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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.
341

Comparação da anatomia transversal de mandíbula de indivíduos classe III com e sem fissura labiopalatina por meio de tomografia de feixe cônico / Comparison of transverse dimension of class III mandible with and without cleft lip and palate using conical beam tomography

Marina de Almeida Barbosa Mello 22 March 2017 (has links)
A relação entre a anatomia mandibular e a ocorrência de fratura indesejada de mandíbula na osteotomia sagital é alvo de estudos. A literatura mostra a existência de diferentes conformações anatômicas da mandíbula, porém não há estudos nessa área direcionados a indivíduos com fissura labiopalatina. Também não há na literatura estudos que mostrem as diferenças morfológicas da mandíbula relacionadas a secção transversal entre primeiro e segundo molar e sua relação com implicações na cirurgia ortognática. O objetivo do presente estudo foi avaliar a morfologia da região entre primeiro e segundo molar inferior e classificar a prevalência dos tipos mandibulares dentro de cada grupo. Foram realizadas análises e medições das reformatações das tomografias da região de molares, bilateralmente, de indivíduos Classe III, com fissura labiopalatina unilateral (Grupo FLP) submetidos à cirurgia ortognática para recuo mandibular no Hospital de Reabilitação de Anomalias Craniofaciais e de indivíduos Classe III, sem fissura (Grupo Controle) do banco de dados do Departamento de Cirurgia e Estomatologia da Faculdade de Odontologia de Bauru. Foram realizadas duas medidas lineares e uma medida angular. As hemimandíbulas foram classificadas segundo a profundidade da fossa mandibular em: Tipo a - 0 e 1mm; Tipo b - 1,1 e 2mm; Tipo c - 2,1 e 3mm; Tipo d - maior que 3,1mm. Foram analisadas 200 hemimandíbulas no Grupo FLP e 100 no Grupo Controle. Os resultados mostraram que não houve diferença entre os grupos quanto a classificação das mandíbulas segunda a profundidade da fossa, sendo o grupo b o mais prevalente, mas houve diferença em relação a angulação e a altura da mandíbula . Também foi notada uma relação entre a altura da mandíbula e a sua angulação em ambos os grupos. Assim, pode ser observada a grande variação morfológica dessa região, tanto para o grupo com fissura labiopalatina, quanto para o grupo controle. / The relationship between a mandibular anatomy and an occurrence of an undesirable jaw fracture in a sagittal osteotomy is the subject of the studies. The literature shows an existence of different anatomical conformations of the mandible, but there are no studies on the area directed to individuals with cleft lip and palate. There are not in the literature, studies that show a prevalence of mandibular types and the relation of these anatomical variations with orthognathic surgery implications. The objective of the present study was evaluate the morphology of the region between the first and second lower molars and analyze the prevalence of mandibular types within each sample group. Analyzes and measurements of the CT scans were performed bilaterally on Class III patients with unilateral cleft lip and palate (CLP Group) submitted to orthognathic surgery for mandibular retreatment at the Hospital for Rehabilitation of Craniofacial Anomalies and Class III individuals, without Fissure (Control Group) of the database of the Department of Stomatology of the Faculty of Dentistry of Bauru. Two linear measurements and one angular measurement were performed. The half of mandibles were classified according to the depth of the mandibular fossa in: Type a - 0 and 1mm; Type b - 1.1 and 2mm; Type c - 2.1 and 3 mm; Type d - greater than 3.1mm. Two hundred half of mandibles were analyzed in the CLP Group and 100 in the Control Group. The results showed that there was no difference between the groups regarding the classification of the mandibles according to the depth of the fossa, being group b the most prevalent, but there was difference in relation to the angulation and the height of the mandible. It was also noted a relationship between the height of the mandible and its angulation in both groups. Thus, the great anatomical variation of this region can be observed, both for the group with fissure and for the group without fissure.
342

Avaliação do osso alógeno fresco congelado para aumento de rebordo mandibular posterior atrófico. Estudo tomográfico em humanos / Evaluation of fresh frozen bone allograft for atrophic posterior mandible augmentation. Tomographic study in humans

