Métodos de evaluación de la Dimensión Vertical Oclusal / Methods of evaluation of the Occlusal Vertical Dimension

RESUMEN: Antecedentes: La evaluación de la Dimensión Vertical Oclusal, es una fase importante en el diagnóstico y planificación del tratamiento que determina las relaciones estéticas y funcionales entre los maxilares. Objetivo: Conocer los métodos que ayuden a determinarla, ventajas y desventajas de cada uno, y los parámetros para reestablecerla. Materiales y Métodos: Se recopiló información científica desde las bases electrónicas Medline/Pubmed, EBSCO y Schoolar Google desde Enero del 2010, hasta Marzo del 2016 tanto en Inglés y Español, utilizando las palabras Dimensión Vertical Oclusal, Altura Facial Inferior y Espacio de Inoclusión Fisiológica, se leyeron los títulos y resúmenes para descartar los artículos no relacionados, eliminando los repetidos. Resultados y Discusión: La relación proporcional entre los segmentos de la cara varían de acuerdo a los estudios, de estos, las mediciones antropométricas presentan el mayor número de discrepancias, y sus resultados no pueden ser aplicados a todos los individuos. Conclusiones: no hay un método único que determine con exactitud la Dimensión Vertical Oclusal, ni evidencia científica que respalde la asociación de Trastornos Témporo Mandibulares con variaciones en la misma, incrementos de 5mm son predecibles y aunque pueden manifestar incomodidades iniciales a los pacientes, son auto limitante y remiten en pocos días.

ABSTRACT Background: The evaluation of the Occlusal Vertical Dimension is an important phase in the diagnosis and treatment planning that determines the aesthetic and functional relationships between the jaws. Objective: To know the methods that help to determine it, the advantages and disadvantages of each one, and the parameters to reestablish it. Materials and Methods: Scientific information was collected from the electronic databases Medline / Pubmed, EBSCO and Schoolar Google from January 2010 to March 2016 in both English and Spanish, using the words Occlusal Vertical Density, Lower Facial Height and Physiological Inoculation Space, Titles and abstracts were read to discard unrelated articles, eliminating repeated ones. Results and Discussion: The proportional relationship between the segments of the face varies according tothe studies; out of these, the anthropometric measurements present the greatest number of discrepancies, and their results can not be applied to all individuals. Conclusions: There is no single method that accurately determines the occlusal vertical dimension, nor scientific evidence supporting the association of temporomandibular disorders with variations in it; increments of 5mm are predictable and although they may cause initial discomforts to patients, they are self-limiting and diminish in a few days.

Determinación del biotipo facial basado en características fenotípicas a través del modelo de ecuaciones estructurales: estuDio sobre tres etnias / Determining facial biotype based upon phenotypic features through structural equation modeling: a study of three ethnic groups

Introducción: el conjunto de características fenotípicas se pueden agrupar y además determinar el peso individual y colectivo que tienen a la hora de definir un biotipo. El modelo de ecuaciones estructurales (MES) se basa en relaciones causales en las que el cambio de una variable se supone que produce un cambio en otras variables. Con este modelo se validaron las relaciones causales a partir de diferentes tipos de variables mediadoras: fuerza de mordida, medidas transversales, arcos dentales, anchura bicigomática y altura morfológica de la cara. Métodos: el estudio incluyó 197 preadolescentes entre 12 y 14 años en condiciones de neutroclusion dental. El 33% mestizos, 35% afrodescendiente y 32% indígenas. El modelo hipotético fue puesto a prueba estadísticamente a través del modelo de ecuaciones estructurales. Resultados: existe un buen ajuste del modelo a los datos puesto que los indicadores de bondad de ajuste como el RMSEA = 0,078, la magnitud del índice RMR = 0,061 y el CIF = 0,988 estuvieron en el umbral esperado. Los parámetros fueron significativos, al nivel del 5%, a excepción del índice facial con la fuerza de mordida. Las cargas factoriales oscilan entre 0,55 y 0,92 y una carga factorial negativa entre el índice facial y las medidas transversales del arco dental (-0,60). Conclusión: el modelo evidencia que la variable latente que más se correlaciona con el biotipo facial es la fuerza de mordida (0,82), seguida de la relación con los arcos dentales (0,73), siendo esta una correlación moderada.

