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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.
161

Efeitos da expansão rápida da maxila cirurgicamente assistida na síndrome da apneia obstrutiva do sono, na sonolência diurna e na morfologia da via aérea / Effects of surgically assisted rapid maxillary expansion on obstructive sleep apnea syndrome, on daytime sleepiness and on airway morphology

Pedro Pileggi Vinha 22 May 2015 (has links)
A apneia obstrutiva do sono é uma síndrome que produz múltiplas comorbidades, aumentando significativamente a taxa de mortalidade dos seus portadores. A atresia maxilar vem sendo descrita como um dos fatores etiológicos da SAOS, entretanto não existem estudos que demonstrem a eficácia no tratamento em adultos com consequente redução dos eventos obstrutivos durante o sono. Este trabalho tem como objetivo principal a verificação da expansão rápida da maxila cirurgicamente assistida (ERMCA), nos eventos obstrutivos do sono e demais parâmetros polissonográficos, na sonolência diurna e no comportamento morfométrico da via aérea. A amostra foi realizada em indivíduos adultos com apneia obstrutiva do sono (SAOS), atresia maxilar e mordida cruzada. O método adotado foi um ensaio clínico prospectivo com 16 participantes (7 mulheres / 9 homens) com idade de 40,23 ± 10,23, todos portadores de SAOS comprovada por polissonografia (PSG) de noite toda (IDR superior a 5), atresia maxilar e mordida cruzada posterior. Previamente todos participantes foram submetidos a uma tomografia computadorizada (TC) da via aérea superior e foi aplicado o teste da Escala de Sonolência de Epworth (ESE). Todos os pacientes foram então submetidos à ERMCA, e posteriormente, todos os exames foram refeitos para comparação. Foi constatada uma redução no IDR de 35,46 ± 38,54 para 16,07 ± 19,73, uma redução média de 54,68% (p=0,0013) e no IAH em 56,24% (33,23 ± 39,54 para 14,54 ± 19,48: p=0,001), uma redução dos índices de microdespertares e dessaturação, além da melhora de diversos parâmetros polissonográficos. O ESE apresentou uma melhora de 12,50 ± 5,32 para 7,25 ± 3,53 (p<0,001). A via aérea total ampliou em média 23,99% (p=0,016), mas de uma maneira mais expressiva na sua metade inferior (28,63% p=0,008). Em relação aos resultados obtidos por meio da ERMCA observou-se uma melhora da SAOS, redução dos índices relacionados aos distúrbios respiratórios durante o sono, de microdespertar e de dessaturação, ampliação da via aérea, principalmente na metade inferior, além de melhorar a sonolência diurna, devolvendo- a para a normalidade. / Obstructive sleep apnea syndrome (OSAS) is a condition that produces multiple comorbidities, significantly increasing the mortality rate of affected individuals. Maxillary atresia is being described as one of the etiological factors of OSAS, although there are no studies demonstrating the efficacy of treatment in adults with a consequent reduction of obstructive events during sleep. The main objective of the present study was to determine the effects of surgically assisted rapid maxillary expansion (SARME) on obstructive sleep events and all other polysomnography (PSG) parameters, on daytime sleepiness and on the morphometric behavior of the airways. The study was conducted on adult individuals with OSAS, maxillary atresia and crossbite. The method involved a prospective clinical assay with 16 participants (7 women/9 men) aged 40.23 ± 10.23 years, with OSAS confirmed by all-night PSG (respiratory disorder index (RDI) higher than 5), maxillary atresia and posterior crossbite. All participants were first submitted to computed tomography of the upper airways and to the Epworth Sleepines Scale (ESS) test. All patients were then submitted to SARME and all exams were later repeated for comparison. RDI was reduced from 35.46 ± 38.54 to 16.07 ± 19.73, (a mean reduction of 54.68%, p=0.0013), the apnea-hypopnea index (AHI) was reduced from 33.23 ± 39.54 to14.54 ± 19.48 (a mean reduction of 56.24%, p=0.001), and micro-awakenings and desaturation were also reduced. The ESS score improved from 12.50 ± 5.32 to 7.25 ± 3.53 (p<0.001). Mean total airway area was increased by 23.99% (p=0.016), although in a more expressive manner in the lower half (28.63%, p=0.008). The results obtained by SARME revealed an improvement of OSAS, a reduction of the indices related to respiratory disorders during sleep, of micro-awakennings and of desaturation, as well as airway expansion, especially in the lower half, and improvement of daytime sleepiness with a return to normality.
162

