Temporomandibular joint disc position and shape in patients submitted to two protocols of rapid maxillary expansion and face mask therapy: A randomized clinical trial.

OBJECTIVE: The objective of this prospective study was to assess possible changes in the position and shape of the temporomandibular joint (TMJ) articular disc in patients treated with two protocols of rapid maxillary expansion (RME) and face mask (FM) therapy. METHODS: A sample of 88 patients with Class III or Class III subdivision malocclusions, aged between 6 and 13 years, were consecutively selected and divided into three groups (G): G1-34 patients were treated with RME, followed by FM therapy; G2-34 patients were treated using RME according to modified alternate rapid maxillary expansion and constriction (ALT-RAMEC) protocol, followed by FM therapy. These treated groups were randomly (1:1 allocation ratio) distributed according to the two treatment protocols. G3 - Control Group - 20 untreated patients were followed. Magnetic resonance imaging (MRI) TMJs were obtained before (T1) and after (T2) a treatment period or follow-up. McNemar test, Fisher's exact test and intra- and inter-observer concordance (K) were performed (p ≤ .05). RESULTS: There were no statistically significant differences in the baseline cephalometric variables at T1 between the groups. There were statistically significant differences between the groups (p < .001) in relation to the disc shape in T1, since G1 (8 TMJs -11.76%) presented higher occurrences of altered forms in comparison with G2 (no changes). No significant differences were observed in disc position CM and OM (G1 - p > .999; G2 - p = .063; G3 - p = .500) and shape (G1 - p > 0.999; G2 - p = .250; G3 - not calculable), between T1 × T2, in any of the groups studied. CONCLUSION: The two treatment protocols did not have adverse effects on the position and shape of the TMJ disc, in a short-term evaluation.

Associations between skeletal discrepancies, breathing pattern, and upper airway obstruction in Class III malocclusions.

OBJECTIVE: To verify the associations between sagittal and vertical skeletal discrepancies, changes in upper airways, and breathing pattern in children and adolescents with Angle Class III and Class III subdivision malocclusions. METHODS: Eighty-five children and adolescents with a mean age of 9.5 ± 1.74 years were selected. Cephalometry assessed the sagittal relationship (AO-BO measurement), facial types (Ricketts VERT index), nasopharynx, and oropharynx. An otorhinolaryngologist analyzed the breathing pattern and upper airway obstruction during anamnesis, physical examination, anterior rhinoscopy, and nasofibroscopy. Medical records were also reviewed. For statistical analysis, ordinary one-way ANOVA, Kruskal-Wallis (Tukey's post-hoc), unpaired t-test, Pearson's correlation, chi-square, and Fisher's exact tests (p < 0.05) were used. RESULTS: The nasopharyngeal cephalometric dimension and pharyngeal tonsil hypertrophy were associated, whereas the oropharyngeal cephalometric dimension and palatine tonsils hypertrophy were not. Sagittal discrepancies were associated with septum deviation, while facial type was associated with inferior turbinate and palatine tonsils hypertrophy. However, facial type was not associated with breathing pattern, septum deviation, and pharyngeal tonsils hypertrophy. CONCLUSIONS: Sagittal discrepancies and type of malocclusion were not associated with breathing pattern and changes in upper airways, except for the severity of septum deviation and Class III malocclusions, which were associated with large sagittal discrepancies. Although the facial types analyzed presented signs of airway obstruction, the highest prevalence of inferior turbinate and palatine tonsils hypertrophy were found in patients with dolichofacial type.

Temporomandibular joint articular disc position and shape in skeletal Class III.

