Developmental association of palatal dimensions and palatal rugae characteristics in Angle´s classes I, II and III of malocclusion / Asociación de desarrollo de las dimensiones palatinas y las características de las rugas palatinas en las clases I, II y III de maloclusión de Angle

During development, bony changes in the palate are reflected in the palatal rugae. Therefore, we hypothesized that the palatal dimensions (PD) influence the shape and number of palatal rugae (PR). The objectives were to record the palatal rugae characteristics (PRC) and palatal dimensions (intercanine distance (ICD), intermolar distance (IMD), palatal height (PH) and palatal area (PA) in Classes I, II and III malocclusion patients and investigate their interrelationship, and statistically examine the possibility of predicting PRC with the PD. Four hundred eighty-one pre-orthodontic study casts of healthy patients with normal palate anatomy were grouped as Classes I, II and III and scanned using 3D cast scanner. The PRC, ICD, IMD, PH, and PA were recorded digitally using 3D enabled software. The data was statistically analyzed. A strong statistically significant difference was observed between PA and number of straight and wavy rugae. ICD and the number of straight rugae were also related. A weak correlation exists between malocclusion classes and PA. The remaining rugae characteristics did not exhibit any relation with palatal dimensions. PA is positively related to the number of straight rugae and negatively related to the number of wavy rugae. Bigger palates have more straight rugae and less number of wavy rugae. A weak correlation between PA and Angle's class I malocclusion exists. We also propose that PA has a developmental association with the number and shape of PR.

Durante el desarrollo, los cambios óseos en el paladar se reflejan en las rugas palatinas. Por lo tanto, planteamos la hipótesis de que las dimensiones palatinas influyen en la forma y el número de las rugas palatinas. Los objetivos fueron registrar las características de las rugas palatinas y las dimensiones palatales (distancia intercanina, distancia intermolar, altura palatina y área palatina) en pacientes con maloclusión de clases I, II y III e investigar su interrelación, y examinar estadísticamente la posibilidad de predecir las características de las rugas palatinas con las dimensiones palatinas. Cuatrocientos ochenta y un estudios pre-ortodónticos de pacientes sanos con anatomía normal del paladar se agruparon como Clases I, II y III y se escanearon con un escáner de emisión 3D. La distancia intercanina, distancia inter molar, altura palatina y área palatina se registraron digitalmente utilizando el software 3D. Los datos se analizaron estadísticamente. Se observó una diferencia estadísticamente significativa entre la altura palatina y el número de rugas rectas y onduladas. Se registró también la distancia intercanina y el número de rugas rectas. Existe una correlación débil entre las clases de maloclusión y la altura palatina. Las características restantes de las rugas palatinas no mostraron ninguna relación con las dimensiones palatinas. El área palatina está relacionada positivamente con el número de rugas rectas y negativamente relacionada con el número de rugas onduladas. Los paladares más grandes tienen más rugas rectas y menor cantidad de rugas onduladas. Existe una correlación débil entre el área palatina y la clase I de maloclusión de Angle. También proponemos que el área palatina tiene una asociación de desarrollo con el número y la forma de rugas palatinas.

Palatal rugae characteristics and its relationship with Angle class 1, 2 & 3 malocclusions / Características de rugas palatinas y su relación con ángulos de maloclusiónes clase 1, 2 & 3

SUMMARY: The objectives of the study were to, 1. Compare the accuracy of four methods of acquisition of palatal rugae (PR) characteristics (PRC). 2. Study the predominant PRC in Angles Class 1, 2, and 3 malocclusions. 3. To statistically correlate the predominant PRC with Class 1, 2 & 3 malocclusions and thus explore the possibility of utilizing it in predicting malocclusions. Study casts and intraoral 3D scan images (3Shape® Intra-Oral Scanner) of the palate of 104 healthy orthodontic patients were included as Group I and Group II respectively. The casts of Group I were scanned using 3Shape® (Group III) and Sirona inEos X5® (Group IV) cast scanners. PRC for all groups were recorded and PRC of Group I was compared with PRC of Groups II, III and IV for possible matching. 3D images of Group IV were further divided according to Angles classification and predominant PRC analyzed. 97.8 % of PRC match was observed in Group I and Group IV. Wavy and complex rugae were predominant in Class 1 and 3 malocclusions and showed statistically significant difference between Class 1, 2 and 3 malocclusions (p=0.00 and 0.014 respectively) with wavy being higher in Class 1 and complex being higher in Class 3 (LSD Post Hoc analysis). Direct intraoral 3D scanning and 3D scanning of the palatal area of casts are equally reliable methods for PR acquisition for examining PRC. All PRC considered together have a minimal impact on prediction of malocclusions, however, influence of wavy characteristic was maximum.

