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1.
Ortho Sci., Orthod. sci. pract ; 14(56): 84-90, 2021. 84^c90
Article in Portuguese | BBO - Dentistry | ID: biblio-1352806

ABSTRACT

Resumo A inclinação mesial de molares permanentes é comumente observada e pode ser provocada por uma série de fatores, dentre os quais se destacam a perda precoce dos primeiros molares decíduos, perda dos primeiros molares permanentes e doenças periodontais. A seleção do dispositivo para correção desse problema depende do grau de inclinação e do tipo de movimento desejado. A eficiência mecânica e praticidade de confecção e instalação fazem da alça de correção radicular uma excelente alternativa para verticalização de molares. O objetivo desse trabalho foi relatar um caso clínico, em que se realizou a verticalização de quatro molares simultaneamente com alça de correção radicular apoiada em miniplacas. Paciente, 35 anos, sexo masculino, apresentou como queixa principal a insatisfação com a mastigação. Mediante análises clínica e radiográfica foi observada a perda precoce dos primeiros molares inferiores, que levou à inclinação severa dos dentes 37, 38, 47 e 48 com fechamento total do espaço correspondente aos dentes 36 e 46. O planejamento biomecânico consistiu na verticalização dos quatro molares simultaneamente por rotação pura empregando a alça de correção radicular ativada em GVI e ancorada em duas miniplacas instaladas na região anterior da mandíbula. No presente caso clínico, a utilização da alça de correção radicular ativada em geometria VI apresentou-se como uma boa alternativa mecânica, tendo em vista sua ativação simples, precisa e confortável para o paciente em casos, nos quais se faz necessária a verticalização de molares sem forças verticais atuantes no sistema. (AU)


Abstract The mesial inclination of permanent molars is commonly noticed and may be caused by several factors, including premature loss of the primary first deciduous molars, loss of the first permanent molars, periodontal disease. The device selection for correcting this condition depends on the degree of inclination and the desired movement. The mechanical efficiency and the easy manufacturing and installation make the root spring an excellent alternative for molar uprigthing. The objective of this study was to report the clinical case of a simultaneous verticalization of four molars with root spring anchored with miniplates. A 35 years-old male patient presented as main complaint dissatisfaction regarding chewing. Clinical and radiographic analysis showed the early loss of the first lower molars, which led to the inclination of teeth 37, 38, 47 and 48 with total closure of the space corresponding to teeth 36 and 46. The biomechanical planning consisted of the simultaneous uprigthing of the four molars with root spring activated in GVI and anchored in two miniplates installed in the anterior region of the mandible. In this clinical case report, the root spring activated in geometry VI showed to be a good mechanical alternative, as it is a simple, precise, and comfortable for the patient in cases in which molars uprigthing is necessary without vertical forces acting on the system. (AU)


Subject(s)
Humans , Male , Adult , Orthodontics , Tooth Movement Techniques , Orthodontic Anchorage Procedures , Molar
3.
Angle Orthod ; 87(4): 542-548, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28084785

ABSTRACT

OBJECTIVE: To evaluate the force systems produced by transpalatal arches (TPAs) activated according to the six classes of geometries described by Burstone and Koenig. MATERIALS AND METHODS: Sixty appliances were tested for first-order activations using a mechanical force testing system. The TPAs were first checked for passivity in sagittal, transverse, and vertical planes at the measuring machine. Then 10 appliances per group were activated using a millimeter template to obtain the six classes of geometries, and the activated appliances were inserted into lingual tubes of the Force System Identification machine that recorded the deactivation forces and moments delivered by both terminal ends of the TPAs. RESULTS: The overall force system with the actual values of forces and moments recorded by each type of activation was illustrated and compared with the mathematical model reported by Burstone and Koenig. Although a great consistency of the direction of forces and moments were observed, the theoretically feasible force systems could not be fully accomplished by the TPA activated for the six classes of geometries. CONCLUSION: The first-order activations of the TPA can deliver predictable force systems in respect to the direction of forces and moments attainable, but some unexpected forces and moments are also produced. Careful clinical monitoring is, therefore, strongly recommended when using this statically indeterminate system.