Erick Ricardo Silva 19 January 2016 (has links)
O aumento ósseo de rebordos mandibulares posteriores atróficos continua sendo um grande desafio para os cirurgiões orais. Sabe-se que o osso alógeno pode ser utilizado para realização de enxertos aposicionais nessa região, com bons resultados clínicos e histomorfométricos, porém não há estudos sobre a manutenção óssea volumétrica desses enxertos em longo prazo. O objetivo deste estudo foi avaliar tomograficamente, por meio de medidas lineares e volumétricas, a dinâmica de manutenção do osso alógeno córtico-medular fresco congelado em bloco na cirurgia de aumento ósseo de rebordos mandibulares posteriores atróficos em humanos. Os pacientes do estudo foram submetidos à realização de enxertos aposicionais de osso alógeno fresco congelado em bloco na região posterior mandíbula. Os blocos foram modelados manualmente, fixados aos leitos receptores com parafusos de titânio de 1,5 x 10,0 mm e recobertos com osso mineral bovino e membrana absorvível de colágeno suíno. Para avaliação do ganho ósseo em altura, espessura e volume, cada paciente foi submetido a exames de tomografia computadorizada de feixe cônico (TCFC) em 03 períodos experimentais: imediatamente após a cirurgia de enxerto (T1); 06 meses após a enxertia, no momento de instalação dos implantes (T2) e 01 ano após a carga funcional protética (T3). Os dados obtidos foram tabulados e submetidos à análise estatística por meio do teste de Kruskal-Wallis seguido do post test de Tukey. Para comparação entre dois grupos, foram empregados os testes t de Student e Mann-Whitney. Foram operados 20 pacientes, 15 mulheres e 05 homens, com idade entre 37 e 64 anos (51,8 ± 7,5 anos), para os quais um total de 50 blocos ósseos foi utilizado. Dos 50 blocos, 8% foram utilizados para aumento ósseo em altura, 50% para espessura e 42% para altura e espessura. O ganho ósseo em altura foi de T1 = 5,15 ± 1,04 mm, T2 = 3,91± 0,94 mm e T3 = 2,92 ± 0,71 mm; em espessura, foi de T1 = 6,42 ± 1,20 mm, T2 = 4,64 ± 1,32 mm e T3 = 4,02 ± 0,71 mm. O ganho ósseo em volume foi de T1 = 1176,62 ± 358,08 mm³, T2 = 785,78 ± 201,16 mm³ e T3 = 689,72 ± 187,45 mm³. Foi observada diferença estátistica entre os três tempos experimentais tanto para altura quanto para espessura. Porém, volumetricamente, não foi possível observar diferença entre T2 e T3. No total, foram instalados 50 implantes (01 implante/bloco), para os quais foi obtida uma taxa de sobrevivência de 96% após 31,75 ± 6,99 meses de acompanhamento pós-operatório. Com base nos resultados obtidos, pode-se concluir que o osso alógeno fresco congelado em bloco constitui uma alternativa viável para cirurgia de aumento de rebordo