OBJECTIVE: To compare the position and shape of the temporomandibular joint (TMJ) articular disc among the sagittal and vertical skeletal patterns in Angle Class III, Class III subdivision malocclusion and normal occlusion. The null hypothesis was that there was no difference in disc position and shape in different (1) malocclusions and (2) skeletal patterns. METHODS: This cross-sectional observational study evaluated 105 patients divided into 3 groups: Class III (33, 9.39 ± 1.96 years), Class III subdivision (45, 9.51 ± 1.59 years) and a normal occlusion (27, 10.24 ± 0.87 years) was included as healthy control. Severity of the maxilla-mandibular anteroposterior discrepancy and vertical facial pattern were determined using 2D cephalometry, and the position and shape of the articular discs were evaluated in magnetic resonance images. Statistical parametric and non-parametric tests and Kappa analysis for intra-observer and inter-observer assessment were used (p ≤ .05). RESULTS: Significant between-group differences were found in articular disc position. In the normal occlusion group, all the articular discs were well positioned. In Class III and Class III subdivision, the discs were displaced in 30.3% and 12.2% of the TMJs, respectively. Sagittal and vertical skeletal patterns did not affect the findings significantly. The Class III subdivision malocclusion group is probably different from the other groups, showing 97.7% of biconcave discs in both TMJs. CONCLUSION: The longitudinal follow-up of this sample becomes relevant as the two groups with malocclusion in the pre-peak phase of pubertal growth showed differences in the prevalence of displacement and form of the articular disc, with no association with their vertical facial characteristics.

Class II malocclusion associated with mandibular deficiency and maxillary and mandibular crowding: follow-up evaluation eight years after treatment completion.

This report describes the correction of a clinical case of malocclusion with anteroposterior discrepancy and transverse, sagittal and vertical deficiencies. A nonextraction technique was used to preserve space in the dental arches and control facial growth for the correction of the sagittal skeletal relationship and of overbite. The mechanics adopted efficiently corrected malocclusion: all functional and esthetic goals were achieved, and results remained stable eight years after treatment completion. This case was presented to the Committee of the Brazilian Board of Orthodontics and Facial Orthopedics (BBO) as part of the requirements necessary to obtain the BBO Diploma.

Class II malocclusion associated with mandibular deficiency and maxillary and mandibular crowding: follow-up evaluation eight years after treatment completion

ABSTRACT This report describes the correction of a clinical case of malocclusion with anteroposterior discrepancy and transverse, sagittal and vertical deficiencies. A nonextraction technique was used to preserve space in the dental arches and control facial growth for the correction of the sagittal skeletal relationship and of overbite. The mechanics adopted efficiently corrected malocclusion: all functional and esthetic goals were achieved, and results remained stable eight years after treatment completion. This case was presented to the Committee of the Brazilian Board of Orthodontics and Facial Orthopedics (BBO) as part of the requirements necessary to obtain the BBO Diploma.

RESUMO O caso clínico apresentado descreve a correção de uma má oclusão com discrepância negativa e deficiências nos sentidos transversal, sagital e vertical. A mecânica de Cetlin foi utilizada visando à obtenção de espaços nas arcadas dentárias e o controle do crescimento facial, otimizando, assim, a correção sagital das bases ósseas e adequando o trespasse vertical. Essa mecânica foi eficiente na correção da má oclusão, atingindo todas as metas funcionais e estéticas, que continuaram estáveis oito anos após a conclusão do tratamento. 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.

Dental and skeletal changes in patients with mandibular retrognathism following treatment with Herbst and pre-adjusted fixed appliance

OBJECTIVE: To assess the dentoskeletal changes observed in treatment of Class II, division 1 malocclusion patients with mandibular retrognathism. Treatment was performed with the Herbst orthopedic appliance during 13 months (phase I) and pre-adjusted orthodontic fixed appliance (phase II). METHODS: Lateral cephalograms of 17 adolescents were taken in phase I onset (T1) and completion (T2); in the first thirteen months of phase II (T3) and in phase II completion (T4). Differences among the cephalometric variables were statistically analyzed (Bonferroni variance and multiple comparisons). RESULTS: From T1 to T4, 42% of overall maxillary growth was observed between T1 and T2 (P < 0.01), 40.3% between T2 and T3 (P < 0.05) and 17.7% between T3 and T4 (n.s.). As for overall mandibular movement, 48.2% was observed between T1 and T2 (P < 0.001) and 51.8% between T2 and T4 (P < 0.01) of which 15.1% was observed between T2 and T3 (n.s.) and 36.7% between T3 and T4 (P < 0.01). Class II molar relationship and overjet were properly corrected. The occlusal plane which rotated clockwise between T1 and T2, returned to its initial position between T2 and T3 remaining stable until T4. The mandibular plane inclination did not change at any time during treatment. CONCLUSION: Mandibular growth was significantly greater in comparison to maxillary, allowing sagittal maxillomandibular adjustment. The dentoalveolar changes (upper molar) that overcorrected the malocclusion in phase I, partially recurred in phase II, but did not hinder correction of the malocclusion. Facial type was preserved. .

