L'organisation orientationnelle bio-moléculaire des lipides et des protéines dans la membrane plasmique constitue un facteur important dans les processus biologiques au cours desquelles les fonctions peuvent être reliées aux mécanismes d'orientation et d'organisation. Le concept de séparation transitoire des phases à l'échelle nanométrique dans les domaines ordonnés et désordonnés, aussi appelé « radeau lipidique », est maintenant largement accepté. De plus, les domaines ordonnés contiennent des protéines de signalisation, ce qui souligne l'importance des séparations de phase au cours des processus de signalisation. Dans cette thèse de doctorat, nous avons étudié l'ordre orientationnel moléculaire de la protéine de signalisation MHC Class I et de reporters lipidiques tels que di-8-ANEPPQ et DiI(C18). Nous avons étudié l'ordre orientationnel moléculaire de la protéine de signalisation MHC Class I et des reporters lipidiques par imagerie d'anisotropie de fluorescence résolue en polarisation. Nous avons observé l'influence du cytosquelette d'actine sur l'ordre orientationnel moléculaire de la protéine MHC et des reporters lipidiques dans la membrane plasmique. De plus, nous avons trouvé que l'ordre orientationnel moléculaire des reporters dépend de la morphologie cellulaire. Nous avons examiné les plis membranaires en modifiant la forme des cellules de façon mécanique ou pharmacologique. / Biomolecular orientational organization of lipids and proteins in the plasma membrane is a crucial factor in biological processes where functions can be closely related to orientation and ordering mechanisms. The concept of transient nanosized phase separations in ordered and disordered domains, called "lipid rafts" is now widely accepted. Furthermore, the ordered domains are enriched in signaling proteins, which highlights the crucial impact of phase separation during the signaling processes. While this field has been so far largely addressed by studying the translational diffusion behavior of membrane proteins and lipid reporters by Single Molecule Tracking (SMT) or Fluorescence Correlation Spectroscopy (FCS), only little is known about the orientational behavior of signaling proteins and lipid reporters in the plasma membrane. In this PhD thesis we investigated the molecular orientational order of the signaling molecule MHC Class I protein using fluorescence anisotropy imaging as well as of lipid reporter di-8-ANEPPQ using polarization-resolved fluorescence imaging. Fluorescence anisotropy imaging requires a fluorescent label rigidly attached to the system under study, able to report its orientational order behavior. Thus, MHC Class I protein has been successfully labeled in a rigid way. We analyzed the orientational order of MHC Class I protein quantitatively in the endomembrane and plasma membrane and we found that the orientational order of MHC Class I protein in both membranes depends primarily on the maturation state of the protein and its interaction with the cytoskeleton.

This thesis is comprised of studies of proteins involved in class I and class II major histocompatibility complex (MHC) antigen procressing. In class I MHC processing, structural and functional studies were conducted of an aminopeptidase, ERAP1, that mediates the final step in antigen processing to understand how it is particularly suitable for cleavage of antigenic peptides for class I MHC presentation. In the class II MHC antigen presentation pathway, structural studies were conducted to characterize a fluorogenic peptide that can be used to understand peptide loading events in vivo and in real time. Also structural studies of class II MHC and peptide complexes were conducted to understand the nature of an unique C-terminal secondary structure element exhibited by an HIV derived peptide in the peptide binding groove of class II MHC. The studies discussed in this thesis provide insights into the proteins involved in the class I and class II MHC antigen presentation pathway. The endoplasmic reticulum (ER) aminopeptidase, ERAP1, is a 941 amino acid member of the M1 family of zinc metalloaminopeptidases. Unlike other aminopeptidases, ERAP1 has a length and C-terminal preference for its substrates. Interestingly, ERAP1 has been shown to trim antigenic peptides to lengths of 8 or 9 amino acids long. This length matches the length required to bind into the peptide