RESUMEN: Los objetivos del estudio fueron los siguientes: 1. Comparar la precisión de cuatro métodos de adquisición de las características de la rugosidad palatina (CRP). 2. Estudiar las CRP predominantes en maloclusiones clases 1, 2 y 3. 3. Correlacionar estadísticamente las CRP predominantes con maloclusiones clase 1, 2 y 3 e investigar la posibilidad de utilizarlas en la predicción de maloclusiones. Se incluyeron en el Grupo I y en el Grupo II, los moldes de estudio y las imágenes de barrido 3D intraoral (3Shape® Intra-Oral Scanner) del paladar de 104 pacientes ortodónticos sanos. Los escaneos del Grupo I se escanearon utilizando escáner fundidos 3Shape® (Grupo III) y Sirona inEos X5® (Grupo IV). CRP para todos los grupos se registraron y CRP del Grupo I se comparó con las CRP de los Grupos II, III y IV para una posible coincidencia. Las imágenes 3D del Grupo IV se dividieron de acuerdo con la clasificación de ángulos y las CRP predominantes analizadas. Se observó un 97,8 % de concordancia en CRP en los grupos I y IV. Las rugas onduladas y complejas predominaron en las maloclusiones de Clases 1 y 3 y mostraron diferencias estadísticamente significativas entre las maloclusiones de Clases 1, 2 y 3 (p = 0,00 y 0,014 respectivamente), siendo el ondulado más alto en la Clase 1 y el complejo en la Clase 3 (LSD Post Hoc). El escaneo 3D intraoral directo y el escaneado 3D del área palatal son métodos igualmente confiables para la adquisición de CRP para el examen de las CRP. Todas las CRP consideradas en conjunto tienen algún grado de impacto en la predicción de las maloclusiones, sin embargo, fue mayor la influencia de la característica ondulada.

Cortical and cancellous bone in mandibular symphysis: implications in osteosynthesis and osteotomy / Hueso cortical y esponjoso en sínfisis mandibular: implicancias en osteotomía y osteosíntesis

The aim of this study was to quantify the presence of cortical and cancellous bone in the mandibular symphysis. A descriptive study was conducted using cone beam computed tomography where skeletal class I and class III subjects were included, defined according to characteristics detected on dental, clinical and dental occlusion x-rays. From the 3D reconstruction, sections were used in relation to the axial axis of the teeth of the anterior sector; the amount of buccal cortical, cortical, lingual, inferior cortical and cancellous bone as well as symphysis height were determined. The measurements were taken using routine methods and analyzed with ANOVA and Tukey's HSD test with p <0.05 for statistical significance. 20 skeletal class I subjects aged 23 years (± 4.5) and 20 class III subjects aged 22 years (± 5.2) were included. Symphysis height was significantly greater in skeletal class III subjects, exceeding by 0.8 mm the height of class I subjects; the buccal cortical bone presented on average 2 mm less at different dental levels, whereas the lingual cortical and inferior basal bones were significantly larger than the buccal cortical bone. The cancellous and cortical bones did not present any significant differences between the two groups (p=0.093). The buccal and basilar cortical bone is smaller than lingual cortical bone.

El objetivo fue determinar la presencia de hueso cortical y esponjoso en sínfisis mandibular. Se realizó un estudio descriptivo en tomografías computadorizadas cone beam donde se analizaron sujetos clase I y clase III esqueletal definidos según características dentales, clínicas y radiográficas de oclusión dental y características radiográficas. Desde la reconstrucción 3D se utilizaron cortes en relación al eje axial de los dientes del sector anterior; en ellos se determinó la cantidad de hueso cortical bucal, cortical, lingual, cortical inferior, hueso esponjoso y altura de sínfisis. Las mediciones fueron realizadas con métodos de rutina y fueron analizados con la prueba ANOVA y HDS Turkey considerando un valor de p <0.05 para considerar significancia estadística. 20 sujetos clase I esqueletal con 23 años (+ 4.5) y 20 sujetos clase III esqueletal con edad de 23 años (+ 4.5) fueron incluidos. La altura de sínfisis fue significativamente mayor en sujetos de clase III esqueletal, superando por 0.8 mm la altura de sujetos clase I; el hueso cortical bucal presento en promedio menor de 2 mm en diferentes niveles dentarios, mientras que la cortical lingual y basal inferior fueron significativamente mayor que la cortical bucal. El hueso esponjoso y hueso cortical no presentó diferencias significativas entre ambos grupos (p=0.093). La cortical bucal y basilar son menores que el hueso cortical lingual.