Subject(s)
Activator Appliances , Orthodontic Appliance Design , Tooth Movement Techniques/instrumentation , Dental Stress Analysis , Humans , Orthodontic Wires , Stainless Steel
4.
Am J Orthod Dentofacial Orthop ; 146(2): 198-206, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25085303

ABSTRACT

INTRODUCTION: The aim of this study was to use the finite element method to evaluate the distribution of stresses and strains on the local bone tissue adjacent to the miniplate used for anchorage of orthodontic forces. METHODS: A 3-dimensional model composed of a hemimandible and teeth was constructed using dental computed tomographic images, in which we assembled a miniplate with fixation screws. The uprighting and mesial movements of the mandibular second molar that was anchored with the miniplate were simulated. The miniplate was loaded with horizontal forces of 2, 5, and 15 N. A moment of 11.77 N·mm was also applied. The stress and strain distributions were analyzed, and their correlations with the bone remodeling criteria and miniplate stability were assessed. RESULTS: When orthodontic loads were applied, peak bone strain remained within the range of bone homeostasis (100-1500 µ strain) with a balance between bone formation and resorption. The maximum deformation was found to be 1035 µ strain with a force of 5 N. At a force of 15 N, bone resorption was observed in the region of the screws. CONCLUSIONS: We observed more stress concentration around the screws than in the cancellous bone. The levels of stress and strain increased when the force was increased but remained within physiologic levels. The anchorage system of miniplate and screws could withstand the orthodontic forces, which did not affect the stability of the miniplate.


Subject(s)
Bone Plates , Finite Element Analysis , Imaging, Three-Dimensional/methods , Mandible/physiology , Orthodontic Anchorage Procedures/instrumentation , Tooth Movement Techniques/instrumentation , Biomechanical Phenomena , Bone Remodeling/physiology , Bone Resorption/physiopathology , Computer Simulation , Homeostasis/physiology , Humans , Miniaturization , Models, Biological , Molar/pathology , Orthodontic Appliance Design , Stress, Mechanical , Surface Properties , Tomography, X-Ray Computed/methods
5.
Biosci. j. (Online) ; 30(4): 1259-1268, july/aug. 2014. ilus, graf, tab
Article in Portuguese | LILACS | ID: biblio-967572

ABSTRACT

O conhecimento sobre as propriedades mecânicas dos fios de Níquel-Titânio (NiTi) termoativados das marcas mais acessíveis do mercado nacional ainda é limitado. Diante disso, o objetivo deste estudo foi avaliar e comparar por meio de testes de deflexão em 03 braquetes, os fios NiTi termo ativados retangulares de calibre 0,014''x0,025'' e 0,016"x0,022" de diferentes marcas (MORELLI® ORMCO®, ORTHOSOURCE®, ORTHOMETRIC®, EURODONTO® e ADITEK®). Todos os testes foram realizados na máquina de ensaio universal EMIC DL 2000 sob condições idênticas e controladas a uma temperatura de 36°C ± 0,5°C. Cinco medições (N=5) foram realizadas para cada espessura/marca de fio que foi deflexionado até um limite de 4,0mm a uma velocidade de 1,0mm/min. A cada 0,2mm (ida e volta) de deflexão a força correspondente foi aferida para a construção do gráfico de força x deflexão no programa Tesc versão 3.04. Cada gráfico foi avaliado individualmente segundo as seguintes variáveis: início da transformação martensítica (cN e mm), força máxima (cN), inicio e final do platô de desativação (cN e mm) e comprimento do platô (mm). As médias e o desvio padrão foram calculados para todas as variáveis e a análise estatística foi feita pelos testes ANOVA 2 critérios e Turkey ou Kruskal-Wallis e Dunn, a um nível de significância de 5%. Os resultados evidenciaram que nos testes dos fios 0,014''x0,025'' as marcas ORTHOMETRIC® e ORMCO® apresentaram os melhores resultados, assim como os fios das marcas MORELLI® e ORTHOSOURCE® para os fios 0,016''x0,022''. De uma forma geral, os fios de calibre 0,014''x0,025'' apresentaram níveis de força no platô de desativação até 6 x menores que os de calibre 0,016''x0,022''.


