900 resultados para Angle class II
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This article describes the multidisciplinary treatment of an adult patient presenting with Angle Class III malocclusion, alteration of the mandibular position, vertical alveolar bone loss and absence of teeth in the lower posterior region. With advancing age the existence of occlusal interference due to loss of teeth or tooth structure is very common, resulting in periodontal problems due to occlusal trauma. The options for treatment of Class III malocclusion in adolescent and adult patients include compensatory orthodontic treatment in mild to moderate cases and orthognathic surgery for moderate to severe cases. The combination of various dental specialties enabled improvement in the social circumstances of the patient. This can be observed objectively by the final dental relationship and by the skeletal and tegumentary cephalometric comparison between the situation at the beginning and at the end of the treatment. The compensatory treatment performed permitted the successful correction of a Class III malocclusion in the clinical case presented.
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Because it still brings polemic among the professionals, it was mention once more, in this literature review, the theme that aims to define the appropriate timing to approach the bad occlusions of Class II, and also when it would the right opportunity to treat them, in way that would convey to the patient consistent, stable results in a long term. These are important aspects to be taken into consideration by orthodontists, either by those who defend the early treatment or by those who defend the late treatment. Therefore, the present study aims to aid the clarification of daily doubts regarding this aspect.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The Dengue has become a global public health threat, with over 100 million infections annually; to date there is no specific vaccine or any antiviral drug. The structures of the envelope (E) proteins of the four known serotype of the dengue virus (DENV) are already known, but there are insufficient molecular details of their structural behavior in solution in the distinct environmental conditions in which the DENVs are submitted, from the digestive tract of the mosquito up to its replication inside the host cell. Such detailed knowledge becomes important because of the multifunctional character of the E protein: it mediates the early events in cell entry, via receptor endocytosis and, as a class II protein, participates determinately in the process of membrane fusion. The proposed infection mechanism asserts that once in the endosome, at low pH, the E homodimers dissociate and insert into the endosomal lipid membrane, after an extensive conformational change, mainly on the relative arrangement of its three domains. In this work we employ all-atom explicit solvent Molecular Dynamics simulations to specify the thermodynamic conditions in that the E proteins are induced to experience extensive structural changes, such as during the process of reducing pH. We study the structural behavior of the E protein monomer at acid pH solution of distinct ionic strength. Extensive simulations are carried out with all the histidine residues in its full protonated form at four distinct ionic strengths. The results are analyzed in detail from structural and energetic perspectives, and the virtual protein movements are described by means of the principal component analyses. As the main result, we found that at acid pH and physiological ionic strength, the E protein suffers a major structural change; for lower or higher ionic strengths, the crystal structure is essentially maintained along of all extensive simulations. On the other hand, at basic pH, when all histidine residues are in the unprotonated form, the protein structure is very stable for ionic strengths ranging from 0 to 225 mM. Therefore, our findings support the hypothesis that the histidines constitute the hot points that induce configurational changes of E protein in acid pH, and give extra motivation to the development of new ideas for antivirus compound design.
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Introduction: The aims of this meta-analysis were to quantify and to compare the amounts of distalization and anchorage loss of conventional and skeletal anchorage methods in the correction of Class II malocclusion with intraoral distalizers. Methods: The literature was searched through 5 electronic databases, and inclusion criteria were applied. Articles that presented pretreatment and posttreatment cephalometric values were preferred. Quality assessments of the studies were performed. The averages and standard deviations of molar and premolar effects were extracted from the studies to perform a meta-analysis. Results: After applying the inclusion and exclusion criteria, 40 studies were included in the systematic review. After the quality analysis, 2 articles were classified as high quality, 27 as medium quality, and 11 as low quality. For the meta-analysis, 6 studies were included, and they showed average molar distalization amounts of 3.34 mm with conventional anchorage and 5.10 mm with skeletal anchorage. The meta-analysis of premolar movement showed estimates of combined effects of 2.30 mm (mesialization) in studies with conventional anchorage and 4.01 mm (distalization) in studies with skeletal anchorage. Conclusions: There was scientific evidence that both anchorage systems are effective for distalization; however, with skeletal anchorage, there was no anchorage loss when direct anchorage was used.
