Description of body posture during Static load bearing exercises for individuals with transfemoral amputation fitted with bone-anchored prosthesis

The rehabilitation programs of bone-anchorage prostheses relying either on the OPRA (Integrum, Sweden) or the ILP (Orthodynamics, Germany) fixation involve some forms of static load bearing exercises (LBE). So far, most of biomechanical studies of these static LBEs focused on the direct measurements of the actual forces and moments applied on the OPRA fixation of individuals with transfemoral amputation (TFA). To date, the proof-of-concept of an apparatus to conduct these kinetic measurements has been presented, along with some preliminary data. The understanding of the kinetic data is essential to improve rehabilitation programs as well as the design of upcoming loading frames. However, kinetic information alone is difficult to interpret without concomitant kinematic data. The purpose of this preliminary study was to introduce a qualitative analysis describing the different body postures during LBE for a group of TFAs.

Load applied on a bone-anchored transfemoral prosthesis: characterisation of a prosthesis : a pilot study

The objectives of this study were (A) to record the inner prosthesis loading during activities of daily living (ADL), (B) to present a set of variables comparing loading data, and (C) to provide an example of characterisation of two prostheses. The load was measured at 200 Hz using a multi-axial transducer mounted between the residuum and the knee of an individual with unilateral transfemoral amputation fitted with a bone-anchored prosthesis. The load was measured while using two different prostheses including a mechanically (PRO1) and a microprocessor controlled (PRO2) knee during six ADL. The characterisation of prosthesis was achieved using a set of variables split into four categories, including temporal characteristics, maximum loading, loading slopes and impulse. Approximately 360 gait cycles were analysed for each prosthesis. PRO1 showed a cadence improved by 19% and 7%, a maximum force on the long axis reduced by 11% and 19%, as well as an impulse reduced by 32% and 15% during descent of incline and stairs compared to PRO2, respectively. This work confirmed that the proposed apparatus and characterisation can reveal how changes of prosthetic components are translated into inner loading.

Rehabilitation of individuals with bone-anchored prosthesis: State-of-the-art and challenges

Individuals with limb amputation fitted with conventional socket-suspended prostheses often experience socket-related discomfort leading to a significant decrease in quality of life. Bone-anchored prostheses are increasingly acknowledged as viable alternative method of attachment of artificial limb. In this case, the prosthesis is attached directly to the residual skeleton through a percutaneous fixation. To date, a few osseointegration fixations are commercially available. Several devices are at different stages of development particularly in Europe and the US.[1-15] Clearly, surgical procedures are currently blooming worldwide. Indeed, Australia and Queensland in particular have one of the fastest growing populations. Previous studies involving either screw-type implants or press-fit fixations for bone-anchorage have focused on fragmented biomechanics aspects as well as the clinical benefits and safety of the procedure. However, very few publications have synthetized this information and provided an overview of the current developments in bone-anchored prostheses worldwide, let alone in Australia. The purposes of the presentation will be: 1. To provide an overview of the state-of-art developments in bone-anchored prostheses with as strong emphasis on the design of fixations, treatment, benefits, risks as well as future opportunities and challenges, 2. To present the current international developments of procedures for bone-anchored prostheses in terms of numbers of centers, number of cases and typical case-mix, 3. To highlight the current role Australia is playing as a leader worldwide in terms of growing population, broadest range of case-mix, choices of fixations, development of reimbursement schemes, unique clinical outcome registry for evidence-based practice, cutting-edge research, consumer demand and general public interest.