binding groove of class I MHC molecules. In addition, ERAP1 is upregulated in the ER of cells treated with interferon gamma (IFN-γ). Knock-down of ERAP1 by siRNA results in less overall antigenic presentation during IFN-γ treatment, although the knock-down does not affect all class I MHC epitopes equally. Knock-out studies show that ERAP1 effects the antigen repertoire at the cell surface. These and other data implicate ERAP1 as an important player in class I MHC antigen presentation. A chapter of this thesis will describe the crystallographic work describing the structures of ERAP1 with an aminopeptidase inhibitor, bestatin, and ERAP1 without an inhibitor that suggest possible peptide binding site in ERAP1 that will allow it to generate suitable substrates for a subset of class I MHC alleles. Class II MHC plays a key role in the immune response by presenting antigenic peptides on CD4+ cytotoxic cell surfaces for T-cell response. The binding of peptides onto the MHC is an important step in creating an immune response. Structures of peptide bound MHC class II show conserved side chain binding pockets within the overall peptide-binding groove. In HLA-DR1, a common human class II MHC, the P1 pocket shows a preference for large hydrophobic side chains. Development of environmentally sensitive peptide analogs, that can bind into the class II MHC the same way as native peptides, can assist in visualizing the antigen binding process. A chapter in this thesis describes the crystallographic work showing that (4-DAPA)-HA can be used to study antigen-presenting processes in a cell by visualizing the changes in fluorescence of the synthesized peptide upon antigen loading. Crystallographic analysis of MHC class II, HLA-DR1, in complex with HIV gag-derived peptide, GagP16(PEVIPMFSALSEGATP), and superantigen, SEC3- 3B2, reveals the conventional polyproline conformation up to MHC binding pocket residue, P9, while the C-terminus of GagP16 adopts an unusual β- hairpin loop structure. Additionally, interactions between the leucine at P8 (LeuP8) and other residues on the loop such as ThrP16 and AlaP14 of the hairpin loop, was observed. Importantly, GagP16 requires the last 4 amino acids (P13-P16), which is part of the hairpin loop, for T-cell recognition. Understanding what dictates the C-terminal hairpin loop and the interaction motif of HLA-DR1/GagP16 complex with its TCR will provide insights on why it is important for T cell activation. A chapter in this thesis discusses the structural investigation conducted to understand the determinants of the loop at the C-terminus of GagP16 using designed peptides. It will also discuss work involving HLA-DR1 with the T cell receptor, AC25, that was cloned from T cells that are specific to HLA-DR1 in complex with the GagP16 peptide.

PURPPOSE: The objective of this research was to measure MVS between the central incisors and the posterior areas to evaluate whether computer designed guides can be used. MATERIALS AND METHODS: A total of 150 adult subjects (aged 22−78) were included. The population was further stratified by race, sex and Angle Classification. The examiner measured the maximum vertical space (MVS) at six specific sites. Measurements were repeated twice at each site. In addition overbite and ovejet were measured at the central incisor position. The pilot drill/guide appliance combination space requirement was tested with each category of MVS measurement. RESULTS: (i) there was a race effect, with African American having a greater maximum vertical space measurement than Caucasian and Asian respectively (P < 0.0001); (ii) there was a also gender effect, with males having a greater maximum vertical space measurement than females(P < 0.0001); (iii) there was an inverse association with overjet on central incisors and first premolars, with less overjet subjects having a greater maximum vertical space measurement (P < 0.05). We found that overall only 76% of the female cohort in our sample satisfied this space requirement of Nobel Guide (45mm) at the central incisor position. SUMMARY: Using the Nobel computer guided surgery minimum dimension requirement of 45mm, our findings suggest that first premolar or second molar implants could not be placed in our sample of dentulous patients, while a central incisor implant could be placed in 76%-100% of subjects depending on gender and race factors.