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Introduction: The aim of this study was to compare the dentoskeletal changes of patients with Class II Division 1 malocclusion treated with either the Jasper jumper appliance or the activator-headgear combination, both associated with fixed appliances. Methods: The sample comprised 72 subjects with Class II Division 1 malocclusion divided into 3 groups: group 1 included 25 subjects treated with fixed appliances and the force modules of the Jasper jumper at an initial mean age of 12.72 years, group 2 included 25 subjects treated with the activator-headgear combination followed by fixed appliances at an initial mean age of 11.07 years, and group 3 included 22 untreated subjects at an initial mean age of 12.67 years. Initial cephalometric characteristics and dentoskeletal changes were compared with analysis of variance. Results: Both experimental groups had similar dentoskeletal changes: restrictive effect on the maxilla, clockwise mandibular rotation and a slight increase in anterior face height, retrusion of the maxillary incisors, distalization of the maxillary molars, protrusion of the mandibular incisors, extrusion of the mandibular molars, and significant improvements of the maxillomandibular relationship, overjet, overbite, and the molar relationship. Conclusions: The effects of the Jasper jumper and the activator-headgear combination followed by fixed orthodontic appliances were similar in Class II malocclusion treatment.
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Biorelevante Medien sind entwickelt worden, um die Bedingungen im Magen-Darm-Trakt vor und nach der Mahlzeit zu imitieren. Mit FaSSIF und FeSSIF wurden Medien eingeführt, die nicht nur die pH- und Puffer-Kapazität des Dünndarms widerspiegeln, sondern auch Lipid und physiologische Tensid-Arten enthalten. Diese Medien (FaSSIF-V2 und FaSSlFmod6.5) wurden für Bioverfügbarkeitstudien in der Medikamentenentwicklung im Laufe der Jahre kontinuierlich weiterentwickelt. Dennoch sind die auf dem Markt verfügbaren Medien immer noch nicht in der Lage, die realen physiologischen Bedingungen zu simulieren. In der jetzigen Zusammensetzung sind nicht alle Kompetenten enthalten, welche natürlicher Weise im Duodenum vorkommen. Darüber hinaus wird nur eine 1:5 Verdünnung von FeSSIF zu FaSSIF angenommen, die individuelle Wasserzufuhr bei Medikamentengabe wird hierdurch jedoch nur eingeschränkt simuliert, obwohl diese von Patient zu Patient schwanken kann. rnZiel dieser Dissertation war die Verbesserung der Vorhersage der Auflösung und Absorption lipophiler Arzneistoffe durch Simulation der Bedingungen im zweiten Teil des Zwölffingerdarms mit neuen biorelevanten Medien, sowie unter Einwirkung zusätzlicher Detergention als Wirkstoffträger. rnUm den Effekt der Verdünnungsrate und Zeit im Dünndarm zu untersuchen, wurde die Entwicklung der Nanopartikel in der Magen-Darm-Flüssigkeit FaSSIFmod6.5 zu verschiedenen Zeitpunkten und Wassergehalten untersucht. Dafür wurden kinetische Studien an verschieden konzentrierten Modellmedien nach Verdünnungssprung untersucht. Das Modell entspricht der Vermischung der Gallenflüssigkeit mit dem Darminhalt bei variablem Volumen. Die Ergebnisse zeigen, dass Art und Größe der Nanopartikel stark von Verdünnung und Einirkungszeit abhängen. rnrnDie menschliche Darmflüssigkeit enthält Cholesterin, welches in allen früheren Modellmedien fehlt. Daher wurden biokompatible und physiologische Modellflüssigkeiten, FaSSIF-C, entwickelt. Der Cholesteringehalt von FaSSIF - 