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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.
201

Rhythmic Masticatory Muscle Activity during Sleep: Etiology and Clinical Perspectives

Carra, Maria Clotilde 06 1900 (has links)
L’activité rythmique des muscles masticateurs (ARMM) pendant le sommeil se retrouve chez environ 60% de la population générale adulte. L'étiologie de ce mouvement n'est pas encore complètement élucidée. Il est cependant démontré que l’augmentation de la fréquence des ARMM peut avoir des conséquences négatives sur le système masticatoire. Dans ce cas, l'ARMM est considérée en tant que manifestation d'un trouble moteur du sommeil connue sous le nom de bruxisme. Selon la Classification Internationale des Troubles du Sommeil, le bruxisme est décrit comme le serrement et grincement des dents pendant le sommeil. La survenue des épisodes d’ARMM est associée à une augmentation du tonus du système nerveux sympathique, du rythme cardiaque, de la pression artérielle et elle est souvent en association avec une amplitude respiratoire accrue. Tous ces événements peuvent être décrits dans le contexte d’un micro-éveil du sommeil. Cette thèse comprend quatre articles de recherche visant à étudier i) l'étiologie de l’ARMM pendant le sommeil en relation aux micro-éveils, et à évaluer ii) les aspects cliniques du bruxisme du sommeil, du point de vue diagnostique et thérapeutique. Pour approfondir l'étiologie de l’ARMM et son association avec la fluctuation des micro-éveils, nous avons analysé le patron cyclique alternant (ou cyclic alternating pattern (CAP) en anglais), qui est une méthode d’analyse qui permet d’évaluer l'instabilité du sommeil et de décrire la puissance des micro-éveils. Le CAP a été étudié chez des sujets bruxeurs et des sujets contrôles qui ont participé à deux protocoles expérimentaux, dans lesquels la structure et la stabilité du sommeil ont été modifiées par l'administration d'un médicament (la clonidine), ou avec l'application de stimulations sensorielles (de type vibratoire/auditif) pendant le sommeil. Dans ces deux conditions expérimentales caractérisées par une instabilité accrue du sommeil, nous étions en mesure de démontrer que les micro-éveils ne sont pas la cause ou le déclencheur de l’ARMM, mais ils représentent plutôt la «fenêtre permissive» qui facilite l'apparition de ces mouvements rythmiques au cours du sommeil. Pour évaluer la pertinence clinique du bruxisme, la prévalence et les facteurs de risque, nous avons effectué une étude épidémiologique dans une population pédiatrique (7-17 ans) qui était vue en consultation en orthodontie. Nous avons constaté que le bruxisme est un trouble du sommeil très fréquent chez les enfants (avec une prévalence de 15%), et il est un facteur de risque pour l'usure des dents (risque relatif rapproché, RRR 8,8), la fatigue des muscles masticateurs (RRR 10,5), les maux de tête fréquents (RRR 4,3), la respiration bruyante pendant le sommeil (RRR 3,1), et divers symptômes liés au sommeil, tels que la somnolence diurne (RRR 7,4). Ces résultats nous ont amenés à développer une étude expérimentale pour évaluer l'efficacité d'un appareil d'avancement mandibulaire (AAM) chez un groupe d'adolescents qui présentaient à la fois du bruxisme, du ronflement et des maux de tête fréquents. L'hypothèse est que dans la pathogenèse de ces comorbidités, il y a un mécanisme commun, probablement lié à la respiration pendant le sommeil, et que l'utilisation d'un AAM peut donc agir sur plusieurs aspects liés. À court terme, le traitement avec un AAM semble diminuer l'ARMM (jusqu'à 60% de diminution), et améliorer le ronflement et les maux de tête chez les adolescents. Cependant, le mécanisme d'action exact des AAM demeure incertain; leur efficacité peut être liée à l'amélioration de la respiration pendant le sommeil, mais aussi à l'influence que ces appareils pourraient avoir sur le système masticatoire. Les interactions entre le bruxisme du sommeil, la respiration et les maux de tête, ainsi que l'efficacité et la sécurité à long terme des AAM chez les adolescents, nécessitent des études plus approfondies. / Approximately 60% of the general adult population experiences rhythmic masticatory muscle activity (RMMA) during sleep. The etiology of this movement is not yet understood. However, it has been demonstrated that an increased frequency of RMMA may have detrimental consequences on the stomatognathic system. In this case, RMMA is considered the manifestation of a sleep-related motor disorder known as sleep bruxism (SB). According to the definition of the International Classification of Sleep Disorders, SB is the activity of tooth grinding and clenching during sleep. The occurrence of SB-related activity, i.e., RMMA, is associated with rises of sympathetic tone, heart rate, blood pressure, and it is frequently concomitant with larger respiratory breaths. All these events can be described within a sleep arousal. The present thesis includes four research articles aimed to study i) the etiology of RMMA during sleep in relation to sleep arousal; and ii) the clinical perspectives of SB assessment and management. To further investigate the etiology of RMMA and its association with sleep arousal fluctuations we analyzed the cyclic alternating pattern (CAP), a scoring method to assess sleep instability and describe sleep arousal pressure. CAP was