Comparison of arch forms between Turkish and North American

ABSTRACT Objective: The aim of this study was to clarify the morphological differences in the mandibular arches of Turkish and North American white subjects. Methods: The sample included 132 Turkish (34 Class I, 58 Class II, and 40 Class III) and 160 North American (60 Class I, 50 Class II, and 50 Class III) subjects. The most facial portion of 13 proximal contact areas was digitized from photocopied images of patients' mandibular dental arches. Clinical bracket points were calculated for each tooth based on mandibular tooth thickness data. Four linear and two proportional measurements were taken. The subjects were grouped according to arch form types (tapered, ovoid and square) in order to have frequency distribution compared between ethnic groups in each Angle classification. Results: The Turkish group showed significantly lower molar depth and more significant molar width-depth (W/D) ratio in all three Angle classifications. On the other hand, the Turkish group also showed a significantly larger intercanine width in Class III malocclusion and intermolar width in Class II malocclusion. The most frequent arch forms seen were the ovoid arch form in the Turkish group and the tapered form in the white group. Conclusions: Our results demonstrate that when treating Turkish patients, one should expect to use preformed ovoid arch form orthodontic wires in a significant percentage of patients.

RESUMO Objetivo: o objetivo deste estudo foi avaliar as diferenças morfológicas entre as arcadas dentárias inferiores de indivíduos turcos e indivíduos norte-americanos leucodermas. Métodos: a amostra incluiu 132 indivíduos turcos (34 Classe I, 58 Classe II e 40 Classe III) e 160 norte-americanos (60 Classe I, 50 Classe II e 50 Classe III). A porção mais vestibular de 13 áreas de contato proximal foi digitalizada a partir de imagens impressas das arcadas dentárias inferiores dos pacientes. Os pontos de colagem dos braquetes foram calculados, para cada dente, com base em dados referentes à espessura dos dentes inferiores. Quatro medidas lineares e duas proporcionais foram obtidas. Os indivíduos foram classificados de acordo com o formato da arcada (triangular, oval e quadrada), permitindo que a frequência de cada formato fosse comparada entre os grupos étnicos, e dentro de cada classificação de Angle. Resultados: o grupo composto por indivíduos turcos apresentou profundidade da arcada na região dos molares significativamente menor, além de uma proporção largura/profundidade da arcada na região dos molares maior em todas as classificações de Angle. Em contrapartida, esse mesmo grupo mostrou maiores distâncias intercaninos nos pacientes Classe III e intermolares nos pacientes Classe II. A arcada oval foi a mais frequente no grupo composto por indivíduos turcos, enquanto a arcada triangular foi a mais frequente no grupo composto por indivíduos norte-americanos leucodermas. Conclusões: os resultados obtidos mostram que, ao tratar pacientes turcos, o profissional deve prever o uso de arcos ortodônticos pré-conformados ovais em um percentual significativo dos pacientes.

Avaliação das alterações nas vias aéreas superiores através de tomografia computadorizada Cone-Beam em pacientes submetidos à cirurgia ortognática de avanço bimaxilar / Three-dimensional upper airway space changes after bimaxillary advancement by Cone-Beam Computed Tomography

Introdução: O descontentamento com a estética facial é considerado o fator motivador mais frequente na procura pela cirurgia ortognática, visto que este é o procedimento indicado nos casos de severas discrepâncias dentoesqueléticas em pacientes adultos. A anatomia das vias aéreas superiores (VAS) permite que fatores como obesidade, hipotonia muscular e deficiência mandibular favoreçam sua obstrução, podendo gerar a Apneia Obstrutiva do Sono (AOS), caracterizada por episódios recorrentes de obstrução parcial ou completa das VAS durante o sono. As cirurgias de avanço bimaxilar estão associadas ao aumento do espaço aéreo, no entanto, as alterações morfológicas e volumétricas ainda não são bem conhecidas. Objetivos: Avaliar as alterações em 3D do espaço aéreo faríngeo frente aos procedimentos de cirurgia ortognática de avanço bimaxilar em pacientes Classe I e II esqueléticos. Material e Métodos: A análise da área axial mínima e do volume da aérea superior foi realizada em pré-operatório (T0) e pós-operatório (T1) de 56 pacientes, sendo 21 do sexo masculino e 35 do sexo feminino, com média de idade de 35,8 (±10,7) anos, submetidos ao avanço bimaxilar pela técnica da osteotomia sagital de mandíbula bilateral associada ao avanço de maxila por meio de osteotomia Le Fort I. As avaliações foram feitas através de tomografia computadorizada Cone-beam, utilizando-se o Programa Dolphin Imaging 11.7. Foi utilizado o teste t pareado para comparar os dados pré e pós-operatórios. Todos os testes foram realizados com o programa Statistica, adotando-se um nível de significância de 5%. Resultados: No estudo do erro do método, não houve erro casual nem sistemático entre a primeira e a segunda medição das variáveis (p >0,05 em todas as medidas). A cirurgia de avanço bimaxilar apresentou uma média de 73,6% (± 74,75%) de aumento volumétrico e 113,5% (±123,87%) de aumento na área axial mínima. Conclusões: Podemos concluir que a cirurgia de avanço bimaxilar proporciona um aumento volumétrico significativo no espaço aéreo superior, bem como na área axial mínima, no entanto, esse ganho nem sempre ocorre na mesma magnitude para todos os pacientes.(AU)