mandibulares posteriores atróficos, apresentando uma manutenção volumétrica aceitável em longo prazo e permitindo a instalação de implantes com alta taxa de sucesso. / Atrophic posterior mandible bone augmentation remains a major challenge for oral surgeons. It is known that allogenic bone can be used for appositional grafts in this region, with good clinical and histomorphometric results, howerer there are no long term studies on the volumetric bone maintenance of these grafts. The objective of this study was to evaluate tomographically, through linear and volumetric measurements, the dynamic maintenance of corticocancellous fresh frozen allograft bone blocks for atrophic posterior mandible augmentation in humans. The patients of the study were submitted to fresh frozen allograft bone block appositional grafting surgery in the posterior mandible. The blocks were manually shaped, fixed to the recipient bed with 1.5 x 10.0 mm titanium screws and covered with bovine bone mineral and porcine collagen absorbable membrane. For assessment of bone gain in height, thickness and volume, each patient underwent cone beam computed tomography (CBCT) at 03 experimental periods: immediately after grafting surgery (T1); 06 months after grafting, at the implant placement (T2) and 01 year after prosthetic functional loading (T3). Data were tabulated and submitted to statistical analysis using the Kruskal-Wallis test followed by Tukey post test. For comparison between two groups, Student t test and Mann-Whitney were employed. Twenty patients were operated, 15 women and 05 men, aged between 37 and 64 years (5.8 ± 7.5 years), for which a total of 50 bone blocks was used. Of the 50 blocks, 8% were used for bone augmentation in height, 50% in thickness and 42% for both height and thickness. The bone gain in height was 5.15 ± 1.04 T1 = mm, T2 = 3.91 ± 0.94 mm and T3 = 2.92 ± 0.71 mm; while in thickness was T1 = 6.42 mm ± 1.20, 4.64 ± T2 = T3 = 1.32 mm and 4.02 ± 0.71 mm. The bone gain in volume was T1 = 1176.62 ± 358.08 mm³, T2 = 785.78 ± 201.16 mm³ and T3 = 689.72 ± 187.45 mm³. Statistical difference was observed between the three experimental times for both height and thickness. However, volumetrically, no difference was observed between T2 and T3. Fifty implants were installed (01 implant/block), with a survival rate of 96% after 31.75 ± 6.99 months of postoperative follow-up. Based on these results, it can be concluded that the fresh-frozen allograft bone block is a viable alternative for atrophic posterior mandible augmentation, presenting an acceptable long-term volumetric bone maintenance and allowing dental implant installation with high success rates.
343