Influência do tratamento da respiração oral na sintomatologia de crianças com Transtorno do Déficit de Atenção/Hiperatividade / Influence of the treatment of mouth breathing on the symptoms of attention deficit hyperactivity disorder

Carolina Marins Ferreira da Costa 13 April 2007 (has links)
INTRODUÇÃO: A literatura confirma a relação existente entre os Distúrbios Respiratórios do Sono (DRS) e os sintomas do Transtorno do Déficit de Atenção/Hiperatividade (TDAH). Há estudos que mostram o efeito dos tratamentos para DRS no comportamento, observando-se, após adenotonsilectomia, melhora nos índices dos testes de comportamento, assim como no desempenho escolar das crianças com TDAH. Considerando-se a relação existente entre a Respiração Oral (RO) e os DRS e entre estes e o TDAH, pretende-se avaliar se ocorrem interferências sintomáticas entre a RO e o TDAH, quando se obtém a reversão da RO em respiração nasal fisiológica, através da utilização do tratamento ortopédico funcional (utilização de placas ortopédicas, orientação para o fechamento labial, ginástica respiratória) e terapia fonoaudiológica. MÉTODOS: Neste estudo longitudinal, realizado entre janeiro de 2004 e janeiro de 2007, acompanhando pacientes com TDAH e RO, de 7 a 13 anos de idade, por 18 meses, no ambulatório de TDAH do Hospital das Clínicas/ FMUSP, comparamos os escores de testes comportamentais para TDAH (Conners e SNAP IV) em dois grupos de pacientes que estavam sendo tratados com metilfenidato, um dos quais recebeu tratamento ortopédico funcional e fonoaudiológico para a RO. RESULTADOS: 1) Não houve diferenças entre o grupo tratado e não tratado para a RO com respeito à idade; 2) Os escores dos questionários no grupo tratado para RO foram significantemente diminuindo (indicando melhora) em todas as variáveis (exceto Conners Pais -conduta anti-social), ao longo do tempo; 3) Os escores dos questionários no grupo tratado para RO foram significantemente menores (indicando melhora) do que os escores do grupo não tratado, para todas as variáveis estudadas, quando se comparam os dois grupos; 4) Esta melhora dos sintomas ocorreu após 12 meses de tratamento para RO e persistiu aos 18 meses; 5) dois dos oito pacientes do grupo tratado puderam interromper o metilfenidato, sendo que todos os pacientes do grupo não tratado ainda utilizam o medicamento. CONCLUSÕES: O Tratamento Ortopédico Funcional para RO, em conjunto com a terapia fonoaudiológica, foi efetivo para a melhora dos sintomas de TDAH em pacientes em tratamento com metilfenidato; a RO e os DRS devem ser investigados e tratados em pacientes com diagnóstico ou suspeita de TDAH, pois podem contribuir para a piora dos sintomas. / INTRODUCTION: A number of studies demonstrate the relationship between Sleep Respiratory Disorders (SRD) and symptoms of the Attention Deficit Hyperactivity Disorder (ADHD). Some of them assess the effect of the treatments for SRD on the behavior; for example, an improvement of the scores in the behavior tests, as well as in the school performance of children with TDAH is observed after adenotonsillectomy Considering the relation between mouth breathing (MB) and SRD and between these and the ADHD, we aimed to evaluate symptomatic interferences between MB and ADHD, through the reversion of MB in physiological nasal breath, by means of functional orthopedics treatment (use of orthopedics plates, orientation for labial closing, respiratory gymnastics) and speech therapy. METHODS: In this longitudinal study, performed between January of 2004 and January of 2007, 16 patients with ADHD and MB, aged 7 to 13 years, and who were being treated with methylphenidate, were followed-up for 18 months, in the outpatient clinic for ADHD at the Hospital das Clínicas da FMUSP. We compared the scores in ADHD tests (Conners and SNAP IV) of two groups of eight patients, one of which received functional orthopedics treatment and speech therapy for MB and the other did not. RESULTS: 1) The two groups were statistically equivalent by age; 2) The scores of the questionnaires in the group of patients treated for MB were significantly lowering (indicating improvement) regarding all the variables (except Conners Parents - antisocial behavior), along the follow-up period; 3) The scores of the questionnaires in the treated group were significantly lower (indicating improvement) of the scores in no treated group, for all the studied variables, when the two groups are compared; 4) This improvement of the symptoms occurred 12 months after the beginning of the treatment for MB and persisted at 18 months; 5) two of the eight patients from the treated group were indicated for interrupting the methylphenidate; however, all patients of the group not treated were still utilizing the medication. CONCLUSIONS: Functional the Orthopedics Treatment for MB, associated with speech therapy, was effective for the improvement of the symptoms of ADHD in patients who were being treated with methylphenidate; MB and SRD must be investigated and treated in patients with diagnosis or suspicion of ADHD, as they can contribute for the worsening of the symptoms.
163

