Influence of the cranial base flexion on Class I, II and III malocclusions: a systematic review.

OBJECTIVE: The aim of this study was to perform a systematic review on the morphological characteristics of the skull base (flexion, anterior length and posterior length) and the concomitant development of malocclusions, by comparing differences in dimorphism, ethnicity and age. METHODS: The articles were selected by means of electronic search on BBO, MEDLINE and LILACS databases from 1966 to 2016. A qualitative evaluation of the methodologies used on the articles was also performed. RESULTS: Although the literature on this topic is abundant, only 16 articles were selected for the present systematic review. The cranial base angle itself does not seem to play a significant role in the development of malocclusions. In fact, the cranial base angle is relatively stable at the ages of 5 to 15 years. CONCLUSIONS: A more obtuse angle at the skull base, in association or not with a greater anterior length of the cranial base, can contribute to the development of Class II division 1 malocclusions. On the other hand, a more acute angle at the skull base can contribute to a more anterior positioning of the mandible and to the development of Class III malocclusions.

Molar Uprighting: A Considerable and Safe Decision to Avoid Prosthetic Treatment.

BACKGROUND: Tipped lower molar over edentulous space is very common in orthodontics practice when adults seek treatment. The segmented arch technique features a predictable force system that provides a controlled release of force that can produce light and continuous tooth movement. CASE DESCRIPTION: A female adult patient, who lost a permanent lower first molar, needed correction of the position of her permanent first molar place. Instead of making space for rehabilitation, it was closed after second molar uprighting and a balanced interdigitation was created without prosthetics. The patient was successfully treated with segmented arch technique using root correction spring activated with geometry VI to promote uprighting of a tipped molar and Niti spring coil to promote space closure. PRACTICAL IMPLICATIONS: Segmented arch technique is known to provide predictable light and continuous forces, which is very much indicated in adult treatment. There are several things to consider when orthodontically treating adult patients. Their periodontal conditions might not be ideal, less bone apposition may occur, and side effects of orthodontic tooth movement are expected. Thus, a predictable and controlled orthodontic treatment is needed.

Influence of the cranial base flexion on Class I, II and III malocclusions: a systematic review

ABSTRACT Objective: The aim of this study was to perform a systematic review on the morphological characteristics of the skull base (flexion, anterior length and posterior length) and the concomitant development of malocclusions, by comparing differences in dimorphism, ethnicity and age. Methods: The articles were selected by means of electronic search on BBO, MEDLINE and LILACS databases from 1966 to 2016. A qualitative evaluation of the methodologies used on the articles was also performed. Results: Although the literature on this topic is abundant, only 16 articles were selected for the present systematic review. The cranial base angle itself does not seem to play a significant role in the development of malocclusions. In fact, the cranial base angle is relatively stable at the ages of 5 to 15 years. Conclusions: A more obtuse angle at the skull base, in association or not with a greater anterior length of the cranial base, can contribute to the development of Class II division 1 malocclusions. On the other hand, a more acute angle at the skull base can contribute to a more anterior positioning of the mandible and to the development of Class III malocclusions.

RESUMO Objetivo: o objetivo desse estudo foi realizar uma revisão sistemática sobre as características morfológicas da base do crânio (flexão, comprimento anterior e comprimento posterior) e o desenvolvimento concomitante da má oclusão, comparando as diferenças do dimorfismo, etnia e idade. Métodos: os artigos foram selecionados por meio de busca eletrônica nas bases de dados BBO, MEDLINE e LILACS, de 1966 a 2016. Uma avaliação qualitativa da metodologia dos artigos também foi executada. Resultados: ainda que a literatura seja abundante nesse assunto, somente 16 artigos foram selecionados para a presente revisão sistemática. O ângulo da base do crânio, por si só, não parece desempenhar papel significativo no desenvolvimento das más oclusões. De fato, o ângulo da base do crânio é relativamente estável dos 5 aos 15 anos. Conclusões: um ângulo mais obtuso na base do crânio, associado ou não a um comprimento maior, pode contribuir para o desenvolvimento da má oclusão de Classe II, divisão 1. Por outro lado, um ângulo mais agudo na base do crânio pode contribuir para um posicionamento mais anterior da mandíbula e para o desenvolvimento da má oclusão de Classe III.