OBJETIVO: avaliar as alterações dentoesqueléticas observadas no tratamento da má oclusão de Classe II com retrognatismo mandibular, realizado com aparelho ortopédico de Herbst durante 13 meses (Fase I) e aparelho ortodôntico fixo pré-ajustado (Fase II). MÉTODOS: foram obtidas telerradiografias laterais de 17 adolescentes, ao início (T1), final da Fase I (T2), primeiros 13 meses da Fase II (T3) e término da Fase II (T4). As diferenças entre as variáveis cefalométricas foram analisadas estatisticamente (variância e comparações múltiplas de Bonferroni). RESULTADOS: de T1 a T4, do total da projeção da maxila, 42% foram observados de T1 a T2 (p < 0,01); 40,3% de T2 a T3 (p < 0,05); e 17,7% de T3 a T4 (n.s.). Do total da projeção da mandíbula, foi notado 48,2% de T1 a T2 (p < 0,001) e 51,8% de T2 a T4 (p < 0,01), sendo 15,1% (n.s.) de T2 a T3, e 36,7% de T3 a T4 (p < 0,01). A relação molar e a sobressaliência foram corrigidas idealmente. Em T4, todos apresentavam características de oclusão normal. O plano oclusal que de T1 a T2 rotacionou no sentido horário, de T2 a T3 retornou aos valores iniciais, mantendo-se estável até T4. A inclinação do plano mandibular, responsável pela caracterização do tipo facial, não alterou em nenhum tempo. CONCLUSÃO: a mandíbula cresceu significativamente mais que a maxila, favorecendo o ajuste sagital maxilomandibular. As mudanças dentárias (molares superiores), que sobrecorrigiram a má oclusão na Fase I, recidivaram parcialmente na Fase II, sem comprometer a correção da má oclusão. O tipo facial foi preservado. .

Morphological changes of condyles and Helkimo clinical dysfunction index in patients treated with Herbst--orthodontic appliance.

This study evaluated the morphological changes in the temporomandibular joint (TMJ) condyles and calculated the Helkimo clinical dysfunction index (CDI) in adolescents with Class II Division 1 malocclusion and mandibular retrognathism treated with the Herbst appliance (phase I) and fixed orthodontic appliances (phase II). Thirty-two consecutive adolescents underwent phase I, and 23 completed phase II. The TMJs were evaluated qualitatively using magnetic resonance imaging (MRI) at the beginning of treatment (T1), during phase I (T2), at the end of phase I (T3) and at the end of phase II (T4). The CDI was calculated at T1, T3 and T4. From T1 to T3 (p=0.326), there were no changes in condyle morphology in 86.0% of the TMJs. From T3 to T4 (p<0.05) and T1 to T4 (p<0.05), changes occurred in 39.1% and 43.4% of the condyles. No significant changes in CDI occurred from T1 to T3, T3 to T4 and T1 to T4 (p=1.000; 86.6%, 76.2% and 76.2% concordance). After phase I, there were practically no changes in condyle morphology. At the end of phase II, a mild flattening was observed in some condyles. It may be concluded that no significant changes occurred in CDI after both treatment phases.

Morphological Changes of Condyles and Helkimo Clinical Dysfunction Index in Patients Treated with Herbst - Orthodontic Appliance

This study evaluated the morphological changes in the temporomandibular joint (TMJ) condyles and calculated the Helkimo clinical dysfunction index (CDI) in adolescents with Class II Division 1 malocclusion and mandibular retrognathism treated with the Herbst appliance (phase I) and fixed orthodontic appliances (phase II). Thirty-two consecutive adolescents underwent phase I, and 23 completed phase II. The TMJs were evaluated qualitatively using magnetic resonance imaging (MRI) at the beginning of treatment (T1), during phase I (T2), at the end of phase I (T3) and at the end of phase II (T4). The CDI was calculated at T1, T3 and T4. From T1 to T3 (p=0.326), there were no changes in condyle morphology in 86.0% of the TMJs. From T3 to T4 (p<0.05) and T1 to T4 (p<0.05), changes occurred in 39.1% and 43.4% of the condyles. No significant changes in CDI occurred from T1 to T3, T3 to T4 and T1 to T4 (p=1.000; 86.6%, 76.2% and 76.2% concordance). After phase I, there were practically no changes in condyle morphology. At the end of phase II, a mild flattening was observed in some condyles. It may be concluded that no significant changes occurred in CDI after both treatment phases.

