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Avaliação das alterações volumétricas da cavidade nasal decorrentes da expansão rápida de maxila assistida cirurgicamente /Oliveira, Ariane de Souza. January 2016 (has links)
Orientador: Valfrido Antonio Pereira Filho / Banca: Marisa Aparecida Cabrini gabrielli / Banca: Eduardo Sanches Gonçales / Resumo: O objetivo desta pesquisa foi avaliar as alterações volumétricas da cavidade nasal de pacientes diagnosticados com deficiência transversa de maxila submetidos à expansão rápida de maxila assistida cirurgicamente. Foram avaliadas tomografias computadorizadas de feixe cônico de 28 pacientes adultos (17 mulheres e 11 homens), em três períodos distintos, a saber: período pré-operatório imediato (T1), pós-operatório ao final da expansão (T2) e 6 meses após do término da expansão (T3), no qual as imagens, em formato DICOM, foram importadas e reconstruídas por meio do software On Demand 3D, que permitiu a reconstrução multiplanar da região de interesse de maneira padronizada. Para cada imagem do corte gerado, dois examinadores treinados delimitaram manualmente o espaço aéreo nasal, utilizando o software ImageJ. Com base no principio de Cavalieri, a soma de todas as áreas medidas em cada paciente/período foi utilizada para gerar o volume da estrutura avaliada, em milímetros cúbicos. Os dados obtidos foram verificados pelo teste ANOVA e teste de Tukey, com nível de significância de 5%. Concluiu-se que as expansões maxilares cirurgicamente assistida em adultos não promoveram alterações de volume da cavidade nasal. / Abstract: The objective of this study was to evaluate the volumetric changes of the nasal cavity in patients with transverse maxillary deficiency after surgically assisted rapid maxillary expansion. Cone beam tomographic images of 28 adult patients (17 women and 11 men) were evaluated. They were obtained after three different time periods: immediate preoperative period (T1), postoperative after completion of expansion (T2) and 6 months after expansion (T3). The DICOM images were imported and reconstructed through the On Demand 3D software, which allowed standardized multiplanar reconstruction of the interest region. For each image two examiners manually delimited the nasal air space, using the Image J software. Based on the Cavalieri principle, the summation of all measured areas in each patient/period was used to calculate of the volume in cubic millimeters. The data were analysed by the ANOVA and Tukey tests at 5% significance level. It was concluded that surgically assisted maxillary expansion in adults did not promote volume changes of the nasal cavity. / Mestre
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Effects of dental loss and senescence on aspects of adult mandibular morphology in South AfricansOettle, Anna Catherina January 2015 (has links)
Changes occur to the mandible with dental loss and senescence. However, the influence that these changes have on sex and ancestry estimations remains unclear. The purpose of this study was to investigate the influence of dental loss and senescence on changes in mandibular morphology. The outcome has implications for both forensic anthropology and restorative dentistry. The study sample consisted of 717 mandibles consisting of both male and female South Africans of African (SAA) and European ancestry (SAE). To minimise the effects of variation in dentition amongst sex-ancestry groups, the sample included individuals with a spectrum of tooth loss patterns, namely efficient and inefficient occlusions as well as no occlusions. Dentition was considered efficient when the remaining teeth in occlusion were evenly distributed between the sides. Linear measurements as well as geometric morphometric shape analyses were performed. Shape analyses of the complete mandible were performed on models from digitised landmarks by using a MicroScribe G2. Detailed shape analyses of the ramus and chin area as well as measurements of the cortical thickness at specific sites were executed on images generated by cone beam computed tomography (CBCT). A comprehensive assessment of changes in shape, size and cortical thickness of the mandible with age and dental loss were made. Shape and size differences of the mandible were evaluated for discriminant abilities between sex and ancestry groups. Although most dimensions decreased with tooth loss, the greatest impact was noted in the loss of alveolar bone. The mandibular angle increased minimally in size when a few teeth were lost, but recovered to some extent with further tooth loss. The cortical thicknesses at the mental foramen lingually as well as in the midline in females, were relatively spared with tooth loss. Male individuals of SAA were often the most resilient to tooth loss. In general external linear dimensions were maintained with age despite tooth loss. Conversely, measurements of cortical bone thickness decreased slightly, but could have been influenced by dental loss. The shape of the chin and gonial area was more affected by aging in SAE. The sex and ancestry discriminant ability of the linear dimensions when considered collectively approximated 90%, in general improving further when tooth loss was taken into account. All linear measurements were smaller in females and in general tooth loss accentuated sex differences. SAA exhibited greater dimensions, apart from maximum ramus height, bigonial breadth and cortical thickness at the gonion. The mental tubercles were more prominent than the pogonion in SAE (square chin) and vice versa in individuals of SAA (pointed chin). The gonial area in individuals of African ancestry was broad and more convex and the gonial eversion more prominent with a more upright ramus. Discriminant qualities of the gonial shape for sex in individuals of African ancestry reached 90% within dentition groups. Ramus flexure and chin shape were not found to be useful in sex estimation. In conclusion, this research elucidated the effects of tooth loss and senescence on the morphology of the mandible for the forensic anthropological setting. / Thesis (PhD)--University of Pretoria, 2015. / tm2015 / Anatomy / PhD / Unrestricted