scored in SB subjects and controls that participated in two experimental protocols in which sleep architecture and stability were altered by either a medication (i.e., clonidine), or sensory stimulations (i.e., vibratory/auditory). Under these experimental conditions known to increase sleep instability, we were able to show that sleep arousal is not the trigger or cause of RMMA, rather the “permissive window” that facilitates the occurrence of RMMA during sleep. To evaluate the clinical relevance of SB, we conducted a survey on a 7-17 year old orthodontic population to investigate the prevalence and risk factors associated with SB. It appeared that SB is a highly prevalent sleep disorders in children (15% of prevalence), and is a risk factor for tooth wear (odds ratio, OR 8.8), jaw muscle fatigue (OR 10.5), frequent headache (OR 4.3), loud breathing during sleep (OR 3.1), and several sleep complaints, such as daytime sleepiness (OR 7.4). These findings led us to design an experimental trial using a mandibular advancement appliance (MAA) in adolescents in order to investigate the possible relationship between SB, snoring, and headache. We hypothesized that a common underlying mechanism related to breathing during sleep may be responsible for all concomitant conditions. The short-term use of an MAA appeared to reduce SB (up to 60%), and improve snoring and headache complaints in adolescents. However, the precise mechanism of action of MAA remains under debate; its effectiveness can be either related to the improvement of breathing during sleep, or its influence on the masticatory system. The interactions between SB, breathing, and headache as well as the long-term effectiveness and safety of the MAA in adolescents need further investigations. / L’attività ritmica dei muscoli masticatori (ARMM) durante il sonno si osserva in circa il 60% della popolazione generale adulta. L'eziologia di questo movimento non è stata ancora del tutto compresa. Tuttavia, è dimostrato che un’aumentata frequenza di ARMM può avere conseguenze negative sul sistema stomatognatico. In questo caso, l’ARMM è considerato la manifestazione di un disturbo motorio del sonno noto come bruxismo. Secondo la Classificazione Internazionale dei Disturbi del Sonno, il bruxismo è l'attività di digrignamento e serramento dei denti durante il sonno. La comparsa di episodi di ARMM durante il sonno è associata a un aumento del tono del sistema nervoso simpatico, della frequenza cardiaca, della pressione arteriosa, ed è spesso in concomitanza con un aumentato volume inspiratorio. Le variazioni di questi parametri fisiologici sono compresi nel contesto di un arousal (micro risveglio) del sonno. Questa tesi comprende quattro articoli di ricerca volti a studiare i) l'eziologia dell’ARMM durante il sonno in relazione all’arousal, ed a valutare ii) l’inquadramento clinico del bruxismo nel sonno. Per approfondire l'eziologia dell’ARMM e l’associazione con l’arousal nel sonno, abbiamo analizzato il cyclic alternating pattern (CAP), che permette di valutare l'instabilità del sonno e descrivere la potenza degli arousals. Il CAP è stato esaminato in soggetti con bruxismo e soggetti controllo che hanno partecipato in due protocolli sperimentali, in cui la struttura e la stabilità del sonno sono stati modificati con la somministrazione di un farmaco (la clonidina), o con l’applicazione di stimolazioni sensoriali (di tipo vibratorio/uditivo) durante il sonno. In queste condizioni sperimentali caratterizzate da un’aumentata instabilità del sonno, siamo stati in grado di dimostrare che l’arousal non è la causa o il generatore dell’ARMM, ma piuttosto la "finestra permissiva" che facilita il verificarsi di questi movimenti ritmici durante il sonno. Per valutare la rilevanza clinica del bruxismo, abbiamo condotto uno studio epidemiologico in una popolazione pediatrica afferente alla clinica di ortodonzia per studiare la prevalenza e i fattori di rischio associati al bruxismo. Questa ricerca ha evidenziato che il bruxismo è un comune disturbo del sonno nei bambini (con una prevalenza del 15%), ed è un fattore di rischio per usura dentale (odds ratio, OR 8.8), fatica dei muscoli masticatori (OR 10.5), mal di testa frequenti (OR 4.3), respirazione rumorosa durante il sonno (OR 3.1), e diversi sintomi legati al sonno, quali la sonnolenza diurna (OR 7.4). Questi risultati ci hanno portato a progettare uno studio sperimentale per valutare l’efficacia di un apparecchio di avanzamento mandibolare (AAM) in un gruppo di adolescenti che presentavano al contempo bruxismo, russamento e frequenti cefalee. L’ipotesi è che nella patogenesi di tali comorbidità, vi sia un meccanismo comune, probabilmente legato alla respirazione durante il sonno, e che l’utilizzo di un AAM possa quindi avere un beneficio multiplo. Il trattamento a breve termine con un AAM sembra diminuire l’ARMM (fino al 60%) e migliorare il russamento e i mal di testa negli adolescenti. Tuttavia, l'esatto meccanismo di azione degli AAM rimane incerto; la loro efficacia può essere correlata sia al miglioramento della respirazione durante il sonno, ma anche all’influenza che questi apparecchi svolgono sul sistema masticatorio. Le interazioni tra il bruxismo nel sonno, la respirazione, e le cefalee, così come l'efficacia e la sicurezza a lungo termine degli AAM negli adolescenti, necessitano di ulteriori studi clinici.
202