Cost-effectiveness of bone-anchored prosthesis: the Queensland experience

Individuals with limb amputation fitted with conventional socket-suspended prostheses often experience socket-related discomfort leading to a significant decrease in quality of life. Bone-anchored prostheses are increasingly acknowledged as viable alternative method of attachment of artificial limb. In this case, the prosthesis is attached directly to the residual skeleton through a percutaneous fixation. To date, a few osseointegration fixations are commercially available. Several devices are at different stages of development particularly in Europe and the US. [1-15] Clearly, surgical procedures are currently blooming worldwide. Indeed, Australia and Queensland, in particular, have one of the fastest growing populations. Previous studies involving either screw-type implants or press-fit fixations for bone-anchorage have focused on biomechanics aspects as well as the clinical benefits and safety of the procedure. In principle, bone-anchored prostheses should eliminate lifetime expenses associated with sockets and, consequently, potentially alleviate the financial burden of amputation for governmental organizations. Unfortunately, publications focusing on cost-effectiveness are sparse. In fact, only one study published by Haggstrom et al (2012), reported that “despite significantly fewer visits for prosthetic service the annual mean costs for osseointegrated prostheses were comparable with socket-suspended prostheses”. Consequently, governmental organizations such as Queensland Artificial Limb Services (QALS) are facing a number of challenges while adjusting financial assistance schemes that should be fair and equitable to their clients fitted with bone-anchored prostheses. Clearly, more scientific evidence extracted from governmental databases is needed to further consolidate the analyses of financial burden associated with both methods of attachment (i.e., conventional sockets prostheses, bone-anchored prostheses). The purpose of the presentation will be to share the current outcomes of a cost-analysis study lead by QALS. The specific objectives will be: • To outline methodological avenues to assess the cost-effectiveness of bone-anchored prostheses compared to conventional sockets prostheses, • To highlight the potential obstacles and limitations in cost-effectiveness analyses of bone-anchored prostheses, • To present cohort results of a cost-effectiveness (QALY vs cost) including the determination of fair Incremental cost-effectiveness Ratios (ICER) as well as cost-benefit analysis focusing on the comparing costs and key outcome indicators (e.g., QTFA, TUG, 6MWT, activities of daily living) over QALS funding cycles for both methods of attachment.

Cost effectiveness of osseointegration

Individuals with limb amputation fitted with conventional socket-suspended prostheses often experience socket-related discomfort leading to a significant decrease in quality of life. Bone-anchored prostheses are increasingly acknowledged as viable alternative method of attachment of artificial limb. In this case, the prosthesis is attached directly to the residual skeleton through a percutaneous fixation. To date, a few osseointegration fixations are commercially available. Several devices are at different stages of development particularly in Europe and the US. [1-15] Clearly, surgical procedures are currently blooming worldwide. Indeed, Australia and Queensland, in particular, have one of the fastest growing populations. Previous studies involving either screw-type implants or press-fit fixations for bone-anchorage have focused on biomechanics aspects as well as the clinical benefits and safety of the procedure. [16-25] In principle, bone-anchored prostheses should eliminate lifetime expenses associated with sockets and, consequently, potentially alleviate the financial burden of amputation for governmental organizations. Sadly, publications focusing on cost-effectiveness are sparse. In fact, only one study published by Haggstrom et al (2012), reported that “despite significantly fewer visits for prosthetic service the annual mean costs for osseointegrated prostheses were comparable with socket-suspended prostheses”.[26] Consequently, governmental organizations such as Queensland Artificial Limb Services (QALS) are facing a number of challenges while adjusting financial assistance schemes that should be fair and equitable to their clients fitted with bone-anchored prostheses. Clearly, more scientific evidence extracted from governmental databases is needed to further consolidate the analyses of financial burden associated with both methods of attachment (i.e., conventional sockets prostheses, bone-anchored prostheses). The purposes of the presentation will be: 1. To outline methodological avenues to assess the cost-effectiveness of bone-anchored prostheses compared to conventional sockets prostheses, 2. To highlight the potential obstacles and limitations in cost-effectiveness analyses of bone-anchored prostheses, 3. To present preliminary results of a cost-comparison analysis focusing on the comparison of the costs expressed in dollars over QALS funding cycles for both methods of attachment.

Osseointegration internationally: Australia is playing a key role?

Individuals with limb amputation fitted with conventional socket-suspended prostheses often experience socket-related discomfort leading to a significant decrease in quality of life. Bone-anchored prostheses are increasingly acknowledged as viable alternative method of attachment of artificial limb. In this case, the prosthesis is attached directly to the residual skeleton through a percutaneous fixation. To date, a few osseointegration fixations are commercially available. Several devices are at different stages of development particularly in Europe and the US.[1-15] Clearly, surgical procedures are currently blooming worldwide. Indeed, Australia and Queensland in particular have one of the fastest growing populations. Previous studies involving either screw-type implants or press-fit fixations for bone-anchorage have focused on fragmented biomechanics aspects as well as the clinical benefits and safety of the procedure. [16-25] However, very few publications have synthetized this information and provided an overview of the current developments in bone-anchored prostheses worldwide, let alone in Australia. The purposes of the presentation will be: 1. To provide an overview of the state-of-art developments in bone-anchored prostheses with as strong emphasis on the design of fixations, treatment, benefits, risks as well as future opportunities and challenges, 2. To present the current international developments of procedures for bone-anchored prostheses in terms of numbers of centers, number of cases and typical case-mix, 3. To highlight the current role Australia is playing as a leader worldwide in terms of growing population, broadest range of case-mix, choices of fixations, development of reimbursement schemes, unique clinical outcome registry for evidence-based practice, cutting-edge research, consumer demand and general public interest.