Evolução das dimensões da faringe, crescimento craniofacial e sintomas respiratórios em crianças que roncam por aumento das tonsilas faríngea e palatinas tratadas com aparelho ortodôntico Biojusta X / Evolution of the pharyngeal dimensions, facial growth, and respiratory symptoms in snoringchildren with tonsil and adenoid hypertrophy after treatment with the Bioajusta X orthodontic and orthopedic oral appliance

Walter Ribeiro Nunes Junior 27 February 2013 (has links)
Introdução- Obstrução das vias aeríferas superiores associadas a mudanças nos padrões de sono, estão diretamente relacionados a problemas de crescimento e aprendizagem, o que interfere com a qualidade de vida das crianças com este quadro. Métodos de expansão maxilar já mostraram efeito favorável sobre a função respiratória. Aparelhos removíveis intra-orais têm sido usados no tratamento do ronco e apneia do sono, buscando reequilibrar a postura da mandíbula e da língua para melhorar a função respiratória. O objetivo deste trabalho é avaliar as dimensões da faringe, o crescimento craniofacial e os sintomas respiratórios obstrutivos em crianças com ronco e aumento das tonsilas faríngeas e palatinas em tratamento com um aparelho ortodôntico e ortopédico bucal. Métodos- Quarenta crianças de 6 a 9 anos de idade com tonsilas faríngeas e palatinas graus 3 e 4 e apresentando maxila atrésica e sobressaliência anterior foram divididos em dois grupos aleatórios: 24 pacientes tratados com o aparelho oral e 16 controles não tratados. As dimensões da faringe foram medidas por faringometria acústica. Cefalometria avaliou o crescimento facial, incluindo os valores relacionados com a apnéia do sono. Os pais preencheram questionários sobre os sintomas respiratórios da criança. Os pacientes foram reavaliados após 6 meses, em ambos os grupos. Resultados: A faringometria acústica confirmou um aumento volumétrico de 3,1 cm3 (d.p. ± 2,5) na faringe, no grupo de estudo e uma redução volumétrica de -1,2 cm3 (d.p. ± 1,3) no não tratado (p <0,001). A área mínima de colapsibilidade no grupo de estudo apresentou incremento de 1,1 cm2 (dp ± 0,2) para 1,3 cm2 (d.p. ± 0,2) e uma redução no grupo controle de 1,5 cm2 (dp ± 0,3) para 1,3 cm2 (d.p. ± 0,3) estatisticamente significante (p <0,001). A cefalometria comprovou crescimento craniofacial mais favorável no grupo de estudo, em comparação aos controles, incluindo os valores relacionados a apnéia do sono, como ANB, MMPA e H-ML (p <0,001) . O questionário de sintomas confirmou uma melhoria no padrão de respiração e sono no grupo tratado. Conclusão- As crianças que foram submetidos a esse protocolo de tratamento apresentaram aumento de dimensões da faringe, direção de crescimento mais favorável, e uma melhora na respiração e qualidade do sono / Introduction- Airway obstruction due to associated changes in sleep patterns are directly related to problems of growth and learning, which interfer with the quality of life for these children. Maxillary expansion methods have shown favorable effect on respiratory function. Intra-oral removable appliances have been used in the treatment of snoring and sleep apnea, seeking to rebalance the posture of the jaw and tongue to improve breathing function. The purpose of this thesis is evaluate the facial growth, pharyngeal dimensions and respiratory symptoms in snoring children with enlarged tonsils and adenoids under treatment with an orthodontic and orthopedic oral appliance. Methods- Forty snoring children ages 6 to 9 years old with tonsil and adenoid enlargement grades 3 and 4 and presenting constricted maxilla were divided into two randomized groups: 24 patients treated with the oral appliance and 16 untreated controls. Pharyngeal size was measured by acoustic pharyngometry. Cephalometry evaluated the facial growth including values related to sleep apnea. Pharyngeal size was measured by acoustic pharyngometry. Parents filled out questionnaires about their child\'s respiratory symptoms. Patients were re-evaluated after 6 months, in both groups Results- Acoustic pharyngometry confirmed a volumetric gain of 3.1 cm3 (s.d. ±2.5) in the pharynx at the study group and a volumetric reduction of -1.2 cm3 (s.d. ±1.3) at the untreated (p<0.001). The minimum area on collapsibility at the study group showed an increment from1.1 cm2 (s.d.±0.2) to 1.3 cm2 (s.d.±0.2) and a reduction on the control group from 1.5 cm2 (s.d.±0.3) to 1.3 cm2 (s.d.±0.3) statistically significant (p<0.001). Cephalometry showed a more favorable facial growth on the study group compared to controls, including values related to sleep apnea prediction such as ANB, MMPA and H-ML (p<0.001). The symptoms questionnaire confirmed an improvement on the breathing pattern at the group treated. Conclusions- Children who underwent this treatment protocol presented more favorable growth direction, enlargement of pharyngeal dimensions, and an improvement in breathing and sleep
164