Introduction: Facial aesthetics dissatisfaction is considered the most common motivating factor in the search for orthognathic surgery. This procedure may be used in cases of severe dental and skeletal discrepancies in adult patients. The restricted space anatomy of the upper airway space (UAS) allows features such as obesity, muscular hypotonia and mandibular deficiency favor clogging, which may lead to obstructive sleep apnea (OSA), characterized by recurrent episodes of partial or complete obstruction of the UAS during sleep. Surgeries of bimaxillary advancement are associated with increased UAS, however, the morphological and volumetric changes are not well known. Objectives: to evaluate changes in 3D pharyngeal airway in front of orthognathic surgery procedures of skeletal Class I and II subjects. Material and Methods: 3D pharyngeal airway was evaluated preoperative (T0) and postoperative (T1), with the aid of the analysis of the minimum axial area and airway volume. Fifty-six patients 21 male and 35 female, with a mean age of 35.8 (± 10.7) years undergo bimaxillary advancement by the technique of bilateral sagittal split osteotomy of the mandible associated with maxillary advancement through Le Fort I osteotomy. Measurements were made using Cone-beam Computed Tomography, using the Dolphin Imaging program 11.7. Paired t test was used to compare to the data between T0 and T1. All tests were performed with the Statistica Program, adopting a 5% significance level. Results: In the method error of the study, there was no casual or systematic error between the first and second measurement variables (p > 0.05 for all measures). The bimaxillary advancement surgery showed an average of 73.6% (± 74.75%) of increase in volume and 113.5% (±123.87%) increase in the minimum axial area. Conclusions: We concluded that the maxillomandibular advancement surgery provides a significant increase in volume in the UAS as well as the minimum axial area; however, this gain is not always in the same magnitude for all patients.(AU)

Tomographic evaluation of the temporomandibular joint in malocclusion subjects: condylar morphology and position

Abstract The aim of this study was to investigate condyle concentricity and morphology, and their association with Class I and II malocclusions (Angle). The sample consisted of 49 individuals of both genders, between 11 and 35 years old, divided into two groups, G1: 26 patients with Class I malocclusion, and G2: 23 patients with Class II malocclusion, selected for orthodontic treatment. Evaluation of the condyle morphology and position was performed by the same previously calibrated examiner using cone-beam computed tomography (CBCT) images of the subjects. The CBCT scans were analyzed by means of a 3D program (Dolphin 11.5, Dolphin Imaging & Management Solutions, Chatsworth, CA, USA), with a 25% level of sensitivity. The images obtained from the coronal slices were employed for the condyle morphology analysis, which classified the condyle form as rounded, as flat or convex, and as triangular or angled. The sagittal slices were used to classify further the condyles as concentric and displaced anteriorly or posteriorly. A clinical examination was also performed, including TMJ and muscle palpation. The kappa test was used to evaluate investigator calibration; the Chi-square and paired t-tests were used for analysis. The convex and anteriorly positioned condyles were found most frequently, regardless of the type of malocclusion. No association was observed between the groups regarding condylar characteristics.

The use of three-dimensional cephalometric references in dentoskeletal symmetry diagnosis

OBJECTIVE: The aim of this study is to assess dentoskeletal symmetry in cone-beam computed tomography (CBCT) scans of Brazilian individuals with Angle Class I malocclusion. MATERIAL: A total of 47 patients (22 females and 25 males) aged between 11 and 16 years old (14 years) seen in a private radiology service (CIRO, Goiânia, GO, Brazil) were assessed. All CBCT scans were obtained from January, 2009 to December, 2010. Cephalometric measurements were taken by multiplanar reconstruction (axial, coronal and sagittal) using Vista Dent3DPro 2.0 (Dentsply GAC, New York, USA). Minimum, maximum, mean and standard deviation values were arranged in tables, and Student t-test was used to determine statistical significance (P < 0.05). RESULTS: Data were homogeneous, and differences between the right and left sides were not significant. CONCLUSIONS: Cephalometric measurements of Brazilian individuals with Angle Class I malocclusion can be used to establish facial symmetry and three-dimensional standard references which might be useful for orthodontic and surgical planning. .