Static load bearing exercises of individuals with transfemoral amputation fitted with an osseointegrated implant: Reliability of kinetic data

This study aimed at presenting the intra-tester reliability of the static load bearing exercises (LBEs) performed by individuals with transfemoral amputation (TFA) fitted with an osseointegrated implant to stimulate the bone remodelling process. There is a need for a better understanding of the implementation of these exercises particularly the reliability. The intra-tester reliability is discussed with a particular emphasis on inter-load prescribed, inter-axis and inter-component reliabilities as well as the effect of body weight normalisation. Eleven unilateral TFAs fitted with an OPRA implant performed five trials in four loading conditions. The forces and moments on the three axes of the implant were measured directly with an instrumented pylon including a six-channel transducer. Reliability of loading variables was assessed using intraclass correlation coefficients (ICCs) and percentage standard error of measurement values (%SEMs). The ICCs of all variables were above 0.9 and the %SEM values ranged between 0 and 87%. This study showed a high between-participants’ variance highlighting the lack of loading consistency typical of symptomatic population as well as a high reliability between the loading sessions indicating a plausible correct repetition of the LBE by the participants. However, these outcomes must be understood within the framework of the proposed experimental protocol.

Human mesenchymal stem cell response to 444 ferritic stainless steel networks

The aim of this work is to improve bone-implant bonding. This can, potentially, be achieved through the use of an implant coating composed of fibre networks. It is hypothesised that such an implant can achieve strong peri-prosthetic bone anchorage, when seeded with human mesenchymal stem cells (hMSCs). The materials employed were 444 and 316L stainless steel fibre networks of the same fibre volume fraction. The present work confirms that hMSCs are able to proliferate and differentiate towards the osteogenic lineage when seeded onto the fibre networks. Cellular viability, proliferation and metabolic activity were assessed and the results suggest higher proliferation rates when hMSC are seeded onto the 444 networks as compared to 316L. Cell distribution was found uniform across the seeded surfaces with 444 showing a somewhat higher infiltration depth. Copyright © Materials Research Society 2013.

Mini-implant and Nance button for initial retraction of maxillary canines: a prospective study in cast models

OBJETIVO: a ancoragem óssea é fundamental para o sucesso do tratamento de algumas más oclusões, pois permite a aplicação de forças contínuas, diminui o tempo de tratamento e independe da colaboração do paciente. MÉTODOS: o propósito desse trabalho foi comparar, por meio de modelos dentários, a perda de ancoragem após a retração inicial de caninos superiores entre dois grupos. O grupo A utilizou o mini-implante enquanto o grupo B utilizou o Botão de Nance. Para todos os pacientes foram realizados dois modelos (M1 e M2). Os primeiros modelos foram realizados ao início (M1), e os outros ao final da retração inicial de canino (M2). RESULTADOS: todas as medidas foram tabuladas e submetidas à análise estatística. Para verificar o erro sistemático intraexaminador foi utilizado o teste t pareado. Na determinação do erro casual utilizou-se o cálculo de erro proposto por Dahlberg. Para comparação entre as fases Início e Após, foi utilizado o teste t pareado. Para a comparação entre os grupos de mini-implante e Botão de Nance, foi utilizado o teste t de Student para medidas independentes. em todos os testes foi adotado nível de significância de 5% (p<0,05). CONCLUSÃO: ao se medir e comparar em modelos dentários a perda de ancoragem dos molares após a retração inicial de canino utilizando-se dois sistemas de ancoragem distintos (Mini-implante e Botão de Nance), pôde-se observar a inexistência de diferença estatisticamente significativa entre os dois grupos.

