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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.
1

Exploratory work on the effects of rapid maxillary expansion on nasal airway dimensions

Gordon, Jillian Madeline 06 1900 (has links)
Objectives: To investigate whether any changes in nasal cavity dimensions or subjective report of nasal symptoms exist after rapid maxillary expansion using two types of expansion appliances, comparing results with an untreated control group. Methods: Subjects were randomly assigned into one of three groups: tooth-borne or bone-anchored expander or untreated control. Acoustic rhinometry was used to measure minimal cross-sectional area and volume of the nasal cavity over three timepionts for treatment subjects and two timepoints for control subjects, taken along with the NOSE Instrument survey. Results: No significant changes in nasal cavity dimension or subjective reports were found in subjects treated with tooth- or bone-anchored appliances compared to control subjects over three timepoints. In addition, non-significant correlation was observed between nasal airway dimensional change and subject symptoms. Conclusions: Rapid maxillary expansion does not result in change of i) nasal airway dimensions or ii) the sensation of nasal symptoms. / Orthodontics
2

Exploratory work on the effects of rapid maxillary expansion on nasal airway dimensions

Gordon, Jillian Madeline Unknown Date
No description available.
3

Three-Dimensional Photographic Evaluation of Immediate Soft Tissue Changes Following Rapid Maxillary Expansion

Granillo, Nathan 06 June 2011 (has links)
The skeletal and dental changes associated with rapid maxillary expansion (RME) are well documented. Effects on the soft tissues and the potential impact on facial esthetics have not been well researched. The purpose of this study was to evaluate immediate changes in facial soft tissues as a result of RME by comparing threedimensional digital photogrammetric images before and after RME treatment. The 3dMDface System was used to obtain photographic images of 21 patients (mean age = 11.8 years) before and after RME treatment for transverse maxillary deficiency. A control group of 13 patients (mean age = 12.7 years) also had two images taken at a similar time interval. Mean expansion was 6.5 mm in the RME patients. Intercanthal distance, nose width, and intercommissural width changed significantly in the RME patients from T0 to T1 (P = 0.011, P = 0.050, and P = 0.003, respectively). Intercommissural width, however, was the only measure that significantly changed as compared with the control group (P = 0.041). Changes in intercanthal distance and nose width were significantly related to the amount of expansion achieved (R2 = 0.428, P = 0.0013 and R2 = 0.501, P = 0.0003, respectively).
4

Analysis of nasal airway symmetry and pharyngeal airway following rapid maxillary expansion

DiCosimo, Charles 19 June 2018 (has links)
OBJECTIVES: This retrospective cohort study tested the effect of Rapid Maxillary Expansion (RME) on symmetrical volumetric changes in the nasal cavity. Volumetric changes in overall nasal cavity, nasopharynx, and oropharynx were also assessed as well as minimum cross-sectional width changes and molar angulation in association with RME. METHODS: CBCT scans of before and after RME treatment for 28 subjects (17 females, 11 males, average age 9.85 ± 2.42 years) were collected from a previously de-identified database. All subjects were treated for maxillary constriction using banded hyrax expanders. Mimics software was utilized to segment the nasal and pharyngeal airways and create various compartments (left and right nasal cavity, nasopharynx, and oropharynx) for volumetric analysis. Minimum cross-sectional width measurements and maxillary first molar angulation were also assessed. Paired T-test was used to quantify the changes brought about by expansion. Statistical significance was set at the 0.05 level. RESULTS: Posterior expansion as measured between right and left greater palatine foramen (GPF) averaged 2.41 mm (SD = 1.03 mm). There were statistically significant differences in overall nasal cavity (2249.6 ± 2102.5 mm3), right nasal cavity (968.8 ± 1082.7), left nasal cavity (1197.3 ± 1587.0), nasopharyngeal (1000.6 ± 917.7), and oropharyngeal (2349.2 ± 2520.8) volumes. In comparing the right to left nasal cavity, no significant changes were noted for initial volume, post-expansion volume, or pre to post-expansion changes (T2-T1). For cross-sectional analysis, the right nasal cavity (0.13 ± 0.07 mm) and left nasal cavity (0.11 ± 0.06 mm) showed significant increases in minimum crosssectional width measurements. Initial maxillary molar angulation had no significant correlation to initial nasal cavity volume on either side. CONCLUSIONS: RME has significant benefits to increasing nasal and pharyngeal airway cavity volumes in all segments of the airway. Nasal cavity expands symmetrically. Minimum cross-sectional width of the left and right nasal cavities showed highly symmetrical improvements. Initial maxillary molar angulation has no relationship to initial nasal cavity volume.
5