7C entspricht der Gallenflüssigkeit einer gesunden Frau, FaSSIF - 10C der einer gesunden männlichen Person und FaSSIF - 13C der in einigen Krankheitszuständen. Die intestinale Teilchen-Struktur-Untersuchung mit dynamische Lichtstreuung (DLS) und Neutronen-Kleinwinkelstreuung (SANS) ergab, dass die Korngröße von Vesikeln mit zunehmender Cholesterin-Konzentration abnahm. Zu hohe Cholesterin-Konzentration bewirkte zusätzlich sehr große Partikel, welche vermutlich aus Cholesterin-reichen “Disks“ bestehen. Die Löslichkeiten einiger BCS Klasse II Wirkstoffe (Fenofibrat, Griseofulvin, Carbamazepin, Danazol) in diesen neuen Medien zeigten, dass die Löslichkeit in unterschiedlicher Weise mit der Cholesteringehalt zusammen hing und dieser Effekt selektiv für die Droge war. rnDarüber hinaus wurde die Wirkung von einigen Tensiden auf die kolloidale Struktur und Löslichkeit von Fenofibrat in FaSSIFmod6.5 und FaSSIF -7C untersucht. Struktur und Löslichkeit waren Tensid- und Konzentrations-abhängig. Im Falle von FaSSIFmod6.5 zeigten die Ergebnisse eine dreifache Verzweigung der Lösungswege. Im Bereich mittlerer Tensidkonzentration wurde eine Löslichkeitslücke der Droge zwischen der Zerstörung der Galle-Liposomen und der Bildung von Tensid-reichen Mizellen beobachtet. In FaSSIF - 7C, zerstörten Tenside in höherer Konzentration die Liposomenstruktur trotz der allgemeinen Stabilisierung der Membranen durch Cholesterin. rnDie in dieser Arbeit vorgestellten Ergebnisse ergeben, dass die Anwesenheit von Cholesterin als eine fehlende Komponente der menschlichen Darmflüssigkeit in biorelevanten Medien wichtig ist und dazu beitragen kann, das in vivo Verhalten schwerlöslicher Arzneistoffe im Körper besser vorhersagen zu können. Der Verdünnungsgrad hat einen Einfluss auf die Nanopartikel-Struktur und Tenside beeinflussen die Löslichkeit von Medikamenten in biorelevanten Medien: Dieser Effekt ist sowohl von der Konzentration das Tensids abhängig, als auch dessen Typ.rnrn
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This study analyzes short- and long-term skeletal relapse after mandibular advancement surgery and determines its contributing factors. Thirty-two consecutive patients were treated for skeletal Class II malocclusion during the period between 1986 and 1989. They all had combined orthodontic and surgical treatment with BSSO and rigid fixation excluding other surgery. Of these, 15 patients (47%) were available for a long-term cephalography in 2000. The measurement was performed based on the serial cephalograms taken preoperatively; 1 week, 6 months and 14 months postoperatively; and at the final evaluation after an average of 12 years. Mean mandibular advancement was 4.1 mm at B-point and 4.9 mm at pogonion. Representing surgical mandibular ramus displacement, gonion moved downwards 2 mm immediately after surgery. During the short-term postoperative period, mandibular corpus length decreased only 0.5 mm, indicating that there was no osteotomy slippage. After the first year of observation, skeletal relapse was 1.3 mm at B-point and pogonion. The relapse continued, reaching a total of 2.3 mm after 12 years, corresponding to 50% of the mandibular advancement. Mandibular ramus length continuously decreased 1 mm during the same observation period, indicating progressive condylar resorption. No significant relationship between the amount of initial surgical advancement and skeletal relapse was found. Preoperative high mandibulo-nasal plane (ML-NL) angle appears to be associated with long-term skeletal relapse.