Minimalinvasive Osteosynthese der distalen extraartikulären Radiusfraktur : XSCREW und DorsalNailPlate im biomechanischen Vergleich

Gegenstand der Arbeit: Die distale Radiusfraktur ist der häufigste Bruch des Menschen. Neben etablierten Verfahren wie der dorsalen und palmaren Plattenosteosynthese gibt es seit Kurzem neuartige minimalinvasive Osteosynthesesysteme. Gegenstand der vorliegenden Arbeit ist die Untersuchung der biomechanischen Stabilität von zwei neuartigen Implantaten für die distale extraartikuläre Radiusfraktur. rnMethodik: Es handelt sich einerseits um das System XSCREW (Zimmer, Freiburg i. Br., Deutschland), eine kanülierte Schraube, die über den Processus styloideus eingeführt wird und mit bis zu neun Bohrdrähten im Knochen fixiert werden kann. Das Vergleichsimplantat DorsalNailPlate (HandInnovations, Miami, Florida, USA) ist ein Hybrid aus einer dorsalen Platte und einem Marknagel. Beide Systeme wurden an 8 paarigen frischen unfixierten Leichenradii unter Axialbelastung bis 100 N und Torsionsbelastung bis 1,5 Nm getestet. Die A3-Fraktur wurde durch eine standardisierte Keilosteotomie simuliert. Das Biomaterial wurde prä- und postinterventionell sowie nach einem Dauerbelastungstest unter 1000 Zyklen in Rotation mit 0,5 Hz untersucht. Ein Versagenstest mit steigendem Drehmoment beendete das Experiment. rnErgebnisse: Die XSCREW erreichte eine Axialsteifigkeit von 136 N/mm und eine Torsionssteifigkeit von 0,16 Nm/°. Die DNP erzielte hingegen axial 70 N/mm und torsional 0,06 Nm/°. Der Unterschied zwischen beiden Verfahren war nur für die Torsion eindeutig statistisch auffällig (p=0,012), jedoch nicht für die Axialsteifigkeit (p=0,054). Die ursprüngliche Axial- und Torsionssteifigkeit wurde durch die XSCREW signifikant besser wiederhergestellt als durch die DNP (p=0,012). Beide Verfahren erzielten nach der Intervention signifikant niedrigere Steifigkeiten als die intakten Knochen (p=0,012). Ein Präparat der DNP-Gruppe und vier Präparate der XSCREW-Gruppe überstanden den Dauerbelastungstest. Das Drehmoment bei Versagen war mit der XSCREW höher als mit der DNP, der Unterschied zwischen den Verfahren war signifikant (p=0,043). Die Schwachstellen beider Systeme lagen vorwiegend in der proximalen Verankerung im Knochen. Kirschner-Drähte bzw. Verriegelungsschrauben führten unter andauernder Belastung zu einer Spaltung der Kortikalis im Schaftbereich. Bedingt durch die Ausrichtung der distalen Verriegelungen können mit beiden Implantaten Schäden an der radiocarpalen bzw. radioulnaren Gelenkfläche entstehen. rnZusammenfassung: Die XSCREW ermöglicht insgesamt eine höhere mechanische Stabilität als die DNP. Beide Verfahren sind jedoch einer winkelstabilen palmaren Plattenosteosynthese insbesondere unter rotatorischer Dauerbelastung unterlegen und erreichen nicht die Stabilität eines anderen neuartigen minimalinvasiven Systems.

Biomechanical evaluation of the interfacial strength of a chemically modified sandblasted and acid-etched titanium surface

The functional capacity of osseointegrated dental implants to bear load is largely dependent on the quality of the interface between the bone and implant. Sandblasted and acid-etched (SLA) surfaces have been previously shown to enhance bone apposition. In this study, the SLA has been compared with a chemically modified SLA (modSLA) surface. The increased wettability of the modSLA surface in a protein solution was verified by dynamic contact angle analysis. Using a well-established animal model with a split-mouth experimental design, implant removal torque testing was performed to determine the biomechanical properties of the bone-implant interface. All implants had an identical cylindrical shape with a standard thread configuration. Removal torque testing was performed after 2, 4, and 8 weeks of bone healing (n = 9 animals per healing period, three implants per surface type per animal) to evaluate the interfacial shear strength of each surface type. Results showed that the modSLA surface was more effective in enhancing the interfacial shear strength of implants in comparison with the conventional SLA surface during early stages of bone healing. Removal torque values of the modSLA-surfaced implants were 8-21% higher than those of the SLA implants (p = 0.003). The mean removal torque values for the modSLA implants were 1.485 N m at 2 weeks, 1.709 N m at 4 weeks, and 1.345 N m at 8 weeks; and correspondingly, 1.231 N m, 1.585 N m, and 1.143 N m for the SLA implants. The bone-implant interfacial stiffness calculated from the torque-rotation curve was on average 9-14% higher for the modSLA implants when compared with the SLA implants (p = 0.038). It can be concluded that the modSLA surface achieves a better bone anchorage during early stages of bone healing than the SLA surface; chemical modification of the standard SLA surface likely enhances bone apposition and this has a beneficial effect on the interfacial shear strength.