O objetivo desta pesquisa foi realizar um estudo cefalométrico radiográfico com o propósito de avaliar as mudanças no perfil tegumentar do terço inferior da face em casos com maloclusões de Classe I, biprotrusos, tratados ortodonticamente com extrações de quatro premolares, por meio da técnica do arco contínuo preconizada por Roth. A amostra constou de 56 radiografias cefalométricas de 26 pacientes leucodermas chilenos, com média de idade de 19,56 + 5,71 anos tomadas ao início e ao término do tratamento. Foram mensuradas as variações na espessura e comprimento do perfil tegumentar, bem como as alterações posturais anteroposteriores dento-alveolares e tegumentares ocorridas. Foram realizadas comparações entre os valores iniciais e finais e correlações entre as variações das grandezas analisadas por meio de análises estatísticas. Após análise dos resultados concluiu-se que, após a retração dos dentes anteriores, a espessura do lábio superior apresentou aumento na sua porção basal e na região do vermelhão labial, enquanto que sua porção intermediária não apresentou variação estatisticamente significante. No lábio inferior, somente a espessura do vermelhão do lábio inferior apresentou aumento significativo. O comprimento total do lábio superior também apresentou aumento estatisticamente significante, enquanto que no comprimento do lábio inferior não foi observado aumento significante. Os lábios superior e inferior sofreram retração estatisticamente significante e o movimento de retração do vermelhão do lábio superior correlacionou diretamente com o movimento do incisivo superior, tanto em nível incisal (0,33:1), como em nível coronário (0,57:1), assim como o movimento de retração do sulco do lábio superior que correlacionou diretamente com o movimento do incisivo superior, tanto em nível incisal (0,26:1) como em nível coronário (0,42:1). O movimento de retração do vermelhão do lábio inferior correlacionou diretamente não só com o movimento da incisal do incisivo inferior (0,54:1) como também com o movimento do incisivo superior tanto em nível incisal (0,57:1), como em nível coronário (0,85:1). Não se constatou correlação entre a alteração postural dos lábios e as alterações tegumentares de espessura e comprimento em todas as variáveis estudadas, exceto a variação do ângulo mentolabial que correlacionou com a variação do comprimento da base do lábio inferior. Essas duas variáveis, no entanto, não apresentaram alterações significativas. / The purpose of this prospective cephalometric study was to evaluate soft tissue profile changes in biprotrusive Class I patients treated with first premolars extractions and maximum anchorage control. The sample was composed of 52 lateral cephalometric roentgenogram from the beginnig and end of treatment of 26 white chilean patients (18 females and 8 males) with age average of 19,56 + 5,71 years old, treated with Roth straight-wire technique. Linear and angular cephalometric values in relation to thickness, lengths, lips posture, convexity of the skeletal and integumental profile, as well as incisors and alveolar profile points posture were evaluated. After statistical analysis, the results showed that upper lip thickness increased in the vermillion and basal area. Lower lip thickness also increased in the vermillion area. Upper lip total length increased while lower lip showed no change in its length. The retraction of the lips as well as the incisors were significant. Upper incisor retraction correlated with upper lip vermillion retraction at the incisor border (0,33 mm :1 mm) and at the crown level (0,57 mm : 1mm). Likewise it was verified with the upper lip sulcus (point A?), that retracted on a proportion of 0,26 mm : 1mm at the upper incisor border level and 0,42 mm : 1 mm at the crown level. Lower lip vermillion retraction correlated with lower incisor retraction at the incisor border level (0,54:1) as well as with upper incisor retraction at the incisor border (0,57:1) and at the crown level (0,85:1). Lip postural changes did not correlated with lip length or thickness changes except lower lip basal length that correlated with the increase of mentolabial angle.