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OBJECTIVE: The aim of this study was to estimate intra- and post-operative risk using the American Society of Anaesthesiologists (ASA) classification which is an important predictor of an intervention and of the entire operating programme. STUDY DESIGN: In this retrospective study, 4435 consecutive patients undergoing elective and emergency surgery at the Gynaecological Clinic of the University Hospital of Zurich were included. The ASA classification for pre-operative risk assessment was determined by an anaesthesiologist after a thorough physical examination. We observed several pre-, intra- and post-operative parameters, such as age, body-mass-index, duration of anaesthesia, duration of surgery, blood loss, duration of post-operative stay, complicated post-operative course, morbidity and mortality. The investigation of different risk factors was achieved by a multiple linear regression model for log-transformed duration of hospitalisation. RESULTS: Age and obesity were responsible for a higher ASA classification. ASA grade correlates with the duration of anaesthesia and the duration of the surgery itself. There was a significant difference in blood loss between ASA grades I (113+/-195 ml) and III (222+/-470 ml) and between classes II (176+/-432 ml) and III. The duration of post-operative hospitalisation could also be correlated with ASA class. ASA class I=1.7+/-3.0 days, ASA class II=3.6+/-4.3 days, ASA class III=6.8+/-8.2 days, and ASA class IV=6.2+/-3.9 days. The mean post-operative in-hospital stay was 2.5+/-4.0 days without complications, and 8.7+/-6.7 days with post-operative complications. Multiple linear regression model showed that not only the ASA classification contained an important information for the duration of hospitalisation. Parameters such as age, class of diagnosis, post-operative complications, etc. also have an influence on the duration of hospitalisation. CONCLUSION: This study shows that the ASA classification can be used as a good and early available predictor for the planning of an intervention in gynaecological surgery. The ASA classification helps the surgeon to assess the peri-operative risk profile of which important information can be derived for the planning of the operation programme.
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PURPOSE: The purpose of this systematic review was to evaluate horizontal relapse and its causes in bilateral sagittal split advancement osteotomy (BSSO) with rigid internal fixation of different types. MATERIALS AND METHODS: A search of the literature was performed in the databases PubMed, Ovid, Cochrane Library, and Google Scholar Beta. From 488 articles identified, 24 articles were finally included. Six studies were prospective, and 18 were retrospective. The range of postoperative study records was 6 months to 12.7 years. RESULTS: The short-term relapse for bicortical screws was between 1.5% and 32.7%, for miniplates between 1.5% and 18.0%, and for bioresorbable bicortical screws between 10.4% and 17.4%, at point B. The long-term relapse for bicortical screws was between 2.0% and 50.3%, and for miniplates between 1.5% and 8.9%, at point B. CONCLUSIONS: BSSO for mandibular advancement is a good treatment option for skeletal Class II, but seems less stable than BSSO setback in the short and long terms. Bicortical screws of titanium, stainless steel, or bioresorbable material show little difference regarding skeletal stability compared with miniplates in the short term. A greater number of studies with larger skeletal long-term relapse rates were evident in patients treated with bicortical screws instead of miniplates. The etiology of relapse is multifactorial, involving the proper seating of the condyles, the amount of advancement, the soft tissue and muscles, the mandibular plane angle, the remaining growth and remodeling, the skill of the surgeon, and preoperative age. Patients with a low mandibular plane angle have increased vertical relapse, whereas patients with a high mandibular plane angle have more horizontal relapse. Advancements in the range of 6 to 7 mm or more predispose to horizontal relapse. To obtain reliable scientific evidence, further short-term and long-term research into BSSO advancement with rigid internal fixation should exclude additional surgery, ie, genioplasty or maxillary surgery, and include a prospective study or randomized clinical trial design with correlation statistics.
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Restoration of the tumor-suppression function by gene transfer of the melanoma differentiation-associated gene 7 (MDA7)/interleukin 24 (IL-24) successfully induces apoptosis in melanoma tumors in vivo. To address the molecular mechanisms involved, we previously revealed that MDA7/IL-24 treatment of melanoma cells down-regulates interferon regulatory factor (IRF)-1 expression and concomitantly up-regulates IRF-2 expression, which competes with the activity of IRF-1 and reverses the induction of IRF-1-regulated inducible nitric oxide synthase (iNOS). Interferons (IFNs) influence melanoma cell survival by modulating apoptosis. A class I IFN (IFN-alpha) has been approved for the treatment of advanced melanoma with some limited success. A class II IFN (IFN-gamma), on the other hand, supports melanoma cell survival, possibly through constitutive activation of iNOS expression. We therefore conducted this study to explore the molecular pathways of MDA7/IL-24 regulation of apoptosis via the intracellular induction of IFNs in melanoma. We hypothesized that the restoration of the MDA7/IL-24 axis leads to upregulation of class I IFNs and induction of the apoptotic cascade. We found that MDA7/IL-24 induces the secretion of endogenous IFN-beta, another class I IFN, leading to the arrest of melanoma cell growth and apoptosis. We also identified a series of apoptotic markers that play a role in this pathway, including the regulation of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and Fas-FasL. In summary, we described a novel pathway of MDA7/IL-24 regulation of apoptosis in melanoma tumors via endogenous IFN-beta induction followed by IRF regulation and TRAIL/FasL system activation.
