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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.
41

Vývoj morfologie patra a tvaru zubního oblouku u pacienta s rozštěpem / Development of the palate morphology and dental arch form in cleft patients

Urbanová, Wanda January 2013 (has links)
Development of the palate morphology and shape of the dental arch in patients with cleft Objective: The aim of this study was to compare the differences in development of the palate morphology and in the relationship and shape of the dental arches in two groups of individuals with different types of orofacial cleft defects. Introduction: Orofacial clefts are the cause of the insufficient growth of the face. Range of the resulting deformation depends on the type of cleft, individual growth disposition of the patient and comprehensive interdisciplinary treatment of the cleft. Material and Methods: The sample consisted of 18 patients with unilateral cleft lip and palate and 18 patients with isolated cleft palate. Measurements were performed on study casts of patients aged 9 and 13 years in average. Following measurements were performed: the frontal and distal width of the upper and lower dental arch, the length of both halves of the upper dental arches, the frontal length and depth of the upper dental arch and the overjet. According to the sagittal relationship of the dental arches, patients were classified into one of five categories of the GOSLON yardstick score. The results were compared between groups and between both age periods using one- or two-sample Wilcoxon test and Fisher test for the GOSLON...
42

Vývoj morfologie patra a tvaru zubního oblouku u pacienta s rozštěpem / Development of the palate morphology and dental arch form in cleft patients

Urbanová, Wanda January 2013 (has links)
Development of the palate morphology and shape of the dental arch in patients with cleft Objective: The aim of this study was to compare the differences in development of the palate morphology and in the relationship and shape of the dental arches in two groups of individuals with different types of orofacial cleft defects. Introduction: Orofacial clefts are the cause of the insufficient growth of the face. Range of the resulting deformation depends on the type of cleft, individual growth disposition of the patient and comprehensive interdisciplinary treatment of the cleft. Material and Methods: The sample consisted of 18 patients with unilateral cleft lip and palate and 18 patients with isolated cleft palate. Measurements were performed on study casts of patients aged 9 and 13 years in average. Following measurements were performed: the frontal and distal width of the upper and lower dental arch, the length of both halves of the upper dental arches, the frontal length and depth of the upper dental arch and the overjet. According to the sagittal relationship of the dental arches, patients were classified into one of five categories of the GOSLON yardstick score. The results were compared between groups and between both age periods using one- or two-sample Wilcoxon test and Fisher test for the GOSLON...
43

POSTURAL ADAPTATIONS IN ARCHWIRE EXPANSION WITH SELF-LIGATING BRACKETS

Padilla, Mark Thomas January 2014 (has links)
Objectives: Orthodontic arch development expands and broadens the dentition beyond the confines of the original arch perimeter. This is often accomplished by means of self-ligating fixed appliances. When movements take the teeth outside those confines, without adoption, the muscular forces are unbalanced and may lead to dental relapse. Muscle spindles and associated reflex loops within the tongue provide feedback to arch perimeter changes that may produce postural changes to the new archform. Resting posture has long been accepted as aiding in tooth position. The objective of this study was to assess the oral and pharyngeal postural changes that result from arch development with the Damon system and report the amount of expansion accomplished. Methods: Pre- and post-treatment models and lateral cephalograms were collected on 69 previously treated orthodontic patients from four different private practices. Expansion was measured from the buccal cusp tips of the first and second premolars and first molars. A new cephalometric analysis was implemented to diagnose both variations in malocclusion and variations in posture of the head, neck, pharynx, hyoid bone and tongue. Results: Both tongue height and length increased, 2.9mm (P-value 0.001, SEM=1.06) and 3.76mm (P-value 0.00002, SEM=0.62) respectively, following posterior dental arch expansion using Damon archwires. Hyoid position was not significantly different. Conclusion: As dental arches are expanded the tongue increases in both length and height to fill the space and therefore may aid in stability during the retention phase of treatment. The lack of change in hyoid bone position, as one would expect with a rise in tongue position, might be explained by either slight changes in head position or the need to maintain the airway. / Oral Biology
44

The relationship of the upper anterior teeth to the incisive papilla in Cantonese adults

