Thesis (M.S.)--University of Michigan, 1950.

Resumo: O objetivo dessa tese foi avaliar os efeitos da intrusão ortodôntica no processo de reparação de lesão de furca grau III em cães, e da presença de fator de necrose tumoral alfa (TNFα) e/ou interleucina-1 beta (IL-1ß) na mecanoresposta de células com característica de osteócitos e osteoblastos in vitro. No estudo in vivo, lesões de furca grau III foram criadas em pré-molares inferiores de sete cães. Após 75 dias, as lesões foram aleatoriamente tratadas com cirurgia a retalho (OFD) associada ou não à regeneração tecidual guiada (GTR) e enxerto ósseo autógeno (BA). Após um mês, iniciou-se a intrusão ortodôntica (I) em parte dos dentes tratados pelas duas diferentes abordagens (grupos teste), por meio de ancoragem em miniimplantes. Os cães foram sacrificados após três meses de movimentação e um mês de contenção. Todas as lesões de furca grau III foram reduzidas para grau II ou I nos grupos teste. O mesmo foi observado em 50% das lesões nos grupos controle (sem movimentação). O nível de inserção clínico foi reduzido nos grupos teste, no final da contenção (p<0.01). O grupo OFD+I apresentou maior preenchimento ósseo que os demais grupos (p<0.05), demonstrando superioridade desta associação, no tratamento de lesões de furca grau III, em cães. Esses resultados levantaram a hipótese de que o processo de degradação da membrana e/ou enxerto ósseo interagiria negativamente sobre o processo de reparo quando associado a forças ortodônticas, pois a presença de mediadores inflamatórios estaria intensificada. É conhecido que a alteração tecidual proveniente da movimentação ortodôntica é resultado da ação de mediadores químicos sobre as células dos tecidos periodontais. Portanto, buscamos avaliar in vitro a ação de duas citocinas pró-inflamatórias, TNFα e IL-1ß, sobre células ósseas em presença e ausência de carga mecânica. / Abstract: The aim was to assess the effects of orthodontic intrusion on the healing of class III furcation lesions in dogs, and of the presence of tumor necrosis factor alpha (TNFα) and/or interleukin-1 beta (IL-1ß) on the mechanoresponse of osteocyte and osteoblast-like cells in vitro. In the in vivo study, class III furcation lesions were created in lower pre-molars of seven mongrel dogs. After 75 days, teeth were randomly treated with open flap debridment (OFD) associated or not to guided tissue regeneration (GTR) and bone autograft (BA). After one month, teeth were randomly assigned to orthodontic intrusion using mini-implants anchorage or no movement. Dogs were sacrificed after three months of movement and one month contention. All class III furcations were closed or reduced to class II or I lesions in the intrusion groups while 50% of the class III lesions in non-moved teeth remained unchanged. Clinical attachment level was reduced in the intrusion groups by the end of contention (p<0.01). OFD + I presented smaller soft tissues area and larger bone tissue area than other groups (p<0.05). Orthodontic intrusion with mini-implants anchorage improved healing of class III furcation defects after OFD in dogs. Based on these results we hypothesized that degradation of membrane and/or bone autograft can negatively interfere on repair when associated to orthodontic movement because inflammatory mediators are intensified. It's known that cytokines are present during orthodontic movement which are acting on periodontal cells. Therefore we evaluated in vitro the effects of two pro-inflammatory cytokines, TNFα and IL-1ß, on bone cells in presence or absence of mechanical loading. / Orientador: Joni Augusto Cirelli / Coorientador: Rosemary Adriana Chiérici Marcantonio / Banca: Ana Cláudia Moreira Melo / Banca: Enilson Antonio Sallum / Banca: Ary dos Santos Pinto / Banca: Silvana Regina Perez Orrico / Doutor

Orientador: Rafael Leonardo Xediek Consani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-14T14:57:31Z (GMT). No. of bitstreams: 1 Lopes_MichelleCristina_M.pdf: 433524 bytes, checksum: 7d01d350cce34280c9bae82f9e766739 (MD5) Previous issue date: 2009 / Resumo: O propósito neste estudo foi verificar a movimentação linear de dentes em prótese total superior confeccionada em resina acrílica, com conteúdo de monômero na proporção monômero-polímero indicado pelo fabricante, com 25% de excesso e com 25% a menos, nas técnicas de polimerização convencional e por microondas. Foram confeccionados 30 modelos em gesso pedra tipo III, a partir de um molde de silicone, representando uma arcada maxilar desdentada com rebordo normal. As bases de prova foram confeccionadas com espessura de ±2,5mm e os planos de orientação em cera, com 1cm de altura posterior e 2 cm de altura anterior. O modelo de gesso com o plano de orientação em cera foi fixado no ramo superior do articulador semi-ajustável, com distância intercondilar média, ângulo de Bennet em 15 graus e guia condilar em 30 graus. Em seguida, um modelo de arcada mandibular dentada foi posicionado sobre o plano de cera do