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Avaliação das alterações volumétricas da cavidade nasal decorrentes da expansão rápida de maxila assistida cirurgicamente / Evaluation of volumetric changes of the nasal cavity after surgically assisted rapid maxillary expansionOliveira, Ariane de Souza [UNESP] 24 March 2016 (has links)
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Previous issue date: 2016-03-24 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O objetivo desta pesquisa foi avaliar as alterações volumétricas da cavidade nasal de pacientes diagnosticados com deficiência transversa de maxila submetidos à expansão rápida de maxila assistida cirurgicamente. Foram avaliadas tomografias computadorizadas de feixe cônico de 28 pacientes adultos (17 mulheres e 11 homens), em três períodos distintos, a saber: período pré-operatório imediato (T1), pós-operatório ao final da expansão (T2) e 6 meses após do término da expansão (T3), no qual as imagens, em formato DICOM, foram importadas e reconstruídas por meio do software On Demand 3D, que permitiu a reconstrução multiplanar da região de interesse de maneira padronizada. Para cada imagem do corte gerado, dois examinadores treinados delimitaram manualmente o espaço aéreo nasal, utilizando o software ImageJ. Com base no principio de Cavalieri, a soma de todas as áreas medidas em cada paciente/período foi utilizada para gerar o volume da estrutura avaliada, em milímetros cúbicos. Os dados obtidos foram verificados pelo teste ANOVA e teste de Tukey, com nível de significância de 5%. Concluiu-se que as expansões maxilares cirurgicamente assistida em adultos não promoveram alterações de volume da cavidade nasal. / The objective of this study was to evaluate the volumetric changes of the nasal cavity in patients with transverse maxillary deficiency after surgically assisted rapid maxillary expansion. Cone beam tomographic images of 28 adult patients (17 women and 11 men) were evaluated. They were obtained after three different time periods: immediate preoperative period (T1), postoperative after completion of expansion (T2) and 6 months after expansion (T3). The DICOM images were imported and reconstructed through the On Demand 3D software, which allowed standardized multiplanar reconstruction of the interest region. For each image two examiners manually delimited the nasal air space, using the Image J software. Based on the Cavalieri principle, the summation of all measured areas in each patient/period was used to calculate of the volume in cubic millimeters. The data were analysed by the ANOVA and Tukey tests at 5% significance level. It was concluded that surgically assisted maxillary expansion in adults did not promote volume changes of the nasal cavity. / FAPESP: 2014/10239-3
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Biomechanical investigation of the mandible, a related donor site and reconstructions for optimal load-bearingBujtár, P. (Péter) 10 March 2015 (has links)
Abstract
Biomechanics are especially important when it comes to the lower third of the face which is composed of a single load-bearing structure, the mandible. Implementation of recent developments in image processing, material sciences and computational technology allows the verification of these principles defining the appropriate practice. The studies listed in the thesis, benchmark from the simple to the more complicated mandibular surgical procedures. The aims were to build patient specific, custom made, composite reconstructions using newly learned techniques.
Cross-sectional imaging with Cone Beam Computer Tomography was used to build bone models. The mandible at various ages, undergoing minor oral surgery, partial cross-section reduction with or without reinforcements and complete transection were simulated under biting conditions. Industry standard free form modelling, reverse engineering techniques and Finite Element Analysis were used. Internal and external validations of certain modelling elements were introduced.
The mandible became stiffer with increasing age. Minimization of the reduction of the main load-bearing structures was noted to be crucial. The External Oblique Ridge was one such a structure. Partial thickness defects were best spanned by Dynamic Compression Plates. If the remaining amount of bone was insufficient or the bone quality was poor then Locking Compression Plates were preferred. Rounding or the use of a stop-hole was recommended to reduce the risk of fracture development especially without additional Prophylactic Internal Fixation. Fixation using a single reconstruction plate with three screws on either side in the four most common segmental defects was sufficient. Locking monocortical screw fixation was superior over non-locking systems. The suitability of CBCT in bone scanning was demonstrated, highlighting the positional dependent differences within the scanned volume.