Este estudo avaliou as mudanças morfológicas nas cabeças da mandíbula das articulações temporo mandibulares (ATMs) e calculou o índex de disfunção clínico de Helkimo (IDC) em adolescentes com má oclusão de Classe II Divisão1 e retrognatismo mandibular, tratados com aparelho de Herbst (fase I) e aparelho ortodôntico fixo (fase II). Trinta e dois adolescentes consecutivos passaram pela fase I e 23 completaram a fase II. As ATMs foram avaliadas qualitativamente por meio de imagem da resonância magnética (IRM) ao início do tratamento (T1), durante a fase I (T2), no final da fase I (T3) e no final da fase II (T4). O IDC foi calculado em T1, T3 e T4. De T1 a T3 (p=0,326) não ocorreram mudanças na morfologia da cabeça da mandíbula em 86,0% das ATMs. De T3 a T4 (p<0,05) e T1 a T4 (p<0,05) ocorreram mudanças em 39,1% e 43,4% das cabeças das mandíbulas. Não ocorreram mudanças significantes no IDC de T1 a T3, T3 a T4 e T1 a T4 (p=1,000; 86,6%, 76,2% e 76,2% concordância). Após a fase I, não houve praticamente mudanças na morfologia da cabeça da mandíbula. Ao final da fase II, um leve aplainamento foi observado em algumas cabeças das mandíbulas. Pode ser concluído que não ocorreram mudanças significantes no IDC após ambas as fases de tratamento.

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.

Estudo comparativo cefalométrico dos padrões dentofaciais de indivíduos portadores de oclusão normal e de más oclusões de Angle / Comparative cephalometric study of dentofacial patterns of individuals with normal occlusion and Angle malocclusions

OBJETIVO: avaliar os padrões dentofaciais de pacientes portadores de oclusão normal e más oclusões de Angle quanto a possíveis diferenças entre as grandezas estudadas, em relação ao sexo, dentro de cada grupo e entre os grupos. MÉTODOS: a amostra constou de 200 telerradiografias cefalométricas laterais obtidas de jovens brasileiros, de ambos os sexos, na faixa etária de 11 anos e 2 meses a 19 anos e 10 meses, apresentando dentição permanente. O material foi dividido, quanto ao tipo de oclusão, em cinco grupos: um de pacientes portadores de oclusão normal, e quatro de pacientes portadores de más oclusões de Angle, sendo cada grupo dividido igualmente quanto ao sexo. Foram avaliadas grandezas cefalométricas angulares e lineares. RESULTADOS: na grande maioria das grandezas, os sexos masculino e feminino não diferiram; entre os grupos, a posição da maxila não mostrou diferença significativa, o retrognatismo mandibular foi marcante nos grupos de Classe II divisões 1ª e 2ª e foram observados alguns desequilíbrios verticais com diferenças significativas; o padrão foi hipodivergente para os grupos de oclusão normal e Classe II, divisão 2ª, e neutro para os grupos de Classe I; Classe II, divisão 1ª; e Classe III; a compensação dentoalveolar foi evidente nos grupos de Classe III e de Classe II, divisão 2ª; o grupo de oclusão normal apresentou perfil mais convexo que os padrões americanos. CONCLUSÃO: foi possível configurar, de forma geral, algumas características da morfologia facial para alguns tipos de más oclusões. Entretanto, existe a necessidade de avaliar a face individualmente, pois algumas características permeiam entre os diferentes tipos de oclusão.