OBJETIVO: o objetivo deste estudo é avaliar a simetria dentoesqueléticas em imagens de tomografia computadorizada de feixe cônico (TCFC) de indivíduos brasileiros com má oclusão Classe I de Angle. MÉTODOS: quarenta e sete pacientes (22 meninas e 25 meninos), com idades entre 11 e 16 anos (14 anos, em média), foram atendidos em um serviço de radiologia privado. Todas as imagens de TCFC foram adquiridas a partir de janeiro de 2009 a dezembro de 2010. Medições cefalométricas foram realizadas por reconstruções multiplanares (axial, coronal e sagital) usando o VistaDent 3D Pro 2.0 ( Dentsply GAC, Nova Iorque, EUA). O desvio-padrão mínimo, máximo e a média foram descritos em tabelas, e o teste t de Student foi utilizado para definir significância estatística (p < 0,05). RESULTADOS: os dados foram homogêneos e as diferenças entre os lados direito e esquerdo não foram significativas. CONCLUSÕES: as medidas cefalométricas de indivíduos brasileiros com má oclusão Classe I de Angle podem ser usadas para definir a simetria facial e referências de padrão tridimensional, que podem ser úteis para o planejamento ortodôntico e cirúrgico. .

Class I malocclusion with severe double rotrusion treated with first premolars extraction

Angle Class I malocclusion with bimaxillary protrusion is characterized by severe buccal tipping of incisors, which causes upper and lower lip protrusion. First premolars extraction is recommended to reduce facial convexity as a result of anterior teeth retraction, which keeps canines and first molars in key to occlusion. In order to yield orthodontic results that are compatible with ideal esthetic and cephalometric outcomes, the space closure phase needs to be carried out with overbite and incisors torque control. The majority of cases also requires maximum anchorage of posterior teeth. This case was presented to the Brazilian Board of Orthodontics and Facial Orthopedics (BBO) as a requirement for the title of certified by the BBO.

A má oclusão de Classe I de Angle com biprotrusão é caracterizada pela inclinação acentuada dos incisivos para vestibular, o que provoca a protrusão dos lábios superior e inferior. As extrações dos primeiros pré-molares têm sido indicadas para reduzir a convexidade facial com a retração dos dentes anteriores, mantendo a relação de chave de oclusão dos caninos e dos primeiros molares. Para a obtenção de resultados compatíveis com as metas estéticas e cefalométricas idealizadas para o tratamento ortodôntico, é necessário que a fase de fechamento de espaços seja realizada com controle da sobremordida e do torque dos incisivos. Na maioria dos casos, também há necessidade de se proporcionar ancoragem máxima aos dentes posteriores. O presente caso clínico foi apresentado à Diretoria do Board Brasileiro de Ortodontia e Ortopedia Facial (BBO) como parte dos requisitos para a obtenção do título de Diplomado pelo BBO.

Intercanine and intermolar widths in angle class I, II and III malocclusions

Malrelation along the transverse plane is one of the most common causes of malocclusion and can be assessed by considering the intercanine and intermolar widths. An endeavour was undertaken to find the intercanine and intermolar widths on 76 dental casts of the individuals having Class I, Class II division 1, Class II division 2, Class III and Class II subdivision malocclusions, visiting orthodontic department of Sardar Begum dental college and hospital, Peshawar. Results were obtained using SPSS version 20 which showed the mean maxillary intermolar widths of 34.6mm*, 34.5mm, 30.9mm, 34.7 mm and 34.18mm for Class I, Class II division 1,Class II division 2,Class III and Class II subdi-vision groups respectively. Mean maxillary intercanine widths were found to be 24.16mm, 24.5mm, 24.6mm, 23.9mm and 23.05mm for Class I, Class II division 1,Class II division 2,Class III and Class II subdivision groups respectively. Similarly mean mandibular intermolar widths were 32.8mm, 33.02mm, 30.3mm, 33.1mm and 32.8mm for Class I, Class II division 1, Class II division 2, Class III and Class II subdivision groups respectively. While mean mandibular intercanine widths were found to be 19.2mm,19.06mm,20.34mm,19.54mm and 18.75mm for the Class I, Class II division 1,Class II division 2,Class III and Class II subdivision groups respectively. ANOVA analysis showed no sta-tistical significant differences in the intermolar and intercanine widths among the five malocclusion groups

