Revisión de los principales manejos ortodónticos interceptivos y correctivos no quirúrgicos de la maloclusión clase III / Review of the main non-surgical interceptive and corrective orthodontic management of Class III malocclusion

La maloclusión clase III se considera un reto en la práctica de todo ortodoncista. Una de las principales dudas al respecto reside en ¿cuándo es el mejor momento para intervenir? Exis- ten dos enfoques en el manejo ortodóntico del paciente: 1) la ortodoncia interceptiva; y 2) la ortodoncia correctiva. La or- todoncia interceptiva busca la prevención del establecimiento de la malolcusión. En este grupo, se encuentra el uso de más- cara facial con disyunción maxilar y el de aparatología fija (2x4 o 2x6). Por otro lado, la intervención correctiva hace re- ferencia al camuflaje de las características que trae consigo la maloclusión clase III ya establecida; dentro de este enfoque se encuentran las extracciones de piezas, el uso de minitornillos extraalveolares y la filosofía MEAW. Se puede concluir que el adecuado manejo de la maloclusión clase III radica en el oportuno y correcto diagnóstico, que debe realizarse a través de la minuciosa inspección de las características y hallazgos intra y extraorales de los pacientes (AU)

Class III malocclusion is considered a challenge in the practice of every orthodontist. One of the main questions is: when is the best time to intervene? There are 2 approaches to the orthodontic management of the patient: 1) interceptive orthodontics, and 2) corrective orthodontics. Interceptive or- thodontics seeks to prevent the establishment of malocclusion by means of the use of a facial mask with maxillary disjunc- tion, or the use of fixed appliances (2x4 or 2x6). Corrective intervention refers to camouflaging the characteristics of a Class III malocclusion that is already established. This ap- proach uses tooth extraction, extra-alveolar mini screws or the MEAW philosophy. To conclude, proper management of Class III malocclu- sion is based on timely, correct diagnosis, which must be made through careful inspection of the characteristics and intraoral and extraoral findings in patients (AU)

Spontaneous Transversal Changes of Lower Arch Following Palatal Skeletal Expansion

ABSTRACT Objective: To evaluate how the lower arch spontaneously change after upper rapid palatal expansion in a group of patients with transversal skeletal deficit. Material and Methods: Twenty-four patients treated by the same orthodontist with a rapid palatal expander (RPE) bounded on a deciduous molar have been selected. The sample was divided into two groups: no treatment was provided for group one, while group two was treated using a lip bumper or Schwarz appliance. For each patient, dental casts were collected when the RPE was bounded (T0) and at the end of treatment, 9 months ± 3 months later (T1). Each outcome was analyzed, providing descriptive statistics, main effects significance tests and post-hoc analyses with the objective to evaluate the variations between pre-treatment (TO) and post-treatment (T1) of each of them. Results: If the linear measurements are considered, a significant beneficial effect on both arches is observed. However, the upper arch always shows a major increase of all values at T1 with respect to the lower arch. Even though the post-hoc tables indicate that time differences are all statistically significant across considered partitions, the lower arch's increase is more pronounced in group two, where patients were treated in both arches. If the angular measurements are concerned, the increase of lingual crown inclination was found in all patients, independently from the type of treatment in lower arch. Conclusion: All patients show normalization of upper diameters, regardless of whether the lower arch was treated or not.

Corrección de la maloclusión y de la postura / Correction of malocclusion and posture

La maloclusión dentaria se encuentra en íntima relación con la postura del paciente y la dinámica funcional, la resolución de estos tres aspectos solo podrá ser efectiva y estable en el tiempo con un tratamiento de forma integral. Por lo tanto, a los objetivos ortodóncicos ­que hablan de: estética facial, estética dentaria, salud periodontal, estabilidad de la ATM, oclusión funcional, motivo de la consulta­ debemos agregar, estabilidad postural.

Efectividad de la Expansión Maxilar en la Corrección de Apiñamiento en Dentición Mixta. Revisión Sistemática / Effectiveness of the Maxillary Expansion in the Correction of Crowding and Mixed Dentition. Systematic Review

RESUMEN: El apiñamiento en edades tempranas, se refleja cuando el tamaño dental no coincide con la longitud de arco. De este modo, resulta importante determinar si la expansión del maxilar podría solucionar por sí solo el problema de apiñamiento en el sector anterior, teniendo en cuenta que este tratamiento es uno de los más antiguos y que comúnmente se ha enfocado en la resolución de alteraciones transversales en dientes posteriores empleándose a edades tempranas. El objetivo fue determinar si la expansión maxilar es efectiva o no, en la corrección del apiñamiento en dentición mixta mediante el análisis de la evidencia disponible. Se realizó una revisión sistemática en español e inglés, para establecer la máxima evidencia posible, con las indicaciones de la guía PRISMA. Dos artículos cumplieron con la calidad de la revisión. En el primero se estableció que el apiñamiento mejoro despues del tratamiento de expansion maxilar, con una recidiva menor en la dentición permanente. En el segundo, se encontró que el apiñamiento en los incisivos permanentes superiores fue corregido cuando se retiró el aparato expansor. Se concluyó que la evidencia actual no tiene la suficiente calidad metodológica para llevar a una toma de decisión. Se recomienda hacer ensayos clínicos aleatorizados en este tema.