PÊNDULO ANCORADO EM MINI-IMPLANTES - ANÁLISE EM MODELOS DIGITAIS

A distalização dos molares superiores é uma opção de tratamento da má oclusão de Classe II, quando o envolvimento é principalmente dentoalveolar. Dispositivos intrabucais como o aparelho Pêndulo, dispensam a colaboração do paciente quanto ao uso, porém promovem efeitos muitas vezes indesejáveis como a vestibularização dos dentes anteriores que participam na ancoragem e a inclinação dos molares distalizados. Após o surgimento dos Dispositivos de Ancoragem Temporária (DATs), como o mini-implante pode-se alcançar a ancoragem de forma previsível e eficiente. Com isto, por meio de um estudo prospectivo, foram avaliadas as alterações dentárias, promovidas pela distalização de molares superiores com um aparelho Pêndulo modificado, apoiado em dois mini-implantes instalados no palato de 10 indivíduos, sendo 2 do sexo feminino e 8 do masculino, com média de idade de 14,3 anos. A amostra foi composta por 20 modelos digitalizados em 3D, obtidos de em duas fases: no início do tratamento (T1) e após distalização com sobrecorreção de 1 mm (T2), permitindo quantificar as alterações dentárias sagitais, transversais e possíveis movimentos de rotação, angulação e movimentos verticais. Os resultados obtidos mostraram que no sentido sagital, houve uma efetiva distalização com significância estatística, para os segundos molares superiores; primeiros molares superiores em média de 4,34 mm e 3,91mm para o lado direito e esquerdo, respectivamente, e para os segundos pré-molares do lado direito e esquerdo de 2,06 mm e 1,95 mm, respectivamente. Porém, para os dentes anteriores, foi constatada a perda de ancoragem. No sentido transversal, o maior aumento ocorreu na região dos dentes posteriores. Os movimentos de rotação, angulação e vertical dos primeiros molares superiores, indicam que houve rotação mesiovestibular e inclinação distal das coroas destes dentes de ambos os lados; as medidas verticais, demonstram que houve movimento significativo apenas para o primeiro molar direito, com inclinação distal pela intrusão da cúspide distal. Este dispositivo mostrou-se eficaz na correção da Classe II em um tempo médio de 6,2 meses.(AU)

PÊNDULO ANCORADO EM MINI-IMPLANTES - ANÁLISE EM MODELOS DIGITAIS

A distalização dos molares superiores é uma opção de tratamento da má oclusão de Classe II, quando o envolvimento é principalmente dentoalveolar. Dispositivos intrabucais como o aparelho Pêndulo, dispensam a colaboração do paciente quanto ao uso, porém promovem efeitos muitas vezes indesejáveis como a vestibularização dos dentes anteriores que participam na ancoragem e a inclinação dos molares distalizados. Após o surgimento dos Dispositivos de Ancoragem Temporária (DATs), como o mini-implante pode-se alcançar a ancoragem de forma previsível e eficiente. Com isto, por meio de um estudo prospectivo, foram avaliadas as alterações dentárias, promovidas pela distalização de molares superiores com um aparelho Pêndulo modificado, apoiado em dois mini-implantes instalados no palato de 10 indivíduos, sendo 2 do sexo feminino e 8 do masculino, com média de idade de 14,3 anos. A amostra foi composta por 20 modelos digitalizados em 3D, obtidos de em duas fases: no início do tratamento (T1) e após distalização com sobrecorreção de 1 mm (T2), permitindo quantificar as alterações dentárias sagitais, transversais e possíveis movimentos de rotação, angulação e movimentos verticais. Os resultados obtidos mostraram que no sentido sagital, houve uma efetiva distalização com significância estatística, para os segundos molares superiores; primeiros molares superiores em média de 4,34 mm e 3,91mm para o lado direito e esquerdo, respectivamente, e para os segundos pré-molares do lado direito e esquerdo de 2,06 mm e 1,95 mm, respectivamente. Porém, para os dentes anteriores, foi constatada a perda de ancoragem. No sentido transversal, o maior aumento ocorreu na região dos dentes posteriores. Os movimentos de rotação, angulação e vertical dos primeiros molares superiores, indicam que houve rotação mesiovestibular e inclinação distal das coroas destes dentes de ambos os lados; as medidas verticais, demonstram que houve movimento significativo apenas para o primeiro molar direito, com inclinação distal pela intrusão da cúspide distal. Este dispositivo mostrou-se eficaz na correção da Classe II em um tempo médio de 6,2 meses.(AU)

