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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Avaliação mecânica da fixação da osteotomia Le Fort I com placas de avanço pré dobradas e miniplacas convencionais tipo "L" dobradas manualmente = Mechanical evaluation of Le Fort I osteotomy using prebent advancement plates and conventional "L" miniplate fixation hand bent / Mechanical evaluation of Le Fort I osteotomy using prebent advancement plates and conventional "L" miniplate fixation hand bent

Pozzer, Leandro Souza, 1986- 07 August 2015 (has links)
Orientador: José Ricardo de Albergaria Barbosa / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-28T00:10:07Z (GMT). No. of bitstreams: 1 Pozzer_LeandroSouza_D.pdf: 8293531 bytes, checksum: 4e4d7f9683c4cd7bf39fd5b3c7755600 (MD5) Previous issue date: 2015 / Resumo: A cirurgia ortognática é o procedimento cirúrgico mais utilizado para correções das deformidades dentofaciais. Para excessos ou deficiências maxilares o tipo de osteotomia mais utilizado é a osteotomia Le Fort I. Neste trabalho comparamos dois métodos de fixação da maxila após a osteotomia Le Fort I para avaliar a resistência mecânica entre placas de avanço pré-dobradas e miniplacas convencionais tipo "L", ambas do sistema 1,5mm com parafusos de 5mm de comprimento (ENGIMPLAN, Rio Claro/SP/Brasil). Para esse estudo foi desenvolvido um estudo mecânico em réplicas de terço médio da face em resina de poliuretano com a maxila cortada simulando a osteotomia Le Fort I (Nacional Ossos ¿ Jaú/SP/Brasil). Após um avanço de 5mm, dez réplicas de terço médio da face de poliuretano com osteotomia Le Fort I foram separados em 2 grupos (5 modelos em cada grupo), de acordo com a técnica de fixação. Grupo I - 2 placas de avanço pré-dobradas fixas no pilar canino (n=5) e grupo II - 4 miniplacas convencionais tipo "L" dobradas manualmente, sendo 2 placas fixadas no pilar canino e 2 placas fixadas nos pilares zigomáticos, (n=5). As amostras foram acopladas a um suporte metálico especialmente desenvolvido para o teste e foram posicionadas na máquina de ensaio universal Instron (modelo 4411, Norwood/USA) e submetidas a uma carga linear axial na linha média entre os incisivos centrais com velocidade de 1 mm/min, até o deslocamento em 3mm. Os dados obtidos em newtons (N) foram computados pelo software Bluehill 2 (2004) interligado à Instron e então foram submetidos à análise estatística pelo software SPSS/PC 20.0 (Chicago, USA) e foi realizado o teste t para amostra independentes (ANOVA) e o limite de significância estatística foi p<0,05. Dessa forma, o grupo II (placas convencionais tipo L) apresentou maior resistência estatisticamente significativa (p = 0,003), quando comparado ao grupo I (placas de avanço pré-dobradas). Sendo assim, o sistema de fixação com miniplacas convencionais tipo L" promoveu uma melhor estabilidades dos segmentos em comparação com o sistema de placas de avanço pré-dobradas, quando submetido a uma carga axial linear na linha média dos incisivos centrais / Abstract: The orthognathic surgery is the most common procedure realized to treat the dentalfacial deformities. For excess or deficiencies of the maxila the most common is the Le Fort I osteotomy. In this study we compared two fixation methods of the maxila after Le Fort I osteotomy to evaluate the mechanical resistence between advancement pre bent plates and conventional "L" miniplates, both of them of the 1.5mm system and screws with 5mm of length (ENGIMPLAN, Rio Claro/SP/Brasil). For this was developed a mechanical study using midface poliurethane replicas with the maxilla cut simulating Le Fort I osteotomy (Nacional Ossos ¿ Jaú/SP/Brasil). After the maxillary advancement of 5mm, ten midface poliurethane replicas with Le Fort I osteotomy were split into two groups (5 poliurethane midface replicas in each group), according to the fixation technique: Group I ¿ 2 advancement pre bent plates at the canine buttress (n=5) and the group II ¿ 4 conventional "L" miniplates, 2 "L" miniplates at the canine buttress and other 2 "L" miniplates at the zygomatic buttress (n=5). The samples were adapted to a metalic support specially developed for this study and than were positionated at the universal testing machine INSTRON (model 4411, Norwood/USA) and than they were submitted to an axial load in the midline between the upper central incisors with 1mm/min speed, until 3mm of displacement. The data were obtained in newtons (N) and they were processed using the Bluehill 2 (2004) software connected to Instron machine and than the results were submitted do the statistical analysis usign the SPSS/PC 20.0 software (Chicago/USA) and was done the t test for independent sample (ANOVA) and the statistical signifcance limit was p<0,05. Thereby, the group II (conventional "L" miniplates) presented major mechanical resistence statistically significant (p=0,003), when compared to the group I (advancement pre bent plates). Thus, the conventional "L" plates fixation system promoted better stability of the maxila in comparison with advancement pre bent plates when submitted to an axial load in the midline of the central upper incisors / Doutorado / Cirurgia e Traumatologia Buco-Maxilo-Faciais / Doutor em Clínica Odontológica
2