ABSTRACT: Crowding at early ages is reflected when tooth size does not coincide with arch length. Thus, it is important to determine whether maxillary expansion alone could solve the problem of crowding in the anterior sector, bearing in mind that this treatment is one of the oldest and has commonly focused on solving transverse alterations in posterior teeth used at an early age. The objective was to determine whether or not maxillary expansion is effective in correcting crowding in the mixed dentition by analysing the available evidence. A systematic review was carried out in Spanish and English, to establish the maximum possible evidence, with the indications of the PRISMA guide. Two articles met the quality of the review. The first established that crowding improved after the treatment of maxillary expansion, with a minor recurrence in the permanent dentition. In the second, it was found that crowding in the upper permanent incisors was corrected when the expanding appliance was removed. The current evidence is not of sufficient methodological quality to lead to a decision. Randomized clinical trials are recommended in this area.

Effects of the cervical headgear in growing Angle Class II malocclusion patients: a prospective study

ABSTRACT Objective: Evaluate dental and skeletal changes resulting from the exclusive use of the cervical headgear for 15 ± 4 months in the treatment of patients with Class II division 1 malocclusion. Methods: Differences between the beginning (T1) and immediately after the end of the therapy (T2) with the cervical headgear in growing patients (Experimental Group, EG, n = 23) were examined and compared, during compatible periods, with those presented by a group of untreated individuals (Control Group, CG, n =22) with similar malocclusions and chronological age. The cephalometric variables evaluated were: ANB, GoGn.SN, AO-BO, S'-ANS, S'-A, S'-B, S'-Pog and S'-U6 (maxillary first molar). The Shapiro-Wilk and Levene tests were used to evaluate the results. Results: Significant differences were found relative to the ANB, S'-U6, AO-BO, S'-ANS, S'-A, S'-B and S'-Pog variables between T1 and T2 when comparing both groups. No statistically significant variation was found regarding the GoGn.SN angle. Conclusions: The use of cervical headgear promoted distal movement of the maxillary first molars and restricted the anterior displacement of the maxilla, without significantly affecting the GoGn.SN angle.

RESUMO Objetivo: Avaliar as alterações dentárias e esqueléticas decorrentes do uso exclusivo do aparelho extrabucal durante 15 ± 4 meses para tratamento de pacientes com má oclusão de Classe II divisão 1 (Grupo Experimental, GE). Métodos: As diferenças entre o início (T1) e imediatamente após o término da terapia (T2) com o aparelho extrabucal de tração cervical (Grupo Experimental, GE, n = 23) foram comparadas àquelas apresentadas por um grupo composto por indivíduos não tratados (Grupo Controle, GC, n = 22), com má oclusão e faixa etária cronológica compatíveis. As variáveis cefalométricas avaliadas foram: ANB, GoGn.SN, AO-BO, S'-ENA, S'-A, S'-B, S'-Pog e S'-U6 (primeiro molar superior). Os testes de Shapiro-Wilk e Levene foram aplicados para avaliar os resultados. Resultados: Diferenças significativas entre T1 e T2 foram encontradas para as variáveis ANB, S'-U6, AO-BO, S'-ENA, S'-A, S'-B e S'-Pog, quando comparados os dois grupos. Nenhuma diferença estatisticamente significativa foi encontrada em relação ao ângulo GoGn.SN. Conclusão: O uso do aparelho extrabucal com tração cervical promoveu movimento para distal do primeiro molar superior e restringiu o deslocamento anterior da maxila, sem afetar significativamente o ângulo GoGn.SN.

Tratamiento de la hipoplasia anteroposterior maxilar / Treatment of anteroposterior maxillary hypoplasia

RESUMEN Los pacientes con hipoplasia anteroposterior del maxilar superior deben ser detectados durante la atención odontológica temprana, o sea, cuando todavía están en período de crecimiento, con la finalidad de poder inducir cambios de tipo alveolar, esqueléticos y estéticos. La paciente tenía 12 años de edad, contaba con potencial remanente de crecimiento y presentaba Síndrome de Clase III esqueletal, por retrusión del maxilar superior. La caracterizaba una mandíbula de tamaño normal y una mordida cruzada anterior; en su tratamiento se utilizó la máscara facial ortopédica de Petit, para la tracción anterior del maxilar, y el tornillo Hyrax, para la expansión dentoalveolar. Estos instrumentos se emplearon con el fin de corregir la mordida cruzada posterior simple del lado izquierdo. Se observaron resultados satisfactorios desde el punto de vista esqueletal, oclusal, faciales y del perfil.

