Treatment effects of the MARA appliance and Activator-Headgear combined with fixed appliances in Class II division 1 malocclusion patients: A retrospective longitudinal study

ABSTRACT Introduction: Class II division 1 malocclusion treatment with functional devices offers acceptable results. These devices can be removable or fixed, and the essential difference between them is the need for compliance. It is clinically important to investigate if there are differences in the treatment effects of these devices that present different characteristics. Objective: This retrospective longitudinal study compared the treatment effects of Class II correction with the MARA appliance, Activator-Headgear (AcHg) combination, both followed by multibracket fixed appliances, and an untreated control group. Material and Methods: Each experimental group was composed of 18 patients, with a baseline mean age of 11.70 and 10.88 years, treated for 3.60 and 3.17 years. The control group consisted of 20 subjects with baseline mean age of 11.07 years. The groups were evaluated before (T1) and after (T2) treatment. Lateral radiographs were used to evaluate the treatment changes with treatment (T2-T1), compared to the control group. Intergroup comparisons were performed using repeated-measures analysis of variance (ANOVA), followed by Tukey's test. Results: The AcHg group showed significantly greater maxillary growth restriction than the MARA, while the mandibular changes were due to natural growth. Both devices promoted significantly greater maxillary incisors retrusion, mandibular incisors labial inclination, and improvement of overjet and molar relationships, compared to the control. Conclusions: Both functional devices followed by multibracket appliances were effective to correct Class II malocclusion. Nonetheless, the AcHg combination presents superior skeletal effects, due to significantly greater maxillary growth restriction compared to the MARA appliance. Moreover, the appliances presented similar dentoalveolar effects.

RESUMO Introdução: O tratamento da má oclusão de Classe II divisão 1 com dispositivos funcionais oferece resultados aceitáveis. Esses dispositivos podem ser removíveis ou fixos, e a diferença essencial entre eles é a necessidade de colaboração. É clinicamente importante investigar se existem diferenças nos efeitos do tratamento desses dispositivos que apresentam características diferentes. Objetivo: O presente estudo retrospectivo longitudinal comparou os efeitos do MARA e da combinação Aparelho Extrabucal-Ativador (AEB-At) no tratamento da Classe II, ambos seguidos por aparelho fixo, adicionando também um grupo controle não tratado. Métodos: Cada grupo experimental foi composto por 18 pacientes; respectivamente, com média de idade inicial de 11,70 e 10,88 anos, tratados por 3,60 e 3,17 anos. O grupo controle foi composto por 20 indivíduos, com idade média inicial de 11,07 anos. Os grupos foram avaliados antes (T1) e após (T2) o tratamento. Radiografias de perfil foram utilizadas para avaliar as alterações do tratamento (T2-T1), em comparação com o grupo controle. As comparações intergrupos foram realizadas por meio da análise de variância para medidas repetidas (ANOVA), seguida pelo teste de Tukey. Resultados: O AEB-At apresentou uma restrição do crescimento maxilar significativamente maior que o MARA, enquanto as alterações mandibulares foram decorrentes do crescimento natural. Ambos os dispositivos promoveram significativamente mais retrusão dos incisivos superiores, inclinação vestibular dos incisivos inferiores e melhora da sobressaliência e relação molar, em comparação com o controle. Conclusões: Ambos os dispositivos funcionais associados ao aparelho fixo foram efetivos na correção da má oclusão de Classe II. No entanto, a combinação AEB-At apresenta efeitos esqueléticos superiores, devido à restrição de crescimento maxilar significativamente maior do que com o aparelho MARA. Além disso, os aparelhos apresentaram efeitos dentoalveolares semelhantes.

Comparison of treatment effects between the modified C-palatal plate and cervical pull headgear for total arch distalization in adults / 대한치과교정학회지