The comparison of different rapid maxillary expansion devices from periodontal tissue health and root resorption perspectives

Facciolo, Joseph 25 October 2017 (has links)
INTRODUCTION: Utilization of rapid maxillary expansion (RME) is common for the correction of sagittal discrepancies in orthodontic treatment. RME appliances will transmit a compressive force to the periodontal support structures. This resultant force can lead to resorption of the dento-alveolar structures leading to unwanted dental movements. The purpose of this retrospective study was to compare changes from a periodontal and root resorption perspective by means of computer tomography with tooth-borne and bonded expanders. METHODS: The sample comprised of cone beam computed tomography and spiral CT images of 41 subjects, 12 to 17 years old, with unilateral or bilateral posterior crossbites. 20 subjects treated previously with a bonded expander and 21 with a banded expander. Pre and post-treatment images were digitized and landmarks were identified to measure buccal and lingual cortex thickness, alveolar height, root length and angulation by means of a computerized method. RESULTS: RME with banded and bonded expanders have similar effects from periodontal and root resorption perspectives. Changes include increasing thickness of lingual alveolar bone 0.2 to 0.7 mm, decreases in buccal bone width 0.1 to 0.5 mm; and decreases in alveolar height 0.1 to 0.9 mm and root length 0.3 to 1.0mm of each support teeth. CONCLUSIONS: RME with banded and bonded expanders exhibited similar changes post-expansion and these variables should not play a role in selection of the type of device.
6

Analysis of skeletal and dental changes with a tooth-borne and a bone-borne maxillary expansion appliance assessed through digital volumetric imaging

Lagravere Vich, Manuel Oscar Unknown Date
No description available.
7

Analysis of skeletal and dental changes with a tooth-borne and a bone-borne maxillary expansion appliance assessed through digital volumetric imaging

Lagravere Vich, Manuel Oscar 11 1900 (has links)
The purpose of this research was to compare skeletal and dental changes assessed by digital volumetric images produced during and after rapid maxillary expansion (RME) between a bone-borne anchored expansion appliance and a conventional tooth-borne RME. Initial steps included the development of a methodology to analyze CBCT images. Reliability of traditional two dimensional (2D) cephalometric landmarks identified in CBCT images was explored, and new landmarks identifiable on the CBCT images were also evaluated. This methodology was later tested through a clinical trial with 62 patients where skeletal and dental changes found after maxillary expansion using either a bone-borne or tooth-borne maxillary expander and compared to a non-treated control group. The conclusions that were obtained from this thesis were that the NewTom 9” and 12” three dimensional (3D) images present a 1-to-1 ratio with real coordinates, linear and angular distances obtained by a coordinate measurement machine (CMM). Landmark intra- and inter-reliability (ICC) was high for all CBCT landmarks and for most of the 2D lateral cephalometric landmarks. Foramen Spinosum, foramen Ovale, foramen Rotundum and the Hypoglossal canal all provided excellent intra-observer reliability and accuracy. Midpoint between both foramen Spinosums (ELSA) presented a high intra-reliability and is an adequate landmark to be used as a reference point in 3D cephalometric analysis. ELSA, both AEM and DFM points presented a high intra-reliability when located on 3D images. Minor variations in location of these landmarks produced unacceptable uncertainty in coordinate system alignment. The potential error associated with location of distant landmarks is unacceptable for analysis of growth and treatment changes. Thus, an alternative is the use of vectors. Selection of landmarks for use in 3D image analysis should follow certain characteristics and modifications in their definitions should be applied. When measuring 3D maxillary complex structural changes during maxillary expansion treatments using CBCT, both tooth-anchored and bone-anchored expanders presented similar results. The greatest changes occurred in the transverse dimension while changes in the vertical and antero-posterior dimension were negligible. Dental expansion was also greater than skeletal expansion. Bone-anchored maxillary expanders can be considered as an alternative choice for tooth-anchored maxillary expanders. / Medical Sciences in Orthodontics
8