Evaluation of the vertical alterations of the upper second molars after the alignment and leveling phase using the MBT technique

OBJECTIVE: This study aimed at comparing the distocervical angulations of upper second molars crowns of groups with normal occlusion and with Angle Class I and II malocclusions. Additionally, it aimed to analyze the changes occurring after alignment and leveling performed with MBT technique. METHODS: The sample of normal occlusions comprised 32 lateral teleradiographs, while the sample of malocclusions comprised 38 initial and post-leveling lateral teleradiographs. RESULTS: The results did not show statistically significant differences between morphological characteristics of the normal occlusion group and the malocclusion group. On the other hand, after alignment and leveling, statistically significant reduction was observed in distocervical inclinations with extrusion of the distal portion of upper second molars.

OBJETIVO: a proposta do presente trabalho foi comparar as angulações distocervicais das coroas dos segundos molares superiores de um grupo com oclusão normal e outro composto de más oclusões de Classes I e II de Angle, e analisar as modificações ocorridas após o alinhamento e nivelamento com a técnica MBT. MÉTODOS: a amostra de oclusão normal foi composta por 32 telerradiografias laterais; e a amostra de má oclusão constituiu-se de 38 telerradiografias laterais iniciais e pós-nivelamento. RESULTADOS: os resultados não mostraram diferença estatisticamente significativa entre as características morfológicas dos grupos com oclusão normal e com má oclusão; porém, após o alinhamento e nivelamento, observamos redução estatisticamente significativa nas inclinações distocervicais, com extrusão da porção distal dos segundos molares superiores.

Assessing the predictability of ANB, 1-NB, P-NB and 1-NA measurements on Steiner cephalometric analysis

OBJECTIVE: To evaluate, in the initial and final stages of corrective orthodontic treatment, the predictability of the ANB, 1-NB, PNB and 1-NA during case individualization, which considers the characteristics of the patient, professional experience and the mechanics to be used. METHODS: Ninety patients were selected at the State University of Londrina (UEL, Brazil), presenting Angle Class I and II malocclusions, treated with and without extraction of four premolars and divided into three groups: Horizontal, balanced and vertical. The cephalometric variables were evaluated in the initial, prognosis and final stages of treatment in order to observe the behavior of the estimates, or how they were higher or lower than the values obtained. RESULTS: It was noticed the influence of the facial pattern on the behavior of the measures examined, the values proposed for the ANB were statistically different from values obtained at the end of the treatment; in the vertical group the final value was the one that most approached the proposed value; regarding 1-NB the values proposed with the Steiner analysis for the balanced and vertical groups were not achieved. For P-NB, there was no difference between genders. For 1-NA it was observed that the values obtained at the end of treatment differ from estimates in the three groups. CONCLUSIONS: The limitations of the estimates of the measures do not invalidate its clinical or teaching use, if aware of its deficiencies, the analysis can be used with restrictions.

OBJETIVO: avaliar, nas fases inicial e final de tratamento ortodôntico corretivo, a previsibilidade das medidas ANB, 1-NB, P-NB, e 1-NA durante a individualização dos casos, onde se consideram as características inerentes do paciente, bem como a experiência do profissional e a mecânica a ser utilizada. MÉTODOS: foram selecionados 90 pacientes, tratados na UEL, apresentando Classes I e II de Angle, tratados com e sem extrações de quatro pré-molares e divididos em três grupos: horizontal, equilibrado e vertical. As grandezas cefalométricas foram avaliadas nas fases inicial, proposta e final de tratamento, com o intuito de observar o comportamento das estimativas, ou seja, o quanto elas foram maiores ou menores que os valores obtidos. RESULTADOS: constatou-se influência do padrão facial no comportamento das medidas analisadas; os valores propostos para o ANB foram estatisticamente diferentes dos valores obtidos ao final do tratamento; no grupo vertical, o valor final foi o que mais se aproximou do valor proposto; em relação à medida 1-NB, os valores propostos durante a elaboração da análise de Steiner para os grupos equilibrado e vertical não foram alcançados. Para medida PNB, não se observou diferença entre os sexos. Na medida 1-NA, foi observado que os valores obtidos ao final do tratamento diferem das estimativas nos três grupos analisados. CONCLUSÃO: as limitações das estimativas das medidas não invalidam seu emprego clínico ou didático, desde que, conscientes de suas deficiências, sejam utilizadas com restrições.