Com o objetivo de contribuir com a literatura acerca da prevalência e etiologia da reabertura de espaços de extrações após o tratamento ortodôntico, o presente trabalho se propôs a: verificar a prevalência em casos de má oclusão de Classe I tratados com extrações de quatro primeiros pré-molares; identificar o arco de maior ocorrência; avaliar o comportamento desses espaços no período de 1 e 5 anos póstratamento; verificar a associação com fatores como a quantidade de apinhamento anteroinferior, quantidade de retração dos incisivos inferiores e angulação entre coroas de caninos e segundos pré-molares ao final do tratamento. A amostra deste estudo longitudinal foi composta por documentações ortodônticas de 54 indivíduos tratados na clínica de Ortodontia da Faculdade de Odontologia de Bauru, Universidade de São Paulo. A amostra foi dividida em dois grupos: Grupo 1, composto por casos em que houve a reabertura de espaços de extração no período pós-tratamento; e Grupo 2, composto por casos em que não houve a reabertura de espaços. Os modelos foram digitalizados mediante um scanner 3Shape R700 3D (3Shape A/S,Copenhagen, Dinamarca), e mensurados através do software OrthoAnalyzerTM 3D. A mensuração da quantidade de retração dos incisivos inferiores durante o tratamento foi realizada através das telerradiografias inicias e finais, utilizando o programa Dolphin®Imaging 11.5 (Chatsworth, CA, EUA). As alterações interfases dos espaços foram avaliadas por meio do teste de Friedman e o teste de McNemar. O teste t independente foi utilizado para a comparação intergrupos. Todos os testes estatísticos utilizaram o nível de significância de p<0,05. Os resultados mostraram que 33,33% da amostra apresentou reabertura de espaços de extração, com prevalência maior no arco superior. Houve tendência de fechamento dos espaços no período de 5 anos pós-tratamento. O grupo com reabertura apresentou menor apinhamento inicial e maior quantidade de retração dos incisivos inferiores durante o tratamento. Não houve diferença entre os grupos quanto à angulação final de caninos e segundos pré-molares. / In order to contribute with orthodontic literature upon extraction space reopening prevalence and etiology, this studys aim is: to verify the prevalence of extraction space reopening after orthodontic treatment of Class I malocclusion with four first premolar extractions; to identify the arch with higher occurrence; to evaluate the space changes in 1 and 5 years after treatment; to seek for associations with other clinical aspects such as initial mandibular crowding, amount of mandibular incisors retraction during treatment and angulation between canines and second premolars crowns. The sample of this long-term study comprised orthodontic records of 54 patients, who were treated in the clinic of Orthodontics of Bauru Dental School University of Sao Paulo. This sample was divided into two groups: Group 1, consisted of at least one extraction space reopening and group 2, without space reopening. The casts were digitalized by a 3D 3Shape R700 scanner (3Shape A/S,Copenhagen, Denmark) and measured on OrthoAnalyzerTM 3D software. Initial and final cephalometric radiographs were analyzed using Dolphin®Imaging 11.5 (Chatsworth, CA, USA) to measure the amount of mandibular incisors retraction during treatment. Quantitative changes of extraction sites over time were compared by Friedmans test and qualitative changes by McNemars test. T tests were used to compare the groups. The significance level for all statistics tests was p <0.05. Results showed that 33.33% of the complete sample demonstrated space reopening in the posttreatment period, with higher prevalence in the maxillary arch. The amount and frequency of the spaces tended to decrease 5 years after the end of treatment. Patients with space reopening had less initial anterior crowding and an increased amount of mandibular incisor retraction during treatment. Final neighboring tooth angulations were similar in both groups.

Com o objetivo de contribuir com a literatura acerca da prevalência e etiologia da reabertura de espaços de extrações após o tratamento ortodôntico, o presente trabalho se propôs a: verificar a prevalência em casos de má oclusão de Classe I tratados com extrações de quatro primeiros pré-molares; identificar o arco de maior ocorrência; avaliar o comportamento desses espaços no período de 1 e 5 anos póstratamento; verificar a associação com fatores como a quantidade de apinhamento anteroinferior, quantidade de retração dos incisivos inferiores e angulação entre coroas de caninos e segundos pré-molares ao final do tratamento. A amostra deste estudo longitudinal foi composta por documentações ortodônticas de 54 indivíduos tratados na clínica de Ortodontia da Faculdade de Odontologia de Bauru, Universidade de São Paulo. A amostra foi dividida em dois grupos: Grupo 1, composto por casos em que houve a reabertura de espaços de extração no período pós-tratamento; e Grupo 2, composto por casos em que não houve a reabertura de