OBJECTIVE: The purpose of this study was to evaluate the dental and skeletal effects of the modified C-palatal plate (MCPP) for total arch distalization in adult patients with Class II malocclusion and compare the findings with those of cervical pull headgear. METHODS: The study sample consisted of the lateral cephalograms of 44 adult patients with Class II Division 1 malocclusion, including 22 who received treatment with MCPP (age, 24.7 ± 7.7 years) and 22 who received treatment with cervical pull headgear (age, 23.0 ± 7.7 years). Pre- (T1) and post-treatment (T2) cephalograms were analyzed for 24 linear and angular measurements. Multivariate analysis of variance was performed to evaluate the changes after treatment in each group and differences in treatment effects between the two groups. RESULTS: The mean amount of distalization at the crown and root levels of the maxillary first molar and the amount of distal tipping was 4.2 mm, 3.5 mm, and 3.9° in the MCPP group, and 2.3 mm, 0.6 mm, and 8.6° in the headgear group, respectively. In addition, intrusion by 2.5 mm was observed in the MCPP group. In both groups, the distal movement of the upper lip and the increase in the nasolabial angle were statistically significant (p < 0.001). However, none of the skeletal and soft tissue variables exhibited significant differences between the two groups. CONCLUSIONS: The results of this study suggest that MCPP is an effective treatment modality for total arch distalization in adults.

Class II, Division 1 Angle malocclusion with severe proclination of maxillary incisors

Protrusion of maxillary incisors is a common complaint among patients seeking orthodontic treatment. This report addresses the correction of Class II Angle malocclusion with excessively bucally proclined maxillary incisors, in an adolescent female patient, through the use of extraoral and fixed appliances. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as part of the requirements for obtaining the title of certified by the BBO.

A protrusão dos incisivos superiores é uma queixa frequente nos pacientes que buscam o tratamento ortodôntico. O presente relato aborda a correção de uma má oclusão de Classe II de Angle, com severa protrusão e inclinação para vestibular dos incisivos superiores, em uma paciente adolescente do sexo feminino, por meio do uso de aparelhagem extrabucal e fixa. Esse caso clínico foi apresentado à Diretoria do Board Brasileiro de Ortodontia e Ortopedia Facial (BBO), como parte dos requisitos para a obtenção do título de Diplomada pelo BBO.

A three-dimensional finite element analysis of molar distalization with a palatal plate, pendulum, and headgear according to molar eruption stage / 대한치과교정학회지

OBJECTIVE: This study aimed to (1) evaluate the effects of maxillary second and third molar eruption status on the distalization of first molars with a modified palatal anchorage plate (MPAP), and (2) compare the results to the outcomes of the use of a pendulum and that of a headgear using three-dimensional finite element analysis. METHODS: Three eruption stages were established: an erupting second molar at the cervical one-third of the first molar root (Stage 1), a fully erupted second molar (Stage 2), and an erupting third molar at the cervical one-third of the second molar root (Stage 3). Retraction forces were applied via three anchorage appliance models: an MPAP with bracket and archwire, a bone-anchored pendulum appliance, and cervical-pull headgear. RESULTS: An MPAP showed greater root movement of the first molar than crown movement, and this was more noticeable in Stages 2 and 3. With the other devices, the first molar showed distal tipping. Transversely, the first molar had mesial-out rotation with headgear and mesial-in rotation with the other devices. Vertically, the first molar was intruded with an MPAP, and extruded with the other appliances. CONCLUSIONS: The second molar eruption stage had an effect on molar distalization, but the third molar follicle had no effect. The application of an MPAP may be an effective treatment option for maxillary molar distalization.

Combined treatment with headgear and the Frog appliance for maxillary molar distalization: a randomized controlled trial / 대한치과교정학회지

OBJECTIVE: To evaluate the efficiency of the Frog appliance (FA) alone or in combination with headgear for distalizing the maxillary molars. METHODS: Fifty patients (25 males and 25 females) aged 12.6 - 16.7 years who received treatment for Class II malocclusion at the Orthodontic Clinic of Al-Baath University were selected for this study and randomly divided into 2 equal groups. Maxillary molar distalization was achieved using the FA alone (group 1) or a combination of the FA with high-pull headgear worn at night (group 2). Lateral cephalograms were obtained before and after treatment. RESULTS: The maxillary molars moved distally by 5.51 and 5.93 mm in groups 1 and 2, respectively. Distal movements were associated with axial tipping by 4.96degrees and 1.25degrees, and with loss of anchorage by mesial movement of the second maxillary premolars by 2.70 and 0.90 mm in groups 1 and 2, respectively. The combined use of the FA and nighttime high-pull headgear decreased the distalization time and improved the ratio of maxillary molar distalization movement relative to the overall opening space between the first maxillary molars and second premolars. CONCLUSIONS: The FA can effectively distalize the maxillary molars, this distalization associates with some unfavorable changes. Nighttime use of high-pull headgear combined with the FA can reduce these unfavorable changes and improve treatment outcomes.