Orthodontic Replacement of Lost Permanent Molar with Neighbor Molar: A Six-Year Follow-Up.

Extraction is very frequent indication in orthodontic planning, especially when there are crowding, biprotrusion, and aesthetically unpleasant profiles. Next to extraction comes space closure, which represents a challenge for orthodontists because of extended treatment time, discomfort created for the patient, tissue tolerance, and stability concerns. When it comes to what mechanics to choose for space closure, loops present two major advantages in relation to sliding mechanics: absence of abrasion and possibility to reach pure dental translation. A case is presented where an adult female patient with early loss of the first lower permanent molars, minor lower crowding, and tooth biprotrusion was treated with upper first bicuspids extraction along with upper and lower space closure done with T-loops to promote best space closure control in order to correct the malocclusion and enhance facial aesthetics.

Orthodontic Traction of Impacted Canine Using Cantilever.

The impaction of the maxillary canines causes relevant aesthetic and functional problems. The multidisciplinary approach to the proper planning and execution of orthodontic traction of the element in question is essential. Many strategies are cited in the literature; among them is the good biomechanical control in order to avoid possible side effects. The aim of this paper is to present a case report in which a superior canine impacted by palatine was pulled out with the aid of the cantilever on the Segmented Arch Technique (SAT) concept. A 14.7-year-old female patient appeared at clinic complaining about the absence of the upper right permanent canine. The proposed treatment prioritized the traction of the upper right canine without changing the occlusion and aesthetics. For this, it only installed the upper fixed appliance (Roth with slot 0.018), opting for SAT in order to minimize unwanted side effects. The use of cantilever to the traction of the upper right canine has enabled an efficient and predictable outcome, because it is of statically determined mechanics.

Skeletal and dental changes induced by bionator in early treatment of class II / Alterações esqueléticas e dentárias induzidas pelo bionator no tratamento precoce da classe II

The purpose was to investigate the amount of skeletal and dentoalveolar changes after early treatment of Class II, Division 1 malocclusion with bionator appliance in prepubertal growing patients. Forty Class II patients were divided in two groups. Treated group consisted of 20 subjects treated consecutively with bionator. Mean age at the start of treatment (T0) was 9.1 years, while it was 10.6 years at the end of treatment (T1). Mean treatment time was 17.7 months. Pretreatment and post-treatment cephalometric records of treated group were evaluated and compared with a control group consisted of 20 patients with untreated Class II malocclusion. Intergroup comparisons were performed using Student's t-tests and chi-square test with Yates' correction at a significance level of 5 per cent. Bionator appliance was effective in generating differential growth between the jaws. Cephalometric skeletal measurements ANB, WITS, Lafh, Co-A and dental L6-Mp, U1.Pp, IsIi, OB, OJ showed statistically significantly different from the control. Bionator induced more dentoalveolar changes than skeletal during treatment in prepubertal stage.

Este estudo quantificou as alterações esqueléticas e dentoalveolares no período pré-puberal de crescimento após o tratamento da má oclusão de classe II, divisão 1 com bionator. Quarenta pacientes classe II foram divididos em dois grupos. Um grupo com 20 pacientes tratados consecutivamente com bionator. A média de idade no início do tratamento (T0) foi de 9,1 anos, enquanto ao final (T1) foi de 10,6 anos. O tempo médio de tratamento foi de 17,7 meses. Os dados cefalométricos antes e após o tratamento foram avaliados e comparados com um grupo controle de 20 pacientes com má oclusão de classe II, divisão 1 não tratada. A comparação intergrupo foi realizada pelo teste t de Student e teste qui-quadrado com correção de Yates para um nível de significância de 5 por cento. O aparelho foi efetivo em gerar diferencial de crescimento entre os arcos dentários. As medidas cefalométricas esqueléticas ANB, WITS, Lafh, Co-A e as dentárias L6-Mp, U1.Pp, IsIi, OB, OJ demonstraram diferença estatística significante entre os grupos. O bionator induziu maiores alterações dentoalveolares que esqueléticas no tratamento da classe II, divisão 1 durante o período pré-puberal.

Changes in alveolar bone support induced by the Herbst appliance: a tomographic evaluation.