The knowledge of the mechanical properties of nickel-titanium (NiTi) termoactives of the more accessible of the domestic market is still limited. Given this, the objective of this study was to evaluate and compare through deflection tests in brackets NiTi wires 03 term rectangular gauge 0.014" enabled x 0.025" and 0.016" x 0.022" of different brands (MORELLI®, ORMCO® ORTHOSOURCE®, ORTHOMETRIC®, EURODONTO® and ADITEK®). All tests were carried out on universal testing machine EMIC DL 2000 under identical conditions and controlled at a temperature of 36°C ± 0.5°C. Five measurements (N=5) were performed for each thickness/wire tag that was deflected up to a limit of 4.0mm at a speed of 1.0mm/min. Each 0.2mm (round trip) of corresponding strength measured deflection for the construction of the graph of force x deflection at Tesc program version 3.04. Each graphic was evaluated according to the following variables: beginning of the Martensitic transformation (cN and mm), maximum strength (cN), the beginning and end of the plateau of deactivation (cN and mm) and length (mm) plateau. The average and standard deviation were calculated for all variables and statistical analysis was made by ANOVA tests 2 criteria and Turkey or Kruskal-Wallis and Dunn, a 5% level of significance. The results showed that the tests of 0.014"x0.025" ORTHOMETRIC® brands and ORMCO® showed the best results, as well as the wires of the MORELLI® and ORTHOSOURCE® to wires 0.016"x0.022". In General, the gauge wires 0.014"x0.025" showed strength levels on the plateau of deactivation to 6 x smaller than 0.016"x0.022" caliber.


Subject(s)
Orthodontic Wires , Orthodontics
7.
Rev. Clín. Ortod. Dent. Press ; 12(5): 6-23, out.-nov. 2013. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: biblio-855945

ABSTRACT

utilização de implantes osseointegráveis como ancoragem para movimentação ortodôntica vem sendo empregada há muito tempo. Desde 1983, estudos em animais vem demonstrando que a utilização dos implantes como ancoragem não somente é viável, como também ajuda a aumentar a densidade óssea ao redor dos implantes. Nesses estudos, forças de até 5N (aproximadamente 500g) foram testadas sem gerar danos à estabilidade dos implantes, nem perdas ósseas na crista alveolar1,7,11,12,13,16,17,18,22,32. Em 1996, surgiu o Orthosystem, que consistia de um implante de 4 a 6mm de comprimento intraósseo e de 3,3mm de diâmetro, que era colocado no meio do palato e que servia de ancoragem direta e indireta para diversas movimentações ortodônticas. Com a popularização dos mini-implantes, esse sistema caiu em desuso, principalmente devido ao custo e ao fato da remoção ser mais difícil (era necessária a utilização de trefina), fazendo com que deixar o implante sepultado no palato, ao invés de removê-lo, se tornasse a melhor opção. Outra abordagem pouco utilizada atualmente são os implantes na região retromolar com o objetivo de distalizar molares inferiores. Esses também necessitavam ser removidos após seu uso.


Subject(s)
Humans , Female , Adult , Dental Implants , Orthodontic Anchorage Procedures/methods , Orthodontics
8.
Dental Press J Orthod ; 18(1): 150-7, 2013.
Article in English | MEDLINE | ID: mdl-23876963

ABSTRACT

OBJECTIVE: The objective of this study was to review the most recent studies from the last 15 years, in search of clinical studies that report the relationship between TMD and orthodontic treatment and/or malocclusion. Our intention was to determine whether orthodontic treatment would increase the incidence of signs and symptoms of TMD, and whether orthodontic treatment would be recommended for treating or preventing signs and symptoms of TMD. METHODS: Literature reviews, editorials, letters to the editor, experimental studies in animals and short communications were excluded from this review. Were included only prospective, longitudinal, case-control or retrospective studies with a large sample and significant statistical analysis. Studies that dealt with craniofacial deformities and syndromes or orthognathic surgery treatment were also excluded, as well as those that reported only the association between malocclusion and TMD. RESULTS: There were 20 articles relating orthodontics to TMD according to the inclusion criteria. The studies that associated signs and symptoms of TMD to orthodontic treatment showed discrepant results. Some have found positive effects of orthodontic treatment on signs and symptoms of TMD, however, none showed a statistically significant difference. CONCLUSIONS: All studies cited in this literature review reported that orthodontic treatment did not provide risk to the development of signs and symptoms of TMD, regardless of the technique used for treatment, the extraction or non-extraction of premolars and the type of malocclusion previously presented by the patient. Some studies with long-term follow-up concluded that orthodontic treatment would not be preventive or a treatment option for TMD.