Long-term three dimensional stability of orthognathic surgery

AlMugairin, Sarah Abdullah 30 June 2019 (has links)
PURPOSE: The aim of this study was to evaluate the stability of different orthognathic surgical procedures. METHODS: CBCT scans of 61 patients who had orthognathic surgery were reviewed. These included pre-operative (T0), postoperative (T1), and at least one year postoperative (T2) (12-47 months) scans. All subjects had undergone maxillomandibular advancement surgery, with 23 subjects having clockwise rotation, and 38 having counterclockwise rotation of the mandibular occlusal plane. Mimics Innovation Suite™ Research Edition software (version 21) (Leuven, Belgium) was used for analysis. Thirty-seven parameters were chosen that represented the maxillary and mandibular segments. Measurements between points and/or planes were used to detect the sagittal, vertical, and transverse movements in each time interval. Linear mixed models analysis was used to detect significant differences between time points. Linear regression analysis was used to evaluate the correlations between the amount of surgical movement and the postoperative changes. RESULTS: Overall, 17 measurements showed significant differences between T1 and T2 (postoperative). 11 measurements presented statistically significant time point differences according to either direction of rotation. Only one measurement showed statistically significant difference between T1-T2 (Left ramus plane- Mid sagittal plane) in clockwise group while 8 other measurements were found significantly different between T1-T2 in the counterclockwise group. CONCLUSION: Except for mandibular advancement measured at right and left mental foramen to right and left lingulae, and interlingula distance, bimaxillary advancement surgeries with clockwise or counterclockwise rotation of the mandibular occlusal plane were stable at least for one year. The main difference between clockwise and counter clockwise surgeries was found in the vertical changes of the posterior maxilla and the distance between the right and left mental foramen to the coronal plane.
3

Correction of dentofacial deformities with orthognathic surgery:outcome of treatment with special reference to costs, benefits and risks

Panula, K. (Kari) 09 May 2003 (has links)
Abstract Considerable amounts of research have been done on various aspects of orthognathic surgery during its short history. Nevertheless, there are no comprehensive publications on the cost-risk-benefit analysis of the entire process of orthognathic surgery. The purpose of the present study was to evaluate the psychosocial and biophysiological outcomes of orthognathic surgery with special reference to complications and financial costs. The study series consisted of patients referred for consultations and treatment of dentofacial deformities and involved a total of 953 patients and 20 controls. Both prospective clinical follow-up examinations with measurements of various clinical parameters and retrospective assessments of radiographs and patient records were included. Functional and pain-related reasons were found to motivate patients to seek orthognathic surgery, and this impression was confirmed by the clinical findings. The great majority of the subjects examined had signs and symptoms of temporomandibular disorders (TMD). The significance of facial appearance for the motivation to seek treatments seemed to play a lesser role compared to most earlier studies. Most of the patients felt that their expectations had been fulfilled by the treatment, and despite the potential risks involved, the overall complication rate in orthognathic surgery was very low. The most usual problem was neurosensory deficit of the inferior alveolar nerve. TMD patients with skeletal Class II non-open bite dentofacial deformity seem to have the greatest probability to benefit from orthognathic surgery, especially if their TMD is mostly of muscular origin. Pain in the face and headache improved significantly. The outcomes were more variable when the TMD mainly originated from internal derangements. In these cases, the individual outcome of treatment is more difficult to predict, and conservative treatment methods should probably be tried first. The orthognathic surgery of patients with non-open bite skeletal Class II dentofacial deformity is also cost-effective due to the low complication rate and the low cost, since sagittal ramus osteotomy is often sufficient treatment. However, there must be weighty grounds for orthognathic surgery of skeletal open-bite deformities due to their greater risk for relapse and condylar resorption. The high expenses of their treatment also result in a poor cost-effectiveness ratio.
4