OBJECTIVE: To evaluate dentofacial patterns of patients with normal occlusion and Angle malocclusions, examining potential differences between specific cephalometric measures as they relate to gender, both intra- and intergroup.METHODS: The sample consisted of 200 lateral cephalometric radiographs obtained from young Brazilians of both genders, aged between 11 years and 2 months and 19 years and 10 months, with permanent dentition. The material was divided according to the type of occlusion into five groups: One group consisted of patients with normal occlusion and four groups of patients with Angle malocclusions, and each group was also divided by gender. Angular and linear cephalometric measures were evaluated.RESULTS: Genders did not differ in most measures. Position of the maxilla showed no significant differences between groups. Mandibular retrognathia was remarkable in groups with Class II, Divisions 1 and 2. Vertical imbalances were observed with some significant differences. The pattern was found to be hypodivergent for groups with normal occlusion and Class II, Division 2, and neutral for groups with Class I; Class II, Division 1 and Class III. Dentoalveolar compensation was evident in groups with Class III and Class II, Division 2. Finally, the normal occlusion group profile was more convex than the patterns found in the US population.CONCLUSIONS: In general, some features of facial morphology were associated with certain types of malocclusion. However, individual assessment of each face is still necessary as some of the features are shared across different types of occlusion.

Changes in temporomandibular joint disc position and form following Herbst and fixed orthodontic treatment.

OBJECTIVE: To determine the changes in the position and form of the temporomandibular joint articular disc in adolescents with Class II division 1 malocclusion and mandibular retrognathism treated with the Herbst appliance (phase I) and fixed orthodontic appliance (phase II). MATERIALS AND METHODS: Thirty-two consecutive adolescents went through phase I of treatment and 23 completed phase II. The temporomandibular joints were evaluated qualitatively by means of magnetic resonance images at the beginning of treatment (T1), during phase I (T2), at the end of phase I (T3), and at the end of phase II (T4). RESULTS: Significant changes in disc position were not observed with the mouth closed between T1 x T3 (P = .317), T3 x T4 (P = .287), or T1 x T4 (P = .261). At T2, on average, the disc was positioned regressively. With the mouth open, no difference was observed between T1 x T3 (P = .223) or T1 x T4 (P = .082). We did observe a significant difference between T3 x T4 (P < .05). Significant changes in the disc form were found with the mouth closed between T1 x T2 (P < .001) and T2 x T3 (P < .001). CONCLUSIONS: At the end of the two-phase treatment, in general terms, the position and form of the initial articular discs were maintained; however, in some temporomandibular joints some seemingly adverse effects were observed at T4.

Tratamento ortopédico com aparelho de Herbst: ocorrem mudanças verticais no padrão de crescimento facial / Orthopedic treatment with the Herbst appliance: do vertical changes occur in the facial growth pattern

OBJETIVO: o objetivo deste estudo prospectivo de 32 adolescentes com má oclusão de Classe II, divisão 1, associada a retrognatismo mandibular, tratados com aparelho de Herbst, construído sobre bandas e coroas metálicas, foi avaliar cefalometricamente as possíveis mudanças no padrão de crescimento facial. METODOLOGIA: as telerradiografias laterais foram obtidas ao início do tratamento (T1) e imediatamente após 12 meses de tratamento com o referido aparelho ortopédico (T2). Foram utilizados o quociente de Jarabak e o VERT de Ricketts (modificado) para determinação do padrão facial em T1 e T2. RESULTADOS: utilizando o quociente de Jarabak, os resultados evidenciaram que 27 casos (84,4 por cento) apresentaram padrões hipodivergentes em T1 e permaneceram da mesma forma em T2. Cinco casos (15,6 por cento) apresentaram padrão neutro em T1 e não exibiram mudanças em T2. Quando avaliado o VERT de Ricketts (modificado), não ocorreram mudanças no padrão facial em 31 pacientes. Em apenas um caso ocorreu mudança do tipo facial. CONCLUSÃO: baseado nos resultados obtidos, pode-se concluir que, após 12 meses de tratamento com aparelho de Herbst, não ocorreram mudanças verticais no padrão de crescimento facial dos pacientes estudados.