Subject(s)
Malocclusion/complications , Orthodontics, Corrective/adverse effects , Temporomandibular Joint Disorders/etiology , Humans , Malocclusion/therapy
9.
Rev. Clín. Ortod. Dent. Press ; 12(3): 8-20, jun.-jul. 2013. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-707644

ABSTRACT

A Odontologia sofreu uma verdadeira revolução com a introdução dos implantes osseointegráveis. Hoje, o planejamento em reabilitação bucal é totalmente diferente do que era há 10 ou 20 anos. Atualmente, praticamente não existem mais próteses extensas em perdas dentárias parciais, e as próteses totais são apoiadas em implantes. De forma semelhante, a utilização de ancoragem esquelética e o desenvolvimento de novas ligas metálicas que possibilitam a liberação de forças leves e constantes revolucionaram a maneira de tratar os mais variados tipos de más oclusões em Ortodontia. A popularização dos mini-implantes e dos fios e molas de níquel-titânio possibilitou a diminuição dos custos, tornando esses materiais presentes na maioria dos consultórios ortodônticos...


Subject(s)
Humans , Female , Tooth Movement Techniques/methods , Orthodontic Anchorage Procedures/methods
10.
Dental press j. orthod. (Impr.) ; 18(1): 150-157, Jan.-Feb. 2013. tab
Article in English | LILACS | ID: lil-674277

ABSTRACT

OBJECTIVE: The objective of this study was to review the most recent studies from the last 15 years, in search of clinical studies that report the relationship between TMD and orthodontic treatment and/or malocclusion. Our intention was to determine whether orthodontic treatment would increase the incidence of signs and symptoms of TMD, and whether orthodontic treatment would be recommended for treating or preventing signs and symptoms of TMD. METHODS: Literature reviews, editorials, letters to the editor, experimental studies in animals and short communications were excluded from this review. Were included only prospective, longitudinal, case-control or retrospective studies with a large sample and significant statistical analysis. Studies that dealt with craniofacial deformities and syndromes or orthognathic surgery treatment were also excluded, as well as those that reported only the association between malocclusion and TMD. RESULTS: There were 20 articles relating orthodontics to TMD according to the inclusion criteria. The studies that associated signs and symptoms of TMD to orthodontic treatment showed discrepant results. Some have found positive effects of orthodontic treatment on signs and symptoms of TMD, however, none showed a statistically significant difference. CONCLUSIONS: All studies cited in this literature review reported that orthodontic treatment did not provide risk to the development of signs and symptoms of TMD, regardless of the technique used for treatment, the extraction or non-extraction of premolars and the type of malocclusion previously presented by the patient. Some studies with long-term follow-up concluded that orthodontic treatment would not be preventive or a treatment option for TMD.