ABSTRAC Patients with anteroposterior hypoplasia of the upper jaw should be detected during early dental care, that is, when they are still growing, in order to be able to induce alveolar, skeletal and aesthetic changes. The patient was 12 years old, had residual growth potential and presented skeletal Class III Syndrome due to retrusion of the upper jaw. She was characterized by a normal sized jaw and an anterior crossbite; a Petit orthopedic face mask was used as a treatment for anterior maxillary traction and a Hyrax screw for dentoalveolar expansion. These instruments were used in order to correct the simple posterior crossbite on the left side. Satisfactory results were observed from the skeletal, occlusal, facial and profile points of view.

Manejo ortodóncico de la clase III: presentación de un caso clínico / Orthodontic management of class III: presentation of a clinical case

Introducción: La maloclusión clase III es considerada como severa y en la mayoría de los pacientes la etiología suele estar combinada entre componentes esqueléticos y dentoalveolares. Las posibilidades terapéuticas dependerán de la edad biológica del paciente y del tipo de maloclusión. Conforme va aumentando la edad del paciente va menguando la capacidad de crecimiento y se va asentando la relación de clase III esquelética. Las maloclusiones de clase III esqueléticas se pueden corregir mediante extracciones dentales y cirugía ortognática. Caso clínico: Paciente masculino de 13 años de edad con protrusión mandibular, discrepancia óseo dentaria negativa, convexidad facial disminuida y clase III dental y esqueletal. Resultados: Se resolvió la discrepancia óseo dentaria negativa del paciente, se logró la clase I Molar y canina con una sobremordida adecuada (AU)

Introduction: Class III malocclusion is considered severe and in most patients the etiology is usually combined between skeletal and dentoalveolar components. The therapeutic possibilities depend on the biological age of the patient and the type of malocclusion. As it increases the age of the patient wanes growth capacity and Will settled the relationship skeletal class III. The skeletal class III malocclusion can be corrected by tooth extractions and orthognathic surgery. Case report: Male patient 13 years old with mandibular protrusion, negative tooth bone discrepancy, decreased facial convexity and dental and skeletal class III. Results: Dental patient refusal bone discrepancy was resolved, I molar and canine class and adequate overbite was achieved (AU)

Meta-analysis of the efficacy of bone anchorage and maxillary facemask protraction devices in treating skeletal class Ⅲ malocclusion in adolescents / 华西口腔医学杂志

OBJECTIVE@#To assess the efficacy of bone anchorage and maxillary facemask protraction devices in treating skeletal class Ⅲ malocclusion in adolescents.@*METHODS@#Articles relating to the use of bone anchorage and maxillary facemask protraction devices for treating skeletal class Ⅲ malocclusion in adolescents were searched from the databases of Cochrane Library, PubMed, EmBase, CNKI, and Wanfang database. Several inclusion and exclusion criteria were developed for the article screening. The clinical data were extracted, and the quality of the selected articles was evaluated. A Meta-analysis of SNA, SNB, ANB, ANS-Me, Wits, and U1-PP change was performed by using RevMan 5.3.@*RESULTS@#Seven studies (264 patients) were included in the Meta-analysis. Among these studies, three were randomized controlled trials, and four were non-randomized controlled trials. Compared with the maxillary facemask protraction device group, the bone ancho-rage device group had higher SNA changes and lower ANS-Me, Wits, and U1-PP changes (P<0.05). No significant differences were observed in the SNB and ANB changes between these two groups.@*CONCLUSIONS@#Compared with the maxillary facemask protraction device, the bone anchorage device can increase the extent of protraction of the maxilla and has better controls for the labial inclination of the maxillary anterior teeth in treating skeletal class Ⅲ malocclusion among adolescents. However, additional high-quality randomized controlled trials must be performed to verify the results.

