir un tratamiento previo. El objetivo de este reporte es presentar el caso de una paciente con maloclusión Clase I con apiñamiento y recesión gingival, tratada con injerto conectivo de tejido libre, corticotomía con injerto óseo y técnica de arco recto prescripción CCO. Finalmente, se puede concluir que el manejo interdisciplinario es importante para el correcto diagnóstico y tratamiento de los pacientes. La ortodoncia osteogénica periodontalmente acelerada es una alternativa viable que reduce el tiempo de tratamiento ortodóncico y mantiene o mejorá la condición periodontal de los pacientes. / Periodontally accelerated osteogenic orthodontics is a procedure indicated to reduce the time of orthodontic treatment by giving an alternative treatment to periodontally compromised patients, with presence of root resorption, reduced periodontium, among others. Undiagnosed periodontal problems can be aggravated during orthodontic treatment and, depending on their severity, may require prior treatment. The objective of this report is to present the case of a patient with Class I malocclusion with crowding and gingival recession, treated with free tissue connective graft, corticotomy with bone graft and CCO Straighwire prescription technique. Finally, it can be concluded that interdisciplinary management is important for the correct diagnosis and treatment of patients. Periodontally accelerated osteogenic orthodontics is a viable alternative that reduces the time of orthodontic treatment and maintains or improves the periodontal condition of patients. / Tesis

OBJECTIVES: To compare the amount of fluoride, calcium and phosphate release and recharge of a fluoride containing bioactive glass composite to a conventional resin composite and a resin modified glass ionomer cement at different time points. Furthermore, bond strength of a fluoride containing bioactive glass composite, a conventional flowable composite, and a resin modified glass ionomer cement to metal orthodontic brackets was evaluated. METHODS: A fluoride containing bioactive glass (BG) was synthesized using a sol-gel method and mixed homogeneously with an unfilled resin. For ion release and recharge, resin modified glass ionomer (RMGIC), Photac Fil Quick Aplicap (3M/ESPE) and flowable composite (Control), Filtek Supreme Ultra (Kerr), were used for comparison. Disc shape samples were fabricated using custom aluminum mold (1 mm in thickness and 9 mm in diameter, (n=5 for each material) and stored in 15 mL deionized water at 37°C until the testing time. The amounts of fluoride, calcium, and phosphate ions released were evaluated at different time points: 1 hour, 24 hours, 2 days, 3 days, 4 days, 5 days 6 days and 7 days. At each time point, all of the storage solution was extracted, and 7.5 mL was used for fluoride release measurement and the remaining 7.5 mL for calcium and phosphate ion release measurements. After solution extraction, the samples were replaced in 15 mL fresh deionized water at 37°C until the next sampling time point. Ionic recharge was performed with 5% sodium fluoride varnish (FluoroDose, Centrix) and MI paste plus (GC) following the ion release-testing period. An ion meter with a Fluoride ionic selective electrode were used to determine fluoride concentration. A Microwave-Plasma Atomic Emission Spectrometer (MP-AES) was used to test the concentration of the calcium and phosphate. For the shear bond strength test, rectangular shaped ceramic samples with the dimensions of 2 mm x 12 mm x 14 mm (Vita Mark II, Vita) were fabricated. Standard edgewise-metal brackets (American Orthodontics) were bonded to the center of the ceramic samples using tested material (n=10 for each material). Excess material was removed, and the cementing materials were polymerized from each side for 20 seconds. Specimens were either stored in water for 24 hours at 37o C or went under thermocycling for 5000 cycles. After the storage period, the specimens were subjected to shear bond strength test using an Instron universal machine at a crosshead speed of 0.5mm/min. Loads to failure were recorded to calculate shear bond strength. Comparison of released/recharged ions and shear bond strength were done by ANOVA and Tukey-Kramer HSD (α = 0.05) using JMP Pro 13. RESULTS: RMGIC showed significantly higher fluoride release and recharge than BG composite and the control. BG showed significantly higher Ca and P ion release compared to RMGIC followed by composite. RMGIC and BG showed significant ion recharge capability compared to composite. For the shear bond strength, the control composite showed significantly higher shear bond strength than BG composite followed by RMGIC. Thermocycling significantly increase bond strength for RMGIC and control but not for BG composite. CONCLUSIONS: 1. A fluoride containing bioactive glass composite was fabricated that showed the ability of ion release and recharge. 2. There was a significant difference in the amount of ion release and recharge among tested materials at different time points. 3. Favorable fluoride, calcium and phosphate ion release and recharge of BG composite were maintained over the testing period. 4. BG composite showed favorable bond strength to orthodontic metal brackets. 5. Thermocycling had a significant influence in bond strength for the materials tested except for BG composite. / 2020-07-18T00:00:00Z

Objectives: The aim of this study was to evaluate dental and/or skeletal changes following orthodontic treatment with Damon self-ligating (SL) brackets in non-extraction patients. Methods: Frontal and lateral cephalomteric radiographs of 20 patients before and after non-extraction treatment with Damon SL brackets were analyzed in a three-dimensional analysis computer program (3DCeph, UIC, IL., USA). Changes of intermolar and intercanine distances, incisor positions and maxillary basal bone width of Damon treated subjects were compared to corresponding untreated controls (Bolton templates). Comparisons between the two groups were made with Nonparametric (Mann-Whitney U) test. Results and Conclusions: Transverse changes in distances between crowns of upper and lower first molars and canines in Damon group were similar to untreated individuals (P >0.01). However, in Damon group distances between roots of upper molars and lower canines increased 4.59 and 3.49 mm respectively, compared with 0.8 and -0.01 mm in the Control group (P <0.001, P= 0.001). Lingual root torque of upper incisors and proclination of lower incisors were larger in the Damon group (P<0.05). Damon treatment did not result in buccal tipping of molar crowns or maxillary base width increase (P>0.05). Overall, teeth alignment with Damon system was accomplished with a combination of arch width changes and incisor proclination and/or lingual root torque.

Thesis (M.Sc.)--University of Alberta, 2010. / A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Medical Sciences - Orthodontics. Title from pdf file main screen (viewed on November 29, 2009). Includes bibliographical references.