OBJECTIVE: This study evaluated alveolar bone loss around mandibular incisors, induced by the Herbst appliance. METHODS: The sample consisted of 23 patients (11 men, 12 women; mean age of 15.76 ± 1.75 years), Class II, Division 1 malocclusion, treated with the Herbst appliance. CBCT scans were obtained before treatment (T0) and after Herbst treatment (T1). Vertical alveolar bone level and alveolar bone thickness of mandibular incisors were assessed. Buccal (B), lingual (L) and total (T) bone thicknesses were assessed at crestal (1), midroot (2) and apical (3) levels of mandibular incisors. Student's t-test and Wilcoxon t-test were used to compare dependent samples in parametric and nonparametric cases, respectively. Pearson's and Spearman's rank correlation analyses were performed to determine the relationship of changes in alveolar bone thickness. Results were considered at a significance level of 5%. RESULTS: Mandibular incisors showed no statistical significance for vertical alveolar bone level. Alveolar bone thickness of mandibular incisors significantly reduced after treatment at B1, B2, B3, T1 and significantly increased at L2. The magnitude of the statistically significant changes was less than 0.2 mm. The changes in alveolar bone thickness showed no statistical significance with incisor inclination degree. CONCLUSIONS: CBCT scans showed an association between the Herbst appliance and alveolar bone loss on the buccal surface of mandibular incisors; however, without clinical significance.

Changes in alveolar bone support induced by the Herbst appliance: a tomographic evaluation

ABSTRACT Objective: This study evaluated alveolar bone loss around mandibular incisors, induced by the Herbst appliance. Methods: The sample consisted of 23 patients (11 men, 12 women; mean age of 15.76 ± 1.75 years), Class II, Division 1 malocclusion, treated with the Herbst appliance. CBCT scans were obtained before treatment (T0) and after Herbst treatment (T1). Vertical alveolar bone level and alveolar bone thickness of mandibular incisors were assessed. Buccal (B), lingual (L) and total (T) bone thicknesses were assessed at crestal (1), midroot (2) and apical (3) levels of mandibular incisors. Student's t-test and Wilcoxon t-test were used to compare dependent samples in parametric and nonparametric cases, respectively. Pearson's and Spearman's rank correlation analyses were performed to determine the relationship of changes in alveolar bone thickness. Results were considered at a significance level of 5%. Results: Mandibular incisors showed no statistical significance for vertical alveolar bone level. Alveolar bone thickness of mandibular incisors significantly reduced after treatment at B1, B2, B3, T1 and significantly increased at L2. The magnitude of the statistically significant changes was less than 0.2 mm. The changes in alveolar bone thickness showed no statistical significance with incisor inclination degree. Conclusions: CBCT scans showed an association between the Herbst appliance and alveolar bone loss on the buccal surface of mandibular incisors; however, without clinical significance.

RESUMO Introdução: este estudo avaliou a perda óssea alveolar ao redor dos incisivos inferiores induzida pelo aparelho de Herbst. Métodos: a amostra foi composta por 23 pacientes (11 homens e 12 mulheres; média de idade 15,76 ± 1,75 anos), má oclusão de Classe II, divisão 1, tratados com aparelho de Herbst. TCFCs foram realizadas antes do tratamento (T0) e após o tratamento (T1) com o Herbst. A altura e a espessura óssea alveolar dos incisivos inferiores foram avaliadas. As espessuras ósseas vestibular (V), lingual (L) e total (T) foram mensuradas nos terços cervical (1), médio (2) e apical (3) dos incisivos inferiores. O teste t de Student e o teste t de Wilcoxon compararam as amostras dependentes nos casos paramétricos e não paramétricos, respectivamente. As análises de Pearson e Spearman determinaram a correlação entre as alterações na espessura do osso alveolar. Os resultados foram considerados para um nível de significância de 5%. Resultados: os incisivos inferiores não apresentaram significância estatística para a altura óssea alveolar. Após o tratamento, a espessura óssea alveolar dos incisivos inferiores reduziu-se significativamente em V1, V2, V3 e T1 e aumentou significativamente em L2. A quantidade da alteração óssea significativa foi menor que 0,2mm. As alterações na espessura óssea alveolar não apresentam correlação estatisticamente significativa com o grau de inclinação do incisivo. Conclusões: as imagens de TCFC demonstram associação entre o uso do aparelho de Herbst e a perda óssea alveolar no lado vestibular dos incisivos inferiores; entretanto, sem significância clínica.