Lau, Chi-kai, George., 劉熾佳. January 1990 (has links)
published_or_final_version / Dentistry / Master / Master of Dental Surgery
45

Avaliação comparativa da Borda WALA em mandíbulas secas e modelos e da sua mensuração em radiografias oclusais e tomografias / A comparative assessment of the WALA ridge in dissected mandibles and cast models as well as its measurement in occlusal radiographies and tomographies

Moura Neto, Gastão 06 May 2010 (has links)
Introdução: a determinação da Borda WALA em modelos de gesso permitia defini-la como uma linha imaginária utilizada no planejamento, seguimento e finalização de casos clínicos. Procurou-se determinar a Borda WALA em modelos de gesso de pacientes ortodônticos, mandíbulas secas, radiografias oclusais e cortes tomográficos dos pacientes e mandíbulas respectivas. O objetivo foi detectar a viabilidade de mensurar e determinar, por um método reproduzível, a Borda WALA em radiografias oclusais e cortes tomográficos. Metodologia: foram utilizados modelos, radiografias oclusais e tomografias de feixe cônico de 12 pacientes ortodônticos, e 12 mandíbulas e suas respectivas radiografias oclusais e cortes tomográficos. As mensurações tomográficas foram realizadas, em todos os dentes, do ponto mais vestibular das raízes dentárias no nível cervical até a parte mais externa da cortical óssea vestibular. Nas mandíbulas secas e nos modelos, as medidas verticais partiam do ponto EV até a linha de grafite que determinou o ponto vestibular mais externo. Resultados: os arcos correspondentes à Borda WALA obtidos nos modelos de gesso e nas mandíbulas secas se equivaleram em sua forma, sendo um pouco menores, em sua dimensão, nos modelos. Os arcos obtidos a partir das mensurações realizadas em radiografias oclusais e cortes tomográficos se equivaleram, em sua forma, nos modelos e mandíbulas, com correlação fortemente positiva, detectada pelo Coeficiente de Correlação de Pearson. Conclusões: 1. a Borda WALA não representa uma estrutura anatômica, mas uma medida/anagrama/referência a ser mensurada e utilizada nos tratamentos ortodônticos e ortopédicos; 2. a Borda WALA não deve ser considerada uma linha imaginária, mas um arco a ser determinado por medidas que devem servir de parâmetro nas correções das alterações da oclusão e alinhamento dos dntes inferiores; 3. em seu contorno e forma, as medidas obtidas nos modelos e nas mandíbulas, assim como nas radiografias oclusais e tomografias de feixe cônico, se equivaleram estatisticamente. Nas radiografias oclusais dos pacientes, houve dificuldades técnicas para a obtenção de imagens que permitissem uma mensuração precisa na determinação da Borda WALA. Nos cortes tomográficos, as medidas realizadas para determinação da Borda WALA reproduziram, com coeficiente de correlação fortemente positivo, a dimensão e a forma obtidas em medidas nos modelos de gesso e nas mandíbulas secas. Em suma, a determinação da Borda WALA a partir de cortes tomográficos transversais no nível cervical dos dentes inferiores é viável, pois a dimensão e a forma do arco obtido se equivalem estatisticamente ao arco obtido pelas medidas realizadas em modelos de gesso e mandíbulas secas. / Introduction: The WALA ridge is an imaginary line determined in cast models and used as reference for orthodontic treatment planning, execution and finalization. In the following study, the WALA ridge was defined in cast models of orthodontic patients, dissected mandibles, occlusal radiographies and tomographic slices of patients and respective mandibles aiming to find a reproducible method for determining the WALA ridge in occlusal radiographies and tomographic slices. Methodology: The sample comprised 12 cast models, occlusal radiographies and cone beam tomographies of orthodontic patients and 12 dissected mandibles, their respective occlusal radiographies and tomographic slices. Tomographic measurements were made in all teeth from the most buccal point of dental roots on their cervical level until the most external and anterior cortical line of bone. Vertical measurements on dissected mandibles and cast models were taken from FA point until the pencil line that determined the most external edge of bone around mandibular teeth. Results: The arches corresponding to the WALA ridge obtained from cast models and dissected mandibles were equivalent in form but a little smaller in size for cast models. The arches obtained from occlusal radiographies and tomographic slices were equivalent in form to the ones obtained from models and dissected mandibles, with a high positive correlation of proportion statistically confirmed by Pearsons coefficient. Conclusion: 1. The WALA ridge is not an anatomical structure, but a measurement/anagram/reference to be measured and used during orthodontic and orthopedic treatment. 2. The WALA ridge should not be considered an imaginary line, but an arch to be determined by measurements and used as parameter when correcting the occlusion of misalignment of inferior teeth; 3. The measurements obtained from models and dissected mandibles, as well as from occlusal radiographies and cone beam tomographies were equivalent in shape and form. Obtaining the WALA ridge from occlusal radiographies in patients involve technical difficulties to acquire a good image for precise measurement. Tomographic measurements to determine the WALA ridge were reproducible, with a high positive correlation coefficient to the dimension and form obtained from cast models and dissected mandible measurements. To sum up, determining the WALA ridge from tomographic transversal slices on the cervical level of inferior teeth is viable, since the dimension and arch form are statistically equivalent to the arch form obtained from cast models and dissected mandibles.
46