OBJECTIVE: The aim of this prospective study was to evaluate through the exam of cephalograms the occurrence of changes in facial growth pattern. The sample was composed by 32 adolescent with Angle Class II, division 1 malocclusion and mandibular retrognathism. All patients were treated with the Herbst appliance built over bands and metal crowns. METHODOLOGY: Lateral cephalograms were taken at the beginning of treatment (T1) and immediately after 12 months of treatment with Herbst appliance (T2). Jarabak's coefficient and Ricketts' VERT (modified) were used to establish the facial pattern in T1 and T2. RESULTS: According to Jarabak's coefficient, in T1, 84.4 percent (27 cases) presented hypodiverging pattern and 15.6 percent (5 cases) presented neutral pattern. The facial growth pattern was maintained in all patients from T1 to T2. When the (modified) Ricketts' VERT was used, 31 patients showed the same growth pattern from T1 to T2. Only one patient exhibited a different pattern. CONCLUSION: Based on the results it can be concluded that, after 12 months of treatment with the Herbst appliance, there were no vertical changes in the facial growth pattern of the studied subjects.

Avaliação longitudinal das ATMs com ressonância magnética em adolescente tratado com aparelho de Herbst e ortodontia fixa / TMJs longitudinal assessment by means of magnetic resonance of a adolescent trated with Herbst appliance and fixed Orthodontics

O objetivo do presente artigo clínico foi avaliar, por meio de imagens de ressonância magnética (IRMs), os efeitos nas articulações temporomandibulares (ATMs) provocados pelo tratamento, com aparelho de Herbst e aparelho fixo total, de uma má oclusão classe II, divisão 1, associada ao retrognatismo mandibular. As IRMs foram realizadas em cinco tempos: imediatamente antes da colocação do aparelho de Herbst (T1), dez semanas após a colocação do aparelho de Herbst (T2), após seis meses de tratamento com o aparelho de Herbst (T3), no final de 12 meses da terapia com Herbst (T4) e imediantamente após a remoção do aparelho ortodôntico fixo (T5). A avaliação qualitativa das IRMs mostrou, em T1, os côndilos e discos dentro dos padrões de normalidade. Em T2, devido ao avanço mandibular assimétrico ocasionado pelo aparelho de Herbst, os côndilos estavam fora da fossa mandibular, com maior evidência na ATM direita, e os discos articulares assumiram posição retrusiva. Em T3, os côndilos retornaram parcialmente para o interior da fossa mandibular, porém, ainda mantendo uma ligeira assimetria entre as ATMs direita e esquerda. Em T4 e T5, os côndilos e discos articulares ficaram dentro dos padrões fisiológicos. Em T2, as IRMss apresentaram, nas regiões posterossuperior dos côndilos e supradiscal, uma área com hipersinal, sugerindo acúmulo de líquido na região supradiscal e início de remodelação nos côndilos. Com base nos resultados obtidos, pôde-se concluir que, em uma avaliação a curto prazo, não ocorreram efeitos adversos nas ATMs após o tratamento com Herbst e aparelho ortodôntico fixo.

Effects of Herbst appliance treatment on temporomandibular joint disc position and morphology: a prospective magnetic resonance imaging study.

INTRODUCTION: The objective of this prospective study was to evaluate changes in the position and morphology of the disc in the temporomandibular joint (TMJ) with magnetic resonance imaging (MRI). METHODS: The subjects were 32 consecutive adolescent patients with Class II Division 1 malocclusion treated with the Herbst appliance. The MRIs were obtained immediately before treatment (T1), 8 to 10 weeks after appliance placement (T2), and 12 months later (T3). RESULTS: Qualitative evaluation of the MRIs showed that, in 42 (65.62%) of the 64 TMJs, the disc was positioned within normal limits at T1. Because of the advancements caused by the Herbst appliance, a tendency for disc retrusion was observed at T2, but at T3 the disc had returned to normal limits. In 22 TMJs (34.37%), the disc was displaced at T1, and no changes were observed at T3. In most subjects, comparison of the morphology of the disc at T1, T2, and, T3 showed no significant change. CONCLUSIONS: Herbst therapy does not cause adverse effects on the morphology and position of the articular disc in the short term.