Virginia Carter Smith: Her Career and Contributions to Advancement in Higher Education

Russell, Kimberly A. 05 1900 (has links)
Most research studies of women in the college and university advancement profession measure the number of women in advancement positions, report their corresponding salaries and reflect on the differences between male and female employees in the same position. Little research explores how women achieve high ranking advancement positions and very few provide an analysis of the characteristics, influences and careers of successful female advancement professionals. This dissertation describes the life and work of Virginia Carter Smith, founding editor of the Council for Advancement and Support of Education's award winning publication CURRENTS. The career and contributions of Virginia Carter Smith are relevant and helpful to advancement professionals in colleges, universities and K-12 institutions. This study explores Smith's formative years as a child, describes her educational and extra-curricular preparation and identifies individuals who influenced her life and provided direction for her future. It also examines Smith's role in the formation and direction of CASE and CURRENTS. Smith successfully launched CURRENTS in 1975 when few women held senior-level positions in advancement-related fields. With Smith's contributions, CASE became the dominate professional organization for advancement professionals working in educational institutions, and CURRENTS continues to be an exemplary professional development periodical for individuals working in advancement. This study also examines how Smith promoted qualified individuals, particularly women, to senior-level positions in colleges and university advancement offices. Hundreds of women and men in the profession claim that Smith's served as a role model or mentor to them. Smith contributed to the increase of women in advancement offices nationally over the last twenty years. Her high standards for herself and for other development officers helped professionalize the field for everyone.
203

"Lilla gumman, du är ändå inte stark" : En studie av hur kvinnliga poliser upplever att de blir bemötta av samhället. / "Honey, you are not strong enough" : A study of how female police officers experiencing that they are being treated by society.

Anwar, Ashna, Lachonius, Lovisa January 2019 (has links)
”Snutfitta”, ”du är ändå inte stark”, ”lilla gumman” är bara några av de förekommande meningar som kvinnliga poliser möts av när de arbetar ute i samhället och möter allmänheten. Att vara kvinna i ett traditionellt sätt mansdominerat yrke kan vara svårt både när det gäller hur de blir behandlade och bemötta samt möjligheten att klättra inom organisationen. Syftet med föreliggande studie var att ta reda på hur kvinnliga poliser upplever att de blir bemötta av samhällets medborgare, men även på arbetsplatsen. Finns det en större press på kvinnor i ett mansdominerat yrke att prestera hårdare för att bevisa att de räcker till? I studien har Erving Goffmans teori om intrycksstyrning, Axel Honneths teori om de tre dimensionerna, Jean Lipman Blumens teori om homosocialitet och heterosocialitet samt Morrisons teori om glastaket tillämpats. Dessa teorier har tillämpats i syfte till att besvara studiens frågeställningar. Resultatet av denna studie presenteras av semistrukturerade intervjuer i en kvalitativ design, där tio kvinnliga poliser deltagit i intervjun och delat med sig av sina upplevelser. Analysen av resultatet visade med hjälp av teorier och vetenskapliga artiklar att det är ett hårdare klimat för kvinnor i ett mansdominerat yrke, dels vad gäller utvecklingsmöjligheter, dels hur kvinnor inom yrket bemöts av samhället. Slutsatsen av resultat och analys visade att även om jämställdheten inom polisyrket ökar, finns det fortfarande skillnader mellan könen vilket grundar sig långt bak i historien och är svårt att komma ifrån / "You are not strong enough" and "honey" are just some of the prevailing sentences that female police officers meet when they work in the community and meet the public. Being a woman in a male-dominated profession can be difficult when it comes to how they are treated and the opportunity to climb within the organization. The purpose of the present study was to find out how female police officers perceive that they are being treated by society's citizens, but also in the workplace. In the study, Erving Goffman's theory of impression management, Axel Honneth's theory of the three dimensions, Jean Lipman Blumen's theory of homosociality and heterosociality, and Morrison's theory of glass ceiling have been applied. These theories have been applied in order to answer the study's questions. The result of this study is presented by semi-structured interviews in a qualitative design, where ten female police officers participated in the interview and shared their experiences. The analysis of the results showed, with the aid of theories and scientific articles, that it is a harder climate for women in a male-dominated profession, both in terms of development opportunities and partly how women within the profession are treated by the society. The conclusion of the result and analysis showed that even though gender equality in the police profession is increasing, there are still differences between the sexes, which is based far behind in history and is difficult to get away from.
204

Estudo biomecânico de tração (ex-vivo) em osteotomia da tuberosidade tibial de cães estabilizada com placa fixa por \"garfo\" ou parafuso / Biomechanical study of traction (ex-vivo) on the tibial tuberosity osteotomy in dogs stabilized with plates fixed by \"fork\" or screws