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OBJECTIVE Narcolepsy with cataplexy is tightly associated with the HLA class II allele DQB1*06:02. Evidence indicates a complex contribution of HLA class II genes to narcolepsy susceptibility with a recent independent association with HLA-DPB1. The cause of narcolepsy is supposed be an autoimmune attack against hypocretin-producing neurons. Despite the strong association with HLA class II, there is no evidence for CD4+ T-cell-mediated mechanism in narcolepsy. Since neurons express class I and not class II molecules, the final effector immune cells involved might include class I-restricted CD8+ T-cells. DESIGN HLA class I (A, B, and C) and II (DQB1) genotypes were analyzed in 944 European narcolepsy with cataplexy patients and in 4043 control subjects matched by country of origin. All patients and controls were DQB1*06:02 positive and class I associations were conditioned on DQB1 alleles. RESULTS HLA-A*11:01 (OR = 1.49 [1.18-1.87] P = 7.0*10-4), C*04:01 (OR = 1.34 [1.10-1.63] P = 3.23*10-3), and B*35:01 (OR=1.46 [1.13-1.89] P = 3.64*10-3) were associated with susceptibility to narcolepsy. Analysis of polymorphic class I amino-acids revealed even stronger associations with key antigen-binding residues HLA-A-Tyr9 (OR = 1.32 [1.15-1.52] P = 6.95*10-5) and HLA-C-Ser11 (OR=1.34 [1.15-1.57] P = 2.43*10-4). CONCLUSIONS Our findings provide a genetic basis for increased susceptibility to infectious factors or an immune cytotoxic mechanism in narcolepsy, potentially targeting hypocretin neurons.
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A assimetria das arcadas dentárias constitui um assunto de grande importância estudado por profissionais de Ortodontia na elaboração de um diagnóstico correto, planejamento e execução de um tratamento ortodôntico bem sucedido. O objetivo deste estudo foi avaliar o grau de assimetria das arcadas dentárias em indivíduos com oclusão normal e má oclusão de Classe II, divisão 1 e 2, bem como o dimorfismo sexual existente. Foram avaliados 180 pares de modelos de estudo de indivíduos do sexo masculino e feminino, na faixa etária de 12 a 21 anos, divididos em 3 grupos de 60 pares de modelos, de acordo com a má oclusão. Os grupos foram classificados em: Grupo 1 - indivíduos com oclusão normal, Grupo 2 - indivíduos com má oclusão de Classe II divisão 1 (Cl II 1), e Grupo 3 - indivíduos com má oclusão de Classe II divisão 2 (Cl II 2). Os modelos foram medidos utilizando-se um aparelho inédito, idealizado e fabricado exclusivamente para a análise de assimetria das arcadas dentárias. Para a análise de assimetria foram realizadas 2 medições angulares desvio de linha média (DLM), posicionamento dos caninos (PC) e 3 lineares distância dos caninos à rafe palatina (DC), distância inter-caninos (DIC), posicionamento dos primeiros molares no sentido ântero-posterior (PM). Concluiu-se que a ocorrência de assimetria nas arcadas dentárias independe da má oclusão. O Grupo 1 apresentou um menor grau de assimetria nas arcadas dentárias em relação aos grupos 2 e 3, os quais apresentaram um grau de assimetria semelhante. O grau de assimetria nas arcadas dentárias inferiores, nos 3 grupos, foi maior do que nas arcadas dentárias superiores. A direção do desvio da linha média apresentou uma correlação inversamente proporcional do lado em que o molar se apresentava mesializado, nas arcadas superior e inferior dos três grupos, com exceção da arcada superior no Grupo 2 (Classe II divisão 1). Houve dimorfismo sexual estatisticamente significante para algumas medidas, porém é importante considerar os baixos valores e a disposição, destas diferenças, entre as medidas realizadas, a qual revela ter se tratado de dados obtidos ao acaso.