Introduction: the various phenotypic characteristics may be grouped; also, their individual and collective influence may be determined when defining a biotype. Structural equation modeling (SEM) is based on causal relations so that the change in a variable is supposed to produce a change in another variable. This model was used to validate causal relations using different types of mediating variables: masticatory force, transverse measures, dental arches, bizygomatic width, and morphological face height. Methods: this study included 197 preteens between 12 and 14 years of age with dental neutroclusion, distributed like this: 33% mestizos, 35% of African descent, and 32% indigenous. The hypothetical model was statistically tested through structural equation modeling. Results: the model is well fitted to the data since goodness of fit indicators such as RMSEA = 0.078, RMR index magnitude = 0.061, and CIF = 0.988 were within the expected limits. The parameters were significant to a 5%, except for facial index with masticatory force. Factor loads ranged from 0.55 to 0.92 and negative factor loads between the facial index and dental arch transverse measures (–0.60). Conclusion: this model shows that the variable that best correlates with facial biotype is masticatory force (0.82), followed by dental arches relation (0.73), this being a moderate correlation.

Picos de crecimiento facial vertical antes de los 12 años de edad y su relación con el desarrollo puberal en 44 mestizos colombianos sin tratamiento / Vertical facial growth peaks before the age of 12 and their relation with pubertal development in 44 untreated Colombian mestizos

Introducción: la mayoría de las investigaciones del crecimiento facial se enfocan hacia la documentación y predicción del crecimiento puberal opacando la descripción del crecimiento antes de los 12 años de edad. Aunque hay varias investigaciones en poblaciones caucásicas que han reportado los picos tempranos de crecimiento, ninguna lo ha ubicado y dimensionado con relación al pico puberal. En mestizos latinoamericanos no hay estudios reportados en la literatura. Métodos: desde 1992 el Grupo de Investigación de Labio y Paladar Hendido, Fisiología Oral y Crecimiento Craneofacial, CES-LPH, está haciendo un estudio longitudinal del crecimiento facial en 44 mestizos colombianos sin tratamiento con una muestra de 373 radiografías cefálicas laterales obtenidas durante 18 años de seguimiento. Resultados: de las 28 niñas de la muestra, 21 (75%) presentaron incrementos bienal mayores de 5 mm en la altura facial anterior (AFA) antes de los 12 años. En la altura facial posterior (AFP) hubo 9 (32%) niñas con incrementos bienales mayores a 5 mm antes de los 9 años. En 7 (43%) niños se presentaron incrementos bienales mayores a 5 mm en AFA antes de los 12 años y para la AFP hubo 9 (56%) niños con el mismo comportamiento antes de los 12 años. Para 5 de las niñas y 3 de los niños (18%), este fue el mayor pico de crecimiento en todo el seguimiento de la muestra desde los 6 hasta los 19 años, hallazgo no reportado anteriormente en la literatura. Conclusiones: los picos tempranos de crecimiento vertical (AFA y AFP) en niños menores de 9 años pueden explicar el éxito de las terapias tempranas de ortopedia funcional de los maxilares.

Introduction: most studies on facial growth focus on documenting and predicting pubertal growth, underestimating the description of growth before the age of 12. Although several studies on Caucasian populations have analyzed early growth peaks, none of the publications has related them with the pubertal peaks. Furthermore, no studies on Latin American mestizos are reported in the literature. Methods: since 1992, the Cleft Lip and Palate, Oral Physiology and Craniofacial Growth Research Group (CES-LPH for its Spanish initials) has been conducting a longitudinal study on facial growth in 44 untreated Colombian mestizos with a sample of 373 cephalic lateral radiographs obtained during a period of 18 years. Results: 21 of the 28 girls in the sample (75%) present major biennial increments of 5 mm in anterior face height (AFH) before age 12. In terms of posterior face height (PFH), there were 9 girls (32%) with biennial increases greater than 5 mm before 9 years old. 7 children (43%) presented biennial increases greater than 5 mm in AFH before the age of 12, and concerning PFH there were 9 children (56%) with the same behavior before the age of 12. For 5 girls and 3 boys (18%), this was the greatest growth peak throughout the follow-up period of a sample since the age of 6 until 19 years—a finding not previously reported in the literature—. Conclusions: early vertical growth peaks (AFH and PFH) in children younger than 9 years may explain the success of early functional jaw orthopedic therapies.