Cone beam computed tomography study of apical root resorption induced by Herbst appliance.

OBJECTIVE: This study evaluated the frequency of root resorption during the orthodontic treatment with Herbst appliance by Cone Beam Computed Tomography (CBCT). MATERIAL AND METHODS: The sample comprised 23 patients (11 men, 12 women; mean ages 15.76±1.75 years) with Class II division 1 malocclusion, treated with Herbst appliance. CBCT was obtained before treatment (T0) and after Herbst treatment (T1). All the dental roots, except third molars, were evaluated, and apical root resorption was determined using the axial guided navigation method. Paired t-tests and Wilcoxon T Test were used to compare the dependent samples in parametric and nonparametric cases, respectively. Chi-Square Test with Yates' correction was used to evaluate the relationship between apical root resorption and gender. Results were considered at a significance level of 5%. RESULTS: Apical resorption was detected by CBCT in 57.96% of 980 roots that underwent Herbst appliance treatment. All patients had minimal resorption and there was no statistical significance between the genders. CONCLUSION: CBCT three-dimensional evaluation showed association between Herbst appliance and minimal apical root resorption, mostly in the anchoring teeth, without clinical significance.

Cone beam computed tomography study of apical root resorption induced by Herbst appliance

Objective This study evaluated the frequency of root resorption during the orthodontic treatment with Herbst appliance by Cone Beam Computed Tomography (CBCT).Material and Methods The sample comprised 23 patients (11 men, 12 women; mean ages 15.76±1.75 years) with Class II division 1 malocclusion, treated with Herbst appliance. CBCT was obtained before treatment (T0) and after Herbst treatment (T1). All the dental roots, except third molars, were evaluated, and apical root resorption was determined using the axial guided navigation method. Paired t-tests and Wilcoxon T Test were used to compare the dependent samples in parametric and nonparametric cases, respectively. Chi-Square Test with Yates’ correction was used to evaluate the relationship between apical root resorption and gender. Results were considered at a significance level of 5%.Results Apical resorption was detected by CBCT in 57.96% of 980 roots that underwent Herbst appliance treatment. All patients had minimal resorption and there was no statistical significance between the genders.Conclusion CBCT three-dimensional evaluation showed association between Herbst appliance and minimal apical root resorption, mostly in the anchoring teeth, without clinical significance.

Alterações cefalométricas dentárias induzidas pelo aparelho de Herbst com dois tipos de ancoragem para maxila / Cephalometric changes induced by the Herbst appliance with two types of maxillary Anchorage

O presente estudo avaliou se o tipo de ancoragem maxilar utilizada no aparelho de Herbst tem influência nos efeitos dentários induzidos pelo seu uso no tratamento da Classe II. Neste estudo retrospectivo, foram avaliadas telerradiografias de 44 pacientes em fase de crescimento com má oclusão Classe II Divisão 1ª e deficiência mandibular, submetidos ao tratamento com aparelho de Herbst. A amostra foi dividida em dois grupos de acordo com a ancoragem maxilar utilizada: dentossuportada (Grupo 1) e dentomucossuportada (Grupo 2). Em ambos os grupos, para cada indivíduo, foram obtidas duas telerradiografias: T1 ao início do tratamento e T2 ao final da fase ortopédica de tratamento. Para avaliação dos resultados foram usadas as abordagens descritiva e dedutiva. A análise exploratória dos dados foi feita através do cálculo de medidas e a análise inferencial através do teste não paramétrico de Mann-Whitney com nível de significância de 5%. Os resultados evidenciaram diferenças estatisticamente significantes para as medidas 1.NB, 1-NB, 1/.Pp, IMPA, linha vertical de referência – molar superior (LVR-M6s), linha horizontal de referência – molar superior (LHR-M6s) e linha vertical de referência – incisal do incisivo inferior (LVR-Iii). O Grupo 1, com ancoragem maxilar reduzida, apresentou distalização e intrusão dos molares superiores, menor efeito de verticalização dos incisivos superiores e menor efeito de vestibularização dos incisivos inferiores, enquanto que o Grupo 2, com ancoragem maxilar total, apresentou extrusão do molar superior, maior verticalização dos incisivos superiores e maior vestibularização dos incisivos inferiores. Os dois grupos apresentaram efeito similar de mesialização dos molares inferiores...