Análise da oclusão dentária em crianças portadoras de fissura completa de lábio e palato / Analysis of dental occlusion in children with complete cleft lip and palate

Crepaldi, Jairo Lessa 13 June 2012 (has links)
As fissuras labiopalatinas alteram o crescimento e o desenvolvimento do complexo maxilo-mandibular, assim como todas as funções orofaciais. As cirurgias reparadoras primárias representam o maior agente modificador do crescimento maxilo-facial, de forma a restringi-lo. O sucesso do tratamento reabilitador do paciente fissurado depende da correta atuação de uma equipe multidisciplinar. Este trabalho teve como objetivo avaliar as condições oclusais em modelos de gesso de pacientes portadores de fissura labiopalatina completa, não sindrômicos, correlacionando o prognóstico ao tipo de fissura, fase de desenvolvimento da dentição, gênero e hospital de reabilitação cirúrgica. Utilizou-se 87 pares de modelos das arcadas dentárias de pacientes fissurados do Ambulatório da Disciplina de Prótese Buco Maxilo Facial da Faculdade de Odontologia da Universidade de São Paulo, que haviam sido submetidos às cirurgias reparadoras primárias em cronologia clássica (queiloplastia 3 a 6 meses e palatoplastia 18 meses), sem enxerto ósseo alveolar e/ou tratamento ortodôntico prévio. O grupo estudado foi composto de 57 pacientes com Fissura Labiopalatina unilateral, com idade média de 6 anos e 5 meses e 30 pacientes com Fissura Labiopalatina bilateral com idade média de 6 anos e 2 meses. Para a classificação dos modelos em gesso de fissurados unilaterais, foram utilizados o Índice de 5 anos e o Índice de Goslon, na dentição decídua e mista respectivamente, enquanto que para as fissuras bilaterais empregou-se o Índice de Bilateral. Os três índices referidos compreendem uma escala de 1 a 5, com grau crescente de severidade de má oclusão. Os modelos foram avaliados pelo pesquisador e mais 2 examinadores, em dois momentos distintos, quando se alcançou um alto grau de confiabilidade e reprodutibilidade (Teste de Cronbach e Análise de Correlação de Spearman). Posteriormente, para as análises complementares, utilizaram-se apenas os dados fornecidos pelo pesquisador, os quais foram agrupados em prognóstico dos resultados a longo prazo em: bom (graus 1 e 2); regular ( grau 3 ) e pobre ( graus 4 e 5 ). Aplicou-se o Teste da Razão de Verossimilhança para verificar as possíveis diferenças entre as variáveis de interesse, quando não se encontrou, para a amostra total, correlação entre prognóstico e tipo de fenda, gênero e hospitais de reabilitação. Apenas nos pacientes com fissuras unilaterais houve associação do prognóstico à fase de dentição (p=0,019) e aos hospitais de reabilitação (p=0,025). Este trabalho permitiu concluir que as fissuras unilaterais na fase de dentição decídua mostraram menor severidade de má-oclusão, e que o Hospital de referência da Faculdade de Odontologia da Universidade de São Paulo apresentou resultados mais favoráveis em relação aos demais. / The cleft lip and palate alter the growth and development of the maxillo-mandibular complex as well as all orofacial functions. Primary repair surgery represents the largest modifier agent of maxillofacial growth in order to limit it. The success of the rehabilitation treatment of the cleft patient depends on the correct performance of a multidisciplinary team. This study aimed to assess the occlusal conditions, in plaster models, of patients with complete cleft lip and palate, non syndromic, correlating to the type of cleft, stage of dental development, gender and surgical rehabilitation hospital. For this study, 87 pairs of casts from cleft patients of the Ambulatory of Oral Maxillo Facial Prosthesis of the Faculty of Dentistry of the University of São Paulo (USP), that had been undertaken to primary classical repair surgeries (cheiloplasty 3 to 6 months and palatoplasty 18 months), without prior alveolar bone graft and/or orthodontic treatment. The group studied was composed of 57 patients with unilateral cleft lip and palate, with mean age of 6 years, 5 months and 30 patients with bilateral cleft lip and palate with mean age of 6 years, 2 months. For the classification of plaster casts for unilateral cleft, the index of 5 years and the index of Goslon, in the deciduous and mixed dentition, respectively, whereas the Bilateral index was used for bilateral cleft. The three mentioned indexes comprise a scale of 1 to 5, with increasing levels of severity of malocclusion. The models were evaluated by the researcher and two other examiners in two distinct occasions, when a high degree of reliability and reproducibility was reached. Subsequently, for the additional analysis, it was used only the data provided by the researcher, which were grouped into long-term prognosis results in: good (grades 1 and 2); regular (grade 3) and poor (grades 4 and 5). The likelihood ratio test was used to verify the possible differences between the variables of interest, and the results did not show, for the total sample, any correlation between prognostic and cleft type, gender, and rehabilitation hospitals. Only patients with unilateral clefts there was an association of the prognostic to the dental stag of dental development (p=0.019) and rehabilitation hospitals (p=0.025). This study revealed that the unilateral clefts in the deciduous dentition stage showed a lesser severity for poor occlusion, and that the Referral Hospital of the Faculty of Dentistry of the University of São Paulo has the most favorable results compared to others.
47