It should be noted that the relevance and validity of such simulations depends on the quality and the setup. In the future, biomechanically customized fixation can complement tissue engineering procedures and regenerative techniques by providing the precise physical dimensions and biomechanical requirements of the planned reconstructions. / Abstrakti
Biomekaniikan ymmärtäminen on tärkeää kovakudoskirurgiassa. Periaatteet ovat erityisen tärkeitä, kun kyseessä on kasvojen alin kolmannes, joka muodostuu yhdestä kantavasta rakenteesta eli alaleuasta. Viime aikojen kehitys kuvankäsittelyssä, materiaalitieteessä ja tietokoneteknologiassa ovat mahdollistaneet näiden periaatteiden tarkistamisen käytännössä. Tämän opinnäytetyön osatöissä tutkittiin biomekaniikkaa erityyppisissä leikkauksissa. Tavoitteena on rakentaa tulevaisuudessa potilaille mittatilaustyönä erilaisista materiaaleista korjausosia käyttäen hyväksi uusinta tietoa ja tekniikkaa.
Leikekuvantamista kuten Multi Detectoria ja viime aikoina kartiokeilatietokonetomografiaa (KKTT) käytettiin luumallien valmistamisessa. Eri-ikäisten alaleukoja, joihin tehtiin pieniä suukirurgisia toimenpiteitä, osaosteomioita vahvistuksen kanssa tai ilman vahvistusta ja täydellisiä alaleuan katkaisuja, simuloitiin kuormitusolosuhteissa. Teollisuudessa standardoitua vapaamuotoista mallinnusta ja käänteistä tekniikkaa sekä Finite Element Analysis-menetemää käytettiin. Mallinnuksessa käytettiin lisäksi sisäistä ja ulkoista validointia.
Alaleuka koveni iän myötä. Leuan kestävyyden kannalta oli ratkaisevaa että tärkeisiin kantaviin rakenteisiin puututtiin mahdollisimman vähän. Oblique Ridge oli yksi tällainen rakenne. Osaosteotomioissa paras ratkaisu oli dynaaminen kompressiolevy. Jos jäljelle jäävän luun määrä tai laatu oli heikko niin sitten lukittuvat puristuskompressiolevyt toimivat parhaiten. Luun pyöristäminen tai pysäytysreiän käyttö oli suositeltavaa vähentämään murtumariskiä varsinkin ilman profylaktista kiskotusta. Neljän yleisimmän segmentaalisen defektin kiinnitys yhdellä levyllä ja kolmella ruuvilla levyn molemmin puolin oli riittävä. Lukittuva monokortikaalinen ruuvikiinnitys oli ylivoimainen verrattuna ei-lukittuvaan systeemiin. KKTT osoittautui parhaaksi menetelmäksi alaleuan kuvantamisessa.
Kaikki havainnot voivat toimia yleisohjeena kun harjoitellaan edellä mainittuja toimenpiteitä. On huomattava, että tällaisen simulaation merkitys ja todenmukaisuus riippuu sen laadusta ja asennuksesta. Tulevaisuudessa biomekaanisesti tarkkojen mittausten perusteella suunniteltu luun kiinnitys voi palvella kudosteknologian avulla tehtäviä rekonstruktioita antamalla toimenpiteessä tarvittavat tarkat fysikaaliset mitat ja kuormitusarvot.