Ito, Kelly Cristiane 09 November 2012 (has links)
Avanço da tuberosidade tibial (ATT) é uma das técnicas para tratamento da ruptura do ligamento cruzado em cães desenvolvida por Montavon, Damur e Tepic (2002). O sucesso da técnica em reduzir ou eliminar as forças de deslocamento cranial da tíbia em joelhos com ruptura do ligamento cruzado cranial tem sido documentado em estudos experimentais e clínicos. No período pós-operatório a técnica, a falha do implante é relatada em 1 a 5% dos membros pélvicos operados. Este número foi atribuído a erro de técnica ou desenho inicial do implante que foi considerado insuficiente. Com objetivo de comparar a resistência biomecânica entre duas diferentes placas de ATT e minimizar a incidência de falhas de implante, foram realizados ensaios biomecânicos em 10 pares de membros pélvicos de cadáveres cães, no membro pélvico direito placa fixa por garfo e no membro pélvico esquerdo placa fixa por parafusos. Os ensaios foram realizados utilizando-se máquina universal de ensaios mecânicos Kratos® modelo 5002, dotada de célula de carga de 3000N com uma velocidade de ensaio de 20 mm/min. O parâmetro força e os gráficos gerados foram gravados por meio de sistema de aquisição analógica TRACOMP-W95 (TRCV61285). A média da carga máxima até a falha foi de 128,70 Kg/F (mínimo 104,55 Kg/F e máximo 151,80 Kg/F) e de 141,99 Kg/F (mínimo 111,60 Kg/F e máximo 169,65 Kg/F) no grupo utilizando \"garfo\" e parafusos respectivamente. O desvio padrão dos grupos \"garfo\" e parafuso foi baixo, 12,99 e 17,21 respectivamente. Foi encontrada diferença significativa (p = 0,0309) entre as médias dos grupos. / Tibial tuberosity advancement (TTA) is one of the techniques for treatment of cruciate ligament rupture in dogs developed by Montavon, Damur and Tepic (2002). The success of the technique in reducing or eliminating the forces of cranial tibial displacement in knees with ruptured cranial cruciate ligament as been documented in experimental and clinical studies. In the post-operative technique, implant failure is reported in 1-5% of hindlimbs operated. This number was attributed to technical error or the initial design of the implant that was considered insufficient. To compare the biomechanical strength between two different plates ATT and minimize the incidence of implant failures, biomechanical tests were performed on 10 pairs of hindlimbs cadaver dogs, the right hindlimb fixed plate and a fork in the left pelvic limbplate fixed by screws. As says were performed using a universal mechanical testing Kratos ® model 5002, equipped with a load cell of 3000N with a test speed of 20 mm / min. The strength parameter and graphs generated were recorded via analog acquisition system TRACOMP-W95 (TRCV61285). The mean load to failure was 128.70 kg/F (minimum 104.55 Kg and maximum 151.80 Kg/F) and 141.99 Kg/F (minimum 111.60 Kg/F and maximum 169.65 Kg/F) in the group using \"fork\" and screws respectively. The standard deviation of the groups \"fork\" and bolt was low, 12.99 and 17.21 respectively. Significant difference (p = 0.0309) between the means of the groups.
205

Avaliação cefalométrica comparativa dos efeitos do aparelho de protração mandibular em adultos e adolescentes / Mandibular protraction appliance (MPA) effects in adolescents and adults: a cephalometric comparison

Furquim, Bruno D'Aurea 09 February 2009 (has links)
Este estudo retrospectivo teve como objetivo comparar os efeitos esqueléticos, dentários e tegumentares do tratamento com Aparelho de Protração Mandibular (APM) em conjunto com o aparelho fixo em pacientes adolescentes e adultos com má oclusão de Classe II. A amostra foi composta por telerradiografias pré e póstratamento de 23 adolescentes (idade inicial média de 11,75 anos) e de 16 adultos (idade inicial média de 22,41 anos). Testes t (P < 0,05) foram empregados para comparação dos grupos. Os adultos apresentaram menor quantidade de alterações esqueléticas. Com relação às alterações dentárias, os adultos apresentaram menor inclinação lingual dos incisivos superiores; menor extrusão dos incisivos inferiores; menor extrusão dos molares superiores e inferiores; menor mesialização dos molares inferiores; e menor retrusão do lábio superior em comparação aos adolescentes. / The aim of this retrospective study was to compare the skeletal, dental, and soft tissue effects of the Mandibular Protraction Appliance (MPA) treatment in adolescent and adult Class II malocclusion patients. The sample comprised pretreatment and posttreatment cephalograms of 23 adolescents (mean pretreatment age 11.75 years) and 16 adults (mean pretreatment age 22.41 years). The groups were compared with t tests, at P < 0.05. The amount of skeletal changes was smaller in the adult group. Adults showed smaller maxillary incisors lingual tipping, mandibular incisor and molar and maxillary molar extrusion and mandibular molar mesialization. Additionally, adults also showed greater upper lip retrusion as compared to adolescents.
206

Avaliação das alterações nas vias aéreas superiores através de tomografia computadorizada Cone-Beam em pacientes submetidos à cirurgia ortognática de avanço bimaxilar / Three-dimensional upper airway space changes after bimaxillary advancement by Cone-Beam Computed Tomography