This study aimed at verifying if the type of jaw anchorage used in Herbst appliance interferes over dental effects induced by the use of the device in the treatment of Class II. The presennt retrospective study analyzed lateral cephalograms of 44 prepubertal Caucasian patients, both genders, with Class II division 1 and mandibular deficiency, submitted to orthodontic treatment using Herbst appliance. The sample was divided into two groups according to the type of jaw anchorage: tooth-supported (Group 1) and tooth-tissue-supported (Group 2). In both groups, for each subject, two lateral cephalograms at maximum intercuspation were obtained: T1 at the beginning of treatment and T2 at the end of treatment. To evaluate the results descriptive and deductive approaches were utilized. Exploratory analysis of data was performed by calculating summary statistics and inferential analysis using the nonparametric Mann-Whitney test with significance level of 5%. The results showed statistically significant differences for measures 1.NB, 1-NB, 1/.Pp, IMPA, vertical reference line – upper-molar (LVR-M6s), horizontal reference line – upper-molar (LHR-M6s), and vertical reference line – lower incisor incisal (LVR - Iii). Group 1, with low jaw anchorage, presented distalization and intrusion of upper molars, lower effect of verticalization of the upper incisors and lower effect of proclination of the lower incisors. The second group, with total jaw anchorage, presented extrusion of upper molars, and showed higher verticalization of the upper incisors and higher proclination of the lower incisors. Both groups showed similar effect of mesial movement of mandibular molars...

Extração seriada: considerações clínicas / Serial extraction: clinical considerations

O tratamento “precoce” das más-oclusões tem despertado interesse crescente da comunidade ortodôntica. Dentre estes, destaca-se a extração seriada que visa conciliar as diferenças entre a quantidade conhecida do material dentário e a deficiência permanente do osso de suporte. A técnica é aplicada na dentadura mista, por meio de uma sequência pré-determinada de exodontias entre dentes decíduos e permanentes, na busca do alinhamento imediato, de preferência espontâneo, dos dentes permanentes remanescentes com uma terapia ortodôntica mecânica mínima. Será relatado um caso clínico no qual foi realizada a extração seriada em um paciente com má-oclusão de Classe I, em crescimento, com apinhamento severo e biprotruso. Todos os objetivos estéticos e funcionais foram alcançados...

The early malocclusion treatment has increased interest of orthodontic community. Among these is the serial extraction that harmonizes the differences between the amount of dental material and permanent deficiency of supporting bone. The technique is applied in mixed dentition through a predetermined sequence of extractions between deciduous and permanent teeth, in order to reach spontaneous immediately alignment of remaining permanent teeth with a minimum orthodontic mechanics. It will be reported a case where the serial extraction was performed in a growing patient with biprotrusion, Class I malocclusion and severe crowding. All functional and aesthetics goals were reached...

Estudo em telerradiografia em norma de 45° no tratamento da Classe II com aparelho de Herbst / Oblique 45-degree radiograph study on the treatment of Class II with Herbst appliance

O objetivo deste estudo cefalométrico retrospectivo foi avaliar alterações mandibulares e maxilares induzidas pelo uso do aparelho de Herbst decorrentes do crescimento natural por meio de telerradiografias cefalométricas em norma de 45° de indivíduos com má oclusão de Classe II divisão 1 de Angle com retrusão mandibular. Uma amostra de 49 indivíduos com idade entre 8 a 10 anos, ou seja, antes do pico de crescimento pubertário com má oclusão Classe II divisão 1 foi utilizada, sendo dividida em 2 grupos: grupo tratado com o aparelho de Herbst (n=24) e grupo controle (n=25). O grupo controle foi pareado ao grupo tratado quanto ao gênero e idades ósseas e cronológicas. A análise estatística foi realizada por meio do teste t de Student. O aparelho de Herbst promoveu a correção da má oclusão em um período de 7 meses, por meio de mesialização dos primeiros molares permanentes inferiores e distalização dos primeiros molares permanentes superiores. O aparelho de Herbst não foi influente na estrutura mandibular, como também no comprimento efetivo da mandíbula. Concluiu-se que o tratamento precoce da Classe II utilizando o aparelho de Herbst corrigiu a relação anteroposterior predominantemente por modificações dentoalveolares.