modelo superior e fixado na haste inferior do articulador, posicionando o pino incisal em zero. Depois da montagem dos dentes artificiais, o modelo da prótese foi removido do articulador e moldado com silicone. Os dentes foram colocados no molde e sobre eles foi vertida cera rosa liquefeita, até o completo preenchimento do molde. Antes da solidificação da cera, o modelo de gesso foi adaptado no molde e mantido em posição até o completo esfriamento da cera, quando o conjunto modelo de gesso-base de prova com dentes artificiais foi removido do molde. Foram confeccionados pontos referenciais sobre a região mediana da borda incisal dos incisivos centrais, cúspide vestibular dos primeiros pré-molares e cúspide disto-vestibular dos segundos molares, por meio de perfurações para fixação de segmentos de alfinetes metálicos com adesivo instantâneo à base de cianoacrilato. As mensurações foram realizadas nas distâncias transversais entre: incisivos centrais; primeiros pré-molares; e segundos molares, e ântero-posteriores entre: incisivo central direito e molar direito; incisivo central esquerdo e molar esquerdo, com microscópio comparador linear antes da inclusão e depois do acabamento das próteses. Nos grupos com proporção recomendada pelos fabricantes, as próteses foram prensadas convencionalmente. Nos demais grupos, os mesmos procedimentos foram adotados, com exceção da proporção de monômero que foi de 25% a mais ou 25% a menos. Os dados de deslocamento dental foram submetidos à análise de variância e ao teste de Tukey (5%). Não houve diferença estatística entre os grupos com quantidade de monômero recomendada pelo fabricante (grupo controle) e os demais grupos tanto na polimerização convencional como por microondas. A alteração na quantidade de monômero para mais ou para menos em relação à proporção monômero-polímero não influenciou a movimentação dental linear nos sentidos transversal e ântero-posterior. / Abstract: The purpose of the study was to verify the linear displacement of the teeth in complete upper denture made with acrylic resin, with monomer content indicated by the manufacturer, with 25% in excess and 25% less, in the conventional and microwaves polymerization techniques. Thirty casts were made with type III stone plaster, based on silicone mould, representing an edentulous maxillary arch with normal edge. The wax baseplates were manufactured in a ±2.5mm thickness and the wax rims with 10 mm of posterior height and 20 mm of anterior height. The stone cast related with the wax rim was fixed at the top stem of semi-adjustable articulator, adjusting the intercondylar distance in Medium, the angle of Bennet in 15 degrees and the condylar guidance in 30 degrees. A mandibular arch with teeth was placed on the wax rim and fixed on the bottom shaft of the articulator, positioning the incisal pin to zero. After mounting the artificial teeth, the denture was removed from the articulator and impressed with silicone. The teeth were placed in the impression mold and over them it was poured a liquid wax, until the mold filling was completed. Before solidification of the wax, the stone cast mold was adapted in the impression and kept in position until the wax setting. After wax setting, the stone cast- denture with artificial teeth set was removed from the silicone impression. Reference points were fixed over the median region of the incisal edge of central incisors, buccal cusp of the first premolar and distal-buccal cusp of the second molars in drill holes performed for fixation of the metal pin segments with instantaneous adhesive based on cyanoacrylate. The measurements were made in the transverse distances among: central incisors; first premolar; second molar, and anteroposterior among: central right incisor and right molar; central left incisor and left molar, with a linear comparator microscope before and after denture procedure. In the groups with monomer content recommended by the manufacturer, the dentures were conventionally pressed. In the other groups, the same procedures were adopted, with exception of the monomer content that was 25% in excess or 25% less. The dental displacement data were submitted to ANOVA and Tukey's test (5%). There was no statistically significant difference among the groups with the monomer content recommended by the manufacturer and other groups, in both conventional and microwaved activations. To change the content of monomer to more or less in relation to monomer-polymer proportion did not influence the linear displacement of the teeth in transverse or anteroposterior directions. / Mestrado / Protese Dental / Mestre em Clínica Odontológica