Intervenção precoce na mordida aberta anterior / Early intervention in anterior open bite

A mordida aberta anterior é uma anomalia complexa cujas características próprias envolvem a função, a estética, além das alterações dentárias e esqueléticas. Sua principal característica é a presença de um trespasse vertical negativo, existente entre as bordas incisais dos dentes anteriores superiores e inferiores, quando a mandíbula está em posição cêntrica. O objetivo deste trabalho é apresentar, por meio de um relato clínico, a intervenção precoce de uma mordida aberta anterior funcional associada ao hábito de sucção da chupeta, que foi tratada com grade palatina na fase de dentição decídua. Os resultados clínicos demonstraram a viabilidade e a eficiência da realização de uma terapia, mesmo em crianças de pouca idade, em curto prazo de tempo.

The anterior open bite is a complex anomaly, with its own characteristics, such as aesthetic, function, as well as dental and skeletal changes. Its main characteristic is the presence of a negative vertical crossing existing between the incisor borders of the upper anterior and lower anterior teeth, when the jaw is in centric position. The objective of this study is to present, through a clinical case analysis, the precocious intervention of one anterior open bite case associated with the habit of the pacifier, that was dealt with palatal crib in the phase of primary dentition. The clinical results demonstrated the viability and efficiency of the therapy in young children in short term.

Herbst appliance therapy and temporomandibular joint disc position: a prospective longitudinal magnetic resonance imaging study.

INTRODUCTION: The objective of this prospective study was to verify changes in the position of the temporomandibular joint (TMJ) disc by means of magnetic resonance images (MRIs) in adolescent patients treated with the Herbst appliance. METHODS: Twenty consecutive Class II Division 1 patients treated with Herbst appliances were selected for the study. MRIs were analyzed at 3 stages: immediately before Herbst treatment (T1), 8 to 10 weeks after appliance placement (T2), and at the end of the 12-month Herbst treatment, immediately after appliance removal (T3). RESULTS: Class I or overcorrected Class I dental-arch relationships were observed after Herbst therapy. The qualitative evaluation showed that each patient had the disc within normal limits at T1. At T2, a slight tendency toward disc retrusion because of mandibular advancement was observed, but, at T3, the disc returned to normal, similar to T1 values. By using a quantitative evaluation, parasagittal MRIs (central, medial, and lateral slices) of the TMJs showed that there was no change of disc position from T1 to T3, except in the central slice, which had a retrusive position of the articular disc at T3. CONCLUSIONS: During the 12-month period of Herbst appliance treatment, mild changes in the position of the disc occurred in patients whose articular discs were within normal limits at T1. These changes were within normal physiological limits when evaluated in the short term.

Avaliação do espaço aéreo faríngeo em pacientes com retrognatismo mandibular tratados com aparelho Herbst / Evaluation of pharyngeal airway in patients with manidular retrognatism treated with Herbst apliance

O objetivo desse trabalho foi avaliar radiograficamente a mudança do espaço decorrente do uso do aparelho ortopédico de Herbst em adolescentes com retrognatismo mandibular. A amostra constou das telerradiografias em norma lateral referente a 22 pacientes (Idade média de 12 anos e 10 meses, Desvio padrão + - 0,94) e analisadas as diferenças do espaço aéreo posterior (EAP) e distância do osso hióide ao plano mandibular (H-Pm) nos tempos: inicial (T1), seis meses(T2)e um ano (T3) de tratamento com aparelho de Herbst. Os resultados mostraram que a grandeza cefalométrica EAP foi maior nos tempos T2 e T3, quando comparado ao tempo T1 (p< 0,001). A grandeza cefalométrica da distância do osso hióide ao plano mandibular (H-Pm) não mostrou diferença de valores nos diferentes tempos (p=0,985). Com base nos resultados podemos concluir, que embora não houvesse diferença na medida H-Pm o uso do aparelho de Herbest foi eficiente no aumento do espaço aéreo faríngeo posterior em pacientes com retrognatismo mandibular.

Ain of this study was to report radiographic change in pharyngeal upper airway with Herbst mandibular advancement device in adolescents with mandibular retrognastism. The sample was composed of cephalometric roentgenograms obtained in 22 patients (Mean age 12.89 +- 0.94 years) and evaluated the differences of posterior airway space (PAS) and hyoid bone to mandibular plane distance in times: preoperative (T1), six months (T2) and one year (T3) of treatment with Herbst appliance. Results showed that cephalometric measurements of the distance between the hyoid bone and the mandible (MP-H) don’t increase in different times (p=0,985). In these results our conclusion is that. Herbst appliance was efficient in increased pharyngeal upper airway in patients with mandibular retrognatism.