Effects of orthognathic surgery on quality of life compared with non-surgical controls in an American population

Swamy, Charu 24 May 2013 (has links)
No description available.
5

Effects of Orthognathic Surgery on Quality of Life Compared with Non-Surgical Controls in an American Population: A Cross-Sectional Study

Salaita, Rashelle 21 May 2015 (has links)
No description available.
6

Comparison of Two Survey Instruments Measuring Quality of Life in Pediatric Dentofacial Patients

Carlotto, Alan Gabriele 16 June 2017 (has links)
No description available.
7

Avaliação da aplicabilidade de um padrão cefalométrico norte-americano em pacientes brasileiros submetidos à cirurgia ortognática / Evaluation of the applicability of a north american cephalometric norm in brazilian patients submitted to orthognathic surgery

Giglio, Fernando Paganeli Machado 13 September 2006 (has links)
Estudou-se a aplicabilidade de um padrão cefalométrico norte-americano em pacientes brasileiros submetidos à cirurgia ortognática, por meio da comparação dos traçados cefalométricos pós-tratamento ortodôntico-cirúrgico de 29 pacientes (14 homens e 15 mulheres), que passaram por cirurgia de maxila e mandíbula, com ou sem mentoplastia, com o padrão cefalométrico utilizado como orientação para o planejamento dos casos. Os traçados foram gerados pelo programa Dolphin Imaging 9.0 a partir de telerradiografias em norma lateral digitalizadas, nas quais foram marcados 48 pontos de referência dentários, ósseos e de tecidos moles. Dessa forma, obteve-se 26 grandezas cefalométricas lineares e angulares para posterior comparação com os valores normativos norte-americanos, considerando-se o dimorfismo sexual e as eventuais modificações feitas no planejamento em virtude das necessidades individuais de cada caso e das possíveis diferenças étnico-raciais. Os dados da amostra foram confrontados com o padrão individualmente de maneira descritiva e em conjunto, por meio da comparação das médias e desvios-padrão com o teste \"t\" de Student. Os resultados mostraram que para os homens as médias da amostra foram significantemente diferentes do padrão em apenas cinco das grandezas estudadas, enquanto que para as mulheres, nove apresentaram diferença estatisticamente significativa. No entanto, apesar da similaridade das médias na maioria das medidas em ambos os gêneros, os dados mostraram grandes variações individuais. A análise dos resultados obtidos sugere que o padrão cefalométrico norte-americano estudado é aplicável como referência para o planejamento de casos ortodôntico-cirúrgicos de pacientes brasileiros desde que se atente às variações individuais, caracterizando o planejamento de acordo com as necessidades de cada paciente. / It was studied the applicability of a North American cephalometric norm in brazilian patients submitted to orthognathic surgery, through the comparison of the posttreatment cephalometric values of 29 patient (14 men and 15 women), who had bimaxillary surgery, with or without genioplasty, with the cephalometric norm used as orientation for the treatment planning of the cases. The tracings were generated by the program Dolphin Imaging 9.0 from lateral head films that were digitized, in which were marked 48 dental, osseous and soft tissue references points. In that way, it was obtained 26 linear and angular cephalometric measures for subsequent comparison with the normative values, being considered the sexual dimorphism and the eventual modifications done in the planning due to the individual needs of each case and the possible ethnic-racial differences. The data of the sample were confronted individually with the pattern in a descriptive way, and together through the comparison of the averages and standard deviations with the Student \"t\" test. The results showed that for the men the averages of the sample were significantly different from the norm in only five of the studied measures, while for the women, nine cephalometric values presented contrast statistically significant; however, in spite of the similarity of the averages in several measures in both groups, the data demonstrated great individual variations. The analysis of the obtained results suggests that the North American cephalometric norm studied is applicable as reference for the planning of orthognathic surgery in brazilian patients, since it is attempted to the individual variations, characterizing the planning in agreement with the needs of each patient
8