Combined treatment with headgear and the Frog appliance for maxillary molar distalization: a randomized controlled trial / 대한치과교정학회지

OBJECTIVE: To evaluate the efficiency of the Frog appliance (FA) alone or in combination with headgear for distalizing the maxillary molars. METHODS: Fifty patients (25 males and 25 females) aged 12.6 - 16.7 years who received treatment for Class II malocclusion at the Orthodontic Clinic of Al-Baath University were selected for this study and randomly divided into 2 equal groups. Maxillary molar distalization was achieved using the FA alone (group 1) or a combination of the FA with high-pull headgear worn at night (group 2). Lateral cephalograms were obtained before and after treatment. RESULTS: The maxillary molars moved distally by 5.51 and 5.93 mm in groups 1 and 2, respectively. Distal movements were associated with axial tipping by 4.96degrees and 1.25degrees, and with loss of anchorage by mesial movement of the second maxillary premolars by 2.70 and 0.90 mm in groups 1 and 2, respectively. The combined use of the FA and nighttime high-pull headgear decreased the distalization time and improved the ratio of maxillary molar distalization movement relative to the overall opening space between the first maxillary molars and second premolars. CONCLUSIONS: The FA can effectively distalize the maxillary molars, this distalization associates with some unfavorable changes. Nighttime use of high-pull headgear combined with the FA can reduce these unfavorable changes and improve treatment outcomes.

A influência da má oclusão Classe II e do uso do aparelho extraoral no espaço aéreo nasofaríngeo / The influence of Class II malocclusion and the use of headgear appliance over nasopharyngeal airway space

A redução do espaço aéreo nasofaríngeo pode estar associada a vários fatores, em especial à hipertrofia das tonsilas. Estudos mais recentes, entretanto, apontam que este estreitamento também pode ser decorrente de más oclusões esqueléticas, em especial da Classe II. Objetivou-se com esta revisão de literatura estudar a influência desta displasia e o tratamento da mesma com aparelho extraoral, no tamanho do espaço aéreo nasofaríngeo.

Nasopharyngeal airway space reduction can be associated to various factors, especially to hypertrophic tonsils. Most recent studies, however, demonstrate that this constriction can also be related to skeletal malocclusions, most specifically, the Class II malocclusion. The purpose of this literature review was to report the influence of this skeletal dysplasia, and its treatment with headgear appliances, on the size of the nasopahryngeal airway.

Effects induced after the use of maxillary protraction appliances: a literature review / Efeitos induzidos após uso de aparelhos para tração reversa da maxila: uma revisão de literatura

OBJECTIVE: The present literature review, examined the effects of maxillary protraction in patients treated with different types of facial masks. METHODS: The review searched for relevant articles, including randomized controlled trials, controlled clinical trials and uncontrolled trials. Comparisons were made between eight different types of facial masks: Delaire; Grummons; Petit; Turley; Batista; "Sky Hook"; Nanda and Türbinger. Following aspects were evaluated: a) the type of anchorage; the origin, direction and magnitude of forces and b) the relevant results of following skeletal and dental measurements: angular (SNA and SNB), linear (AFAI); vertical angles (SN.GoGn, FMA); dental (IMPA) and linear (1-NA, 1-NB). CONCLUSION: The results showed that there was no uniformity in the choice of anchorage type and form of application of forces between the facial masks examined, but there were similarities in skeletal and dental aspects: Anterior displacement of the maxillary complex (increase in SNA) ; anterior displacement of the upper anterior teeth (increase of 1-NA), the lingual inclination of mandibular incisors (decrease of 1-NB), down and back rotation of the mandible (increase AFAI, SN.GoGn, FMA, decrease in SNB).