Estudo da variação das medidas ortodônticas e da função respiratória nasal por rinometria acústica e rinomanometria em pacientes submetidos à expansão palatina cirurgicamente assistida / Study of the orthodontic measures variation and the nasal respiratory function through acoustic rhinometry and rhinomanometry in patients who have undergone surgically assisted rapid maxillary expansion

Camila Eduarda Zambon 27 April 2010 (has links)
Introdução: A atresia transversa da maxila é a discrepância volumétrica existente entre a maxila e a mandíbula no plano transversal que, além de alterações dento-esqueléticas, gera mudanças craniofaciais importantes, como o estreitamento das cavidades nasais, a diminuição da permeabilidade nasal e a respiração bucal. A expansão palatina cirurgicamente assistida (EPCA) é a técnica cirúrgica indicada para a correção da atresia maxilar em pacientes adultos, com o crescimento ósseo finalizado. A rinometria acústica é uma técnica objetiva de estudo da respiração nasal, com a qual se avalia a geometria e o volume nasal. Já a rinomanometria trata-se de um método aerodinâmico que quantifica a pressão transnasal e a resistência ao fluxo aéreo. Objetivos: O objetivo deste estudo foi avaliar subjetiva e objetivamente a função respiratória nasal, em pacientes com atresia maxilar, submetidos à EPCA e determinar o tipo de correlação existente entre as medidas ortodônticas e as alterações de área, volume, resistência, e fluxo aéreo nasal. Casuística e Métodos: Para a realização do estudo foram avaliados 27 pacientes adultos, por meio da rinometria acústica, rinomanometria, medidas ortodônticas (perímetro e comprimento do arco maxilar, distância transversa entre caninos, prés-molares e molares superiores) em modelos de estudos e escala visual analógica da função respiratória apenas nasal, no pré-operatório, após a ativação do expansor maxilar do tipo Hyrax, instalado previamente à cirurgia, e após quatro meses da EPCA, realizada sob anestesia geral. Os exames otorrinolaringológicos foram realizados em sala ambientalizada, com e sem o uso de vasoconstritor nasal, em ambas as cavidades nasais. Resultados: Os resultados demonstraram que 59,3% da casuística era do gênero feminino, com idade média de 25,33 anos. Todas as medidas ortodônticas obtiveram um aumento estatisticamente significante (p<0,001), que mantiveram-se ao longo da tempo (p<0,001). Todas as medidas avaliadas apresentaram melhores resultados com o uso de vasoconstritor nasal. A área da cavidade nasal como um todo aumentou após a cirurgia (p<0,036). O volume médio é 2,75 maior com o uso de vasoconstritor (p < 0,001), porém não houve alterações estatisticamente significantes entre os momentos avaliados. Os fluxos expiratórios e inspiratórios aumentaram ao longo do tempo (p<0,001, para ambos). A pressão expiratória diminui no decorrer dos momentos avaliados (p<0,004). A análise subjetiva da sensação respiratória apenas pelo nariz aumentou significantemente de um momento para o outro (p<0,05). Houve correlação estatística entre perímetro do arco aumentado e resistência aérea diminuída (p=0,004) e entre o aumento de uma medida transversa com o aumento do fluxo inspiratório e expiratório, sem o uso de vasoconstritor (p=0,023 e p=0,004 respectivamente). Apenas o fluxo respiratório apresentou comportamento diferente entre os lados. Conclusões: Assim, conclui-se que o procedimento cirúrgico de EPCA promove alterações importantes nas cavidades oral e