PÊNDULO ANCORADO EM MINI-IMPLANTES - ANÁLISE EM MODELOS DIGITAIS

A distalização dos molares superiores é uma opção de tratamento da má oclusão de Classe II, quando o envolvimento é principalmente dentoalveolar. Dispositivos intrabucais como o aparelho Pêndulo, dispensam a colaboração do paciente quanto ao uso, porém promovem efeitos muitas vezes indesejáveis como a vestibularização dos dentes anteriores que participam na ancoragem e a inclinação dos molares distalizados. Após o surgimento dos Dispositivos de Ancoragem Temporária (DATs), como o mini-implante pode-se alcançar a ancoragem de forma previsível e eficiente. Com isto, por meio de um estudo prospectivo, foram avaliadas as alterações dentárias, promovidas pela distalização de molares superiores com um aparelho Pêndulo modificado, apoiado em dois mini-implantes instalados no palato de 10 indivíduos, sendo 2 do sexo feminino e 8 do masculino, com média de idade de 14,3 anos. A amostra foi composta por 20 modelos digitalizados em 3D, obtidos de em duas fases: no início do tratamento (T1) e após distalização com sobrecorreção de 1 mm (T2), permitindo quantificar as alterações dentárias sagitais, transversais e possíveis movimentos de rotação, angulação e movimentos verticais. Os resultados obtidos mostraram que no sentido sagital, houve uma efetiva distalização com significância estatística, para os segundos molares superiores; primeiros molares superiores em média de 4,34 mm e 3,91mm para o lado direito e esquerdo, respectivamente, e para os segundos pré-molares do lado direito e esquerdo de 2,06 mm e 1,95 mm, respectivamente. Porém, para os dentes anteriores, foi constatada a perda de ancoragem. No sentido transversal, o maior aumento ocorreu na região dos dentes posteriores. Os movimentos de rotação, angulação e vertical dos primeiros molares superiores, indicam que houve rotação mesiovestibular e inclinação distal das coroas destes dentes de ambos os lados; as medidas verticais, demonstram que houve movimento significativo apenas para o primeiro molar direito, com inclinação distal pela intrusão da cúspide distal. Este dispositivo mostrou-se eficaz na correção da Classe II em um tempo médio de 6,2 meses.(AU)

Ancoragem na movimentação ortodôntica

Uma ancoragem eficiente é um factor de extrema importância em Ortodontia. Perante a relevância deste assunto e sendo ainda um desafio para muitos ortodontistas, este trabalho tem como objetivo realizar uma revisão bibliográfica sobre dispositivos de ancoragem, especificamente mini-implantes e mini-placas, entendendo que os mesmos surgiram como auxiliares importantes no tratamento ortodôntico, com a finalidade de relacionar os tipos, indicações, aplicações clínicas, locais de instalação, vantagens, possíveis complicações na sua utilização e cuidados a serem tomados. Alta versatilidade de aplicação clínica, eliminação de movimentos indesejáveis dos dentes pilares, movimentos precisos, movimentos mais rápidos, redução de custos, processo cirúrgico simples e pouco invasivo, substituição de aparelhos extraorais, tamanho reduzido e capacidade de suportar de imediato forças ortodônticas pesadas, são algumas das vantagens na utilização dos mini-implantes e mini-placas que fazem com que a ancoragem óssea absoluta obtida através do seu uso crie melhores condições na obtenção dos objetivos propostos no tratamento ortodôntico com aparatologia fixa.