During orthodontic tooth movement, stress is applied on the dento-alveolar complex, initiating a biological response. This response results in the remodelling of the periodontal ligament and the alveolar bone. When a force is placed on a tooth, the periodontal ligament is stretched and compressed depending on the direction of force. On the side where the ligament is stretched, a response resulting in bone deposition is initiated. On the opposite side, where the periodontal ligament is compressed, a response resulting in the resorption of bone begins. These responses are believed to be modulated by factors that are derived from the immune or nervous systems. When stress is placed on the periodontal ligament, it is believed that nerve fibres and neuroreceptors within the tissue are distorted, leading to the release of neurotrophins and a common concomitant clinical response of pain and pressure. These neurotrophins may interact with cells within the dentoalveolar complex, including fibroblasts, endothelial and alveolar bone cells, resulting in the initiation of bone resorption via the activation of intracellular secondary messengers, which leads to cellular proliferation and differentiation. Neurotrophin levels may play a role in the modulation of cellular activity in the periodontal ligament during orthodontic movement. They are a family of protein polypeptides which are important in neural cell differentiation and survival. One relatively well studied member of the family, Nerve Growth Factor (NGF), is a polypeptide essential for supporting cholinergic innervation in the brain and sympathetic and sensory innervation in the peripheral tissues. Within the dento-alveolar complex, the function and localization of neurotrophins and their receptors are yet to be determined. Previous studies have shown that there is an increase in NGF expression in tissues in response to injury, suggesting that NGF expression may increase in regions within the dento-alveolar complex where inflammation and bone remodelling are occurring. A study showed elevated levels of NGF mRNA in human periodontal ligament cells in vitro during increased transcription and translation of the bone-related proteins alkaline phosphatase and osteopontin, suggesting NGF facilitates bone formation. The NGF may be modulating cellular activity within the periodontal ligament. O’Hara et al. used immunohistochemical staining in the rat dento-alveolar complex to show that there was evidence of an increase in NGF synthesis and release by certain cells or tissues within the region of alveolar bone remodelling during the initial injury response period to orthodontic tooth movement. Ho used a similar model to test the hypothesis that there may be a positive relationship between the presence of osteoclasts and pre-osteoclasts with areas of NGF localisation. He found no relationship between osteoclasts and areas of NGF; however, his findings showed areas of unknown tissue within the periodontal ligament that were associated with NGF. To date, the relationship between NGF and the cellular process of orthodontic tooth movement remains unknown. Further studies are required to describe the distribution of neurotrophins and neurotrophic receptors and cellular interactions within the rat dento-alveolar complex. / Thesis (D.Clin.Dent.) -- University of Adelaide, School of Dentistry, 2010

Thesis (M. Sc.)--University of Manitoba, 1994. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (doctoral)--Karolinska Institutet, Stockholm, 1983. / Extra t.p. with thesis statement inserted. Includes the author's six articles published in various journals. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (doctoral)--Karolinska Institutet, Stockholm, 1983. / Extra t.p. with thesis statement inserted. Includes the author's six articles published in various journals. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M. Sc.)--University of Manitoba, 1994. / Includes bibliographical references.

Orientador: Osmar Aparecido Cuoghi / Coorientadora: Roberta Okamoto / Banca: Maria Gisette Arias Provenzano / Banca: Adilson Luiz Ramos / Banca: Edilson Ervolino / Banca: Marcos Rogério de Mendonça / Resumo: Introdução: A aplicação de diferentes tipos de força pode provocar comportamentos distintos no osso alveolar. Proposição: avaliar se o lado contra-lateral (CL) a movimentação dentária induzida pode ser usado como grupo controle e a variação da quantidade de tecido ósseo frente a aplicação dos diferentes tipos de força em molares murinos. Métodos: Utilizou-se 60 ratos machos (Wistar-Rattus norvergicus), com aproximadamente 90 dias de idade e peso de 300g, divididos em 4 grupos de acordo com o tipo de força; Grupos controle (C), força contínua (FC), força contínua interrompida (FCI) e força intermitente (FI). As forças foram aplicadas nos períodos de 5, 7 e 9 dias (n=6) e analisou-se a quantidade de tecido ósseo alveolar. Os dados foram tabulados e realizou-se o teste estatístico com nível de significância de 5% (p<0,05). Resultados: houve diferença estatisticamente significante nos percentuais de colágeno entre os grupos C (80% ±0,01) e FC (62,2% ±0,15) e que o grupo CL foi estatisticamente igual aos demais grupos. A imunomarcação de OPG, o grupo C e o CL se comportaram de forma semelhante. A RANKL, na face mesial do grupo CL se comportou