El paciente ortodóncico en dentición mixta y los trastornos del sueño / The orthodontic patient with mixed dentition and sleep disorders

Los desórdenes respiratorios del sueño (DRS) y, principalmente, roncopatías y apneas obstructivas afectan aproximadamente al 7% de los pacientes ortodóncicos. Los DRS no solo son importantes por la cantidad de pacientes afectados, sino por la gravedad de los posibles efectos secundarios a nivel de la salud general del paciente. La obstrucción de las vías aéreas superiores (VAS) provoca alteraciones del crecimiento y deformaciones craneofaciales importantes, por lo que el tratamiento temprano y la prevención de la respiración oral es muy importante.El papel del ortodoncista es muy importante en el diagnóstico y en el tratamiento de los DRS, pero también en su prevención, realizando tratamientos que aumenten la dimensión y la permeabilidad de las VAS. El protocolo de exploración interdisciplinar en niños y adolescentes y la cefalometría de vías aéreas son importantes en el diagnóstico y deben ser tenidos en cuenta en el plan de tratamiento. Pero las pruebas más significativas, el CBCT de vías aéreas y la polisomnografía no son pruebas rutinarias por la dificultad logística y el precio de estas pruebas. En este artículo también se recomiendan los tratamientos de ortodoncia más indicados en estos casos y que tienden al aumento de la dimensión de las VAS (AU)

Sleep breathing disorders (SBD) and in the first place, roncopathy and obstructive apnea, affect approximately 7% of orthodontic patients. The SBD are not only important for the number of affected patients, but also for the severity of the possible side effects at the level of general health of a patient. The upper air ways (UAW) obstruction provokes important alterations in growth and craniofacial deformations, and this is why the early treatment and prevention of mouth breathing are very important. The role of an orthodontist in diagnosis and treatment of SBD is very important, but it is also in its prevention, carrying out the treatments which increase the dimension and permeability of UAW. The protocol of interdisciplinary examination.In children and adolescents and the air ways cephalometry analysis have an important role in diagnosis and they should be taken into account in treatment planning. But the most important tests, the air ways CBCT and polysomnography, are not routine tests due to the complicated logistics and their cost. In this article, the orthodontic treatments most indicated in these cases are recommended, because they tend to increase the UAW dimension (AU)

Distancia intercanina en niños con dentición temporal, mixta y permanente / Intercanine distance in children with temporary, mixed and permanent dentition

RESUMEN Introducción: Los valores de la distancia intercanina representan una referencia auxiliar útil, para predecir problemas de deficiencia de espacio relacionados con el crecimiento transversal de los maxilares. Objetivo: Determinar los valores de la distancia intercanina en niños con oclusión normal en ambas arcadas dentarias y distintos períodos de dentición. Métodos: Fue realizado un estudio de tipo descriptivo y transversal. El universo estuvo comprendido por 6 033 escolares, de los cuales se obtuvo una muestra aleatoria estratificada de 525 niños con edades de 3, 6, 9 y 12 años, seleccionados de acuerdo con las etapas de desarrollo dental: dentición temporal, mixta temprana, tardía y permanente. Fue realizado un examen clínico facial y bucal, para lo cual se aplicaron los criterios de inclusión. Las variables fueron: edad, sexo y distancia intercanina superior e inferior. Para valorar la posible existencia de asociación entre la distancia intercanina y el sexo, así como con la edad, se utilizó la prueba t de Student para muestras independientes y el análisis de varianza (ANOVA), respectivamente. Resultados: La distancia intercanina superior a los 3 años fue: 27,3 mm, 6 años: 30,42 mm, 9 años: 31,67 y 12 años: 32,93 mm, e inferior (23,19 mm, 24,66 mm, 25,61 y 25,98 mm) para los 3, 6, 9, y 12 años, respectivamente. El sexo masculino mostró los mayores valores. Se comprobaron diferencias significativas en relación con el sexo en la distancia intercanina superior a los 6 y 12 años (p= 0,000) y en la inferior en las mismas edades (p= 0,001 y p=0,01), entre las edades (p= 0,000) tanto en superior como inferior. Conclusiones: La distancia intercanina se incrementa en ambos maxilares conjuntamente con la edad. Se comprueba un predominio de mayor anchura del sexo masculino a los 6 y 12 años en ambos maxilares(AU)

ABSTRACT Introduction: Intercanine distance values are a useful auxiliary reference to predict space deficiency problems related to transverse maxillary growth. Objective: Determine intercanine distance values for children with normal occlusion in both dental arches during the different dentition periods. Methods: A descriptive, cross-sectional study was conducted. The study universe was 6 033 schoolchildren, from whom a stratified random sample was selected of 525 children aged 3, 6, 9 and 12 years, corresponding to the stages of dental development: temporary, early mixed, late mixed and permanent dentition. Facial and oral clinical examination was performed, based on the inclusion criteria. The variables studied were age, sex, upper intercanine distance and lower intercanine distance. The possible association between intercanine distance and sex and age was determined with Student's independent samples t-test and analysis of variance (ANOVA), respectively. Results: Upper intercanine distance was 27.3 mm at 3 years, 30.42 mm at 6 years, 31.67 mm at 9 years and 32.93 mm at 12 years. Lower intercanine distance was 23.19 mm, 24.66 mm, 25.61 mm and 25,98 mm at 3, 6, 9 and 12 years, respectively. Male subjects exhibited greater values. Significant differences were found with respect to sex in upper intercanine distance at 6 and 12 years (p= 0.000) and in lower intercanine distance at the same ages (p= 0.001 and p=0.01), as well as in upper and lower intercanine distance across the different ages (p= 0.000). Conclusions: Intercanine distance increases in both jaws with age. A predominance was found of a greater width in the male sex in both jaws at 6 and 12 years of age(AU)