Dental arch widths in class I normal occlusion and class II division 1 malocclusion

The purpose of this study was to compare dental arch widths Class II division 1 malocclusion with normal Class I occlusion subjects. The Intercanine, Interpremolar and intermolar widths were measured on 100 dental casts [50 class I and 50 class II/1 malocclusion subjects]. The data was developed on SPSS 16 for windows. Independent-samples t-test was applied for comparison of the groups. Lower Intercanine width was larger in class II/1 malocclusion and Intermolar width was significantly increased in call I normal occlusion group. Interpremolar width between the two groups did not reveal any significant difference. Lower intercanine width was significantly larger in class II/1 and Maxillary intermolar width was significantly narrower in class II/1 malocclusion subjects

Masseter muscle thickness in different skeletal morphology: An ultrasonographic study.

Background: The thickness of the masseter muscle during relaxation and contraction states was measured by ultrasonography. Subjects were classified according to their sagittal skeletal relationships. The association between muscle thickness and facial morphology was studied. Context: Masseter muscle thickness influences the skeletal patterns. Aim: To measure and compare the thickness of the masseter muscle in individuals with skeletal class I occlusion and skeletal class II malocclusions and to correlate its relationship with craniofacial morphology. Settings and Design: The study was conducted in a hospital setup and was designed to study the thickness of the masseter muscle in different skeletal morphologies. Materials and Methods: Seventy two individuals between the ages of 18 and 25 years were divided into Group I, Group IIA and Group IIB according to their skeletal relationships. Masseter muscle thickness was measured by ultrasonography. Eight linear and six angular cephalometric measurements were assessed. Statistical Analysis Used: Analysis of variance and Pearson's correlation analysis. Results: There was a statistically significant difference in muscle thickness between subjects of different skeletal patterns. Significant positive correlation between masseter muscle thickness and posterior total face height, jarabak ratio, ramus height, mandibular length and significant negative correlations with mandibular plane angle, gonial angle and PP-MP angle were observed. Conclusion: This study indicates the strong association between the masseter muscle and skeletal morphology.

Non-invasive 3D facial analysis and surface electromyography during functional pre-orthodontic therapy: a preliminary report

OBJECTIVES: Functional orthodontic devices can modify oral function thus permitting more adequate growth processes. The assessment of their effects should include both facial morphology and muscle function. This preliminary study investigated whether a preformed functional orthodontic device could induce variations in facial morphology and function along with correction of oral dysfunction in a group of orthodontic patients in the mixed and early permanent dentitions. MATERIAL AND METHODS: The three-dimensional coordinates of 50 facial landmarks (forehead, eyes, nose, cheeks, mouth, jaw and ears) were collected in 10 orthodontic male patients aged 8-13 years, and in 89 healthy reference boys of the same age. Soft tissue facial angles, distances, and ratios were computed. Surface electromyography of the masseter and temporalis muscles was performed, and standardized symmetry, muscular torque and activity were calculated. Soft-tissue facial modifications were analyzed non-invasively before and after a 6-month treatment with a functional device. Comparisons were made with z-scores and paired Student's t-tests. RESULTS: The 6-month treatment stimulated mandibular growth in the anterior and inferior directions, with significant variations in three-dimensional facial divergence and facial convexity. The modifications were larger in the patients than in reference children. In several occasions, the discrepancies relative to the norm became not significant after treatment. No significant variations in standardized muscular activity were found. CONCLUSIONS: Preliminary results showed that the continuous and correct use of the functional device induced measurable intraoral (dental arches) and extraoral (face) morphological modifications. The device did not modify the functional equilibrium of the masticatory muscles.

[Evaluation of condylar height and width in patients with class I and class III Malocclusions using panoramic and lateral cephalogram]

Situation of the condyle in glenoid fossa has a direct effect on the anteroposterior or vertical position of the mandible. Therefore, condylar situation and its shape has a special significance on producing facial morphology. The aim of this study was to evaluate the condylar height and width in patients with class III and class I malocclusion by using panoramic radiographs and lateral cephalograms. This study was performed on 80 pretreatment lateral cephalograms and panoramic films. Mean age in girls was 11 years and 4 months and in boys, it was 12 years and 2 months. Condylar characteristics were surveyed from the point of condylar width and condylar height. Condylar height was surveyed on the panoramic film. Condylar width was analyzed on the lateral cephalograms. Data were analyzed using t.test and ANOVA. Patients with class I malocclusion had a significantly longer condylar width relative to the patients with class III malocclusion. The condylar height in class III malocclusions was longer than class I malocclusion. This study revealed that in patients with class III malocclusion, condylar height was longer but condylar width was smaller than class I malocclusion

Avaliação cefalométrica da perda de ancoragem inferior, em pacientes meso e dólicofaciais tratados com a técnica straight-wire e extração de pré-molares / A cephalometric evaluation of the lower lost of anchorage in meso and dolicofacial patients, treated with the extraction of premolars in the straight-wire technique