The aim of this retrospective study was to evaluate mandibular and maxillary changes induced by the use of Herbst applianceand by natural growth through oblique cephalometric radiographs in children with Class II division 1 malocclusion with mandibular retrusion. A sample of 49 individuals with age ranging from 8 to 10 years old (before growth peak) with Class II division 1, were into two groups: Herbst treated group (n=24) and control group (n=25). Both groups were paired for gender and chronological age. Statistical analysis was performed through Student’s t test. The Herbst appliance promoted the Class II correction in a 7 months period by mesialization of lower permanent first molars and distalization of upper permanent first molars. The Herbst appliance had no influence over the mandibular structure or the mandibular length. It was concluded that early treatment with Herbst appliance corrected the Class II malocclusion by means of dentoalveolar changes.

Infra-oclusão de molares decíduos - diagnóstico e tratamento / Infraoccluded deciduos molars - diagnosis and treatment

A infra-oclusão dos molares decíduos é definida pela ausência total ou parcial do ligamento periodontal e caracteriza-se pela fusão anatômica do cemento e/ou dentina com o osso alveolar. Este trabalho tem o objetivo de relatar as implicações clínicas e opções de conduta do tratamento da anquilose em dentes decíduos por meio da apresentação de um caso clínico.

Infraocclusion of deciduous molars is defined by total or partial periodontal ligament absence and characterized by the cementum or dentin anatomical fusion with alveolar bone. This study aims to report an ankylosis clinical case, the implications and treatments management options in the deciduos dentition.

Aparelho Herbst X osteotomia sagital mandibular bilateral no tratamento do Padrão II, Classe II, divisão 1 em adultos - relato de casos / Herbst appliance X mandibular sagittal split osteotomy in adult Class II, division 1 treatment - case reports

Indivíduos adultos de Padrão II com deficiência mandibular e má oclusão de Classe II, divisão 1 possuem duas opções de tratamento: preparo ortodôntico com vistas à cirurgia de avanço mandibular ou aparelhos protratores mandibulares. O objetivo deste estudo foi analisar os efeitos de duas modalidades terapêuticas no tratamento da má oclusão de Classe II com deficiência mandibular. Dois indivíduos distintos com má oclusão de Classe II, divisão 1 e deficiência mandibular sagital foram tratados após o surto de crescimento. O primeiro indivíduo utilizou o aparelho Herbst como opção terapêutica e o outro foi tratado com osteotomia mandibular sagital bilateral. Foram avaliados os resultados cefalométricos, oclusão e face desses indivíduos. A correção da Classe II para uma oclusão normal tratada com sobressaliência horizontal e vertical corretas ocorreu tanto no caso tratado com aparelho Herbst quanto no associado à cirurgia de avanço mandibular. Assim, conclui-se que o aparelho Herbst pode ser uma alternativa para correção da má oclusão em casos limítrofes do Padrão II deficiência mandibular, Classe II, divisão 1, em adultos.

Two treatment options are available for adult patients with skeletal Class II malocclusion caused by mandibular deficiency: combined mandibular advancement surgery and orthodontic treatment or mandibular advancement appliance. This study aimed to analyze the effects of two therapeutic modalities of Class II malocclusion treatment with mandibular deficiency. Two distinct individuals with Class II malocclusion division 1 and mandibular deficiency were treated after growth spurt. The first individual used the Herbst appliance as a therapeutic option and the second individual was treated with bilateral sagittal osteotomy. The cephalometric, occlusion and face results were evaluated for both individuals. Correction of Class II malocclusion was observed on both Herbst and surgery patients resulting on a normal occlusal relationship with normal overjet and overbite. Therefore it was concluded that Herbst appliance can be used to treat borderline skeletal Class II in adult patients.