Comparison of two asymmetric headgear force systems: A finite element analysis

Abstract Objective: The aim of this study was to evaluate the effect of displacement patterns of the molar teeth in response to different asymmetric headgear loading using 3D finite element method. Methods: A series of twenty-five facebow with different left vs. right outer bow length and different expansion of left vs. right were designed. The non-favored side (right side) was shortened at intervals of 10 mm, and favored side (left side) was expanded 10 degree greater than right side and 5 degree expansion were successively added. At the first phase, each side received 200-g load, implying the neck strap to displace toward shorter arm. At the second phase, a total of 400-g load was applied to the ends of the outer bow. Because of the neck strap displacement, the shorter arm received greater load than the left side, the magnitude of the applied force to each side depended on difference of left vs. right outer bow length and expansion. Results: All systems were effective in promoting asymmetric distal movement of the molars. However, the asymmetrical facebow with the 40 mm shortening and 25 degree expansion outer bow when unequal force applied could be used in asymmetric mechanics. Medial and occlusal displacing forces were observed in all systems. Conclusions: Both equal and unequal force application is effective for molar distalization. Expansion of the outer bow in the affected side and shortening of the outer bow in the normal side were effective to produced differential distal molar movement.

Resumo Objetivo: o objetivo desse estudo foi usar o método de elementos finitos 3D para avaliar o efeito no padrão de deslocamento dos molares em resposta ao uso de aparelhos extrabucais com diferentes forças assimétricas. Métodos: foram confeccionados 25 aparelhos extrabucais (AEB) com diferenças, entre os lados direito e esquerdo, quanto ao comprimento e ao grau de abertura do braço externo. O lado não favorecido (lado direito) foi encurtado em intervalos de 10 mm e o lado favorecido (lado esquerdo) foi aberto 10 graus a mais do que o lado direito, sendo adicionados 5 graus de abertura sucessivamente. Na primeira fase, cada lado recebeu carga de 200 g, causando o deslocamento da tala cervical em direção ao braço mais curto. Na segunda fase, foi aplicada carga total de 400 g às extremidades dos braços externos dos AEB. Devido ao deslocamento da tala cervical, o braço mais curto recebeu uma força maior do que o lado oposto; a magnitude da força aplicada em cada lado dependeu da diferença no comprimento e na abertura dos braços externos do AEB. Resultados: todos os sistemas foram efetivos em promover movimentação distal assimétrica dos molares. Porém, o AEB assimétrico com 40 mm de encurtamento e 25 graus de abertura do braço externo poderia ser usado na mecânica assimétrica, com aplicação diferenciada de força. Foram observadas forças mediais e oclusais de deslocamento em todos os sistemas. Conclusões: tanto a aplicação de forças simétricas quanto assimétricas são efetivas para a distalização dos molares. A expansão do braço externo do AEB no lado afetado e o encurtamento no lado normal foram efetivos na produção de movimento distal assimétrico dos molares.

Frenectomía lingual láser asistida como coadyuvante del tratamiento de ortopedia maxilar / Laser-assissted lingual frenectomy as a coadjuvant to maxillary orthopedic treatment

La aplicación del LÁSER (light amplification of stimulation emision of radiation) en las áreas de la medicina y la odontología viene demostrando una constante evolución, brindándonos alternativas a los tratamientos convencionales. Los láseres quirúrgicos de tejidos blandos muestran grandes ventajas comparados a los procedimientos habituales de corte, ya sea con bisturí frío o electrobisturí. La mínima necesidad de anestesia, la analgesia intra y postoperatoria, la coagulación inmediata, la cicatrización por segunda, el efecto bactericida, la ausencia de puntos de sutura, el confort postoperatorio, son algunas de las ventajas que hacen que la cirugía con láser sea una opción indiscutible que está ganando terreno entre los profesionales de la salud (AU)

Morphological changes of skeletal class III malocclusion in mixed dentition with protraction combined activities / Cambios morfológicos en maloclusión de la clase esquelética III en dentición mixta con actividades combinadas de protracción