Este estudo avaliou a perda de ancoragem inferior no tratamento ortodôntico com a técnica Straight-Wire, prescrição Roth, em pacientes com padrões meso e dólicofaciais que apresnetavam má oclusão de classe I de Angle. Utilizou-se uma amostra de 150 telerradiografias em norma lateral, nas estapas inicial, fional de nivelamento e final de tratamento, obtidas de 50 pacientes, com média de idade de 13 anos e 6 meses, tratados com extração dos primeiros pré-molares superiores e inferiores. Foi utulizado como acessório de ancoragem inferior o arco lingual. Embasado na análise e discussão dos resultados, concluiu-se que: 1) quanto ao posicionamento do incisivo inferior, os pacientes dólicofaciais tiveram maior moviemnto lingual com maior intensidade da fase final de nivelamento para final de tratamento; 2) quanto ao posicionamento da raiz do incisivo inferior, no grupo de pacientes dólicofaciais as variações foram mais expressivas, significando que neste padrão facuial ocorreu maior movimentação da raiz dos incisivos inferiores para linguaus; 3) não houve diferença estatisticamente significante entre os padrões faciais quanto ao posicionamento ântero-posterior do primeiro molar inferior; e 4) quanto ao posicionamento axial do primeiro molar inferior, nos pacientes dólicofaciuais apresentaram-se com significante inclinação da raiz para mesial e da coroa para distal

Avaliaçäo da recidiva da sobremordida profunda: estudo longitudinal cefalométrico e de modelos / Evaluation of the relapse of the deep overbite: cephalometric longitudinal study and of models

A recidiva da sobremordida profunda apresenta-se, ainda, como uma incógnita. As divergências de opiniöes suscitadas pela literatura decorrem das diferentes metodologias, incluindo os materiais e os métodos, como também, dos diversos componentes envolvidos em sua etiologia. Revisando a literatura pertinente, os fatores que provavelmente encontram-se envolvidos com esta recidiva säo: o padräo de crescimento facial, as alturas faciais anteriores e posteriores, a altura do ramo ascendente e o comprimento do corpo da mandíbula, o ângulo goníaco, o ângulo interincisivos, a recidiva do apinhamento ântero-inferior e da sobressaliência, além da movimentaçäo dos incisivos e dos molares. Dentro deste contexto, propôs-se avaliar a recidiva desta má oclusäo observando-se os fatores relatados acima. Para a composiçäo da amostra, selecionaram-se 48 jovens, leucodermas, de ambos os sexos, que apresentavam, inicialmente, Classe I e Classe II, 1ª divisäo, com sobremordida de no mínimo 3,5mm, tratados com extraçöes dos quatro primeiros pré-molares. As tomadas radiográficas e os modelos de estudo foram obtidos em 3 fases: ao início, ao final e 5 anos após o tratamento ortodôntico. Os resultados permitiram concluir que os fatores dentários correlacionados com a recidiva da sobremordida profunda foram a sobressaliência, a movimentaçäo dos incisivos e dos molares e o ângulo interincisivos. Para os fatores esqueléticos, somente apresentou correlaçäo estatisticamente significante a variável N-Me (altura facial anterior total). Verificou-se, também, uma forte correlaçäo da quantidade de correçäo com a quantidade de recidiva

Recidiva do apinhamento ântero-inferior em pacientes tratados ortodonticamente, com extraçöes dos 1§ pré-molares, 5 e 10 anos pós-contençäo: estudo cefalométrico e de modelos / Relapse of the lower anterior crowding in patients orthodontically treated, with first premolar extractions, 5 and 10 years post-retention: cephalometric study and of models

Realizou-se um estudo cefalométrico e em modelos, objetivando avaliar se há uma correlaçäo da recidiva do apinhamento ântero-inferior com as distâncias intercaninos, intermolares, o comprimento do arco, e os valores cefalométricos referentes às bases ósseas (NAP, WITS, SNA, SNB, ANB e SND), ao padräo do esqueleto cefálico (ABS, ABI, FMA, SN.Oclusal, SN.GoGn e SN.Gn) e ao posicionamento dos incisivos inferiores 1.NB, 1-NB, Linha I e IMPA). A amostra constitui-se dos modelos inferiores e telerradiografias em norma lateral de 33 pacientes, sendo 24 do sexo feminino e 9 do masculino, com más oclusöes de classe I (14 casos) e classe II, 1ª divisäo (19 casos), tratados ortodonticamente, pela técnica do Arco de Canto Simplificada, com extraçöes dos primeiros pré-molares superiores e inferiores...