de forma semelhante ao FC e sua face distal diferiu dos demais grupos. A face distal do grupo C obteve score semelhante a face distal do grupo FC. A análise do tecido ósseo inter-grupos mostrou que aos 5 dias de MDI houve diminuição significante dos percentuais de osso dos grupos FC (62% ±0,14), FCI (55% ±0,07) e FI (54% ±0,05) em relação ao grupo C (80% ± 0,01) (p<0,05). Aos 7 dias de movimentação, essa diminuição ainda era significante nos grupos FC (64% ± 0,1) e o FI (38% ± 0,1) quando comparados ao grupo C (80% ± 0,01) e também houve diferença estatisticamente significante entre o FC (64% ± 0,1) e FI (38% ± 0,1) (p<0,05). Aos 9 dias de movimentação, essa diminuição foi significante... / Abstract: Introduction: There are few researches about the behavior of the alveolar bone in relationship of three different types of forces. Objective: To evaluate if the bone on the contralateral side to orthodontic tooth movement can be used as the control group (CL) and the amount of bone tissue during the application of different types of force in rats molars. Methods: 60 male rats (Rattus norvegicus Wistar), with approximately 90 days of age and weight of 300g, divided into 4 groups according to the type of force: control group (C), continuous force (CF), intermittent continuous force (ICF) and interrupted force (IF); The groups were distributed in periods of 5, 7 and 9 days (n = 6). Were analyzed the amount of bone tissue of right upper first molar. The evaluation were conducted with Anova and Tukey's tests a significance level of 5% (p <0.05). Results: The collagen analysis demonstrated a statistically significant difference between the C group (80 ± 0.01%) and CF (62.2 ± 0.15%), whereas no significant differences were found between the CL group and the other groups. Immunolabeling for OPG was similar in the C and CL groups. RANKL on the mesial face was similar in the CL and CF group. However, significant differences were found between the CL group and the other groups on the distal face, whereas no significant difference on the distal face was found between the C and CF group. The intergroup bone tissue analysis showed that the five days of induced tooth movement (ITM) was no significant decrease in bone percentage of CF groups (62% ± 0.14), ICF (55% ± 0.07) and IF (54% ± 0, 05) in the C group (0.01 ± 80%) (p <0.05). At 7 days of ITM, this reduction was still significant in the CF group (64% ± 0.1) and IF (38% ± 0.1) compared to C group (80% ± 0.01) and there was also difference statistically significant between CF (64 ± 0.1%) and IF (38% ± 0.1)... / Doutor

Resumo: O objetivo deste estudo foi analisar o aspecto qualitativo e quantitativo da distribuição das tensões provenientes de molas helicoidais utilizadas na verticalização de molares pelo método da fotoelasticidade de transmissão plana. Foram confeccionados seis modelos fotoelásticos simulando um quadrante inferior direito com canino, primeiro e segundo pré-molares, bem como com o segundo molar inclinado para mesial. As molas foram confeccionadas em fios retangulares .019 x .025" em aço inoxidável com comprimentos de 20mm (AI 20), 25mm (AI 25) e em TMA com 20mm (TMA 20) e 25mm (TMA 25), ativadas com força de 100cN. A análise fotoelástica demonstrou maior concentração de franjas de tensões adjacentes ao molar do que na unidade de ancoragem. A região cervical mesial do molar apresentou os maiores níveis de tensões. A região da bifurcação radicular apresentou os menores níveis de tensões. A mola AI 25 apresentou os maiores índices de tensões nas regiões cervicais mesial e distal bem como nas apicais mesial distal da raiz. A mola TMA 20 apresentou os menores índices de tensões, exceto na região intermediária da raiz. / Abstract: This paper is gived purpose to analyze the quantitative and qualitative aspect of the stress distribution resulting for the helicoidal springs used in the uprighting of the molars through the photoelasticity method of transmission. Six models of photoelastic resin was made simulating a right lower hemiarc with canine, first and second premolar and second molar for mesial inclined. The springs was made with rectangular wire .019 x .025" in stainless steel with length of 20mm (AI 20), 25mm (AI 25) and in TMA with 20mm (TMA 20) and 25mm (TMA 25), active with 100cN of force. The photoelastic analyses showed highest concentration of stress fringes adjacent in the molar as compared with the anchorage unity. In the cervical mesial region occurred of higher levels of the tensions. In the radicular bifurcation regions showed the lowest levels of the tensions. Spring AI 25 showed the highest rates of tensions in the regions cervical mesial and distal as well as in the apical mesial and distal of the root. Springs TMA 20 showed the lowest rates of tension, except in the intermediate region of the root. / Orientador: Osmar Aparecido Cuoghi / Coorientador: Cleudmar Amaral Araújo / Banca: Marcos Rogério de Mendonça / Banca: Guilherme de Araújo Almeida / Mestre