"Avaliação oclusal e miofuncional oral em crianças com dentição decídua completa e mordida aberta anterior antes e após remoção do hábito de sucção de chupeta" / Occlusal and oral myofunctional evaluation in children with complete primary dentition and anterior open bite before and after removal of pacifier sucking habit.

Verrastro, Anna Paula 11 January 2006 (has links)
O objetivo deste estudo foi avaliar características oclusais e miofuncionais orais em crianças entre 3 e 5 anos de idade, com mordida aberta anterior e também verificar o comportamento dessas características após remoção do hábito de sucção de chupeta. Participaram 69 crianças, 34 com oclusão normal (Grupo Controle) e 35 com mordida aberta anterior (Grupo Mordida Aberta). No Grupo Mordida Aberta, a média da mordida aberta anterior foi 2,96 mm, da sobressaliência foi 4,1 mm e da distância intercanina superior foi 28,7 mm. No Grupo Controle, a média da sobressaliência foi 2,6 mm e a da distância intercanina superior foi 30,3 mm. A média da sobressaliência foi maior (p=0,001) e a média da distância intercanina superior foi menor (p<0,001) no Grupo Mordida Aberta que no Controle. O número de crianças com relação canina classe II foi maior no Grupo Mordida Aberta que no Controle (p<0,001). A análise de regressão logística univariada mostrou que maior sobressaliência, menor distância intercanina superior e relação canina classe II coexistiram com a mordida aberta anterior. No Grupo Mordida Aberta, o número de crianças com postura de lábios entreabertos em repouso (60,0%), alteração no tônus labial (68,6%), postura inadequada de língua em repouso (65,7%), alteração no tônus de bochechas (42,9%), interposição lingual anterior durante a deglutição (91,4%) e interposição lingual anterior durante a fala (85,7%) foi maior (p<0,05) que no Grupo Controle (respectivamente 35,3%, 35,3%, 23,6%, 17,7%, 32,4% e 38,2%). A análise de regressão logística múltipla identificou a interposição lingual anterior durante a deglutição (odds ratio 18,97) e durante a fala (odds ratio 9,24) bem como a postura de lábios entreabertos em repouso (odds ratio 6,23) como as principais características miofuncionais orais nas crianças com mordida aberta anterior. Das 35 crianças do Grupo Mordida Aberta, 27 apresentavam hábito de sucção de chupeta ao início do estudo e, após orientação, 15 abandonaram o hábito e 12 diminuíram a freqüência do hábito. Observou-se que a taxa de sucesso na remoção do hábito foi 55,6%, sem diferença entre gêneros e idades. A remoção do hábito favoreceu, após 3 meses de acompanhamento, redução média da mordida aberta anterior de 1,97 mm, sendo maior (p<0,001) que nas crianças que diminuíram o hábito (0,33 mm). A média da redução da sobressaliência nas crianças que abandonaram o hábito foi 0,6 mm e a média do aumento da distância intercanina superior foi 0,67 mm, mas não foram estatisticamente diferentes das crianças que diminuíram o hábito (respectivamente 0,0 mm e 0,50 mm) nem do Controle (respectivamente 0,2 mm e 0,42 mm). A remoção do hábito de sucção de chupeta promoveu melhora na postura de lábios em repouso (p=0,0313), favoreceu a respiração nasal (p=0,0078) e reduziu a ocorrência de interposição lingual anterior durante a deglutição (p=0,0078), após 3 meses de acompanhamento. A análise de regressão