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A assimetria das arcadas dentárias constitui um assunto de grande importância estudado por profissionais de Ortodontia na elaboração de um diagnóstico correto, planejamento e execução de um tratamento ortodôntico bem sucedido. O objetivo deste estudo foi avaliar o grau de assimetria das arcadas dentárias em indivíduos com oclusão normal e má oclusão de Classe II, divisão 1 e 2, bem como o dimorfismo sexual existente. Foram avaliados 180 pares de modelos de estudo de indivíduos do sexo masculino e feminino, na faixa etária de 12 a 21 anos, divididos em 3 grupos de 60 pares de modelos, de acordo com a má oclusão. Os grupos foram classificados em: Grupo 1 - indivíduos com oclusão normal, Grupo 2 - indivíduos com má oclusão de Classe II divisão 1 (Cl II 1), e Grupo 3 - indivíduos com má oclusão de Classe II divisão 2 (Cl II 2). Os modelos foram medidos utilizando-se um aparelho inédito, idealizado e fabricado exclusivamente para a análise de assimetria das arcadas dentárias. Para a análise de assimetria foram realizadas 2 medições angulares desvio de linha média (DLM), posicionamento dos caninos (PC) e 3 lineares distância dos caninos à rafe palatina (DC), distância inter-caninos (DIC), posicionamento dos primeiros molares no sentido ântero-posterior (PM). Concluiu-se que a ocorrência de assimetria nas arcadas dentárias independe da má oclusão. O Grupo 1 apresentou um menor grau de assimetria nas arcadas dentárias em relação aos grupos 2 e 3, os quais apresentaram um grau de assimetria semelhante. O grau de assimetria nas arcadas dentárias inferiores, nos 3 grupos, foi maior do que nas arcadas dentárias superiores. A direção do desvio da linha média apresentou uma correlação inversamente proporcional do lado em que o molar se apresentava mesializado, nas arcadas superior e inferior dos três grupos, com exceção da arcada superior no Grupo 2 (Classe II divisão 1). Houve dimorfismo sexual estatisticamente significante para algumas medidas, porém é importante considerar os baixos valores e a disposição, destas diferenças, entre as medidas realizadas, a qual revela ter se tratado de dados obtidos ao acaso.
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Este estudo avaliou o posicionamento ântero posterior dos primeiros molares inferiores, durante o tratamento ortodôntico, utilizando o arco lingual inferior como acessório de ancoragem na técnica Straight-Wire, em comparação aos casos tratados pela técnica Edgewise, sem a utilização do arco lingual. Dois grupos foram selecionados, ambos apresentando má oclusão de Classe I de Angle7, tratados com extração dos primeiros pré-molares superiores e inferiores. Foi utilizada uma amostra de 255 telerradiografias em norma lateral, obtidas de pacientes brasileiros, de ambos os sexos, com média de idade de 13 anos e 6 meses e com diferentes padrões de crescimento facial. Embasado na análise e discussão dos resultados, concluiu-se que: 1) do início do tratamento ao fim da fase de nivelamento, a perda de ancoragem coronária do primeiro molar inferior foi maior nos casos tratados com a técnica Straight-Wire; 2) do fim da fase de nivelamento ao fim do tratamento, a perda de ancoragem coronária e radicular do primeiro molar inferior foi maior na técnica Edgewise; 3) do início ao fim tratamento a perda de ancoragem radicular foi maior nos pacientes tratados com a técnica Edgewise; e 4) o deslocamento ântero-posterior dos incisivos inferiores não apresentou diferença estatisticamente significante para ambas as técnicas, em todas as etapas observadas.(AU)