espaços. Os modelos foram digitalizados mediante um scanner 3Shape R700 3D (3Shape A/S,Copenhagen, Dinamarca), e mensurados através do software OrthoAnalyzerTM 3D. A mensuração da quantidade de retração dos incisivos inferiores durante o tratamento foi realizada através das telerradiografias inicias e finais, utilizando o programa Dolphin®Imaging 11.5 (Chatsworth, CA, EUA). As alterações interfases dos espaços foram avaliadas por meio do teste de Friedman e o teste de McNemar. O teste t independente foi utilizado para a comparação intergrupos. Todos os testes estatísticos utilizaram o nível de significância de p<0,05. Os resultados mostraram que 33,33% da amostra apresentou reabertura de espaços de extração, com prevalência maior no arco superior. Houve tendência de fechamento dos espaços no período de 5 anos pós-tratamento. O grupo com reabertura apresentou menor apinhamento inicial e maior quantidade de retração dos incisivos inferiores durante o tratamento. Não houve diferença entre os grupos quanto à angulação final de caninos e segundos pré-molares. / In order to contribute with orthodontic literature upon extraction space reopening prevalence and etiology, this studys aim is: to verify the prevalence of extraction space reopening after orthodontic treatment of Class I malocclusion with four first premolar extractions; to identify the arch with higher occurrence; to evaluate the space changes in 1 and 5 years after treatment; to seek for associations with other clinical aspects such as initial mandibular crowding, amount of mandibular incisors retraction during treatment and angulation between canines and second premolars crowns. The sample of this long-term study comprised orthodontic records of 54 patients, who were treated in the clinic of Orthodontics of Bauru Dental School University of Sao Paulo. This sample was divided into two groups: Group 1, consisted of at least one extraction space reopening and group 2, without space reopening. The casts were digitalized by a 3D 3Shape R700 scanner (3Shape A/S,Copenhagen, Denmark) and measured on OrthoAnalyzerTM 3D software. Initial and final cephalometric radiographs were analyzed using Dolphin®Imaging 11.5 (Chatsworth, CA, USA) to measure the amount of mandibular incisors retraction during treatment. Quantitative changes of extraction sites over time were compared by Friedmans test and qualitative changes by McNemars test. T tests were used to compare the groups. The significance level for all statistics tests was p <0.05. Results showed that 33.33% of the complete sample demonstrated space reopening in the posttreatment period, with higher prevalence in the maxillary arch. The amount and frequency of the spaces tended to decrease 5 years after the end of treatment. Patients with space reopening had less initial anterior crowding and an increased amount of mandibular incisor retraction during treatment. Final neighboring tooth angulations were similar in both groups.

O objetivo desta pesquisa foi realizar um estudo cefalométrico radiográfico com o propósito de avaliar as mudanças no perfil tegumentar do terço inferior da face em casos com maloclusões de Classe I, biprotrusos, tratados ortodonticamente com extrações de quatro premolares, por meio da técnica do arco contínuo preconizada por Roth. A amostra constou de 56 radiografias cefalométricas de 26 pacientes leucodermas chilenos, com média de idade de 19,56 + 5,71 anos tomadas ao início e ao término do tratamento. Foram mensuradas as variações na espessura e comprimento do perfil tegumentar, bem como as alterações posturais anteroposteriores dento-alveolares e tegumentares ocorridas. Foram realizadas comparações entre os valores iniciais e finais e correlações entre as variações das grandezas analisadas por meio de análises estatísticas. Após análise dos resultados concluiu-se que, após a retração dos dentes anteriores, a espessura do lábio superior apresentou aumento na sua porção basal e na região do vermelhão labial, enquanto que sua porção intermediária não apresentou variação estatisticamente significante. No lábio inferior, somente a espessura do vermelhão do lábio inferior apresentou aumento significativo. O comprimento total do lábio superior também apresentou aumento estatisticamente significante, enquanto que no comprimento do lábio inferior não foi observado aumento significante. Os lábios superior e inferior sofreram retração estatisticamente significante e o movimento de retração do vermelhão do lábio superior correlacionou diretamente com o movimento do incisivo superior, tanto em nível incisal (0,33:1), como em nível coronário (0,57:1), assim como o movimento de retração do sulco do lábio superior que correlacionou diretamente com o movimento do incisivo superior, tanto em nível incisal (0,26:1) como em nível coronário (0,42:1). O movimento de retração do vermelhão do lábio inferior correlacionou diretamente não só com o movimento da incisal do incisivo inferior (0,54:1) como também com o movimento do incisivo superior tanto em