nasais que, associadas, geram melhor qualidade respiratória ao paciente e demonstram a relevância clínica otorrinolaringológica de tal procedimento cirúrgico bucomaxilofacial / Introduction: Transverse atresia of maxilla is a volumetric discrepancy existing between the maxilla and the mandible on the transversal plan that, besides dentoskeletal alterations, generates important craniofacial changes, such as nasal cavities constriction, diminution of nasal permeability and buccal breathing. The surgically assisted rapid maxillary expansion (SARME) is the surgical technique indicated for correcting maxillary atresia in adult patients, whose bone development was concluded. Acoustic rhinometry is a technique of nasal breathing, with which the nasal geometry and volume are assessed. As for rhinomanometry, it is an aerodynamic method that quantifies the transnasal pressure and resistance to aerial flow. Objectives: The purpose of this paper was evaluating subjectively and objectively the nasal respiratory function in patients with maxillary atresia, who have undergone SARME and determining the type of correlation existing between the orthodontic measures and the alterations of area, volume, resistance, and nasal aerial flow. Casuistic and Methods: For the paper accomplishment were assessed 27 adult patients, through acoustic rhinometry, rhinomanometry, orthodontic measures (perimeter and length of maxillary arch, transverse distance among canines, premolars and superior molars) in models of studies and analogical visual scale of only nasal respiratory function, on pre-surgical, after the activation of Hyrax-type maxillary expander, installed previously to the surgery, and after four months of SARME, accomplished under general anesthesia. The otorhinolaryngological tests were accomplished in an environmentally adapted room, with and without the use of nasal vasoconstrictor, in both nasal cavities. Results: The results have demonstrated that 59.3% of the casuistic was of female gender, with an average age of 25.33 years. All the orthodontic measures have obtained a statistically significant growth (p<0.001), which have maintained along the time (p<0.001). All the assessed measures have presented better results with the use of nasal vasoconstrictor. The nasal cavity area as a whole augmented after the surgery (p<0.036). The average volume is 2.75 larger with the vasoconstrictor use (p < 0.001), however, there was any statistically significant alterations between the moments assessed. The expiratory and inspiratory flows have grown along the time (p<0.001, for both). The expiratory pressure is reduced in the course of the moments assessed (p<0.004). The subjective analysis of respiratory sensation only through nose has increased significantly from one moment to the other (p<0.05). There was a statistic correlation between perimeter of augmented arch and aerial resistance diminished (p=0.004) and between the increase of a transverse measure with the growth of inspiratory and expiratory flow, with and without the use of vasoconstrictor (p=0.023 and p=0.004 respectively). Only the respiratory flow presented a different behavior between the sides. Conclusions: Thus, it is concluded that the SARME promotes important alterations on oral and nasal cavities that, associated, generate a better respiratory quality to the patient and demonstrate a clinical otorhinolaryngological relevance of such bucomaxillofacial surgical procedure
165

