Anatomical variations and morphometric study of pterion in a Thai population associated with clinical implications / Variaciones anatómicas y estudio morfométrico del pterion en una población tailandesa asociada con implicaciones clínicas

SUMMARY: The objective of this study was to consider the type of variation and to estimate the landmarks for localizing the pterion. One hundred twenty Thai dry skulls were selected randomly from the Forensic Osteology Research Center, Faculty of Medicine, Chiang Mai University. The distances of the parameters were measured via Vernier caliper. The sphenoparietal type is the most dominant in the Thai population with 88.75 %. In the male, the distance of the midglabella to the pterion was 9.94?0.64 mm The distance of the frontozygomatic suture to the pterion was 35.41?4.38 mm The distance of the zygomatic arch to the pterion was 39.39?4.69 mm and the distance of the mastoid process tip to the pterion was 86.88?4.44 mm In the female, the distance of the midglabella to the pterion was 9.27?0.63 mm The distance of the frontozygomatic suture to the pterion was 33.08?4.12 mm The distance of the zygomatic arch to the pterion was 33.08?4.12 mm and the distance of the mastoid process tip to the pterion was 83.62?5.16 mm. The pterion approach is the most popular method for neurosurgical procedures, and it provides anatomical variations in the pattern. The sphenoparietal type of pterion is the most common form and the stellate type of pterion is the least common form in Thai skulls. Sex influences the location of the pterion. These findings will be of importance to predict the pterion type in Thai skull and estimate the localization of pterion by using a bony landmark. Knowledge of the precise location of the pterion is an important landmark in the neurosurgical approach.

RESUMEN: El objetivo de este estudio fue considerar el tipo de variación del pterion y estimar los puntos de referencia para localizarlo. Se seleccionaron al azar 120 cráneos secos de individuos tailandeses del Centro de Investigación de Osteología Forense de la Facultad de Medicina de la Universidad de Chiang Mai. Las distancias de los parámetros se midieron mediante un caliper Vernier. El tipo esfenoparietal es el más dominante en la población tailandesa con 88,75 %. En el hombre, la distancia de la glabella al pterion fue de 9,94 ? 0,64 mm. La distancia de la sutura frontocigomática fue de 35,41 ? 4,38 mm La distancia del arco cigomático fue de 39,39 ? 4,69 mm y la distancia del ápice del proceso mastoideo al pterion fue de 86,88 ? 4,44 mm. En la mujer, la distancia de la glabella al pterion fue de 9,27 ? 0,63 mm. La distancia de la sutura frontocigomática al pterion fue de 33,08 ? 4,12 mm. La distancia del arco cigomático al pterion fue de 33,08 ? 4,12 mm y la distancia del ápice proceso mastoideo al pterion fue de 83,62 ? 5,16 mm. El abordaje del pterion es el método más utilizado para procedimientos neuroquirúrgicos y proporciona variaciones anatómicas en el patrón. El tipo esfenoparietal del pterion es la forma más común y el tipo estrellado del pterion es la forma menos común en los cráneos tailandeses. El sexo influye en la ubicación del pterion. Estos hallazgos serán importantes para predecir el tipo de pterion del cráneo en tailandeses y a la vez estimar su localización mediante el uso de un punto de referencia óseo. El conocimiento de la ubicación precisa del pterion es un hito impor- tante en el abordaje neuroquirúrgico.

Morphology of the pterion in Serbian population / Morfología del pterion en población serbia

The pterion is a topographic point on the lateral aspect of the skull where frontal, sphenoid, parietal and temporal bones form the H or K shaped suture. This is an important surgical point for the lesions in anterior and middle cranial fossa. This study was performed on 50 dry skulls from Serbian adult individuals from Department of Anatomy, Faculty of Medicine in Novi Sad. The type of the pterion on both sides of each skull was determined and they are calcified in four types (sphenoparietal, frontotemporal, stellate and epipteric). The distance between the center of the pterion and defined anthropological landmarks were measured using the ImageJ software. Sphenoparietal type is predominant with 86 % in right side and 88 % in left side. In male skulls, the distance from the right pterion to the frontozygomatic suture is 39.89±3.85 mm and 39.67±4.61 mm from the left pterion to the frontozygomatic suture. In female skulls the distance is 37.38±6.38 mm on the right and 35.94±6.46 mm on the left. The shape and the localization of the pterion are important because it is an anatomical landmark and should be used in neurosurgery, traumatology and ophthalmology.