Prevalence and predictors of adverse effects of medical care in patients with cleft lip and palate undergoing facial bone repairs and orthognathic surgical procedures in the United States

Frazier, Kirsten 01 May 2019 (has links)
BACKGROUND AND SIGNIFICANCE: Almost 15% of newborns have congenital anomalies that involve the oral and craniofacial regions, but of these congenital anomalies, cleft lip and palate and craniosynostosis are the most common. It is estimated that the incidence of cleft lip and palate is 0.664 in 1000 live births. These patients commonly have skeletal imbalances of the maxillae and mandible that require surgical and orthodontic correction. Orthodontists and oral surgeons play a critical role in identifying the necessary care and ensuring that the patient receives the best quality of care possible. OBJECTIVES: The objective of the current study is to examine the prevalence of adverse effects of medical care and infectious complications in patients with cleft lip/palate undergoing facial bone repairs/orthognathic surgeries in the United States during the years 2012 to 2014. It will also examine the association between patient/hospital related factors and surgical outcomes (including adverse affects of surgery, incidence of infection, etc.) and how these surgical outcomes impact the hospital costs and length of stay in the hospital. MATERIALS AND METHODS: The Nationwide Inpatient Sample (NIS) is a 20% stratified probability sample of hospitalizations occurring in all acute care hospitals in the United States. It is part of the Healthcare Cost and Utilization Project (HCUP) sponsored by the Agency for Healthcare Research and Quality (AHRQ) [12]. Each hospital in this sample provides information on 20% of hospitalizations occurring during the select years. Hospital stratification is based on multiple hospital-associated variables including: hospital location, geographic region, bed size, teaching status, and ownership/control. Each hospitalization is assigned a sampling weight. Patient-related variables are also provided by the hospitals. In this study, this information is used to provide a nationally representative estimate of all hospitalizations and associated outcomes in the United States from 2012-2014. RESULTS: This study includes all 1,785 patients with cleft lip/palate undergoing facial bone repair/orthognathic surgical procedures in the United States during the study period (2012-2014). These results confirm the hypothesis that there are a combination of patient and hospital related factors that contribute to the occurrence of adverse events and that the occurrence of these events is associated with substantial increases in hospital charges and length of hospital stay. CONCLUSION: These study results are a national representative sample of patients with cleft lip/palate undergoing bony facial repair and orthognathic surgery. They reflect the practice patterns and hospitalization outcomes across the United States. These results can serve as a platform for future prospective controlled studies to examine the risk factors associated with adverse effects of medical care for a wide range of surgical procedures. This information is useful for clinicians, health policy makers, and patients so that they can make informed treatment and policy decisions as well as continue to improve surgical procedures and outcomes.
9

Análise da perda volêmica em pacientes submetidos a expansão rápida de maxila assistida cirurgicamente

Gaetti-Jardim, Ellen Cristina [UNESP] 11 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-11Bitstream added on 2014-06-13T18:17:18Z : No. of bitstreams: 1 jardim_ecg_me_araca.pdf: 229259 bytes, checksum: 15c9095c65db3dcdffe47d437cca73fa (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As cirurgias ortognáticas são procedimentos executados com frequência e complicações como lesões arteriovenosas ou mesmo pelo tempo cirúrgico, podem ocasionar hipovolemia. A necessidade de reposição do volume sanguíneo por meio da infusão de soluções cristalóides, colóides ou até a transfusão de sangue é sempre considerada. Assim, propôs-se neste estudo quantificar a perda sanguínea, bem como avaliar a necessidade da transfusão sanguínea em 19 pacientes submetidos à expansão rápida de maxila assistida cirurgicamente. Foram avaliados os valores de pressão arterial média, tempo de procedimento cirúrgico, gênero, perda volêmica intra-operatória e classificação ASA. Pode-se concluir que a hipovolemia e a requisição de transfusão de sangue nestas cirurgias foram pequenas, entretanto, os profissionais devem sempre estar atentos quanto ao tempo cirúrgico e ao aprimoramento da técnica cirúrgica / Orthognathic surgeries are procedures performed at a frequency quite considerable and now, at the expense of complexity with regard to the complications inherent in the technique, such as arteriovenous injuries or even the time of surgery, can cause a severe hypovolemia. The need for replacement of blood by infusion of crystalloid solutions, colloids or by blood transfusion is always considered. Thus, we proposed this study to quantify the blood loss, and assess the need for blood transfusion in 19 patients undergoing to surgical assisted rapid maxillary expansion. The values of mean arterial pressure, duration of surgery, gender, ASA classification and volume loss. It can be concluded that hypovolemia and the request for blood transfusion in these surgeries were small, however, professionals should always be alert as to the time of surgical procedure and the development of a meticulous surgical technique
10