nível incisal (0,57:1), como em nível coronário (0,85:1). Não se constatou correlação entre a alteração postural dos lábios e as alterações tegumentares de espessura e comprimento em todas as variáveis estudadas, exceto a variação do ângulo mentolabial que correlacionou com a variação do comprimento da base do lábio inferior. Essas duas variáveis, no entanto, não apresentaram alterações significativas. / The purpose of this prospective cephalometric study was to evaluate soft tissue profile changes in biprotrusive Class I patients treated with first premolars extractions and maximum anchorage control. The sample was composed of 52 lateral cephalometric roentgenogram from the beginnig and end of treatment of 26 white chilean patients (18 females and 8 males) with age average of 19,56 + 5,71 years old, treated with Roth straight-wire technique. Linear and angular cephalometric values in relation to thickness, lengths, lips posture, convexity of the skeletal and integumental profile, as well as incisors and alveolar profile points posture were evaluated. After statistical analysis, the results showed that upper lip thickness increased in the vermillion and basal area. Lower lip thickness also increased in the vermillion area. Upper lip total length increased while lower lip showed no change in its length. The retraction of the lips as well as the incisors were significant. Upper incisor retraction correlated with upper lip vermillion retraction at the incisor border (0,33 mm :1 mm) and at the crown level (0,57 mm : 1mm). Likewise it was verified with the upper lip sulcus (point A?), that retracted on a proportion of 0,26 mm : 1mm at the upper incisor border level and 0,42 mm : 1 mm at the crown level. Lower lip vermillion retraction correlated with lower incisor retraction at the incisor border level (0,54:1) as well as with upper incisor retraction at the incisor border (0,57:1) and at the crown level (0,85:1). Lip postural changes did not correlated with lip length or thickness changes except lower lip basal length that correlated with the increase of mentolabial angle.

My dissertation hypothesis is that bovine trophoblast cells express cell-surface and secreted non-classical major histocompatibility complex class I (MHC-Ib) proteins which inhibit NK cells and other leukocytes by binding to inhibitory receptors (e.g., LILRB1, LILRB2, KIR2DL4, and/or CD94/NKG2A). Extremely polymorphic and ubiquitously expressed classical MHC class I (MHC-Ia) proteins, which present foreign antigenic peptides to CD8+ T lymphocytes, are involved in acceptance or rejection of tissue grafts. Non-classical MHC class I (MHC-Ib) glycoproteins, such as Human Leukocyte Antigen-G (HLA-G) and murine Qa-2, are important modulators of the maternal immune system during pregnancy. MHC-Ib proteins are: (a) oligomorphic or monomorphic, (b) expressed in specific tissues under specific condtions, and (c) produced as surface and/or soluble isoforms due to alternative splicing. Third trimester-bovine trophoblast cells express both MHC-Ia and MHC-Ib proteins. The MHC-Ib proteins expressed by trophoblast cells during the third trimester of pregnancy are encoded by four bovine leukocyte antigen (BoLA) loci: BoLA-NC1, BoLA-NC2, BoLA-NC3, and BoLA-NC4. Two MHC-Ia (N*01701 and N*01802) and three MHC-Ib (NC1*00501, NC3*00101 and NC4*00201) proteins showed cell-surface expression in transfection studies performed in murine P815 and human K562 cells. Two additional isoforms, NC1*00401 and NC2*00102, were not detected on the surface of these cells. Nevertheless, both class Ia proteins, N*01701 and N*01802, and five class Ib proteins, NC1*00401, NC1*00501, NC2*00102, NC3*00101, and NC4*00201, were detected in crude cell lysates on Western blots. Precipitation of proteins from culture supernatants showed that cell-surface MHC-Ia (N*01701 and N*01802) and MHC-Ib proteins (NC1*00501, NC3*00101, and NC4*00201) are shed from the surface of these cells into the media. The mechanism of shedding of these proteins is, however, not known. Monoclonal antibodies W6/32, IL-A88, H1A, H6A, H11A, H58A, and PT-85A recognized surface MHC-I isoforms with varying affinity. We were able to develop a sandwich enzyme-linked immunosorbent assay (ELISA) using either H1A or IL-A88 antibody as the capture antibody and the W6/32 antibody for detection. We produced monoclonal antibodies against cattle NC1*00501 and NC3*00101 proteins. One monoclonal antibody generated against BoLA-NC3*00101 was highly specific. Unfortunately, due to failure to clone the NC3*00101- hybridoma, we no longer have an infinite source of this monoclonal antibody for NC3*00101. We eluted peptides from NC3*00101-transfected MHC-null K562 cells and identified peptides using liquid chromatography-mass spectrum (LC-MS) analysis. Analysis of peptide binding data using the SAS Proc mixed statistical program, suggested that the peptide EVTNQLVVL is a potential peptide ligand, which can be used to make tetramers for enumeration of antigen-specific leukocytes.