Vývoj a dynamika palatální a faryngeální dentice u jesetera malého / Development and dynamics of the palatal and pharyngeal dentition in sterlet

Novotná, Štěpánka January 2021 (has links)
Dentition is a key vertebrate innovation showing not only great morphological diversity, but also different maintenance or replacement of functional teeth. Most extant vertebrates replace their dentition through addition of new teeth from deeply invaginated epithelium, i.e. the successional dental lamina, due to presence of dental stem cells. However, in some early branching lineages of ray-finned fishes (Actinopterygii), new tooth germs arise from the adjacent superficial epithelium without the presence of the successional dental lamina. Whether the two types of dental development in vertebrates are equivalent and whether comparable dental stem cells play role in tooth replacement is currently not satisfactorily evaluated. This Master thesis aims at describing the development of palatal and pharyngeal dentition of a member of an early branching lineage of ray-finned fishes, the sterlet sturgeon (Acipenser ruthenus). The sterlet dentition is fairly dynamic. The teeth are replaced without the successional dental lamina, however, this replacement shows characteristics similar to those described in vertebrates with the successional dental lamina. A marker of dental stem/progenitor cells, Sox2, is localized in the outer dental epithelium of the predecessor tooth in the vicinity of the adjacent taste...
166

Research related to Pathoses of the oral mucosa in South Africa (1964 - 1995)

van Wyk, CW January 1995 (has links)
Doctor Scientiae (Odontology) - DSc(Odont) / Investigations of pathoses of the oral cavity encompass a relatively wide spectrum of diseases, abnormalities, tumours and tumour-like conditions affecting and occurring in the dental hard tissues and supportive structures, the bony skeleton of the face and the soft tissues of the. mouth. It involves a study of the normal - oral biology - and the abnormal - oral pathology. Oral pathology is a relatively new specialized field of dental science and practice. In South Africa, prior to the nineteen-fifties, research in oral pathology was primarily directed towards dental disease. Two people - Julius Staz of the University of the Witwatersrand and Tony Ockerse of the University of Pretoria - were the doyens in this field and made major contributions to dental science. Staz reported on the status of dental caries and tumorous malformations of teeth and Ockerse on the prevalence and severity of fluorosis in South Africa. During the fifties a second generation of dental surgeons, who were interested in soft tissue, bone and tumour pathology, emerged. They ,were Bertie Cohen, George Baikie, Mervyn Shear and John Lemmer who, at that time, were all from the University of the Witwatersrand. Bertie Cohen later joined the Royal College of Surgeons of England. Mervyn Shear led the field with his research on cysts of the oral cavity. The practice of oral pathology, moulded on anatomical pathology, was established in the early sixties and Mervyn Shear and the author, from the University of Pretoria, became known as oral pathologists. Research at that early stage comprised clinical and histological observations of oral lesions, diseases, tumours and tumour-like conditions. Observation techniques became more sophisticated during the sixties and seventies with the advent of histochemistry and electronmicroscopy. The next major development which blossomed in the seventies and early eighties was the application of epidemiological methods in the study of disease. Epidemiological principles enabled the correct recording of profiles of oral pathoses in the community. Much was learnt about the prevalence and distribution of oral conditions. The application and use of experimental models, especially laboratory animals, became popular in the eighties. Amongst others, a germfree animal unit was established in the Faculty of Dentistry of the University of Stellenbosch enabling workers to study the microbiological aetiology of dental and oral disease. Morphological observations of tumours and mucosal lesions were further enhanced during this period with the development of immunocytochemistry Experimental cell studies by means of cell culture techniques, commenced late in the eighties and was established in the early nineties. These models fostered molecular biology techniques which have become useful tools for the investigation of the aetiology of disease at a cellular and molecular level. At present molecular techniques are also popular in other spheres of oral pathology such as microbiological, immunological and oncological research. The author's first contact with oral pathology as a subject, forming an important and interesting part of dentistry, was the prescribed textbook "Oral and Dental Diseases", 2nd ed., 1951., by HH Stone of the University of Liverpool in the United Kingdom. Subsequently an enduring interest in the subject and research was cultivated by three teachers and colleagues, Ivor Kramer, Robert Bradlow and Mervyn Shear. Ivor Kramer, Professor of Oral Pathology in the Eastman Dental Institute of the University of London was a superb postgraduate teacher of oral pathology, and revelled in research. The Dean of the Institute, Professor Sir Robert Bradlow was a clinician and splendid diagnostician. He correlated the clinical and histopathological features of oral diseases. These two teachers set the course in oral pathology for the author during his postgraduate studies. In the sixties, after a spell at the University of Pretoria, the author joined Professor Mervyn Shear at the University of Witwatersrand. It was here that the author could further his skills of presenting lectures and research papers in an orderely manner and strengthen his love of research. The research carried out by the author reflects to a large extent the development of research in oral pathology in South Africa since 1960.. It includes studies of diseases and lesions of the oral mucosa, the dental hard tissues, tumours of the oral cavity and jaws and forensic odonto-stomatology. To date 139 articles have been published and accepted in scientific journals of which I was the first or co-author. The research presented here, however, comprises only those studies related to pathoses of the oral mucosa as it occurs in South Africa. Fifty-four papers and two abstracts are submitted. The papers are grouped into two divisions which include studies on (I) normal human oral and ectocervical mucosa and (II), those related to pathoses of the oral mucosa. The latter is subdivided into sections on: the profile of lesions of the oral mucosa in the community; cytological, clinical and morphological features of lesions of the oral mucosa; and studies on the aetiology of lesions of the oral mucosa. Each division and section is preceded by a declaration as to the contribution of the author or co-authors and a précis of the aims, objects and research findings. In the introduction of the précis statements are made explaining the aims of the study. These statements are not referenced because they appear in the respective articles.
167