OBJETIVO: o presente trabalho de revisão de literatura consistiu em realizar um estudo comparativo entre diversos modelos de máscaras faciais em relação às suas influências dentárias e esqueléticas e suas implicações sobre a altura facial inferior. MÉTODOS: optou-se pela busca de artigos relevantes, abrangendo estudos randomizados controlados, ensaios clínicos controlados e não-controlados, incluídos de acordo com critérios de elegibilidade. Foi realizada a comparação entre oito diferentes modelos de máscaras faciais: Delaire, Grummons, Petit, Turley, Batista, Sky Hook, Nanda e Tübinger. Foram coletados: a) o tipo de ancoragem, a origem, direção e magnitude das forças entre as máscaras faciais; e b) os resultados pertinentes às alterações das grandezas esqueléticas SNA e SNB, AFAI - ENA-Me, SN.GoGn, FMA; e as grandezas dentárias IMPA, 1-NA e 1-NB. CONCLUSÃO: não houve uniformidade na escolha do tipo de ancoragem e forma da aplicação das forças entre as máscaras envolvidas no estudo. Houve semelhança nas grandezas esqueléticas e dentárias: deslocamento anterior do complexo maxilar (aumento do SNA), deslocamento anterior dos dentes superiores (aumento do 1-NA), inclinação lingual dos incisivos inferiores (diminuição do 1-NB e IMPA), rotação da mandíbula para baixo e para trás (aumento do AFAI, SN.GoGn e FMA, diminuição do SNB).

Orthopedic treatment of Class III malocclusion with rapid maxillary expansion combined with a face mask: a cephalometric assessment of craniofacial growth patterns

OBJECTIVE: The aim of this prospective study was to assess potential changes in the cephalometric craniofacial growth pattern of 17 children presenting Angle Class III malocclusion treated with a Haas-type expander combined with a face mask. METHODS: Lateral cephalometric radiographs were taken at beginning (T1) and immediately after removal of the appliances (T2), average of 11 months of treatment. Linear and angular measurements were used to evaluate the cranial base, dentoskeletal changes and facial growth pattern. RESULTS: The length of the anterior cranial base experienced a reduction while the posterior cranial base assumed a more vertical position at T1. Some maxillary movement occurred, there was no rotation of the palatal plane, there was a slight clockwise rotation of the mandible, although not significant. The ANB angle increased, thereby improving the relationship between the jaws; dentoalveolar compensation was more evident in the lower incisors. Five out of 12 cases (29.41%) showed the following changes: In one case the pattern became more horizontal and in four cases more vertical. CONCLUSIONS: It was concluded after a short-term assessment that treatment with rapid maxillary expansion (RME) associated with a face mask was effective in the correction of Class III malocclusion despite the changes in facial growth pattern observed in a few cases.

Desarrollo de un modelo FEM del complejo craneofacial para simular tratamientos en CLASE III esqueletica / Craniofacial FEM for skeletal CLASS III malocclusion treatments simulation

Introducción y Objetivo: En bioingeniería hay limitantes en la realización de experimentos sobrehumanos por lo que usa el método de elementos finitos. Describir el método de reconstrucción de un cráneo completo para desarrollar un modelo de elementos finitos para posteriormente simular la acción de diferentes dispositivos para el tratamiento del prognatismo mandibular.

Introducction and Objetive: In bioengineering, experiments on humans are limited. Given this,finite element method is needed. To describe the method of reconstruction of a skull to develop afinite element model that allows simulating the effect of different orthodontic devices for the treatmentof mandibular prognathism.

Análise do movimento inicial de molares superiores submetidos a forças extrabucais: estudo 3D / Analysis of initial movement of maxillary molars submitted to extraoral forces: a 3D study

OBJETIVO: analisar pelo método dos elementos finitos o deslocamento dos molares superiores frente a três diferentes inclinações do arco externo do aparelho extrabucal na tração do tipo cervical. MÉTODOS: maxila, dentes montados em má oclusão de Classe II e aparelho foram modelados através de formulação variacional e seus valores reproduzidos em coordenadas X, Y e Z. Foram realizadas simulações em microcomputador tipo PC, utilizando o programa ANSYS versão 8.1. Cada modelo de arco externo reproduziu linhas de força que passaram (1) acima (AcCR), (2) abaixo (AbCR) e (3) no centro de resistência (CR) do molar permanente superior de um mesmo modelo portador de má oclusão de Classe II. A avaliação restringiu-se ao movimento inicial dos molares frente à força extrabucal de 4 Newtons. RESULTADOS: o movimento distal inicial dos molares, tendo como ponto de referência a mesial do tubo, foi maior na coroa do modelo AbCR (0,47x10-6), e maior na raiz do modelo AcCR (0,32x10-6), provocando inclinações da coroa para distal e mesial, respectivamente. No modelo CR, os pontos na coroa (0,15x10-6) e raiz (0,12x10-6) deslocaram-se para distal equilibradamente, resultando em movimento de translação. Em todos os modelos, numa vista oclusal, houve tendência de rotação distal inicial da coroa, porém no modelo CR esse movimento foi muito pequeno. No sentido vertical (Z), todos os modelos revelaram movimento extrusivo (AbCR= 0,18x10-6; CR= 0,62x10-6; AcCR= 0,72x10-6). CONCLUSÃO: a simulação computacional do uso de aparelho extrabucal com tração cervical revelou a ocorrência de movimento extrusivo e distal, podendo ser por inclinação distal de coroa, de raiz ou movimento de translação.