OBJETIVO: revisar a literatura mais atual, dos últimos 15 anos, em busca de estudos clínicos que relatem a relação entre a disfunção temporomandibular (DTM) e o tratamento ortodôntico e/ou a má oclusão. A intenção foi verificar se o tratamento ortodôntico aumentaria o aparecimento de sinais e sintomas de DTM, e se o tratamento ortodôntico seria um recurso para o tratamento ou prevenção dos sinais e sintomas de DTM. MÉTODOS: artigos dos tipos revisão de literatura, editorial, carta, estudo experimental em animais e comunicação foram excluídos dessa revisão. Foram incluídos artigos prospectivos, longitudinais, caso-controle ou retrospectivo com amostra maior, com relevante análise estatística. Estudos que abordassem deformidades e síndromes craniofaciais e tratamento por cirurgia ortognática também foram excluídos, bem como aqueles que relatassem apenas a associação entre má oclusão e DTM. RESULTADOS: foram encontrados 20 artigos relacionando Ortodontia à DTM, segundo os critérios adotados. Os estudos, então, associando sinais e sintomas de DTM ao tratamento ortodôntico apresentaram resultados heterogêneos. Alguns encontraram efeitos positivos do tratamento ortodôntico para os sinais e sintomas de DTM; entretanto, nenhum deles apresentou diferença estatisticamente significativa. CONCLUSÕES: todos os estudos citados nessa revisão de literatura relataram que o tratamento ortodôntico não forneceu risco ao desenvolvimento de sinais e sintomas de DTM, independentemente da técnica utilizada para tratamento, da exodontia ou não de pré-molares e do tipo de má oclusão previamente apresentada pelo paciente. Alguns estudos realizados com acompanhamento em longo prazo concluíram que o tratamento ortodôntico não seria preventivo ou uma modalidade de tratamento para DTM.


Subject(s)
Humans , Malocclusion/complications , Orthodontics, Corrective/adverse effects , Temporomandibular Joint Disorders/etiology , Malocclusion/therapy
11.
Ortodontia ; 45(6): 703-712, nov.-dez. 2012. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-714068

ABSTRACT

Este artigo apresenta uma nova técnica de tratamento, queutiliza arcos de TMA com curvas padronizadas, associados a elásticosintermaxilares que, ao mesmo tempo, oferece resultados satisfatóriosem um período de tratamento relativamente curto no tratamento dasmordidas abertas e na finalização do tratamento ortodôntico.


This study presents a new treatment technique, thatuses TMAarchwires with standardized curvatures, associated to intermaxillaryelastics, that can do both offer satisfactory results in shortperiod of the treatment time in the open bites cases and in the finishingprocedures of the orthodontic treatment.


Subject(s)
Humans , Male , Female , Young Adult , Orthodontic Appliances/adverse effects , Orthodontic Wires , Molybdenum , Titanium , Treatment Outcome
12.
13.
Rev. dent. press ortodon. ortopedi. facial ; 14(1): 103-116, jan.-fev. 2009. ilus
Article in Portuguese | LILACS | ID: lil-503884

ABSTRACT

Este trabalho descreve uma nova forma de ancoragem por meio de miniplacas denominada SAO®, Sistema de Apoio Ósseo para Mecânica Ortodôntica. Após a descrição do sistema, protocolos de tratamento para mordidas abertas esqueléticas são apresentados. A aplicação de cantiléveres e alças apoiadas diretamente nos tubos do sistema de ancoragem permite que associações de problemas verticais e sagitais (Classe II e III) sejam tratadas de formas distintas. A aplicação de forças leves e constantes e o controle tridimensional das forças aplicadas são o grande diferencial desse novo sistema.


This paper describes the SAO®, Sistema de Apoio Ósseo para Mecânica Ortodôntica (Skeletal Supported System for Orthodontic Mechanics), a new approach for anchorage by means of mini-plates. After the description of the system, treatment protocols for skeletal openbite cases are presented. The use of cantilevers and different spring configurations attached directly in the tubes of the anchorage system allows various approaches for vertical and sagittal discrepancies.


Subject(s)
Humans , Dental Implants , Malocclusion , Orthodontic Anchorage Procedures/methods , Clinical Protocols , Dental Materials , Photography
14.
Rev. Clín. Ortod. Dent. Press ; 6(6): 32-36, dez. 2007-jan. 2008. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-495621

ABSTRACT

Com o advento dos aparelhos pré-ajustados, o procedimento da colagem dos braquetes ganhou importância, pois a diminuição de falhas de posicionamento durante esse processo tem como resultado um tratamento ortodôntico com maior rapidez e tranqüilidade para o profissional, evitando a necessidade de dobras no arco de finalização. O objetivo deste artigo é demonstrar uma técnica, que se destaca por ser simples e muito conveniente para a nossa realidade, pelo custo final.