The objective of the study was to investigate the morphological changes of skeletal class III malocclusion in mixed dentition with light force protraction combined activities. Randomly selected 30 cases of orthodontics in Shanxi Medical University orthodontics patients (ages: 6-10 years) of the lateral cephalograms. Using the oral maxillary casting type of pre-traction device, according to the condition of maxillary dentition to select the corresponding activities of the movable expansion appliance, each side of the force of about 150-200 g, requiring patients to wear 10-12 hours a day, the appliance should be removed after reaching normal occlusion. The correlation cephalometric profile of the cranial lateral radiographs before and after orthodontic treatment was measured. All patients with skeletal class III malocclusion were improved, concave type became direct type, measurements SNA, ANB, A-Ptm, MP-SN, ANS-Me/N-Me increased, maxillary advancement and reconstruction are more obvious; mandible rotates clockwise; the increase of lip inclination of anterior teeth compensatory changes, lower anterior tooth inclination changes smaller; upper lip forward, nasolabial angle decreased, improved appearance significantly. Light force protraction combined activities can make the mixed dentition of skeletal class III malocclusion in patients with significant improvement in profile appearance.

El objetivo de este estudio fue investigar los cambios morfológicos de la maloclusión clase esquelética III, en la dentición mixta, con actividades combinadas de protracción de la fuerza ligera. Se seleccionaron aleatoriamente 30 casos de ortodoncia en pacientes de ortodoncia de la Universidad Médica de Shanxi (edades: 6-10 años) a partir de cefalogramas laterales, utilizando el tipo de dispositivo de pretracción de vaciado maxilar oral, de acuerdo con la condición de la dentición maxilar para seleccionar las actividades correspondientes del dispositivo de expansión móvil, cada lado con fuerza de alrededor de 150-200 g, requiriendo que los pacientes los utilizaran de 10 a 12 horas al día. El dispositivo debía ser retirado después de alcanzar la oclusión normal. Se midió el perfil cefalométrico de correlación de las radiografías laterales craneales, antes y después del tratamiento ortodóncico. Se observó mejoramiento en todos los pacientes con maloclusión de clase esquelética. Las mediciones SNA, ANB, APtm, MP-SN, ANS-Me / N-Me aumentaron, el avance y la reconstrucción maxilar fueron los cambios más significativos; la mandíbula giró en el sentido de las agujas del reloj, se observó un aumento de la inclinación labial de los dientes anteriores. Fue reducida la inclinación anterior del diente inferior, el ángulo nasolabial disminuyó y en general mejoró significativamente la apariencia. Las actividades combinadas de protrusión de la fuerza radiante pueden llevar a una mejora signficativa en el perfil de pacientes con dentición mixta de maloclusión clase III.

Disyunción Maxilar / Maxillar disjunction

RESUMEN La disyunción maxilar rápida es un procedimiento ortopédico en el que se realizan una serie de activaciones diarias a un tornillo de expansión que actúa sobre la sutura palatina media y provoca la apertura de la misma en un breve período de tiempo, puede acompañarse de excesiva sintomatología en los pacientes. El objetivo de este trabajo es mostrar los beneficios aportados por la disyunción palatina del maxilar al aplicar solamente una activación diaria (1/4 de vuelta). Para ello se empleó un tornillo tipo Hyrax en un paciente masculino de 14 años de edad que presentaba una maloclusión dental de Clase III de Angle (Sindrómica Clase I), acompañada de un micrognatismo transversal superior mayor de 4 mm, una mordida cruzada posterior bilateral y presencia de curva de Monzón, que indica endognasia del maxilar. En un período de tiempo de siete semanas se logró la apertura de la sutura palatina media y por consiguiente, el incremento de la longitud del arco dentario, la eliminación del apiñamiento además de la corrección de la mordida cruzada anterior y posterior bilateral, con escasa sintomatología referida por el paciente (AU).

ABSTRACT The rapid maxillary disjunction is an orthopedic procedure in which an expansion screw acting upon the medial palatal suture, is activated every day and causes its aperture in a short period of time, accompanied by an excessive symptomatology in the patients. The aim of this paper is showing the benefits provided by the maxillary palatal disjunction when activated only once a day (1/4 turn). A Hyrax type screw was used in a 14 years-old male patient who had an Angle´s Class III malocclusion (Syndromic Class I) together with a transversal superior micrognathism larger than 4 mm and a posterior bilateral cross bite with a Monzon´s curve indicating maxillary endognathia. The results showed the expansion of the medial palatal suture in seven weeks and as a consequence the expansion of the dental arch, the alleviation of dental crowding, and the correction of the anterior and posterior bilateral cross bite and what is most important, the distress caused to the patient was minimal AU).