Avaliação do índice de irregularidade de Little em indivíduos que utilizaram o aparelho ortopédico funcional T4K / Assessment of Little’s irregularity index in individuals treated with functional appliance T4k

O objetivo desse estudo foi avaliar o grau de correção do apinhamento dentário na região anteroinferior de pacientes tratados com o aparelho funcional T4K (Trainer for Kids). Para isto, aplicou-se o índice de irregularidade de Little. Foram selecionados 20 pacientes leucodermas, sendo 10 indivíduos do gênero feminino e 10 do masculino, má oclusão Classe I e II de Angle, com idade cronológica de 5,7 a 11 anos, apresentando dentadura mista. O tratamento teve duração de 1 ano e 11 meses a 3 anos e 11 meses. As mensurações foram realizadas nos modelos de estudo obtidos antes e após o tratamento ortopédico funcional, com o auxílio de um paquímetro digital calibrado em mm, colocado paralelo ao plano oclusal. Também foram realizadas as medidas da sobressaliência e sobremordida com o auxílio de uma régua milimetrada. Os resultados demonstraram que o tratamento produziu uma diminuição significativa da sobressaliência (média 1,55 mm) e correção do apinhamento (média 1,23 mm). Na sobremordida, o aumento não foi significante. Não foi detectada qualquer relação das variáveis estudadas com o tempo de tratamento ou com a idade do paciente no início do tratamento. O tratamento com o aparelho T4k apresentou diminuição e melhora da sobressaliência e do apinhamento dentário.

The study aimed to assess the degree of dental crowding correction on the lower anterior region of patients treated with T4k functional appliance using Little’s irregularity index. Twenty caucasian patients of both gender (10 female and 10 male) were selected. They featured malocclusion Class I and II in mixed dentition, with chronological age between 5.7 and 11 years. The treatment lasted from 1 year and 11 months up to 3 years and 11 months. Lower anterior crowding was measured using Little’s irregularity index. Measurements were obtained on study models achieved before and after functional orthopedic therapy, using a digital caliper in millimeters and placed parallel to the occlusal plane. Overjet and overbite measurements were also performed using a caliper. Results demonstrated that the therapy provided significant decrease in overjet (average = 1.55 mm) and also in the irregularity index (average = 1.23 mm). There was a nonsignificant raise in overbite. There was no relation between the studied variables and the treatment period or even with the patient’s age in the beginning of the therapy. The treatment with T4k resulted on reduction and improvement of dental crowding.

Longitudinal study of mandibular behavior in Class I subjects with vertical and horizontal growth

OBJECTIVE: To evaluate possible differences in mandibular behavior in Class I individuals with vertical and horizontal growth patterns. METHODS: The sample consisted of 20 untreated Class I individuals divided into: Group 1 comprising 10 individuals with vertical growth pattern and Group 2 comprising 10 individuals with horizontal growth pattern, all of them belonging to the Burlington Growth Center files, University of Toronto-Canada, radiographically followed-up at ages 9, 12 and 21. Cephalometric radiographs, determined mean values for a long-term evaluation of mandibular behavior using the following measurements: SNB, Co-GN, SN.GoMe, anterior facial height and posterior facial height. RESULTS: SNB and Co-Gn values were higher in horizontal growth group at all of the ages studied; SN.GoMe measure was significantly lower in horizontal growth group; anterior facial height (AFH) showed lower values in individuals with horizontal growth pattern; and posterior facial height (PFH) showed lower values in individuals with vertical growth pattern. CONCLUSION: Long-term comparisons of Class I individuals' growth tendencies indicate that there are significant differences between both groups. Mandible showed a trend to clockwise rotation in Group 1. Group 2 showed a trend to brachycephalic facial form, due to the deficit in vertical development with regard to anterior facial height.

OBJETIVO: avaliar as possíveis diferenças no comportamento mandibular em indivíduos Classe I com crescimento vertical e horizontal. MÉTODOS: a amostra desse estudo consistiu de 20 indivíduos Classe I não tratados, sendo o grupo 1 composto por 10 indivíduos com padrão de crescimento vertical e o grupo 2 por 10 indivíduos com padrão de crescimento horizontal, pertencentes aos arquivos do Burlington Growth Center, University of Toronto, no Canadá, acompanhados radiograficamente nas idade de 9, 12 e 21 anos. Determinou-se, por meio de telerradiografias cefalométricas, em norma lateral, os valores médios para a avaliação longitudinal do comportamento da mandíbula utilizando as medidas SNB, Co-Gn, SN.GoMe, altura facial anterior e altura facial posterior. RESULTADOS: o valor de SNB e Co-Gn foram maiores no grupo com crescimento horizontal em todas as idades. A medida Sn.GoMe foi significativamente menor no grupo com crescimento horizontal, a altura facial anterior (AFH) apresentou valores menores nos indivíduos com padrão de crescimento horizontal, e a altura facial posterior (PFH) apresentou valores menores nos indivíduos com crescimento vertical. CONCLUSÃO: as comparações longitudinais das tendências de crescimento de indivíduos Classe I indicam que existe diferenças significativas entre os dois grupos. A mandíbula apresentou tendência à rotação horária no grupo 1. O grupo 2 exibiu tendência à característica de indivíduos braquicefálicos, na forma facial, devido ao déficit no desenvolvimento vertical na altura facial anterior.