Subject(s)
Orthodontic Brackets , Dental Bonding/methods
15.
Eur J Orthod ; 28(3): 282-91, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16199409

ABSTRACT

Thermodynamic nickel-titanium (NiTi) wires have become increasingly popular. The relationship between the temperature variation within the mouth and the force level delivered is, however, far from elucidated. The aim of this study was to evaluate the influence of possible intraoral temperature differences on the forces exerted by seven commercially available 0.019 x 0.025 inch NiTi archwires. As mouth temperature ranges from 33 to 37 degrees C most of the time, all wires were tested at five different temperatures between 30 and 40 degrees C in an orthodontic wire-testing device, a so-called Force System Identification (FSI) apparatus, placed in a climate chamber. In the FSI a two-bracket system using self-ligating Damon brackets simulated first order displacements up to 4 mm. At each temperature five samples of each archwire brand were tested. The following variables from the activation/deactivation curves were calculated: force and displacement at the yield point, maximum force level, total energy up to maximum displacement, energy loss after deactivation, force and displacement at the beginning and at the finish of the plateau, and the slope of the plateau. Any statistically significant differences in these variables for the different brands and temperature levels were analysed using one-way analysis of variance. The results showed that: (1) The behaviour of all wires was different. (2) Copper NiTi40 showed the lowest and the most constant force level, followed by NeoSentalloy 200 g. On the other hand, these wires may not work properly in mouth breathers as no forces were exerted below 35 degrees C. (3) If the use of superelastic characteristics and low force levels are the reasons for utilizing rectangular NiTi wires, austenitic NiTi wires should be avoided.


Subject(s)
Hot Temperature , Nickel/chemistry , Orthodontic Wires , Titanium/chemistry , Copper/chemistry , Materials Testing
16.
Angle Orthod ; 75(4): 499-505, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16097216

ABSTRACT

The soft tissue changes after the extraction of maxillary first premolars and subsequent anterior tooth retraction were evaluated for 16 Class II, division 1 patients. Pre- and posttreatment lateral head cephalograms were evaluated using superimpositions on Björk-type metallic implants in the maxilla. The patient sample was divided into group I patients, those who did exhibit lip seal at rest in the pretreatment cephalogram and group II patients, those who did not exhibit lip seal at rest in the pretreatment cephalogram. Upper incisor retraction was followed by a similar ratio of upper lip retraction in both the lip seal and nonsealed groups (1:0.75 and 1:0.70 mean ratios, respectively). However, those without lip seal did demonstrate more retraction at stomion (USt). The final upper lip position (Ls) was reasonably correlated with retraction of the cervical maxillary incisor point (cU1) with determination coefficients of 63.6% in the lip sealed and 68.5% in the lip incompetent groups. Although labial and nasolabial angles tended to open after incisor retraction, there was little predictability for this response.


Subject(s)
Dental Implants , Incisor , Lip/anatomy & histology , Malocclusion, Angle Class II/therapy , Tooth Movement Techniques , Bicuspid/surgery , Cephalometry , Female , Humans , Male , Maxilla , Maxillofacial Development , Orthodontic Appliances , Tantalum , Tooth Extraction , Tooth Movement Techniques/instrumentation , Tooth Movement Techniques/methods
17.
Rev. dent. press ortodon. ortopedi. facial ; 10(1): 139-157, jan.-fev. 2005. ilus, tab, graf
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-413480

ABSTRACT

O objetivo deste artigo é descrever a análise cefalométrica que vem sendo aplicada nos cursos de mestrado, doutorado e especialização da Faculdade de Odontologia de Araraquara - UNESP. A mesma foi desenvolvida utilizando medidas cefalométricas já existentes e descritas na literatura as quais foram agrupadas em campo a fim de permitir que o profissional faça a interpretação adequada de cada área e tenha, no final da mesma, todas as informações necessárias para um correto diagnóstico e plano de tratamento. Da mesma forma, após o tratamento, a comparação das diferentes medidas e áreas de análise permitirão a interpretação de quais foram os efeitos provocados pelo tratamento aplicado


Subject(s)
Humans , Cephalometry
18.
J. bras. ortodon. ortop. facial ; 10(55): 50-58, jan.-fev. 2005. ilus, tab
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-495656