Avaliação da proporção facial vertical: relação entre as alturas tegumentar e esquelética / Evaluation of facial proportions in the vertical plane to investigate the relationship between skeletal and soft tissue dimensions

OBJETIVO: determinar a relação entre as alturas faciais obtidas na avaliação do tegumento e do esqueleto subjacente, na análise da proporção facial vertical, na região anterior. MÉTODOS: foram utilizadas 24 radiografias cefalométricas de perfil e 48 fotografias da face, sendo 24 de perfil e 24 frontais, pertencentes a 24 indivíduos brasileiros, 7 do sexo masculino e 17 do feminino, na faixa etária de 19 a 38 anos. Foram realizados traçados cefalométricos e, sobre esses, obtidas medidas lineares, segundo as análises preconizadas por Schudy, Wylie e Johnson e Thompson e Brodie. Sobre as fotografias faciais, foram demarcados os pontos glabela, subnasal e mento, o que permitiu a medição das distâncias lineares entre os mesmos. Os dados obtidos foram, então, tratados estatisticamente. RESULTADOS E CONCLUSÕES: encontrou-se correlação positiva entre as avaliações do tegumento e do esqueleto subjacente, com base nas análises de Schudy (r=0,619, p<0,001), Wylie e Johnson (r=0,595, p<0,002) e Thompson e Brodie (r=0,630, p<0,001), embora, individualmente, algumas discordâncias tenham sido identificadas, devido à variabilidade em espessura nos tecidos moles.

OBJECTIVE: To determine the relationship between facial heights by evaluating the soft tissues and underlying skeleton and by analyzing vertical facial proportions in the anterior region. METHODS: The study used 24 lateral cephalometric x-rays and 48 photographs of the face, 24 in profile view and 24 in front view, belonging to 24 Brazilian individuals, 7 men and 17 women whose ages ranged from 19 to 38 years. Cephalometric tracings were performed and linear measurements obtained according to the analyses suggested by Schudy, Wylie & Johnson, and Thompson & Brodie. The anatomical landmarks glabella, subnasal and menton were identified on the photographs, which allowed the measurement of linear distances between these points. The data were then statistically analyzed. RESULTS AND CONCLUSIONS: A positive correlation was found between evaluations of the soft tissues and underlying skeleton based on the analyses advanced by Schudy (r=0.619, p<0.001), Wylie & Johnson (r=0.595, p<0.002) and Thompson & Brodie (r=0.630, p<0.001), although, individually, some discrepancies were identified due to variability in soft tissue thickness.

Características craneofaciales en pacientes con desgaste dentario severo / Craniofacial characteristics in patients with severe toothwear

Introducción: con la finalidad de contrastar la hipótesis nula “no existen diferencias significativas en lascaracterísticas arquitecturales y estructurales craneofaciales entre individuos con y sin desgaste dentario” se realizó un estudio analítico, no experimental de casos y controles en pacientes que consultaron por tratamiento prostodóncico u ortodóncico. Métodos: la muestra quedó conformada por 26 pacientes con desgate dentario severo (estudio) y 52 pacientes sin desgaste dentario (control).El grupo control se obtuvo por pareamiento según sexo, rango de edad y ángulo de la base de cráneo. Todos ellos poseían estabilidad oclusal y no presentaban tratamiento ortodóncico previo, procedimientos quirúrgicos maxilofaciales ni patologías de crecimiento y desarrollo. Se utilizó un cefalograma específicamente diseñado que incluyó los parámetros arquitecturales y estructurales delanálisis de Delaire. Para el análisis de los datos fueron utilizados el t Test y el Chi cuadrado dependiendo de la naturaleza de los datos. Resultados: diferencias significativas fueron encontradas particularmente a nivel del hueso basal maxilar y mandibular y en la posición del plano oclusal real respecto al plano oclusal teórico. Conclusiones: se concluyó que en pacientes con desgaste dentario severo, se produce una modificación del hueso basal y mandibular por remodelación del proceso dentoalveolar que resulta en una rotación craneal del plano oclusal. Se observa aparente estabilidad de la altura facial y del ángulo mandibular a pesar del cambio obvio de la posición del plano oclusal.

Introduction: in order to test the null hypothesis “there are no significant differences in the craniofacial architectural and structural characteristics among individuals with and without severe tooth wear”, a non experimental analytic case controlstudy was carried out with patients who consulted for prosthodontic or orthodontic treatment. Methods: 78 patients between 22 and 55 years of age participated. The experimental group consisted of 26 patients between 29 and 55 years of age (9 women and17 men). The control group consisted of 52 patients between 22 and 50 years of age (18 women and 34 men) matched by gender —age range and posterior cranium base angle. All of them had occlusal stability, without previous orthodontic treatment, surgeryor growth and development alterations. The measuring instrument was a specifically designed cephalogram which included the architectural and structural parameters from Delaire’s Analysis, combined with some extra radiographic points defined by the authors for this particular study. The parameters under investigation were different cranial structural relationships includingocclusal plane position. Statistical analysis using t-test, Chi square test and Pearson’s correlation test were carried out depending of the nature of the data. Results: significant differences were particularly found on maxillary and mandibular basal bone and on the position of the actual occlusal plane with respect to the theoretical plane. Conclusions: it was concluded that in patients with severe tooth wear, a modification of the maxillary and mandibular basal bone could have taken place with remodelling of the dental alveolar process resulting in a cranial rotation of the occlusal plane. An apparent stability of the facial height and the mandibular angle was observed in spite of the obvious change in the position of the occlusal plane.