Cephalometric evaluation of skeletal alterations induced by Herbst appliance during mixed dentition

OBJECTIVE: The present prospective clinical study was designed in order to evaluate horizontal and vertical skeletal alterations induced by the use of Herbst appliance in individuals with Class II, division 1 malocclusion during mixed dentition stage. METHODS: The sampling consisted of 15 pre-pubertal individuals (12 boys and 3 girls; initial age 9 years and 6 months), who were treated with Herbst appliance for a period of 7 months. The effects of the treatment were compared to a group of 15 individuals with Class II, division 1 malocclusion (8 boys and 7 girls, initial age averaged 9 years and 1 month), orthodontically untreated, who were followed up for a period of 12 months. Statistical analysis was performed with Student's t-test with significance level at 5%. RESULTS: It was showed that the treatment with Herbst appliance in mixed dentition stage has restricted maxilla growth. Mandibular and palatal planes have not undergone significant alteration; however, anterior and posterior facial heights have increased significantly. Facial convexity and maxillomandibular relationship were altered positively. Mandible has positioned significantly forward and its effective length increased 2.5 times more than the increase observed in control group. CONCLUSION: It was possible to conclude that Herbst appliance was able to provide satisfactory results in individuals during mixed dentition stage.

Efeitos do aparelho de Herbst no tratamento precoce da má oclusão. Classe II de Angle / Effects of Herbst appliance in early treatment of angle Class II malocclusion

A Classe II de Angle tem sido amplamente pesquisada por diversos autores devido à grande incidência na população, juntamente os meios para o seu tratamento. Dentre os métodos de tratamento, destaca-se o aparelho de Herbst que foi reintroduzido a mais de 3 décadas na comunidade ortodôntica. Por ser um aparelho que independe da cooperação do paciente e por propiciar uma ação contínua através de tubos telescópicos bilaterais, tornou-se atualmente o aparelho mais utilizado. O objetivo deste trabalho é demonstrar o tratamento precoce da má oclusão de Classe II divisão 1ª com retrusão mandibular com o uso do aparelho de Herbst.

Due to its high prevalence in general population, Angle Class II malocclusion has been widely studied by several authors, as well as the methods for its treatment. Among the possible treatment methods stands out the Herbst appliance. Reintroduced more than three decades ago in the orthodontics community, it became the most utilized appliance because it does not require patient compliance, and provides continued action through bilateral telescopic tubes. The objective of the present article was to demonstrate the early treatment of Class II Division 1 malocclusion with mandibular retrusion using Herbst appliance.

Herbst esplinte metálico fundido: novo modelo de confecção com Duralay

A má oclusão de Classe II é originária de vários fatores etiológicos e uma das características mais comum desta má oclusão é a retrusão mandibular3, por esse motivo, os aparelhos de avanço mandibular são eleitos para o tratamento e correção desta má oclusão. Um destes aparelhos é o Herbst, que apresenta várias formas de ancoragens na sua confecção10. Tradicionalmente, as bandas eram o sistema de ancoragem mais usado, no entanto, pela alta frequência de quebras as mesmas foram substituídas por esplinte metálico12. Esse aparelho quando confeccionado de cromo cobalto pelo método da prótese parcial removível, apresenta como desvantagens a quantidade de passos laboratoriais e a possível contração do metal, podendo ocasionar a má adaptação da estrutura metálica à boca do paciente. Dessa forma, este artigo apresenta um novo método de confecção do aparelho de Herbst esplinte metálico fundido com uso da Duralay e liga níquel cromo. Esse método diminui os passos laboratoriais, proporciona maior resistência à tração e minimiza a contração da estrutura metálica, pois a resina química Duralay proporciona menor expansão do que a cera2