Examination of the (si) and (ʃi) confusion by Japanese ESL learners

Nogita, Akitsugu 30 August 2010 (has links)
It is a general belief in Japan that the English /s/ and /ʃ/ before high front vowels (as in "see" and "she") are problematic for Japanese ESL (English-as-a-second-language) learners. Some research has also reported the /s/ and /ʃ/ confusion by Japanese ESL learners. Their pronunciation errors are often explained based on phonetics, but there are reasons to believe that the learners’ knowledge of the phonemes of the target words is at fault. This study examines 1) whether monolingual Japanese speakers distinguish the [si] and [ʃi] syllables in both perception and production in the Japanese contexts and 2) what would be the sources of Japanese speakers’ challenges in mastering the distinction between [si] and [ʃi] in their English production if Japanese speakers can produce and perceive the difference between these syllables. This study conducted two experiments. In the first experiment, 93 monolingual Japanese speakers between the ages of 17 and 89 in and around Tôkyô read aloud the written stimuli that had [si] and [ʃi] in the Japanese contexts, repeated the sound stimuli that had [si] and [ʃi] in the Japanese contexts, and listened to the [si:] and [ʃi:] syllables in isolation recorded by a native speaker of Canadian English. The results showed that the participants all distinguished [si] and [ʃi] in both perception and production regardless of their ages. Based on these results, I hypothesized that the [s] and [ʃ] confusion by Japanese ESL learners is caused by misunderstanding, rather than an inability to articulate these sounds. In the second experiment, 27 Japanese ESL students were recorded reading an English passage. The passage contains /s/ (7 times) and /ʃ/ (11 times) before high front vowels. After the reading, the participants were taught the basic English phonological system and the symbol-sound correspondence rules such as “s”-/s/ and “sh”-/ʃ/. The lesson lasted 40 minutes during which the participants were also interviewed to find out their awareness of the symbol-sound correspondence. No articulation explanations were given during the lesson. After the lesson, the participants read the same passage. The results showed that /s/ and /ʃ/ were mispronounced 39 and 67 times respectively in total by the 27 participants before the lesson, but only 7 and 19 times after the lesson. These changes are statistically significant. Moreover, the interview during the lesson revealed that the participants lacked phonological awareness in English as well as the knowledge of the symbol-sound correspondence rules. This study concluded that many of the mispronunciations by Japanese ESL learners, including /s/ and /ʃ/, can be solved by teaching the English phonics rules and some basic phonological rules without teaching the articulation of these sounds.

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