Enmascaramiento en las mesioclusiones / Camouflage in mesiocclusions

Se analiza la difícil tarea de decidir, por parte del especialista, un camuflaje ortodóncico en aquellos pacientes con mesioclusiones verdaderas que no aceptan un tratamiento donde se realice cirugía ortognática. Cuál debe ser el límite que nos impone el caso clínico para poder tomar la decisión de realizar el tratamiento y qué debe esperar el paciente y el profesional en los resultados finales, una vez concluido. Somos los ortodoncistas los que tenemos el deber de decidir qué pacientes podrían ser tratados con camuflaje y cuáles, con cirugía ortognática, pero será el paciente el que tome la decisión final con nuestro asesoramiento (AU)

We discuss the difficult task of deciding, on the part of the specialist, an orthodontic camouflage in those patients with true mesioclusions who do not accept a treatment where orthognathic surgery is performed. What should be the limit imposed by the clinical case in order to make the decision to carry out the treatment and what the patient and the professional should expect in the final results, once concluded. We orthodontists have the duty to decide which patients could be treated with camouflage and which, with orthognathic surgery, but it will be the patient who makes the final decision with our advice (AU)

Tratamiento de ortopedia en niños especiales / Orthopedic treatment in special children

Secuencia de tratamiento con ortopedia maxilar en una niña con síndrome de Down que presenta una mesiorrelación, debido a un maxilar superior chico y retruído y el maxilar inferior grande, con mordida invertida anterior y bilateral, alteraciones funcionales y tipo de crecimiento rotacional anterior, microdoncia y agenesias múltiples (AU)

Treatment with maxillary orthopedics in a girl with Down´s syndrome who presents a mesial relation due to a small and retruded superior maxillary and a big inferior maxillary, with inverted palatal and bilateral bite, functional alterations and palatal rotational growth, microdontia and multiple agenesis (AU)

Compensatory Class III malocclusion treatment associated with mandibular canine extractions

ABSTRACT Skeletal Class III malocclusions are ideally treated with orthodontic-surgical approaches. However, if there are no significant soft tissue implications and the patient does not want to undergo orthognatic surgery, other treatment options may be considered. The current case report describes a compensatory alternative for Class III malocclusion treatment, by means of mandibular canine extractions. This treatment alternative provided facial profile and occlusal improvement, which remains stable seven years posttreatment.

RESUMO As más oclusões esqueléticas de Classe III são idealmente tratadas com intervenções ortodôntico-cirúrgicas. Contudo, se não existirem implicações estéticas faciais e se o paciente não desejar se submeter à cirurgia ortognática, outras opções de tratamento podem ser consideradas. O presente caso clínico descreve um tratamento compensatório alternativo para a má oclusão de Classe III, com extrações de caninos inferiores. Esse tratamento alternativo propiciou melhoras no perfil facial e na oclusão, que permaneceu estável após sete anos da sua finalização.

Distribution of stress on TMJ disc induced by use of chincup therapy: assessment by the finite element method

ABSTRACT Objective: To assess the distribution of stress produced on TMJ disc by chincup therapy, by means of the finite element method. Methods: a simplified three-dimensional TMJ disc model was developed by using Rhinoceros 3D software, and exported to ANSYS software. A 4.9N load was applied on the inferior surface of the model at inclinations of 30, 40, and 50 degrees to the mandibular plane (GoMe). ANSYS was used to analyze stress distribution on the TMJ disc for the different angulations, by means of finite element method. Results: The results showed that the tensile and compressive stresses concentrations were higher on the inferior surface of the model. More presence of tensile stress was found in the middle-anterior region of the model and its location was not altered in the three directions of load application. There was more presence of compressive stress in the middle and mid-posterior regions, but when a 50o inclined load was applied, concentration in the middle region was prevalent. Tensile and compressive stresses intensities progressively diminished as the load was more vertically applied. Conclusions: stress induced by the chincup therapy is mainly located on the inferior surface of the model. Loads at greater angles to the mandibular plane produced distribution of stresses with lower intensity and a concentration of compressive stresses in the middle region. The simplified three-dimensional model proved useful for assessing the distribution of stresses on the TMJ disc induced by the chincup therapy.