AvaliaÃÃo da via aÃrea posterior de pacientes submetidos à cirurgia de avanÃo maxilo-mandibular / Airway evaluation of patients undergoing surgery maxillo-mandibular advancement

Phelype Maia AraÃjo 18 October 2012 (has links)
Universidade Federal do Cearà / A cirurgia ortognÃtica (CO) à uma modalidade de tratamento consagrada na resoluÃÃo dos casos de deformidades dento-faciais, porÃm seus movimentos esquelÃticos provocam diversas alteraÃÃes morfolÃgicas e funcionais nos tecidos moles, oclusÃo dentÃria e via aÃrea. Objetivo: Avaliar as alteraÃÃes volumÃtricas e Ãrea de maior constricÃÃo da via aÃrea superior posterior de pacientes submetidos à cirurgia de avanÃo maxilo-mandibular, correlacionando-as entre si e com a estabilidade Ãssea dos resultados obtidos em trÃs momentos T1 - prÃ-operatÃrio; T2 - pÃs-operatÃrio imediato (15 dias) e T3 - pÃs-operatÃrio tardio. Pacientes e MÃtodos: Trata-se de um estudo retrospectivo no qual foram avaliados atravÃs de tomografias computadorizadas de feixe cÃnico em 3 perÃodos distintos, 22 pacientes, 12 homens e 10 mulheres, submetidos a avanÃo cirÃrgico maxilo-mandibular. A quantificaÃÃo, a estabilidade volumÃtrica e à Ãrea de maior constricÃao foi comparada com a estabilidade Ãssea dos movimentos atravÃs de AnÃlise cefalomÃtrica nos pontos ICS para a maxila e Pog para a mandÃbula, nos trÃs tempos do estudo, correlacionados entre si e entre gÃneros, utilizando software especÃfico. Resultados: O movimento de avanÃo maxilo-mandibular proporcionou um ganho volumÃtrico de vias aÃreas entre T1 e T2 de 8,82cm3 (69,0%) (p<0,01) e uma recidiva de 3,7cm3 (42,0%)(p<0,05) entre T3 e T2 e com um ganho real de 40% entre T1 e T3. Na Ãrea de maior constricÃÃo observou-se um aumento de 1,38cm2 (114%)( (p<0,01) entre T1 e T2 e uma perda de 0,25cm2 (18,40%)(p-0,1844) entre T3 e T2. A mÃdia de avanÃo maxilar foi de 5,64mm (p<0,001) e uma recidiva mÃdia de 0,81mm (14,41%) (p-0,3155), a mÃdia de avanÃo mandibular foi de 14,19mm (p<0,001) e uma recidiva mÃdia de 1,17mm (8,23%) (p-0,2960). Encontrou-se uma correlaÃÃo positiva entre aumento da via aÃrea e aumento da Ãrea constricta (r-pearson â 0,7728) e entre o ganho de volume com sua recidiva (r-pearson â 0,5963). NÃo houve diferenÃa estatÃstica entre os genÃros. ConclusÃes: O avanÃo maxilo-mandibular à um movimento esquelÃtico estÃvel a longo prazo. O volume da via aÃrea apresentou um grande aumento no pÃs-operatÃrio imediato, ocorrendo, no entanto, uma recidiva estatisticamente significante em longo prazo, porÃm o aumento da Ãrea de maior constricÃÃo se manteve estavel em longo prazo.

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