Avaliação anatômica da região posterior da mandíbula por meio de tomografia computadorizada de feixe cônico no planejamento pré-operatório em implantodontia

Souza, Lílian Azevedo de 26 April 2013 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-05-06T13:56:45Z No. of bitstreams: 1 lilianazevedodesouza.pdf: 1138736 bytes, checksum: bbc7a1e539e3c4d2921d503313b5eed5 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-06-07T16:01:03Z (GMT) No. of bitstreams: 1 lilianazevedodesouza.pdf: 1138736 bytes, checksum: bbc7a1e539e3c4d2921d503313b5eed5 (MD5) / Made available in DSpace on 2016-06-07T16:01:03Z (GMT). No. of bitstreams: 1 lilianazevedodesouza.pdf: 1138736 bytes, checksum: bbc7a1e539e3c4d2921d503313b5eed5 (MD5) Previous issue date: 2013-04-26 / O objetivo deste estudo foi avaliar e correlacionar as características anatômicas da região posterior mandibular (profundidade da fossa submandibular, altura e espessura ósseas e corticalização do canal da mandíbula), visando a prevenção de acidentes e um planejamento seguro em Implantodontia. Para isso foram analisados, bilateralmente, quatro cortes parassagitais de 100 exames de tomografia computadorizada de feixe cônico (TCFC). Foram realizadas mensurações lineares da profundidade da fossa submandibular e da altura e espessura ósseas. A corticalização do canal da mandíbula também foi avaliada e classificada. Os resultados indicaram que a profundidade da fossa submandibular e a espessura óssea implantar apresentaram efeitos significativos na variabilidade da amostra. Correlações entre a profundidade da fossa submandibular e a espessura óssea implantar foram observadas. Altura e espessura ósseas implantares mostraram correlação significativa negativa com a idade do paciente. Pode-se concluir que as principais variáveis responsáveis pela variabilidade da amostra foram a profundidade da fossa submandibular e a espessura óssea implantar, sendo que, quanto maior a espessura óssea, maiores foram os valores encontrados de profundidade da fossa submandibular. Fossas submandibulares pronunciadas aumentam o risco de perfuração da cortical lingual, trazendo prejuízos e riscos na instalação de implantes. Os valores de altura e espessura ósseas se correlacionaram de maneira negativa com a idade do paciente, ou seja, quando maior a idade, menores os valores de altura e espessura. Dessa forma, destacou-se a importância da análise dos cortes parassagitais de TCFC na análise e planejamento para implantes na região posterior mandibular, uma vez que, pelas variáveis estudadas, os pacientes apresentam características diferentes, só visualizadas por exame de imagem acurado. / The aim of this study was to evaluate and correlate the anatomical features of the posterior mandibular (submandibular fossa depth, height and thickness of the alveolar bone and mandible canal corticalization), aimed at preventing accidents and insurance planning in implantology. Four parasagittal slices of 100 cone-beam computed tomography (CBCT) were analyzed bilateraly. Linear measurements of depth of the submandibular fossa and height and thickness of the alveolar bone were performed. The mandible canal corticalization was also evaluated and classified. The results indicated that the depth of the submandibular fossa and thickness alveolar bone showed significant effect on the variability of the sample. Correlations between the depth of the submandibular fossa and thickness bone were observed. Height and thickness of the alveolar bone showed significant negative correlation with patient age. It can be concluded that the main variables responsible for the variability of the sample were submandibular fossa depth and thickness alveolar bone, and the higher the bone thickness, higher values were found deep submandibular fossa. Pronunced submandibular fossa increases the risk of perforation of the lingual cortical, causing losses and risks in implant placement. The values of bony height and thickness negatively correlated with age of the patient, i.e. when increasing age, smaller values for height and thickness. Thus, the information obtained in this study were made possible through evaluation CBCT parasagittal slices, validating this exam as an important tool for assessing and planning for the safe installation of implants in the posterior mandible.
344