OBJECTIVE: To analyze maxillary molar displacement by applying three different angulations to the outer bow of cervical-pull headgear, using the finite element method (FEM). METHODS: Maxilla, teeth set up in Class II malocclusion and equipment were modeled through variational formulation and their values represented in X, Y, Z coordinates. Simulations were performed using a PC computer and ANSYS software version 8.1. Each outer bow model reproduced force lines that ran above (ACR) (1), below (BCR) (2) and through the center of resistance (CR) (3) of the maxillary permanent molars of each Class II model. Evaluation was limited to the initial movement of molars submitted to an extraoral force of 4 Newtons. RESULTS: The initial distal movement of the molars, using as reference the mesial surface of the tube, was higher in the crown of the BCR model (0.47x10-6) as well as in the root of the ACR (0.32x10-6) model, causing the crown to tip distally and mesially, respectively. On the CR model, the points on the crown (0.15 x10-6) and root (0.12 x10-6) moved distally in a balanced manner, which resulted in bodily movement. In occlusal view, the crowns on all models showed a tendency towards initial distal rotation, but on the CR model this movement was very small. In the vertical direction (Z), all models displayed extrusive movement (BCR 0.18 x10-6; CR 0.62 x10-6; ACR 0.72x10-6). CONCLUSIONS: Computer simulations of cervical-pull headgear use disclosed the presence of extrusive and distal movement, distal crown and root tipping, or bodily movement.

Maloclusión Clase III: corrección con distalización superior e inferior / Class III malocclusion: correction with superior and inferior distalization

El tratamiento de las maloclusiones clase III incluye diferentes alternativas desde las terapias ortopédicas en edades tempranas, compensaciones dentales con ortodoncia o tratamiento ortodóncico-quirúrgico. La distalización de molares ha sido ampliamente utilizada en el arco superior para la corrección de maloclusiones clase II y el apiñamiento dental superior, y un poco menos en el arco inferior para ayudar a la corrección de leves apiñamientos y las clases III. Este reporte de caso muestra la corrección de la maloclusion clase III con el uso de la tracción cervical mandibular desde edad temprana para lograr un efecto ortopédico y distalizar molares inferiores evitando extracciones dentales, y el uso de un péndulo óseo soportado para distalizar molares superiores y corregir la discrepancia dentoalveolar. La terapia de combinación ortopédica-ortodóncica tuvo una duración de 40 meses y el uso de la distalización dental bimaxilar probó ser un método efectivo para la corrección de la clase III esquelético dental sin extracciones, con un buen resultado en la estética facial.

The treatment of Class III malocclusion includes different alternatives ranging from orthopedic therapy at early ages, orthodontic dental compensations or orthodontic-surgical treatment. Molar distalization has been widely used in the upper arch for the correction of Class II malocclusion and dental crowding; it has not been used as much in the lower arch where it is used to correct moderate crowding and Class III malocclusion. This case report shows the correction of a Class III malocclusion by means of the use of mandibular cervical headgear from an early age in order to obtain an orthopedic effect and distalization of lower molars, avoiding teeth extractions; a bone supported pendulum was usedin the upper arch to distalize molar and to correct the dentoalveolar discrepancy. The orthodontic orthopedic combined therapy lasted 40 months and the bi-maxillary dental distalization proved to be an effective method for the correction of skeletal dental Class III malocclusion, obtaining a good esthetic result.