A EXPANSÃO RÁPIDA DAMAXILA COM HAAS E A FALA NA FISSURA / RAPID MAXILLARY EXPANSIONWITH HAAS AND THE SPEECH IN

Lazzari, Christiane Moraes 20 July 2007 (has links)
The aim of this study was verify the effects of rapid maxillary expansion (RME) with Haas, in speech of the pacient with transforamen cleft lip and palate. The sample consisted of 12 individuals with cleft lip and palate (CLP), being 6 boys and 6 girls, with age between 7 and 14 years, carriers of cleft lip and palate corrected with surgery. From these, 6 individuals, 3 boys and 3 girls, were submited to conventional activation ERM protocol (Group 1). The other 6 individuals, 3 boys and 3 girls, were submited to activation ERM protocol in agreement with Liou and Tsai (2005) of alternate expansions and constrictions (Group 2). The subjects were submited to fonoaudiologic evaluation of orofacial organs; nasal air capacity evaluation; perceptual analysis and spectographic evaluation of speech. The results obtained showed that RME produces changes on speech and orofacial organs in individuals with CLP. However, in some subjects, the changes did not happened in spite of RME structure changes. The increase of the nasal air capacity was statistically relevant. No statistically relevant was found between the groups in evaluations. The presente study indicated that RME produces changes on lips and tongue posture and breathing. These changes probably happen because an increase on intra-oral space, however the results showed that changes not always happen in a spontaneous way. / O objetivo deste estudo foi verificar os efeitos da Expansão Rápida da Maxila, com aparelho Haas, na fala do paciente com Fissura Labiopalatia Transforame. A amostra foi composta por 12 indivíduos com fissura lábiopalatina (FLP), sendo 6 do sexo masculino e 6 do sexo feminino, com faixa etária entre 7 e 14 anos de idade, com cirurgias primárias de reparo de lábio e palato. Do total de sujeitos, 6 indivíduos, 3 meninos e 3 meninas, foram submetidos à Expansão Rápida da Maxila (ERM) de acordo com protocolo de ativação convencional (Grupo 1). Os outros 6 indivíduos, 3 meninos e 3 meninas, foram submetidos à ERM com protocolo de ativação preconizado por Liou e Tsai (2005) com expansões e constrições alternadas (Grupo 2). Os sujeitos realizaram avaliações fonoaudiológicas das estruturas e funções orofaciais; avaliação da aeração nasal; e avaliação da fala através de análise perceptivo auditiva e análise acústica. Os resultados da pesquisa mostram que a ERM traz mudanças à fala e às estruturas orofaciais e respiração do indivíduo com FLP. Em muitos casos, porém, não houve modificações mesmo tendo havido mudanças do ponto de vista estrutural advindas da ERM. Não houve diferença estatisticamente significativa entre os dois grupos nos aspectos avaliados. Concluiuse que a ERM traz modificações como posicionamento de lábios, língua e, respiração. Esse fato foi atribuído ao aumento do espaço intraoral e espaço aéreo nasal, porém, os resultados mostram que as modificações nem sempre ocorrem de maneira espontânea.
9

Avaliação das vias aeríferas superiores, antes e após expansão rápida da maxila, utilizando Tomografia Computadorizada por Feixe Cônico / Assessment of upper airway before and after rapid maxillary expansion using Cone Beam Computed Tomography

Ribeiro, Annelise Nazareth Cunha 03 June 2011 (has links)
A respiração predominantemente oral é constantemente citada como um dos fatores associados ao desenvolvimento da deficiência transversal da maxila. A Expansão Rápida da Maxila (ERM) é um excelente método para a correção desta alteração, por meio da abertura da sutura palatina. A tomografia computadorizada por feixe cônico é tem sido descrita como um método preciso de exame de imagens e diante das limitações dos métodos radiográficos convencionais o objetivo deste estudo é avaliar as alterações morfológicas imediatas, decorrentes da ERM, na cavidade nasal e na região da naso e orofaringe, por meio da TCFC. Foram avaliadas 15 pares de imagens tomográfica, correspondentes a 15 pacientes portadores deficiência transversal da maxila, tratados com ERM, que realizaram a TCFC ao início e após o período de contenção de 4 meses. Os resultados encontrados mostram que a cavidade nasal apresenta aumento transversal significativo em seu terço inferior, nas regiões anterior (p=0,045), média (p=0,009) e posterior (p=0,001). Não há alteração significativa do volume (p=0,11), área sagital mediana (p=0,33) e menor área axial (p=0,29) decorrente da ERM na nasofaringe. Há alteração significativa do volume (p=0,05), área sagital mediana (p=0,01) e menor área axial (p=0,04) nos momentos antes e imediatamente após a ERM, na orofaringe. Após análise dos resultados concluímos que a ERM é capaz de aumentar a largura transversal da cavidade nasal, não tendo o mesmo efeito na região da nasofaringe, e que as alterações encontradas na orofaringe podem ser decorrentes de falta de padronização o posicionamento da cabeça e lingual no momento da aquisição da imagem. / The predominantly oral breathing is constantly cited as an etiological factor for the transverse maxillary deficiency. Rapid Maxillary Expansion is an excellent method for the correction of malocclusion, through the opening of the midpalatal sutures. The literature shows that the benefits of this procedure are beyond the dental benefits, and could have repercussions in the upper airways, due to its close relationship with the maxilla. The cone beam computed tomography has been described as is an accurate method of taking pictures and before the limitations of conventional radiographic methods the aim of this study is to evaluate the immediate morphological changes resulting from the ERM, the nasal cavity and the nasal region and oropharynx, through the CBCT. We evaluated 15 patients with maxillary width deficiency were treated with RME, which hosted the CBCT to the beginning and after the retention period of 3 months. The results show that the nasal cavity presents significant increase in cross their lower third, in the anterior (1.08 mm ± 0.15), medium (1.28 mm ± 0.15) and posterior (0.77 mm ± 0.12). No significant change in volume (p=0.11), median sagittal area (p=0.33) and lower axial area (p=0.29) resulting from the RME in nasopharynx. There is significant change in volume (p = 0.05), median sagittal area (p = 0.01) and lower axial area (p = 0.04) before and immediately after the RME in the oropharynx. After analysis and discussion of results in this study, we concluded that RME is able to increase the transverse width of the nasal cavity, not having the same effect in the nasopharynx, and that the changes found in the oropharynx may be due to the lack of positioning standardization of the head and tongue at the time of image acquisition.
10