Visualização da alça anterior do nervo mentual e canal incisivo mandibular : comparação entre radiografia panorâmica e tomografia computadorizada de feixe cônico / Visualization of the anterior loop of the mental nerve and the mandibular incisive cana : comparison between panoramic radiograph and cone beam

Brito, Ana Caroline Ramos de, 1983- 24 August 2018 (has links)
Orientadores: Christiano de Oliveira Santos, Deborah Queiroz de Freitas França / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-24T14:32:39Z (GMT). No. of bitstreams: 1 Brito_AnaCarolineRamosde_M.pdf: 1219025 bytes, checksum: ef2bdb09a94a5029e24c443278f93c29 (MD5) Previous issue date: 2014 / Resumo: Procedimentos cirúrgicos na região anterior de mandíbula estão sujeitos a hemorragias no transcirúrgico ou distúrbios sensoriais no pós-operatório. Para evitar possíveis lesões a vasos e nervos, faz-se necessário uma avaliação cuidadosa dessa região. Achados anatômicos como a alça anterior do nervo mentual (AANM) e o canal incisivo mandibular (CIM) encontram-se na região interforaminal. O objetivo deste estudo foi comparar a apresentação dessas estruturas (AANM e CIM) em radiografias panorâmicas (PAN) e tomografias computadorizadas de feixe cônico (TCFC) e determinar sua extensão anterior ao forame mentual (FM), em PAN e nas reconstruções panorâmica e parassagital da TCFC. A amostra consistiu de imagens de 91 indivíduos que possuíam PAN e TCFC. Foram consideradas as presenças da AANM e do CIM e; quando presentes, mediu-se o comprimento da extensão mesial ao FM, da AANM e/ou CIM, com diâmetro maior ou igual a 1 mm, tanto na PAN quanto na TCFC. Duas medidas mesiais ao FM foram obtidas, tendo dois planos de orientação distintos: 1) na PAN e na reconstrução panorâmica da TCFC, o plano de orientação foi a base da mandíbula; 2) o plano oclusal orientou a contagem dos cortes parassagitais da TCFC, que possuíam 0,25 mm de espessura. A análise estatística dos dados empregou os teste Kappa, ICC, McNamer Bowker, ANOVA com teste de post hoc de Tukey e teste t. Na TCFC, a prevalência da AANM chegou a 53,3% e do CIM a 58,8%. Já na PAN, a frequência de AANM chegou a 23,1% e do CIM a 19,8%. A PAN apresentou maior dificuldade de visualização para as duas estruturas. A extensão anterior ao FM dessas estruturas variou de 1,00 mm (ou 0 mm quando AANM e CIM estavam ausentes) até 19,0 mm, quando observadas na TCFC. A PAN superestimou as medidas em aproximadamente 2,0 mm em média. A grande variação das medidas demonstrou que não é possível determinar uma distância anterior ao FM segura para a instalação de implantes. Considerando as limitações da PAN, recomenda-se o uso da TCFC para avaliações pré-cirúrgicas de implantes, na região anterior de mandíbula, de forma a evitar lesões a vasos e nervos / Abstract: Surgical procedures in the anterior mandible are susceptible to hemorrhage or sensory disturbances in the perioperative or postoperative period. To prevent possible injuries to vessels and nerves a careful assessment of this region is necessary. Anatomical findings such as the anterior loop of the mental nerve (ALMN) and the mandibular incisive canal (MIC) are found in the interforaminal region. The aim of this study was to compare the presentation of these structures (ALMN and MIC) on panoramic radiographs (PAN) and on cone beam computed tomography (CBCT) and to determine its anterior extension to mental foramen (MF), in PAN and in both panoramic reconstructions and cross-section from CBCT exams. The sample consisted of diagnostic images of 91 individuals who had PAN and CBCT. Presence of ALMN and MIC was assessed; when present, the length of mesial extension of ALMN and/or MIC (with diameter greater than 1 mm) from the mental foramen (MF), was measured in both PAN and CBCT. Mesial extension to the MF was measured in two ways: for PAN and CBCT panoramic reconstructions, the plane of orientation was the inferior margin of the mandible; for cross-sections the occlusal plane guided the measurement. The statistical analysis employed the Kappa, ICC, McNamer Bowker, ANOVA with post hoc Tukey test and t test. On CBCT, 53.3% of the hemimandibles showed ALMN and 58.8% showed MIC. Considering PAN, the frequency of ALMN was 23.1% and 19.8% for MIC. PAN presented more difficulties for viewing both structures. The anterior extension to from the MF of these structures ranged from 1.00 mm (or 0 mm when ALMN and MIC were absent) to 19.00 mm, when observed in CBCT. PAN overestimated the measurements by approximately 2.0 mm on average. The measurements showed that it is not possible to determine a safe mesial distance from the MF for implant placement. Considering the limitations of PAN, it is recommended the use of CBCT for pre-surgical assessments of implants in the anterior region of the mandible to avoid potential sensory and hemorrhagic complications / Mestrado / Radiologia Odontologica / Mestra em Radiologia Odontológica
345

Analyses expérimentales et modélisation numérique de l'ostéogenèse au sein d'un implant poreux en titane. / Experimental analysis and numerical model of osteogenesis within a porous titanium scaffold