Rocha, Thais Lima 11 May 2016 (has links)
Introdução: O descontentamento com a estética facial é considerado o fator motivador mais frequente na procura pela cirurgia ortognática, visto que este é o procedimento indicado nos casos de severas discrepâncias dentoesqueléticas em pacientes adultos. A anatomia das vias aéreas superiores (VAS) permite que fatores como obesidade, hipotonia muscular e deficiência mandibular favoreçam sua obstrução, podendo gerar a Apneia Obstrutiva do Sono (AOS), caracterizada por episódios recorrentes de obstrução parcial ou completa das VAS durante o sono. As cirurgias de avanço bimaxilar estão associadas ao aumento do espaço aéreo, no entanto, as alterações morfológicas e volumétricas ainda não são bem conhecidas. Objetivos: Avaliar as alterações em 3D do espaço aéreo faríngeo frente aos procedimentos de cirurgia ortognática de avanço bimaxilar em pacientes Classe I e II esqueléticos. Material e Métodos: A análise da área axial mínima e do volume da aérea superior foi realizada em pré-operatório (T0) e pós-operatório (T1) de 56 pacientes, sendo 21 do sexo masculino e 35 do sexo feminino, com média de idade de 35,8 (±10,7) anos, submetidos ao avanço bimaxilar pela técnica da osteotomia sagital de mandíbula bilateral associada ao avanço de maxila por meio de osteotomia Le Fort I. As avaliações foram feitas através de tomografia computadorizada Cone-beam, utilizando-se o Programa Dolphin Imaging 11.7. Foi utilizado o teste t pareado para comparar os dados pré e pós-operatórios. Todos os testes foram realizados com o programa Statistica, adotando-se um nível de significância de 5%. Resultados: No estudo do erro do método, não houve erro casual nem sistemático entre a primeira e a segunda medição das variáveis (p >0,05 em todas as medidas). A cirurgia de avanço bimaxilar apresentou uma média de 73,6% (± 74,75%) de aumento volumétrico e 113,5% (±123,87%) de aumento na área axial mínima. Conclusões: Podemos concluir que a cirurgia de avanço bimaxilar proporciona um aumento volumétrico significativo no espaço aéreo superior, bem como na área axial mínima, no entanto, esse ganho nem sempre ocorre na mesma magnitude para todos os pacientes. / Introduction: Facial aesthetics dissatisfaction is considered the most common motivating factor in the search for orthognathic surgery. This procedure may be used in cases of severe dental and skeletal discrepancies in adult patients. The restricted space anatomy of the upper airway space (UAS) allows features such as obesity, muscular hypotonia and mandibular deficiency favor clogging, which may lead to obstructive sleep apnea (OSA), characterized by recurrent episodes of partial or complete obstruction of the UAS during sleep. Surgeries of bimaxillary advancement are associated with increased UAS, however, the morphological and volumetric changes are not well known. Objectives: to evaluate changes in 3D pharyngeal airway in front of orthognathic surgery procedures of skeletal Class I and II subjects. Material and Methods: 3D pharyngeal airway was evaluated preoperative (T0) and postoperative (T1), with the aid of the analysis of the minimum axial area and airway volume. Fifty-six patients 21 male and 35 female, with a mean age of 35.8 (± 10.7) years undergo bimaxillary advancement by the technique of bilateral sagittal split osteotomy of the mandible associated with maxillary advancement through Le Fort I osteotomy. Measurements were made using Cone-beam Computed Tomography, using the Dolphin Imaging program 11.7. Paired t test was used to compare to the data between T0 and T1. All tests were performed with the Statistica Program, adopting a 5% significance level. Results: In the method error of the study, there was no casual or systematic error between the first and second measurement variables (p > 0.05 for all measures). The bimaxillary advancement surgery showed an average of 73.6% (± 74.75%) of increase in volume and 113.5% (±123.87%) increase in the minimum axial area. Conclusions: We concluded that the maxillomandibular advancement surgery provides a significant increase in volume in the UAS as well as the minimum axial area; however, this gain is not always in the same magnitude for all patients.
207

Avaliação cefalométrica comparativa dos efeitos do aparelho de protração mandibular em adultos e adolescentes / Mandibular protraction appliance (MPA) effects in adolescents and adults: a cephalometric comparison