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Avaliação das dimensões transversal, vertical e anteroposterior em tomografias computadorizadas do feixe cônico de pacientes com deficiência maxilar transversal submetidos à expansão rápida de maxila assistida cirurgicamente / Transversal, vertical and anteroposterior three-dimensional changes in SARME treatments using Cone-Beam Computer TomographyYamaji, Marco Aurélio Kenichi 28 August 2014 (has links)
O objetivo deste estudo foi uma avaliação tridimensional as mudanças nas dimensões transversais, verticais e anteroposterior das estruturas dentais e dentoalveolares em pacientes com deficiência maxilar transversal (DMT) submetidas à expansão rápida de maxila assistida cirurgicamente (ERMAC) através do uso de tomografias computadorizadas do feixe cônico (TCFC). Trinta e oito pacientes com DMT foram submetidos à ERMAC sob anestesia geral, as TCFC foram realizadas no pré-operatório (T1), após a expansão desejada (T2) e seis meses após a expansão (T3). Quarenta e sete marcações tridimensionais foram realizadas como pontos de referência e marcadas em cada tempo. As distâncias e ângulos foram medidas a fim de se avaliar as alterações ocorridas após a expansão. Os resultados demonstraram diferenças estatísticas significantes na dimensão transversal através do teste ANOVA ao nível da câmara pulpar (P≤0.001) em T2-T1 e T3-T1; e ao nível do ápice dental com diferença estatisticamente significante (P<0.005) em T2-T1 e T3-T1 e ao nível do processo dentoalveolar com diferença estatísticamente significante de (P<0.05) em T2-T1e T3-T1. A inclinação dentária apresentou diferença estatísticamente significante somente no incisivo central esquerdo (P< 0.05) em T3-T1. As dimensões vertical e anteroposterior não apresentaram diferenças estatísticamente significante. As maiores mudanças ocorreram na dimensão transversal na maioria das estruturas avaliadas, alterações verticais e anteroposteriores não foram encontradas. O índice de recidiva após seis meses da realização da ERMAC é baixa e podemos considerar como um tratamento estável para pacientes com DMT. / The objective of this study was evaluate three-dimensional changes on transversal, vertical and anteroposterior dimensions of dental and dentoalveolar structures in patients with maxillary transverse deficiency (MTD) submitted to surgically assisted rapid maxillary expansion (SARME) using by CBCT. Thirty eight subjects with MTD was submitted to SARME under general anesthesia, CBCTs was taken preoperative (T1), after desired expansion (T2) and six months after expansion (T3). Fourth seven three-dimensional landmarks were determinate as reference points and marked at each time. The distances and angles were measured regarding the changes occurred after expansion.The results showed statistical significance difference in transverse dimension by ANOVA test at level of pulp chamber (P≤0.001) at T2-T1 and T3-T1; at level of dental apex had statistical difference (P<0.005) at T2-T1 and T3-T1, at level of dentoalveolar processes had statistical difference (P<0.05) at T2-T1 and T3-T1. Dental tipping showed statistical difference only left central incisors (P< 0.05) at T3-T1 Vertical and anteroposterior dimensions do not have statistical difference. The greater changes occurred in transversal dimensions and most of structures evaluated, no vertical and anteroposterior changes were found. The index relapse after six months is low and SARME can be consider stable to treatment of MTD.
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AVALIAÇÃO TOMOGRÁFICA DA ANGULAÇÃO DOS PRIMEIROS E SEGUNDOS MOLARES E DO ESPAÇO PARA O TERCEIRO MOLAR SUPERIOR APÓS O USO DO APARELHO FORSUS®. / EVALUATION OF UPPER FIRST AND SECOND MOLARS ANGULATION AND THE SPACE FOR THIRD MOLAR AFTER USING THE FORSUS® APPLIANCE.Lima, Carolina Souto 29 March 2011 (has links)
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Previous issue date: 2011-03-29 / The present study aimed to assess the mesiodistal angle, upper first and second molars distalization and the space for upper third molars in patients treated with Forsus® associated to fixed appliance. Sample consisted of 44 lateral
cephalograms (22 right side, and 22 left side) obtained from 11 Cone-Bean Computed Tomography (CBCT) of 11 patients, in two phases: before (T1) and after (T2) the Forsus®. appliance. After obtaining the lateral cephalograms, points, lines and planes were marked, to measure the variables of interest. For evaluation of the space for upper third molars, it was used a reference line (PTVR), from point PTV, perpendicular to Frankfurt plane, measuring the distance until the distal face of first and second upper molars. To evaluate the long axis of upper first and second molars, it was measured the angle formed between such teeth and the palatal plane. The software used was Radiocef Studio 2 and for statistical analysis it was used paired "t" test. Results showed there was distalization and distal tipping of upper first
and second molars, with a greater magnitude in first molars. Alterations in right and left sides were similar. It was also noticed that there was a reduction in the probability of eruption of third molars. / A presente pesquisa avaliou a angulação mésio-distal e a distalização dos primeiros e dos segundos molares superiores permanentes em pacientes tratados com o aparelho Forsus® em conjunto com o aparelho ortodôntico fixo. A amostra foi composta por 44 teleradiografias, (22 do lado direito e 22 do lado esquerdo), obtidas por meio de 11 tomografias computadorizadas, de 11 pacientes, realizadas em dois tempos: antes (T1) e após (T2) a instalação do aparelho Forsus®, tratados na clínica de Pós-Graduação em Odontologia, área de Ortodontia, da Universidade Metodista de São Paulo. Após a obtenção dos cortes tipo telerradiografia, foi realizada a marcação dos pontos, linhas e planos, e realizada a mensuração das variáveis de interesse. Para avaliação do espaço para os terceiros molares superiores, utilizou-se uma linha referencial (linha PTVR), demarcada a partir do ponto PTV, perpendicular ao plano de Frankfurt. O espaço avaliado compreendeu entre a Linha PTVR, até a face distal do primeiro molar e do segundo superior permanente. Para avaliar o longo eixo dos primeiros e segundos molares superiores, mensurou-se o ângulo
formado entre esses dentes e o plano palatino. Para auxílio das mensurações, foi utilizado o software Radiocef Studio 2. Na análise estatística usou-se o teste t pareado. Concluiu-se que houve distalização e aumento da angulação distal dos
primeiros e segundos molares superiores, sendo que nos segundos molares a distalização e angulação distal da coroa ocorreram em menor quantidade; os efeitos do lado direito e esquerdo foram semelhantes; pode-se também constatar que
ocorreu uma redução na probabilidade de erupção dos terceiros molares superiores.