logística univariada identificou a postura de língua inadequada em repouso, como a principal característica miofuncional oral capaz de impedir a correção espontânea da mordida aberta anterior nas crianças avaliadas durante esse período (odds ratio 17,50) / The aim of this study was to evaluate occlusal and oral myofunctional characteristics in children between 3 and 5 years old, with anterior open bite and also to verify the behavior of these characteristics, 3 months after removal of pacifier sucking habit. Sixty nine children participated, 34 presented normal occlusion (Control Group) and 35 presented anterior open bite (Open Bite Group). In the Open Bite Group, the mean anterior open bite was 2.96 mm, the mean overject was 4.1 mm and the mean upper intercanine distance was 28.7 mm. In the Control Group, the mean overject was 2.6 mm and the upper intercanine distance was 30.3 mm. The mean overject was larger (p=0.001) and the mean upper intercanine distance was smaller (p<0.001) in the Open Bite Group than in the Control Group. The number of children with canine class II relationship was larger in the Open Bite than in the Control Group (p<0.001). Simple logistic regression analysis showed that larger overject, smaller upper intercanine distance and class II canine relationship coexisted with anterior open bite. In the Open Bite Group, the number of children with incompetent lips at rest (60.0%), inadequate labial tonus (68.6%), inadequate posture of tongue at rest (65.7%), inadequate cheeks tonus (42.9%), tongue thrust during swallow (91.4%) and tongue thrust during speech (85.7%) was larger (p<0.05) that in the Control Group (respectively 35.3%, 35.3%, 23.6%, 17.7%, 32.4% and 38.2%). Multiple logistic regression analysis identified tongue thrust during swallow (odds ratio 18.97) and during speech (odds ratio 9.24) as well as incompetent lips at rest (odds ratio 6.23) as the main oral myofunctional characteristics in children with anterior open bite. Of the 35 children in the Open Bite Group, 27 presented pacifier sucking habit at the beginning of the study and after instruction, 15 abandoned the habit and 12 reduced the frequency of the habit. It was observed that the success rate for habit removal was 55.6%, without difference related to sex and age. The habit removal favored, after 3 months of attendance, 1.97 mm mean reduction of anterior open bite, being larger (p<0.001) compared with those children that reduced the habit (0.33 mm). The mean reduction of the overject in children that abandoned the habit was 0.6 mm and the mean increase of the upper intercanine distance was 0.67 mm, but were not statistically different from the children that reduced the habit (respectively 0.0 mm and 0.50 mm) nor from the Control (respectively 0.2 mm and 0.42 mm). The removal of the pacifier sucking habit promoted improvement in the posture of lips at rest (p=0.0313), favored the nasal respiration (p=0.0078) and reduced the occurrence of tongue thrust during swallow (p=0.0078) after 3 months of attendance. Simple logistic regression analysis identified the inadequate posture of the tongue at rest, as the main oral myofunctional characteristic capable to prevent the spontaneous correction of the anterior bite in the appraised children during that period (odds ratio 17.50)
48