Avaliação por meio de ressonância magnética das mudanças da posição dos côndilos nas ATMs de adolescentes com retrognatismo mandibular tratados com aparelho de Herbst / Evaluation by means of magnetic resonance of the changes in the condyle position of TMJ's of adolescents with mandibular retrognatism and treated with the Herbst appliance

O objetivo deste estudo prospectivo foi avaliar a posição do côndilo das articulações temporomandibulares (ATMs), por meio da ressonância magnética (RM), em adolescentes portadores de maloclusão de classe II, divisão 1ª de Angle, associada a retrognatismo mandibular, tratados durante 12 meses com o aparelho ortopédico de Herbst. A amostra constou de 20 adolescentes brasileiros (40 ATMs), leucodermas, de ambos sexos (7 do sexo masculino e 13 do feminino), em fase de crescimento, com idade média de 12 anos e oito meses, desvio padrão de um ano e um mês e, ausência de deslocamento do disco articular. As imagens de RM foram adquiridas em três tempos do tratamento: T1 –antes do início, T2 – após oito semanas até 10 semanas da colocação do aparelho, e T3 –após 12 meses, no final do período de avaliação. Foi realizada uma avaliação qualitativa da posição do côndilo na fossa mandibular, com boca fechada (BF) e máxima intercuspição habitual (MIH). Na avaliação foi observado que 33(82,5%) côndilos de 40 ATMs estavam concêntricos (BF) e retroposicionados (MIH) em T1, ficaram anteriorizados (BF e MIH) em T2, retornando à posição original (BF e MIH) em T3. Em sete (17,5%) articulações o comportamento foi diferente, porém não caracterizando uma condição patológica. Com base nos resultados obtidos pode-se afirmar que este método de tratamento não alterou a posição do côndilo na fossa mandibular entre os tempos inicial e final do período de avaliação.

The purpose of this prospective study was to evaluate the condyle and the temporomandibular joint disk position (TMJ’s) by means of magnet resonance (MR), in adolescents with Class II, division 1 Angle malocclusion and mandibular retrognatism following Herbst treatment during twelve months. The sample was compoused by 20 white Brazilian adolescents (40 TMJ’s), from both sexes (seven male and 13 female individuals), average age of 12 years and eight months, standard deviation of one year and one month, and absence of articular disk displacement. The MR images were taken during three different stages of treatment: T1 – before the beginning of treatment, T2- between eight and 10 weeks after set-up, and T3- after 12 months, in the evaluation period. A qualitative evaluation of the condyle position in the mandibular fossa was carried out with closed mouth (CM) and in habitual maximum intercuspation (HMI). The results showed that 33 (82,5%) condyles of 40 TMJ’s presented concentric position (CM) and were retropositioned (HMI) at T1, displaced forward (CM and HMI) at T2 and returning to its original position (CM and HMI) at T3. In seven (17,5%) TMJ’s the behavior was different, but did not characterize a pathologic condition. Based an the results achieved, it can be conclude that this method of treatment has not changed the condyle position in the mandibular fossa between the initial and final stages of the evaluation period.

Dispositivos intrabucais fixos para correção da relação molar de Classe II / Fixed intraoral appliances for correction of Class II molar relationship

A correção da relação molar de Classe II é pratica comum na clínica ortodôntica, fazendo-se necessária a distalização dos molares superiores, acompanhada ou não de alterações ortopédicas. A partir dos anos 70, diversos autores começaram a desenvolver aparatologia capaz de conseguir a distalização dos molares em quantidades de movimento até então difíceis de serem conseguidas com a tração extrabucal, buscando a máxima eficiência no mínimo intervalo de tempo, com pouca ou nenhuma colaboração do paciente. O objetivo deste trabalho foi revisar dispositivos que são usados para correção da relação molar de Classe II, os quais fossem intrabucais, mais estéticos, e fixos, para diminuir a necessidade de colaboração do paciente durante o tratamento. Destes, destacaram-se os Magnetos, o Jasper Jumper, o Pêndulo de Hilgers, o Jones Jig e o Distal Jet