Bruno D'Aurea Furquim 09 February 2009 (has links)
Este estudo retrospectivo teve como objetivo comparar os efeitos esqueléticos, dentários e tegumentares do tratamento com Aparelho de Protração Mandibular (APM) em conjunto com o aparelho fixo em pacientes adolescentes e adultos com má oclusão de Classe II. A amostra foi composta por telerradiografias pré e póstratamento de 23 adolescentes (idade inicial média de 11,75 anos) e de 16 adultos (idade inicial média de 22,41 anos). Testes t (P < 0,05) foram empregados para comparação dos grupos. Os adultos apresentaram menor quantidade de alterações esqueléticas. Com relação às alterações dentárias, os adultos apresentaram menor inclinação lingual dos incisivos superiores; menor extrusão dos incisivos inferiores; menor extrusão dos molares superiores e inferiores; menor mesialização dos molares inferiores; e menor retrusão do lábio superior em comparação aos adolescentes. / The aim of this retrospective study was to compare the skeletal, dental, and soft tissue effects of the Mandibular Protraction Appliance (MPA) treatment in adolescent and adult Class II malocclusion patients. The sample comprised pretreatment and posttreatment cephalograms of 23 adolescents (mean pretreatment age 11.75 years) and 16 adults (mean pretreatment age 22.41 years). The groups were compared with t tests, at P < 0.05. The amount of skeletal changes was smaller in the adult group. Adults showed smaller maxillary incisors lingual tipping, mandibular incisor and molar and maxillary molar extrusion and mandibular molar mesialization. Additionally, adults also showed greater upper lip retrusion as compared to adolescents.
208

Avaliação das alterações nas vias aéreas superiores através de tomografia computadorizada Cone-Beam em pacientes submetidos à cirurgia ortognática de avanço bimaxilar / Three-dimensional upper airway space changes after bimaxillary advancement by Cone-Beam Computed Tomography

Thais Lima Rocha 11 May 2016 (has links)
Introdução: O descontentamento com a estética facial é considerado o fator motivador mais frequente na procura pela cirurgia ortognática, visto que este é o procedimento indicado nos casos de severas discrepâncias dentoesqueléticas em pacientes adultos. A anatomia das vias aéreas superiores (VAS) permite que fatores como obesidade, hipotonia muscular e deficiência mandibular favoreçam sua obstrução, podendo gerar a Apneia Obstrutiva do Sono (AOS), caracterizada por episódios recorrentes de obstrução parcial ou completa das VAS durante o sono. As cirurgias de avanço bimaxilar estão associadas ao aumento do espaço aéreo, no entanto, as alterações morfológicas e volumétricas ainda não são bem conhecidas. Objetivos: Avaliar as alterações em 3D do espaço aéreo faríngeo frente aos procedimentos de cirurgia ortognática de avanço bimaxilar em pacientes Classe I e II esqueléticos. Material e Métodos: A análise da área axial mínima e do volume da aérea superior foi realizada em pré-operatório (T0) e pós-operatório (T1) de 56 pacientes, sendo 21 do sexo masculino e 35 do sexo feminino, com média de idade de 35,8 (±10,7) anos, submetidos ao avanço bimaxilar pela técnica da osteotomia sagital de mandíbula bilateral associada ao avanço de maxila por meio de osteotomia Le Fort I. As avaliações foram feitas através de tomografia computadorizada Cone-beam, utilizando-se o Programa Dolphin Imaging 11.7. Foi utilizado o teste t pareado para comparar os dados pré e pós-operatórios. Todos os testes foram realizados com o programa Statistica, adotando-se um nível de significância de 5%. Resultados: No estudo do erro do método, não houve erro casual nem sistemático entre a primeira e a segunda medição das variáveis (p >0,05 em todas as medidas). A cirurgia de avanço bimaxilar apresentou uma média de 73,6% (± 74,75%) de aumento volumétrico e 113,5% (±123,87%) de aumento na área axial mínima. Conclusões: Podemos concluir que a cirurgia de avanço bimaxilar proporciona um aumento volumétrico significativo no espaço aéreo superior, bem como na área axial mínima, no entanto, esse ganho nem sempre ocorre na mesma magnitude para todos os pacientes. / Introduction: Facial aesthetics dissatisfaction is considered the most common motivating factor in the search for orthognathic surgery. This procedure may be used in cases of severe dental and skeletal discrepancies in adult patients. The restricted space anatomy of the upper airway space (UAS) allows features such as obesity, muscular hypotonia and mandibular deficiency favor clogging, which may lead to obstructive sleep apnea (OSA), characterized by recurrent episodes of partial or complete obstruction of the UAS during sleep. Surgeries of bimaxillary advancement are associated with increased UAS, however, the morphological and volumetric changes are not well known. Objectives: to evaluate changes in 3D pharyngeal airway in front of orthognathic surgery procedures of skeletal Class I and II subjects. Material and Methods: 3D pharyngeal airway was evaluated preoperative (T0) and postoperative (T1), with the aid of the analysis of the minimum axial area and airway volume. Fifty-six patients 21 male and 35 female, with a mean age of 35.8 (± 10.7) years undergo bimaxillary advancement by the technique of bilateral sagittal split osteotomy of the mandible associated with maxillary advancement through Le Fort I osteotomy. Measurements were made using Cone-beam Computed Tomography, using the Dolphin Imaging program 11.7. Paired t test was used to compare to the data between T0 and T1. All tests were performed with the Statistica Program, adopting a 5% significance level. Results: In the method error of the study, there was no casual or systematic error between the first and second measurement variables (p > 0.05 for all measures). The bimaxillary advancement surgery showed an average of 73.6% (± 74.75%) of increase in volume and 113.5% (±123.87%) increase in the minimum axial area. Conclusions: We concluded that the maxillomandibular advancement surgery provides a significant increase in volume in the UAS as well as the minimum axial area; however, this gain is not always in the same magnitude for all patients.
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Efeitos do tratamento da síndrome da apneia obstrutiva do sono com aparelho de avanço mandibular em pacientes idosos, desdentados, em uso de próteses dentárias removíveis / Effects on the treatment of Obstructive Sleep Apnea Syndrome with a Mandibular Advancement Device in edentulous elderly patients wearing removable dental prosthesis