Clinical effect of orthopedic-orthodontic treatment in crossbite in deciduous dentition / 中华医学美学美容杂志

Objective To study the clinical effect of orthopedic-orthodontic treatment in crossbite in deciduous dentition through cephalmetric analysis. Methods 12 children with crossbite in deciduous dentition were enrolled in treatment group. Control group included 8 patients with normal deciduous dentition. Modified reverse headgear was used in each patient in the treatment group. Orthodontic force was a-bout 2. 94-4. 90 N (300-500 g) , and the direction of force was under occlusion plane for 37 degree. Each patient wore reverse headgear for 10 hour per day. Orthodontic treatment lasted for 6 months, and then orthodontic treatment began at once. Orthodontic treatment was not over until crossbite was corrected. The cephalmetric change was compared between two groups before treatment (T1) , after orthopedic treatment (T2)and after orthodontic treatment (T3). The effect of orthopedic-orthodontic treatment was analyzed in two group. Results Crossbite was corrected successfully in all patients in the treatment group. After treatment, A point moved forward by 2. 8mm, Is-FHp increased 8. 38 mm, ＜SNA increased 2. 65, incisors in mandible moved backward a little bit. All these changes were statistical different as compared with those in the control group. Conclusion Skeletal and dental deformity are improved progressively after combined orthopedic-orthodontic treatment. It is recommended to perform orthopedic-orthodontic therapy in skeletal crossbite in deciduous dentition.

Mandibular behavior in the treatment of skeletal class II malocclusion: a 5-year post-retention analysis

Aim: This study aimed to assess mandibular behavior in Class II subjects subjected to full orthodontic treatment with standard edgewise appliance and cervical headgear (Kloehn appliance) during the pubertal growth spurt period. Methods: Lateral cephalometric radiographs of 40 patients (21 females and 19 males) were performed at the beginning of the treatment (T0), at its end (T1) and at 5-year post-retention phase (T2) in order to quantify the cephalometric measurements (8 angular and 3 linear), representing the mandibular behavior in the anteroposterior and vertical senses. The mean age of female patients at T0, T1 and T2 was 11.4, 15 and 26 years, respectively, and for male patients it was 12.2, 16.7 and 28 years, respectively. All patients were treated in just one phase without extractions and not associating Class II intermaxillary elastics. Results: The effective treatment of skeletal Class II malocclusion with conventional Edgewise fixed appliance and Kloehn cervical headgear did not interfere in the direction and amount of mandibular growth as well as remodeling at it is inferior border, with no influence in anti-clockwise rotation of the mandible. Themandibular growth was also observed after the orthodontic treatment, suggesting that it is influenced bygenetic factors. Conclusion: These observations may lead to the peculation that growing patients with skeletal Class II malocclusion and low mandibular plane are conducive to a good treatment and long-term stability.

Alterações do perfil médio facial no tratamento da má-oclusão de classe II de Angle com aparelho de Kloehn / Alterations of the face media profile in the treatment of the malocclusion of Angle Class II with Kloehn apliance

A presente pesquisa foi retrospectiva e desenvolvida com o intuito de avaliar as alterações ocorridas no perfil médio facial em pacientes Classe II, Divisão I, de Angle, tratados com o aparelho extrabucal de Kloehn. A amostra foi selecionada e constituída de 30 indivíduos, sendo 18 indivíduos para o grupo experimental e 12 indivíduos para o grupo controle. Foram realizadas telerradiografias no início (TI) e no final (T2) do tratamento para todos os indivíduos. A média de idade no início do tratamento do grupo experimental foi de 9,3 anos e de 10,6 anos para o grupo controle. Os resultados foram obtidos através de medidas cefalométricas tradicionais e pelo movimento dos pontos cefalométricos relacionados ao perfil mole em relação às coordenadas X e Y, obtidas 7° para baixo em relação à linha sela-násio (S-N). As respostas ao tratamento e as alterações provocadas pelo crescimento normal, foram analisadas e comparadas por meio do teste "t" de Student e o teste de Levene aplicado para a análise das variâncias. Foi realizada avaliação da reprodutibilidade do erro do método com índice de concordância acima de 98%. O tratamento com aparelho extrabucal de Kloehn para pacientes em Classe ll, Divisão I, de Angle, não apresentou alterações estatisticamente significantes em relação ao perfil mole facial, ângulo nasolabial, espessura e comprimento do lábio superior, comparado ao grupo não tratado. Por outro lado, houve uma resposta estatisticamente significante (p<0,05) quanto à restrição do deslocamento anterior da maxila com resultados esqueléticos e dento alveolares para a correção desta má-oclusão.