Schmitt, Mary 16 June 2015 (has links)
Récemment, dans le domaine de la reconstruction tissulaire, des substituts osseux ou scaffold, ont été utilisés comme alternative aux autogreffes. La complexité de l'ostéogenèse au sein d'une structure poreuse rend son observation expérimentale difficile et par conséquent le développement et l'optimisation des scaffolds sont loin d'être achevés. En complément d'expérimentations animales, il est donc nécessaire de développer des modèles numériques afin de mieux comprendre ce processus. L'objectif de ce travail était de développer un modèle numérique capable de reproduire l'ostéogenèse au sein d'un scaffold poreux en titane, implanté sur la partie non dentée d'une hémimandibule de brebis durant 12 semaines. Cette thèse était donc basée sur une approche à la fois expérimentale et numérique, ce qui constituait l'élément clé du projet. En effet, la plupart des modèles existants n'ont pas été validés expérimentalement ou l'ont été à l'aide d'expérimentations réalisées sur de petits animaux (i.e. lapin, rat) puisque leur taille et leur coût facilitaient le protocole. Néanmoins, contrairement au mouton, leurs processus de régénération osseuse sont très éloignés de celui de l'homme. L'étude a été organisée en trois tâches. Tout d'abord, les expérimentations animales ont été réalisées en collaboration avec le Dr Thomas Schouman (Hôpital de la Pitié-Salpêtrière), et OBL, une PME française fabriquant les scaffolds en titane. Puis, un modèle numérique en éléments finis décrivant l'activité cellulaire au sein du scaffold durant les 12 semaines d'implantation a été conçu. Enfin, des examens histologiques et micro-tomographiques et des tests mécaniques réalisés sur chaque hémimandibule explantée ont permis de: i) quantifier le pouvoir ostéo-conducteur du scaffold en titane et ii) valider le modèle numérique d'ostéogénèse. / Recently, in the tissue reconstruction field, bone substitutes or scaffolds have been used as an alternative to autograft. The complexity of osteogenesis within a scaffold makes its experimental observation difficult and the development and optimization of scaffolds are thus far from being complete. In addition to animal experiments, it is then necessary to develop numerical models to better understand such process. The objective of this work was to develop a numerical model able to reproduce osteogenesis within a porous titanium scaffold implanted on the non-toothed part of a ewe hemimandible for 12 weeks. Therefore, this thesis was based on both an experimental and a numerical approach, which constituted the key element of the project. Indeed, most of the existing models have not been validated or have been validated using experiments performed on small animals (i.e. rabbit, rat) since their size and cost make the protocol easier. Nevertheless, unlike the sheep, their bone regeneration process is quite different from human's. The study was organized into three tasks. First, animal experiments were carried out in collaboration with Dr. Thomas Schouman (Pitié-Salpêtrière hospital) and OBL, a french company manufacturing the porous titanium scaffolds. Then, a numerical model describing cellular activity within the scaffold during the 12 weeks of implantation was developed. Finally, histological and micro-tomographic analyses and mechanical tests performed on each hemimandible have enabled to: i) quantify the osteoconductive potential of the scaffold and ii) validate the numerical results.
346

Biomechanical investigation of the mandible, a related donor site and reconstructions for optimal load-bearing

Bujtár, 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.
347

Sledování ontogenetického vývoje mandibuly na základě metod geometrické morfometrie / Evaluation of ontogenetic development of the mandible using geometric morphometric methods

Kiebelová, Alena January 2010 (has links)
During ontogeny there are a lot of changes in the entire human skeleton. This thesis deals with shape changes in the mandible, which are caused by genetic, hormonal, as well as mechanical factors. The most important mechanical factors influencing the shape of mandible are development of deciduous and permanent dentition and also development of masticatory muscles. 34 children mandibles of known age and 14 adult mandibles were analysed and compared for this thesis. Data were obtained by scanning coordinates of 36 landmarks using Microscribe G2X, and then were processed by software PAST and Morphologika2 using multivariate statistics (PCA, MANOVA). Geometric morphometrics is used for a detailed analysis of shape changes of the mandible. There is no difference between dental and chronological age. In conclusion, lower jaw narrows during growth, the body extends more in the region of third molars and the ramus grows mainly in the region of condylar process. Chin prominence also occurs during ontogeny. In the group of adult mandibles the variability is caused by coronoid process height and the body width. The hypothesis, that age groups are significantly different from each other, and therefore due to tooth mineralization there are marked shape changes, is confirmed.
348

Toward Patient Specific Long Lasting Metallic Implants for Mandibular Segmental Defects

Shayesteh Moghaddam, Narges January 2015 (has links)
No description available.
349

Anesthetic Efficacy of a Labial plus Lingual Infiltration Compared to a Labial Infiltration using Articaine in Mandibular Anterior Teeth

Nuzum, Frederick Micah 30 September 2009 (has links)
No description available.
350

Avaliação histológica da reparação óssea em defeitos bicorticais no ângulo de mandíbula de ratos geneticamente hipertensos e de seus controles Wistar-Kyoto / Histological evaluation of bone repair in through-in-through defects of mandibular angle of the spontaneously hypertensive rats and controls Wistar-Kyoto