Silveira, Isabele Trigueiro de Araújo Creazzola 03 September 2012 (has links)
O avançar da idade é reconhecidamente um fator de risco para a Síndrome da Apneia Obstrutiva do Sono (SAOS). O motivo dessa constatação está associado à diminuição do tônus da musculatura orofaringeana e à redução da Dimensão Vertical de Oclusão (DVO), esta última atribuída às perdas dentárias. A abordagem odontológica, no tratamento da SAOS, refere-se ao uso de Aparelho de Avanço Mandibular (AAM), que impede a obstrução, parcial ou total, da passagem do ar pela via respiratória alta, durante o sono. Os pacientes desdentados, no entanto, têm sido negligenciados, nos estudos atualmente realizados. Pelo exposto, este trabalho objetivou avaliar os efeitos do tratamento em variáveis polissonográficas, ronco, sonolência, qualidade do sono e ainda os efeitos colaterais pelo uso do AAM titulável, em pacientes idosos e desdentados portadadores de SAOS. A metodologia envolveu inicialmente, cinquenta pacientes, dos quais dezesseis realizaram polissonografia de noite inteira, com gravação do ronco, por meio de um Roncômetro, visando investigação objetiva do sono. Analisaram-se subjetivamente frequência e intensidade do ronco, por questionários. A Escala Visual Analógica de Ronco (EVAR), aplicada ao parceiro de quarto, permitiu, igualmente, que fosse avaliada a intensidade desse sintoma. A sonolência diurna foi quantificada pela Escala de Sonolência de Epworth e a qualidade do sono, pelo Índice de Qualidade do Sono de Pittsburgh. Confecção individualizada dos AAMs respeitou os princípios biológicos relativos à DVO. Durante uma semana após a instalação, os pacientes utilizavam o AMM sem qualquer avanço mandibular, visando redução de quaisquer desconfortos. Subsequentemente, o protocolo estabelecia titulação gradual e progressiva (30%, 50% e 70%) do aparelho. Transposta a etapa de adaptação, após um período superior a quinze dias, as avaliações iniciais foram repetidas Os efeitos colaterais pelo uso do AAM e adesão ao tratamento foram investigados, a partir de questionários. Doze pacientes completaram o estudo (83,3% mulheres), sendo a media de idade 68 anos e índice de massa corporal médio de 28,3 kg/m2. Os resultados permitiram observar reduções significantes no índice de dessaturação de O2 (17,710,1 eventos/h, p=0,05) e índice de apneia (3,10,9 eventos/h, p=0,02). O uso do AAM evidenciou também diminuições na latência do sono REM, movimentos períodicos de perna, saturação mínima de O2, índice de apneia e hipopneia, na posição supina (p>0,05). O estudo objetivo do ronco apontou redução de 49,522,6 eventos/h (p=0,07). Além do mais, as avaliações subjetivas de frequência (p=0,024) e intensidade (p=0,007) do ronco, EVAR (p=0,003), qualidade do sono (p=0,008), efeitos colaterais e adesão ao AAM foram estatisticamente significantes. Foi possível concluir pela eficácia do tratamento sobre algumas variáveis polissonográficas estudadas, parâmetros subjetivos do ronco e qualidade do sono. Ademais, os sintomas relatados, pelo uso do AAM, reduziram-se ao longo do tempo, o que permitiu, com vantagem, que houvesse maior adesão ao tratamento por parte dos pacientes inseridos nesta pesquisa. / Aging process is well known as a risky factor to Obstructive Sleep Apnea Syndrome (OSAS). Concomitant with this process, the reduction of orofacial and pharyngeal musculature tone, as well as the decrease of Vertical Occlusion Dimension (VOD), the latter attributed to tooth loss, have been considered as probable causal agents involved in OSAS pathogenesis. The Dentistry approach for OSAS treatment is commonly related to the use of Mandibular Advancement Devices (MAD), which could prevent partial or complete upper airway obstruction during sleep. However, this treatment has been scarcely used in toothless patients. The aim of this study was to assess the effects of a titratable MAD in polysomnographic (PSG) variables, snoring, sleepiness, sleep quality and side effects, in edentulous elderly patients with OSAS. Sixteen out of fifty patients assessed have been selected and have undergone an overnight polysomnographic study. Snoring was recorded by using suitable equipment, so that an objective assessment of sleep patterns could be made. The frequency and intensity of snoring have also been subjectively assessed by means of questionnaires. The Snoring Visual Analogic Scale (SVAS), posed to a bed partner, was also assessed to evaluate snoring intensity. Excessive daytime sleepiness and the quality of sleep have also been investigated by Epworth Sleepiness Scale and Pittsburgh Sleep Quality Index, respectively. The patients went through the whole process for individually manufacturing of the MAD following the biological principles of the VDO. A week after using the MAD, at 0% of mandibular advancement, the patients were invited to return in order to undergo a new evaluation according to their adaptation to MAD. Subsequently, a titration protocol was gradually established at 30%, 50% and 70% for mandibular advancement. After a period of at least fifteen days, which should correspond to an adjustment of patients to their devices, the same initial assessment procedures were repeated. The MAD collateral effects as well as the treatment acceptance have been investigated through questionnaires. Twelve patients (83,3% females) completed the study, with an average age of 68 years, body mass index of 28,3 kg/m2. The results showed a significant reduction in O2 desaturation index (17,710,1 event/h, p=0,05) and also in AI (3,10,9 events/h, p=0,02). The use of the MAD also represented reductions in the latency to REM sleep, periodical leg movements, minimum O2 saturation, apnea and hypopnea index (AHI) in supine position (p>0,05). The objective assessment of snoring showed a reduction, with no statistical relevance of the Snoring Index (49,522,6 events per hour of recording, p=0,07). The subjective assessment of frequency (p=0,024) and intensity of snoring (p=0,007), EVAR (p=0,003), sleep quality (p=0,008) and the MAD collateral effects as well as the treatment acceptance were also statistically significant. We observed that the OSAS treatment with MAD was effective in some polysomnografic variables studied as well as in the subjective parameters of snoring and sleep quality in edentulous elderly patients. The reported symptoms due to MAD use decreased over the time.
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Re-surface : the novel use of deployable and actively-bent gridshells as reusable, reconfigurable and intuitive concrete shell formwork