This research was retrospect and developed with intention to evaluate changes occurred in thefacial media profile inpatients class II division 1 of Angle, treated with the Kloehn headgear appliance. The sample was selected and consisted of 30 individuais, I 80 flhe experimental group and 12 of the control group. Cephalometric radiographs for ali patients were taken at the pretreatment (TI) and posl treatment (T2). The average age pre treatment of experimental group was 9,3 years, and for the group control was 10,6 years. The results had been described through traditional cephalometrics measures and for movement of related cephalometrics points to the soft profile in relation to coordinates X and Y, gotten 70for low in relation to the sela nasio line (S-N). The changes showed by the normal growth, had been analysed and compared by means t Student test and the Levene test was appliedfor lhe analysis ofthe variances. Evaluation of reprodutibility (error ofthe method) with index of agreement above of98% was realized. The treatment with Kloehn headgear appliance for patients Angle Class 11, Divisionl did not showed significant statistical changes in relation to lhe facial soft profile, nasolabial angle, thickness and length of the superior lip, when compared with un treatment group. On the other hand, it had results statistical significant (p<0,05) to the restriction of the anterior displacement of the jaw withskeletals and dento alveolars results for the correction of this mal occclusion.

Estudo da reabsorção radicular apical após o uso de aparelho extrabucal no tratamento da má oclusão do tipo Classe II, 1ª divisão dentária / Study of apical root resorption after occipital headgear wear on the treatment of dental Class II, division 1 malocclusion

OBJETIVO: o presente estudo verificou o efeito do uso do aparelho extrabucal (AEB) sobre a intensidade da reabsorção radicular apical nos primeiros molares permanentes superiores submetidos à ação do aparelho. MÉTODOS: foram avaliadas as radiografias periapicais da região dos primeiros molares permanentes superiores, bilateralmente, de 19 jovens leucodermas, do gênero feminino, com idades entre 8 e 10 anos, com má oclusão do tipo Classe II, 1ª divisão dentária, pré e pós-tratamento com AEB de tração alta. As 76 radiografias foram divididas em dois grupos, de acordo com o grau de formação radicular. O grupo A consistiu de 18 radiografias com formação radicular incompleta, com exceção da raiz palatina, ao início do tratamento e 18 ao final. O grupo B consistiu de 20 radiografias com formação radicular completa ao início do tratamento e 20 ao final. Mensurou-se os comprimentos radiculares utilizando um paquímetro digital e submeteu-se as medidas obtidas ao teste de erro do método e à análise estatística (teste t de Student) para verificar as diferenças no comprimento radicular antes e após o tratamento com o AEB. RESULTADOS: no grupo A ocorreu um aumento significativo dos comprimentos radiculares, enquanto no grupo B as diferenças dos comprimentos radiculares não foram significativas. As medidas pós-tratamento no grupo A não diferiram das medidas pré-tratamento no grupo B, ou seja, os dentes com formação radicular incompleta ao início do tratamento apresentaram crescimento radicular normal durante o tratamento ativo. CONCLUSÃO: concluiu-se que o uso do AEB não influenciou negativamente na formação radicular e não provocou reabsorção apical nos molares submetidos à ação do aparelho, sugerindo que o AEB não apresentou riscos à estrutura e formação radicular quando corretamente indicado e aplicado.

AIM: The aim of this study was to verify the effect of occipital headgear wear on the intensity of apical root resorption of the upper first permanent molars submitted to the action of the appliance. METHODS: Were evaluated periapical X-rays of 19 leucoderms young female - with ages between 8 and 10 years, with dental Class II, division 1 malocclusion, before and after orthodontic treatment, using high-pull headgear. The 76 X-rays were divided into two groups according to their root formation. Group A consisted of 18 X-rays with incomplete root formation, except for the palatine root, before treatment and 18 after treatment. Group B consisted of 20 X-rays where root formation was completed before treatment and 20 after treatment. The root lengths were measured with digital caliper and the registered measures were submitted to the error of the method and statistical analysis, Student t test, to verify the differences regarding the root length before and after the treatment with occipital headgear. RESULTS: In group A, there was a significant increase of the root lengths, while in the group B the differences were not significant. Posttreatment Group A showed no significant differences with the mean root lengths of pretreatment group B, in other words, teeth with incomplete root formation at onset of orthodontic treatment presented normal root growth during the active treatment. CONCLUSION: Therefore, it was concluded that high-pull headgear didn't influence negatively in the root formation and it didn't provoke apical resorption of the molars submitted to the action of the appliance, suggesting that occipital headgear doesn't present risks to the root structure and formation when correctly indicated and applied.