Avaliação comparativa da Borda WALA em mandíbulas secas e modelos e da sua mensuração em radiografias oclusais e tomografias / A comparative assessment of the WALA ridge in dissected mandibles and cast models as well as its measurement in occlusal radiographies and tomographies

Gastão Moura Neto 06 May 2010 (has links)
Introdução: a determinação da Borda WALA em modelos de gesso permitia defini-la como uma linha imaginária utilizada no planejamento, seguimento e finalização de casos clínicos. Procurou-se determinar a Borda WALA em modelos de gesso de pacientes ortodônticos, mandíbulas secas, radiografias oclusais e cortes tomográficos dos pacientes e mandíbulas respectivas. O objetivo foi detectar a viabilidade de mensurar e determinar, por um método reproduzível, a Borda WALA em radiografias oclusais e cortes tomográficos. Metodologia: foram utilizados modelos, radiografias oclusais e tomografias de feixe cônico de 12 pacientes ortodônticos, e 12 mandíbulas e suas respectivas radiografias oclusais e cortes tomográficos. As mensurações tomográficas foram realizadas, em todos os dentes, do ponto mais vestibular das raízes dentárias no nível cervical até a parte mais externa da cortical óssea vestibular. Nas mandíbulas secas e nos modelos, as medidas verticais partiam do ponto EV até a linha de grafite que determinou o ponto vestibular mais externo. Resultados: os arcos correspondentes à Borda WALA obtidos nos modelos de gesso e nas mandíbulas secas se equivaleram em sua forma, sendo um pouco menores, em sua dimensão, nos modelos. Os arcos obtidos a partir das mensurações realizadas em radiografias oclusais e cortes tomográficos se equivaleram, em sua forma, nos modelos e mandíbulas, com correlação fortemente positiva, detectada pelo Coeficiente de Correlação de Pearson. Conclusões: 1. a Borda WALA não representa uma estrutura anatômica, mas uma medida/anagrama/referência a ser mensurada e utilizada nos tratamentos ortodônticos e ortopédicos; 2. a Borda WALA não deve ser considerada uma linha imaginária, mas um arco a ser determinado por medidas que devem servir de parâmetro nas correções das alterações da oclusão e alinhamento dos dntes inferiores; 3. em seu contorno e forma, as medidas obtidas nos modelos e nas mandíbulas, assim como nas radiografias oclusais e tomografias de feixe cônico, se equivaleram estatisticamente. Nas radiografias oclusais dos pacientes, houve dificuldades técnicas para a obtenção de imagens que permitissem uma mensuração precisa na determinação da Borda WALA. Nos cortes tomográficos, as medidas realizadas para determinação da Borda WALA reproduziram, com coeficiente de correlação fortemente positivo, a dimensão e a forma obtidas em medidas nos modelos de gesso e nas mandíbulas secas. Em suma, a determinação da Borda WALA a partir de cortes tomográficos transversais no nível cervical dos dentes inferiores é viável, pois a dimensão e a forma do arco obtido se equivalem estatisticamente ao arco obtido pelas medidas realizadas em modelos de gesso e mandíbulas secas. / Introduction: The WALA ridge is an imaginary line determined in cast models and used as reference for orthodontic treatment planning, execution and finalization. In the following study, the WALA ridge was defined in cast models of orthodontic patients, dissected mandibles, occlusal radiographies and tomographic slices of patients and respective mandibles aiming to find a reproducible method for determining the WALA ridge in occlusal radiographies and tomographic slices. Methodology: The sample comprised 12 cast models, occlusal radiographies and cone beam tomographies of orthodontic patients and 12 dissected mandibles, their respective occlusal radiographies and tomographic slices. Tomographic measurements were made in all teeth from the most buccal point of dental roots on their cervical level until the most external and anterior cortical line of bone. Vertical measurements on dissected mandibles and cast models were taken from FA point until the pencil line that determined the most external edge of bone around mandibular teeth. Results: The arches corresponding to the WALA ridge obtained from cast models and dissected mandibles were equivalent in form but a little smaller in size for cast models. The arches obtained from occlusal radiographies and tomographic slices were equivalent in form to the ones obtained from models and dissected mandibles, with a high positive correlation of proportion statistically confirmed by Pearsons coefficient. Conclusion: 1. The WALA ridge is not an anatomical structure, but a measurement/anagram/reference to be measured and used during orthodontic and orthopedic treatment. 2. The WALA ridge should not be considered an imaginary line, but an arch to be determined by measurements and used as parameter when correcting the occlusion of misalignment of inferior teeth; 3. The measurements obtained from models and dissected mandibles, as well as from occlusal radiographies and cone beam tomographies were equivalent in shape and form. Obtaining the WALA ridge from occlusal radiographies in patients involve technical difficulties to acquire a good image for precise measurement. Tomographic measurements to determine the WALA ridge were reproducible, with a high positive correlation coefficient to the dimension and form obtained from cast models and dissected mandible measurements. To sum up, determining the WALA ridge from tomographic transversal slices on the cervical level of inferior teeth is viable, since the dimension and arch form are statistically equivalent to the arch form obtained from cast models and dissected mandibles.
49