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Avaliação das dimensões transversal, vertical e anteroposterior em tomografias computadorizadas do feixe cônico de pacientes com deficiência maxilar transversal submetidos à expansão rápida de maxila assistida cirurgicamente / Transversal, vertical and anteroposterior three-dimensional changes in SARME treatments using Cone-Beam Computer TomographyMarco Aurélio Kenichi Yamaji 28 August 2014 (has links)
O objetivo deste estudo foi uma avaliação tridimensional as mudanças nas dimensões transversais, verticais e anteroposterior das estruturas dentais e dentoalveolares em pacientes com deficiência maxilar transversal (DMT) submetidas à expansão rápida de maxila assistida cirurgicamente (ERMAC) através do uso de tomografias computadorizadas do feixe cônico (TCFC). Trinta e oito pacientes com DMT foram submetidos à ERMAC sob anestesia geral, as TCFC foram realizadas no pré-operatório (T1), após a expansão desejada (T2) e seis meses após a expansão (T3). Quarenta e sete marcações tridimensionais foram realizadas como pontos de referência e marcadas em cada tempo. As distâncias e ângulos foram medidas a fim de se avaliar as alterações ocorridas após a expansão. Os resultados demonstraram diferenças estatísticas significantes na dimensão transversal através do teste ANOVA ao nível da câmara pulpar (P≤0.001) em T2-T1 e T3-T1; e ao nível do ápice dental com diferença estatisticamente significante (P<0.005) em T2-T1 e T3-T1 e ao nível do processo dentoalveolar com diferença estatísticamente significante de (P<0.05) em T2-T1e T3-T1. A inclinação dentária apresentou diferença estatísticamente significante somente no incisivo central esquerdo (P< 0.05) em T3-T1. As dimensões vertical e anteroposterior não apresentaram diferenças estatísticamente significante. As maiores mudanças ocorreram na dimensão transversal na maioria das estruturas avaliadas, alterações verticais e anteroposteriores não foram encontradas. O índice de recidiva após seis meses da realização da ERMAC é baixa e podemos considerar como um tratamento estável para pacientes com DMT. / The objective of this study was evaluate three-dimensional changes on transversal, vertical and anteroposterior dimensions of dental and dentoalveolar structures in patients with maxillary transverse deficiency (MTD) submitted to surgically assisted rapid maxillary expansion (SARME) using by CBCT. Thirty eight subjects with MTD was submitted to SARME under general anesthesia, CBCTs was taken preoperative (T1), after desired expansion (T2) and six months after expansion (T3). Fourth seven three-dimensional landmarks were determinate as reference points and marked at each time. The distances and angles were measured regarding the changes occurred after expansion.The results showed statistical significance difference in transverse dimension by ANOVA test at level of pulp chamber (P≤0.001) at T2-T1 and T3-T1; at level of dental apex had statistical difference (P<0.005) at T2-T1 and T3-T1, at level of dentoalveolar processes had statistical difference (P<0.05) at T2-T1 and T3-T1. Dental tipping showed statistical difference only left central incisors (P< 0.05) at T3-T1 Vertical and anteroposterior dimensions do not have statistical difference. The greater changes occurred in transversal dimensions and most of structures evaluated, no vertical and anteroposterior changes were found. The index relapse after six months is low and SARME can be consider stable to treatment of MTD.
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