Relación esquelética en la Clase II de Angle con crecimiento vertical por rotación posterior de la mandíbula: tratamiento con casquete extraoral de tracción alta y placa acrílica maxilar: observaciones clínicas y reporte de un caso / Skeletal class II relationship with vertical development and posterior mandibular rotation: highpull headgear and maxillary orthopedic splint treatment: clinic observations and a case report

El tratamiento ortopédico en pacientes que presentan una relación esquelética de clase II con crecimiento vertical por rotación mandibular posterior constituye un verdadero reto para el ortodoncista. La dirección y rotación del crecimiento maxilar y mandibular, a veces, dificulta la corrección de la discrepancia intermaxilar cuando se utilizan solamente aparatos ortopédicos.

Orthopedic correction of Class II Skeletal jaw discrepancies in growing children is a widely accepted treatment approach. The combination of maxillary orthopedic splints or activators with various extra oral appliances has been recommended for maximum orthopedic effect. This combination appears to allow better control of the vertical growth component, which is a critical factor in the correction of sagital skeletal jaw discrepancies.

C-activator treatment for distalization of maxillary molars in Class II anterior deep bite malocclusion / 대한치과교정학회지

A modified removable appliance for molar distalization called C-activator was used in a 10-year old male patient with a Class II anterior deep bite malocclusion with upper arch discrepancy. The treatment plan involved correcting the Class II relationship, distalizing both upper first molars, and regaining space for the erupting canines. The C-activator, which was used for 6 months, consisted of a labial framework formed from .036-in stainless steel wire and an acrylic monobloc. Both the closed helices of the labial framework were compressed for reactivation during the C-activator treatment period. C-activator mechanics simultaneously achieved distalization of the upper first molars into their proper positions and repositioning of the mandible. After 21 months of treatment, the correct overbite and overjet was obtained and contributed to an improvement in facial balance. The treatment results were stable 6 months after debonding. Fabrication and placement of the new appliance and clinical procedures are detailed, and the treatment sequence and results of this case are presented as follows.

A photoelastic evaluation of stress distribution during distal movement of upper molar / 대한치과교정학회지

The purpose of this study was to photoelastically visualize the distribution of forces transmitted to the alveolus and surrounding structures using three different types of headgear for the distal movement of the upper molars. A photoelastic maxillary model was made and three different directional forces applied, which were high-pull, straight- pull, and cervical-pull. Stress distribution was recorded through circular polariscope, and two-dimensional photoelastic stress analysis was performed according to isochromatic fringe characteristics. The results were as follows: 1. In the case of high-pull headgear, bodily movement occurred in the medium-length outer bow, stress distribution in the apical region was 1st molar, 2nd premolar, 1st premolar in sequence and there was no apparent difference. 2. In the case of straight-pull headgear, bodily movement occurred in the long outer bow and stress distribution in the apical region was heavy in the 1st molar, 2nd premolar, 1st premolar in sequence. But, there were no apparent differences according to the length of the outer bow. 3. In the case of cervical-pull headgear, bodily movement also occurred in the long outer bow, and apical stress of the premolar region was heaviest among other cases and apical stress of the 2nd premolar was heaviest in the short outer bow. In clinical situations, to achieve bodily movement of the upper 1st molars without modifying outer bow height, applying an outer bow length as long as the inner bow length in high-pull headgear and applying an outer bow length longer than the inner bow length in straight-pull, cervical-pull headgear are recommended.

Treatment effects of the Teuscher appliance in skeletal Class II division 1 malocclusion / 대한치과교정학회지

Various methods have been used on patients with skeletal Class II division 1 malocclusion. The activator, Frankel appliance, headgear, Herbst appliance, and Twin-block appliance are some examples. The ideal treatment effect using these appliances would be to inhibit horizontal and vertical growth of the maxilla while promoting mandibular growth and obtaining optimum dentition. The Teuscher appliance has a simultaneous combined headgear effect with maxillary growth inhibition and an activator effect with mandibular growth promotion. The purpose of this study was to examine how well these effects were clinically obtained and the results are as follows. 1. The forward growth of the maxilla was effectively inhibited. 2. The downward-forward growth of the maxillary dentoalveolar complex was inhibited. 3. Growth promotion of the mandible was not observed. 4. The overjet, overbite, molar key were effectively improved. 5. The protruded upper lip and facial profile were improved.