Avaliação das vias aeríferas superiores, antes e após expansão rápida da maxila, utilizando Tomografia Computadorizada por Feixe Cônico / Assessment of upper airway before and after rapid maxillary expansion using Cone Beam Computed Tomography

Annelise Nazareth Cunha Ribeiro 03 June 2011 (has links)
A respiração predominantemente oral é constantemente citada como um dos fatores associados ao desenvolvimento da deficiência transversal da maxila. A Expansão Rápida da Maxila (ERM) é um excelente método para a correção desta alteração, por meio da abertura da sutura palatina. A tomografia computadorizada por feixe cônico é tem sido descrita como um método preciso de exame de imagens e diante das limitações dos métodos radiográficos convencionais o objetivo deste estudo é avaliar as alterações morfológicas imediatas, decorrentes da ERM, na cavidade nasal e na região da naso e orofaringe, por meio da TCFC. Foram avaliadas 15 pares de imagens tomográfica, correspondentes a 15 pacientes portadores deficiência transversal da maxila, tratados com ERM, que realizaram a TCFC ao início e após o período de contenção de 4 meses. Os resultados encontrados mostram que a cavidade nasal apresenta aumento transversal significativo em seu terço inferior, nas regiões anterior (p=0,045), média (p=0,009) e posterior (p=0,001). Não há alteração significativa do volume (p=0,11), área sagital mediana (p=0,33) e menor área axial (p=0,29) decorrente da ERM na nasofaringe. Há alteração significativa do volume (p=0,05), área sagital mediana (p=0,01) e menor área axial (p=0,04) nos momentos antes e imediatamente após a ERM, na orofaringe. Após análise dos resultados concluímos que a ERM é capaz de aumentar a largura transversal da cavidade nasal, não tendo o mesmo efeito na região da nasofaringe, e que as alterações encontradas na orofaringe podem ser decorrentes de falta de padronização o posicionamento da cabeça e lingual no momento da aquisição da imagem. / The predominantly oral breathing is constantly cited as an etiological factor for the transverse maxillary deficiency. Rapid Maxillary Expansion is an excellent method for the correction of malocclusion, through the opening of the midpalatal sutures. The literature shows that the benefits of this procedure are beyond the dental benefits, and could have repercussions in the upper airways, due to its close relationship with the maxilla. The cone beam computed tomography has been described as is an accurate method of taking pictures and before the limitations of conventional radiographic methods the aim of this study is to evaluate the immediate morphological changes resulting from the ERM, the nasal cavity and the nasal region and oropharynx, through the CBCT. We evaluated 15 patients with maxillary width deficiency were treated with RME, which hosted the CBCT to the beginning and after the retention period of 3 months. The results show that the nasal cavity presents significant increase in cross their lower third, in the anterior (1.08 mm ± 0.15), medium (1.28 mm ± 0.15) and posterior (0.77 mm ± 0.12). No significant change in volume (p=0.11), median sagittal area (p=0.33) and lower axial area (p=0.29) resulting from the RME in nasopharynx. There is significant change in volume (p = 0.05), median sagittal area (p = 0.01) and lower axial area (p = 0.04) before and immediately after the RME in the oropharynx. After analysis and discussion of results in this study, we concluded that RME is able to increase the transverse width of the nasal cavity, not having the same effect in the nasopharynx, and that the changes found in the oropharynx may be due to the lack of positioning standardization of the head and tongue at the time of image acquisition.

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