Introduction: The aim of this research was to compare the microesthetics characteristics of the maxillary anterior tooth in individuals with Class I malocclusion treated with four premolars extractions in relation to normal occlusion as well the evaluation of symmetry between right and left sides in both groups. Methods: The sample was divided into two groups, first one with Angle Class I malocclusion treated with four premolars extraction (mean age of 15.18 and composed by 22 female and 9 male patients), and second one with Normal Occlusion (mean age of 16.93 and comprised by 15 female and 16 male individuals) composed by 31 individuals each. Objective grading system index (OGS) was evaluated in the plaster models of both groups and then digitized in 3D 3Shape R700 scanner (3Shape A/S, Copenhagen, Denmark). The width/height proportion of anterosuperior teeth, zenith location, height of connectors and gingival contour were measured with OrthoAnalyzer 3D program. Random and systematic errors were respectively evaluated with Dahlbergs formula and paired t tests. Mann-Whitney U and t tests were applied to variables without and with normal distribution respectively. Results: In most comparison there was no significant differences between groups. It was noticed in a few situations that Class I group presented significantly greater width/height proportion in 12 than Normal Occlusion; significantly smaller gingival zenith of 23, significantly greater connector in 22 to 23 and also significantly greater gingival contour in right side in comparison to Normal Occlusion group. Both sides of Class I and Normal Occlusion groups presented symmetry. Conclusion: Four premolar extractions orthodontic treatment of Class I malocclusion provides similar microesthetic patterns as individuals with normal occlusion. Both groups generally present symmetric microesthetic characteristics. / Introdução: O objetivo desta pesquisa foi comparar as características de microestética nos dentes anterossuperiores em indivíduos com má oclusão de Classe I tratados com quatro extrações de pré-molares em relação à oclusão normal, bem como a avaliação da simetria entre os lados direito e esquerdo em ambos os grupos. Métodos: A amostra foi dividida em dois grupos, o primeiro com pacientes com má oclusão de Classe I de Angle tratados com extração de quatro pré-molares (idade média de 15,18 e composta por 22 pacientes do sexo feminino e 9 do sexo masculino) e um com Oclusão Normal (média de 16,93 e composto por 15 indivíduos do sexo feminino e 16 do sexo masculino) compostos por 31 indivíduos cada. O Objective Grading System Index (OGS) foi avaliado nos modelos de gesso dos dois grupos, os quais foram digitalizados em seguida no scanner 3D 3Shape R700 (3Shape A / S, Copenhagen, Dinamarca). A proporção largura / altura dos dentes anterossuperiores, a localização do zênite, a altura dos conectores e o contorno gengival foram medidos com o programa OrthoAnalyzer 3D. Erros casuais e sistemáticos foram avaliados respectivamente com a fórmula de Dahlberg e testes t pareados. Os testes U e t de Mann-Whitney foram aplicados às variáveis sem e com distribuição normal, respectivamente. Resultados: Na maioria das comparações não houve diferenças significativas entre os grupos. Percebeu-se que o grupo com Classe I apresentou proporção de largura / altura significativamente maior no incisivo lateral direito em relação à oclusão normal; zênite gengival significativamente menor no canino esquerdo, significativamente maior no conector entre o incisivo lateral esquerdo e canino esquerdo, e significativamente maior no contorno gengival do lado direito em comparação ao grupo de oclusão normal. Ambos os lados dos grupos Classe I e Oclusão Normal apresentaram simetria. Conclusão: O tratamento ortodôntico com extrações de quatro pré-molares da má oclusão de Classe I fornece padrões microestésicos semelhantes aos indivíduos com oclusão normal. Ambos os grupos apresentaram simetria na maioria das características de microestética.

Thesis--University of Oklahoma. / Includes bibliographical references (leaves 78-80).