Chin, Veronica Kei Len 01 October 2008 (has links)
A presença da hipertensão arterial pode comprometer a qualidade da reparação óssea, pois a doença é caracterizada por alterações fisiopatológicas vasculares e do metabolismo mineral. Com o objetivo de avaliar a neoformação e o remodelamento ósseo, este trabalho investigou o processo da reparação óssea em ratos geneticamente hipertensos (SHR) e de seus controles Wistar-Kyoto (WKY). Defeitos bicorticais de 2mm de diâmetro no lado direito e de 5mm no lado esquerdo, foram realizados com trefinas na região do ângulo de mandíbula. Os animais, divididos em grupos de cinco indivíduos cada, foram sacrificados após 2, 3, 5, 10, 15, 30, 60 e 90 dias pós-operatórios; as mandíbulas foram removidas, fixadas em formol a 10%, descalcificadas em ácido fórmico a 20%, incluídas em parafina e as secções histológicas, de 7m de espessura, coradas com hematoxilina e eosina. As imagens foram capturadas com aumento de 40x e a área do defeito mensurada pelo programa de histometria digital Image J versão 1.4. A análise estatística revelou que não houve diferença significante na comparação entre as linhagens WKY e SHR (p = 0,884), independente dos períodos ou lados avaliados; entre períodos, nas linhagens WKY (p = 0,101) e SHR (p = 0,479), independente dos lados avaliados; entre períodos por linhagens no lado direito; e entre linhagens por lados, esquerdo com p = 0,466 e direito com p = 0,689, independente do fator período. Houve diferença estatisticamente significante entre o lado esquerdo e o direito (p < 0,001), independente das linhagens e períodos avaliados; entre os lados por linhagens, WKY e SHR, ambas com p < 0,001; entre períodos por linhagens no lado esquerdo, no qual o grupo WKY de 15 dias apresentou área menor que o grupo WKY de 60 dias e o grupo SHR de 10 dias, e o grupo WKY de 60 dias apresentou área maior que o grupo SHR de 30 dias e SHR de 60 dias. Apesar das alterações encontradas no lado esquerdo, que podem ser atribuídas à remodelação funcional do osso da mandíbula, não houve diferenças significantes na reparação do defeito de 5mm e de 2mm entre ratos espontaneamente hipertensos e de seus controles Wistar-Kyoto. / Arterial hypertension may affect the quality of bone repair because this disease is characterized by physiopathological vascular and bone metabolism changes. With the objective of evaluating the bone neoformation and remodeling, this study investigated the process of bone repair in spontaneously hypertensive rats (SHR) and their match controls Wistar-Kyoto (WKY). Through-in-through defects were done with trephine burs in the mandibular angle area, of 2mm diameter on the right side and 5mm diameter on the left side. The animals were divided into groups of five individuals each one and killed after 2, 3, 5, 10, 15, 30, 60 and 90 postoperative days; the mandibles were removed, fixed in 10% formalin solution, decalcified with 20% formic acid, and embedded in paraffin; the histological sections of 7m thickness were stained with hematoxylin and eosin. The images were captured with 40x magnification and the defect area was measured by the image processing program Image J version 1.4. The statistical analysis showed that there is no significant difference in the comparison of WKY and SHR strains (p = 0,884), independent of periods or sides; among periods, in the WKY strain (p = 0,101) and SHR one (p = 0,479), independent of sides; among periods by strains on the right side; and among strains by sides, left side with p = 0,466 and right side with p = 0,689, independent of periods. There is a significant difference between left and right side (p < 0,001), independent of strains and periods; between sides by strains, WKY and SHR, both with p < 0,001; among periods by strains on the left side, which WKY 15 days group showed an area smaller than WKY 60 days and SHR 10 days groups, and WKY 60 days group showed an area bigger than SHR 30 days and SHR 60 days groups. Despite the changes founded on the left side that could be attributed to the functional remodeling of the mandibular bone, there were no differences in the bone repair of 5mm and 2mm diameter defects between spontaneously hypertensive rats and their match controls Wistar-Kyoto.

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