Tang, Gabriel Jin-Peng January 2018 (has links)
Following a well-documented rise in the popularity of concrete shell application in the 20th century, thin concrete shells have experienced a global decline despite their potential as efficient structures with an economy of material use with aesthetics benefits. This phenomenon is subject to geographically determined socio-economic conditions and competition from other building solutions as a result of technological advancement in alternative construction systems. Importantly, their decline was attributed to limitations inherent to concrete shell formwork and construction methods. Being able to produce efficient shaping did not ensure that this method of construction is most cost efficient as it still remains difficult to construct double curved surfaces. The thesis addresses the limitations associated with past and present concrete shell building by proposing the use of actively-bent gridshells as re-configurable and reusable formwork for concrete shells to be designed and built. The hypothesis uses deployable scissor-jointed actively-bent gridshells as re-configurable and reusable formwork for concrete shell construction. This was developed from a series of Flash research (Benjamin, 2012) as student construction workshops to investigate the design and creation of actively-bent gridshells held between December 2008 and March 2011 in Sheffield. In this study, to understand this new system, scaled models of actively-bent gridshells were used as preliminary design aid. Deployed into three dimensional forms from a flexible flat grid mat, the structures were rigidized by bracing through triangulation restraints. The temporary rigid structure was subsequently enveloped with fabric onto which concrete was applied to create the concrete shell, thus acting as formwork. This formwork was then removed following the curing of the concrete cast to be reused repeatedly, or reconfigured into another concrete shell form. Hence, the thesis draws on the concepts, principles and ideas pertaining to three key architectural technologies: 1. concrete shell, 2. actively-bent gridshells and 3.fabric formwork. The thesis then presents a series of four prototype concrete shells constructed from different materials spanning between 1.3 meters and 2.45 meters in the workshops at the University of Edinburgh built between August 2014 and September 2015. For each experimental construction, the process of gridshell construction, fabric formwork preparation, concrete casting, gridshell formwork decentring and different design elements of openings, edges and anchorage abutments were analysed and discussed under the themes of construction, architectural tectonics and structure. The tectonic of process and material is understood and discussed based on the idea of stereogeneity (Manelius, 2012). Specifically, the relationship between gridshell as formwork and the concreting process was studied, analysed and assimilated in concrete shells built with progressive sophistication and elegance, culminating in a doubly-curved concrete shell that demonstrated both synclastic and anticlastic geometries, with further abutment simplification, edge leaning and physical openings incorporation. The study concludes with a physical concrete shell model formed by applying concrete onto fabric formwork to cover the Weald and Downland Jerwood gridshell. In the 1:20 scaled model, the proposed method is speculatively applied onto fabric stretched between pre-determined curvatures of the as-built gridshell. This formwork was subsequently removed for reuse, re-deployed and reconfigured. Using finite element analysis, the structural behaviour of the gridshell made of glass-fibre reinforced tubes and structural characteristics of the resultant concrete shell was checked. The interaction between the three technologies are discussed architectonically and structurally to inform guidelines for potential life-scale application. The thesis evidences the feasibility of the proposed system. It re-purposes a scaled model of a deployable gridshell as a physical modelling tool to facilitate concrete shell design, for both pure compression shells and "improper" shells, demonstrating its adaptability. It also promotes and reinvigorates concrete shells as possible architectural systems serving to instigate future research to revive concrete shell construction as an intelligent and intuitive way of creating structures with material economy, structural efficiency and visual elegance.

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