Análise correlativa entre medidas esqueléticas verticais em indivíduos com oclusão excelente e má oclusão / Correlative analysis between vertical measurements in individuals with excellent occlusion and malocclusion

INTRODUÇÃO: avaliar as proporções verticais faciais é um dos parâmetros mais importantes a ser utilizado pelo ortodontista no planejamento da terapia apropriada. Porém, não é raro que, quando se avaliam medidas isoladamente, tenha-se uma idéia errônea do que a face do paciente apresenta em termos de padrão vertical. OBJETIVOS: o presente trabalho realizou diferentes correlações entre a ângulo do plano mandibular (GoGn-SN), o índice de altura facial (IAF) e a sobremordida, avaliando a resposta dessas correlações quanto ao padrão citado na literatura, além de identificar possíveis fatores que, eventualmente, levassem essas medidas a um comportamento fora desse padrão. METODOLOGIA: o estudo foi realizado em radiografias cefalométricas de perfil entre dois grupos de indivíduos brasileiros - um portador de oclusão excelente e outro de má oclusão - atendidos no Curso de Especialização em Ortodontia e Ortopedia Facial da Faculdade de Odontologia da Universidade Federal da Bahia. RESULTADOS: as medidas esqueléticas GoGn-SN e IAF apresentaram forte correlação entre si. A sobremordida, entretanto, não apresentou correlação com essas medidas no grupo com oclusão excelente e demonstrou fraca correlação naquele com má oclusão. Uma correlação coerente com o padrão citado na literatura foi encontrada em 35 por cento e 31 por cento dos indivíduos dos grupos com oclusão excelente e má oclusão, respectivamente. Os indivíduos restantes apresentaram variações na altura dentoalveolar dos incisivos, compensando as displasias verticais. No grupo com oclusão excelente, esse fator se somou às compensações na região de molares. CONCLUSÕES: os resultados encontrados indicam que a maior parte dos grupos apresentou um comportamento diferente do padrão citado na literatura, quando as três medidas foram correlacionadas simultaneamente.

INTRODUCTION: The evaluation of facial vertical proportions is one of the most important features considered by the orthodontist when choosing the appropriate therapy. Meanwhile, when vertical measurements are analyzed separately, one could have an unreliable idea of what the patient's face presents considering vertical development. AIM: The purpose of this research was to perform a correlative analysis between the vertical cephalometric measurements: mandibular plane angle (GoGn-SN), facial height index (FHI) and overbite; to evaluate if the simultaneous correlation of these measurements is in agreement with the results cited in the literature; and to identify the possible factors which could, eventually, lead to different results from those expected. METHODS: This study was performed through cephalometric x-rays obtained from randomly chosen individuals with excellent occlusion and malocclusion, selected from the Orthodontics Program of the Federal University of Bahia. RESULTS: The skeletal measurements GoGn-SN and FHI showed strong correlation. The overbite level did not showed correlation with these measurements in the excellent occlusion group, and showed weak correlation in the malocclusion group. Only 35 percent of the individuals with excellent occlusion showed an expected correlation between the three measurements, while this percentage was of 31 percent in the malocclusion group. The remaining individuals showed variations in the incisor dentoalveolar heights as a major factor in compensating the vertical dysplasia, and in the excellent occlusion group it was also found compensations in the molars area. CONCLUSIONS: The results indicates that the most part of the groups presented a correlation between the three vertical measurements different from the pattern related in the literature.

Estudio estadístico de la altura facial inferior y su correcta clasificación. (1a. parte) / Statistical study of the lower facial height and correct classification (Part. 1)

Es fundamental a la hora de establecer un diagnostico, contar con las herramientas adecuadas y a su vez utilizar estas en forma eficiente. Es conocido que la cuantificación objetiva que nos dan en las medidas cefalométricas nos acercan a establecer patrones y biotipos, pero lejos de ser esta la única vara con la que debemos medir nuestros pacientes es común obtener resultados que se contradicen con una detallada observación clínica del mismo

It is essential when establishing a diagnosis, having the right tools and in turn use these efficiently. It is known that the objective quantification that give us the cephalometric measurements bring us to establish patterns and biotypes, but far from the only yardstick by which we measure our patients is common to get results that conflict with a detailed clinical observation of it