A longitudinal study of dental arch dimensions in Australian aboriginals using 2D and 3D digital imaging methods.

Thiyagarajan, Ramya January 2008 (has links)
This study investigated arch dimension changes associated with growth and tooth wear in Australian Aboriginals aged from age 8 to 15 years using 2D and 3D digital imaging systems. Serial dental casts of Australian Aboriginals from Yuendumu were used in the study. The sample comprised 25 females and 24 males for whom casts were available at ages of 8, 12 and 15 years ( a total of 294 dental study casts). The primary method of data acquisition involved obtaining digital photographs and digitizing the images using an Apple IIGS computer and customised software program. A subset of 40 dental stone models (5 individuals at ages 8, 12, 15 and 18 years) were duplicated and scanned using the Minolta Vivid 900 laser surface scanner at the DSIRO Laboratories, National University Singapore. The 3-D images were digitised using the Rapidform software package (Inus, technology, Seoul, Korea). Study variables included mesiodistal crown diameters, arch widths, arch depths and arch lengths. Mesiodistal crown dimensions in males tended to be larger than those in females. All arch dimensions were significantly larger in males than females. Upper and lower Intercanine width increased from age 8 to age 12 years but did not change thereafter. Upper and lower intermolar widths increased with age from 8 years to 15 years while arch depth decreased. No significant reduction in arch lengths was found from age 12 to 15 years. The two imaging systems were comparable in their measurement reliability, although the 2D method provided consistently larger crown diameters than the 3D method. Changes in arch dimensions with age in the Aboriginal sample were similar to those reported for other populations. However, no measurable change was detected in arch length over time, even though the Aboriginals had abrasive diets that would be expected to contribute to interproximal wear. It was concluded that the 2D and 3D imaging methods were suitable for clinical use but would require further refinement for research projects aimed at assessing minor changes in arch lengths associated with interproximal wear. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1347947 / Thesis (D.Clin.Dent.) -- University of Adelaide, School of Dentistry, 2008
50

A reevaluation of mandibular intercanine dimension and incisal position

Page, Kelly R. January 2007 (has links) (PDF)
Thesis (M.S.)--University of Alabama at Birmingham, 2007. / Title from first page of PDF file (viewed on June 26, 2009). Includes bibliographical references.

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