ABSTRACT

O fechamento de espaços é uma rotina no consultório ortodôntico. Existem vários recursos para se realizar tal manobra, mas na maioria destes não se conhece o sistema de forças liberado. Nesse trabalho, procurou-se descrever o sistema de forças liberadas pela alça T com pré-ativações recomendadas por Marcotte para o grupo B de ancoragem. Para isso, foram feitos testes de tração utilizando máquina universal de ensaio e um transdutor de momentos aclopado a um indicador digital para extensometria. A alça foi posicionada centralizada no espaço entre os acessórios e foi feita uma ativação inicial de 7mm. A alça foi desativada a cada 0,5mm, sendo obtida a leitura da força horizontal e do momento gerado. Os resultados mostraram uma força horizontal inicial de 297,7g e uma proporção Momento/Força de 7,1 sendo que o movimento de translação ocorreu a partir de 2,5mm de desativação, e a correção radicular com 3,5mm de desativação. Frente aos resultados obtidos, indica-se a utilização desta alça para retração de caninos, incisivos e retração total, devendo ser reativada a cada 3,5mm de desativação.


Subject(s)
Biomechanical Phenomena , Orthodontic Space Closure , Orthodontics, Corrective , Tooth Movement Techniques/methods , Orthodontic Anchorage Procedures/methods
19.
Rev. dent. press ortodon. ortopedi. facial ; 9(6): 33-38, nov.-dez. 2004. ilus, tab
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-412525

ABSTRACT

Neste artigo é descrito o caso clínico de um paciente adulto, sem crescimento, com má oclusão de Classe II, divisão 2, tratado com um splint maxilar modificado. Foi exercida força extrabucal com direção de tração parietal com força de 400 gramas, com uso diário de 14 horas durante 1 ano. Com este aparelho removível corrigiu-se completamente a relação de Classe II dos molares e pré-molares, levando estes dentes à oclusão normal, não havendo extrusão dentária, mantendo constante o plano mandibular. Após a correção dos dentes posteriores com o splint maxilar modificado, utilizou-se aparelhagem fixa convencional para corrigir as inclinações dos dentes anteriores e finalizar o caso


Subject(s)
Humans , Male , Adult , Malocclusion, Angle Class II/therapy , Orthodontic Appliances , Orthodontics , Orthodontics, Corrective
20.
Am J Orthod Dentofacial Orthop ; 126(3): 344-53, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15356499

ABSTRACT

Assessment of the exact position of the posterior teeth on lateral headfilms is of limited validity because of the superimposition of the 2 sides. Lateral headfilms are also of limited use for evaluating orthodontic tooth movement, especially in cases of asymmetric mechanics. To solve this problem, the oblique cephalometric radiograph, which brings only 1 side of the image into focus, was introduced. We evaluated whether the projection of the cranial base could be used for evaluating facial growth and whether structures that were stable relative to the implants could be identified and thus replace the implants in future evaluations. Thirty sets of headfilms from growing patients with metallic implants were analyzed. Three types of superimpositions were performed. Displacement of the metallic implants in the maxillary complex and the mandible with respect to the superimposed structures of the cranial base was evaluated. When the development of the lateral parts of the facial skeleton was evaluated in relation to the cranial base, the reproducibility of the superimpositioning was significantly better in the vertical-S(e) = 0.41-than in the horizontal plane of space-S(e) = 1.35). The error of the method when superimposed on the stable structures in the maxillary complex varied between 0.31 and 0.72 and did not differ in the vertical and sagittal directions. In the mandible, the stable structures suggested for superimposition of the lateral headfilms were applicable on the oblique cephalometric radiograph-S(e) = 0.33-0.57. Oblique projection is recommended when individual analysis of the 2 sides is needed.


Subject(s)
Cephalometry/methods , Dental Implants , Maxilla/diagnostic imaging , Radiography, Dental/methods , Tooth Movement Techniques/methods , Adolescent , Child , Female , Humans , Jaw Relation Record , Male , Mandible/anatomy & histology , Mandible/diagnostic imaging , Mandible/growth & development , Maxilla/anatomy & histology , Maxilla/growth & development , Maxillofacial Development/physiology , Orthodontics, Corrective/methods , Reproducibility of Results , Vertical Dimension
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