RESUMO Objetivo: avaliar, por meio do método dos elementos finitos, a distribuição das tensões no disco articular produzidas pela mentoneira ortopédica. Métodos: um modelo tridimensional simplificado do disco articular foi desenvolvido com o software Rhinoceros 3D e exportado para o software ANSYS. Uma carga de 4,9 N (500 gf) foi aplicada na superfície inferior do modelo, com inclinação de 30, 40 e 50o em relação ao plano mandibular Gônio-Mentoniano (GoMe). O ANSYS analisou, por meio do método dos elementos finitos, a distribuição das tensões presentes no modelo do disco articular para as diferentes angulações. Resultados: os resultados mostraram que a concentração das tensões de tração e compressão foi maior na superfície inferior do modelo. A tensão de tração foi mais presente na região média-anterior do modelo, e sua localização não se alterou nas três direções da aplicação da carga. A tensão de compressão foi mais presente nas regiões média e média-posterior do modelo, mas quando a carga a 50o foi aplicada, ela se concentrou na região média. As intensidades das tensões de tração e compressão diminuíram progressivamente à medida que a carga foi aplicada mais verticalmente. Conclusão: as tensões induzidas pela mentoneira ortopédica se localizaram principalmente na superfície inferior do modelo. As cargas com maior angulação em relação ao plano mandibular produziram uma distribuição de tensões com menor intensidade e uma concentração da tensão de compressão na região média do modelo. Um modelo tridimensional simplificado se mostrou útil na avaliação da distribuição das tensões no disco articular induzidas pela mentoneira ortopédica.

Angle Class III malocclusion with anteroposterior and vertical discrepancy in the final stage of growth

ABSTRACT Angle Class III malocclusion is characterized by an anteroposterior dental discrepancy with or without anteroposterior and vertical skeletal changes. Patients usually seek orthodontic treatment because facial appearance is compromised in most cases. The present study describes the clinical case of a 12-year and 6-month-old girl in her final stage of pubertal growth presenting Class III malocclusion with anteroposterior and vertical discrepancies. Initial treatment consisted of maxillary expansion using a Hass expander followed by the use of a Petit facemask for a minimum of 16 hours a day. During corrective treatment, Class III elastics were used to complement protraction. At the end of the treatment, skeletal discrepancy had improved, and the ANB angle increased from 0 to 2o. Angle Class III malocclusion, anterior crossbite and open bite were corrected. This case was presented to the Committee of the Brazilian Board of Orthodontics and Facial Orthopedics (BBO) as part of the requisites to become a BBO Diplomate.

RESUMO A má oclusão de Classe III de Angle tem como característica uma discrepância dentária anteroposterior, que pode ou não estar acompanhada por alterações esqueléticas tanto no sentido anteroposterior quanto no vertical. O aspecto facial fica comprometido na maioria dos casos, levando o paciente a procurar o tratamento ortodôntico. O presente artigo descreve o caso clínico de uma paciente com doze anos e seis meses de idade, portadora de má oclusão de Classe III, com discrepância anteroposterior e vertical, em fase final de crescimento. O tratamento inicial consistiu de expansão maxilar com o disjuntor de Haas e utilização da máscara facial de Petit por no mínimo 16 horas/dia. Na fase de tratamento corretivo, foram usados elásticos Classe III como complemento à tração reversa. Ao término do tratamento, obteve-se melhora na desarmonia esquelética, com aumento do ângulo ANB de 0o para 2o. Quanto ao padrão dentário, corrigiu-se a relação de Classe III de Angle, o leve cruzamento entre os incisivos e a mordida aberta anterior. Esse caso foi apresentado à Diretoria do Board Brasileiro de Ortodontia e Ortopedia Facial (BBO) como parte dos requisitos para a obtenção do título de Diplomado pelo BBO.

Craniocervical Posture in Children with Class I, II and III Skeletal Relationships

Objective: To describe the characteristics of craniocervical posture of children aged between 6 and 11 years and its relationship to their sagittal skeletal classification. Material and Methods: This descriptive cross-sectional study involved 107 children (55 girls - 52 boys), aged between 6 and 11 years. The sample included no previous orthodontically/orthopedic treated and systemically healthy children. After proper calibration, lateral skull radiographs, taken for diagnosis purpose for maxillary orthopedic treatment, were obtained by the same operator in natural head position. A radiographic analysis was made using a NEMOTEC software: 13 variables were registered: age, gender, ANB angle (to classify sagittal skeletal relationships) and 10 variables related to craniocervical posture: cervical lordosis, hyoid triangle, craniocervical angle, intervertebral spaces: C0-C1, C1-C2 and distances NSL-Ver, NLVer, ML-Ver, OPT-Hor, CVT-Hor. To evaluate the reliability of measures, 15 randomly selected radiographs were re-measured by the same investigator two weeks after the initial analysis. Results: Intra-class correlation coefficients were in a range of 0.945-0.996. Lordosis, CCA, C1-C2, OPT-Hor y CVT-Hor, values were higher in male than in female children (p<0.05). No statistically significant differences were found among groups of sagittal skeletal relationships, but class III children had a tendency to higher craniocervical flexion; 66.3% of the studied group presented rectified lordotic curvature and class II subjects presented increased values of NSL-Ver, NL-Ver and MLVer. Class I children had the lowest values for OPT-Hor and CVT-Hor. Conclusion: All craniocervical postural variables were higher in boys than in girls. No differences were found in this study between cervical postural variables with different malocclusion.