El pterion es un punto topográfico en la cara lateral del cráneo donde los huesos frontales, esfenoides, parietales y temporales forman la sutura en forma de H o K. Este es un punto quirúrgico importante para las lesiones en la fosa craneal anterior y media. Este estudio se realizó en 50 cráneos secos de adultos serbios del Departamento de Anatomía de la Facultad de Medicina de Novi Sad. Se determinó el tipo de pterión en ambos lados de cada cráneo y se calcifican en cuatro tipos (esfenoparietal, frontotemporal, estrellado y epipterico). La distancia entre el centro del pterion y los puntos de referencia antropológicos definidos se midió utilizando el software ImageJ. El tipo esfenoparietal es predominante con 86 % en el lado derecho y 88 % en el lado izquierdo. En los cráneos masculinos, la distancia desde el pterion derecho hasta la sutura frontocigomática es 39,89 ± 3,85 mm y 39,67 ± 4,61 mm desde el pterion izquierdo hasta la sutura frontocigomática. En los cráneos femeninos, la distancia es 37,38 ± 6,38 mm a la derecha y 35,94 ± 6,46 mm a la izquierda. La forma y la localización del pterion son importantes debido a que es un indicador anatómico y debe usarse en neurocirugía, traumatología y oftalmología.

Correlation analysis of infraorbital foramen with related anatomical structures / Análisis de correlación del foramen infraorbitario con estructuras anatómicas relacionadas

The anatomical localization of foramen infraorbitale (FOI) and its relationship with ambient structures are of great importance for clinicians and surgeons. This study was performed on seventy five skulls, and the distance between FOI to important anatomical formations, angular position of the zygomatic bone and the relationship between these parameters were investigated on both sides. The distance of FOI to margo infraorbitalis (MI), apertura piriformis (AP) and spina nasalis anterior (SNA), upper face height (UH) and upper face width (UW) were measured. Zygomatic bone triangle angles (SA, PA, IA) and porion-nasion-spina nasalis anterior angle (PNS) were measured from lateral view of the skull. While there was no significant difference between right and left measurement except for PA (p=0.03), the distance from FOI to MI is showed a very high degree positive correlation between the right and left sides, the distance from the FOI to AP was weak correlated only right side.

La localización anatómica del foramen infraorbitario (FIO) y su relación con las estructuras adyacentes son de gran importancia para los médicos y cirujanos. Este estudio se realizó en setenta y cinco cráneos, y se investigó la distancia entre FIO a formaciones anatómicas importantes, la posición angular del hueso cigomático y la relación entre estos parámetros en ambos lados. Se midió la distancia de FIO al margen infraorbitario (MI), apertura piriforme (AP) y espina nasal anterior (ENA), altura superior de la cara (AC) y ancho superior de la cara (AC). Los ángulos del triángulo óseo cigomático y el ángulo anterior porion-nasion-epina nasal se midieron desde la vista lateral del cráneo. Si bien no hubo una diferencia significativa entre la medición derecha e izquierda, a excepción AP (p = 0,03), la distancia de FIP a MI mostró una correlación positiva de alto grado entre los lados derecho e izquierdo, la distancia de FIO a AP fue débil correlacionado solo en el lado derecho.

Los tipos craneométricos caninos aparecen bien expresados a nivel de conformación del arco cigomático / Craneometric canine types are well expressed at the level of the zygomatic arch conformation

Dentro del espectro de conformación del cráneo, se reconocen generalmente tres amplias categorías que se corresponden con el concepto de biotipo cefálico, determinado por el Índice Cefálico. El Estos tres biotipos cefálicos son: el braquiocefálico, mesaticefálico y dolicocefálico, pero están basados en medidas lineales. A fin de revisar esta clasificación en base a su geometría, se estudiaron 53 cráneos de perros adultos, correspondientes a los tres grupos craneométricos descritos: 16 braquicéfalos, 20 mesaticéfalos y 17 dolicocéfalos. Para ello se obtuvieron fotografías en el plano ventral, en las que posteriormente se ubicaron 17 hitos anatómicos que se analizaron mediante técnicas de morfometría geométrica. De estos hitos, 5 correspondían a la zona neurocraneal y el resto al esplacnocráneo. Los tres grupos craneométricos mostraron diferencias estadísticamente significativas entre ellos tanto por el tamaño como por la forma. Las variables que contribuyeron más a explicar la diferenciación fueron las ubicadas en el margen más lateral de los arcos cigomáticos y en la base de este mismo arco. Las variables esplacnocraneales presentaban una alometría mucho más marcada que las neurocráneos. Puesto que el arco cigomático debe ser considerado como parte del esplacnocráneo, sugerimos que es tan importante el índice cefálico (que tiene en cuenta la máxima anchura de la cabeza) como el facial (que tiene en cuenta la máxima anchura de la cara). La conformación neurocraneal sería mucho más conservativa y por ende el índice craneal, de mucho menor poder discriminatorio entre grupos. El cambio entre tipos se debería a los músculos masetero y temporal, que tienen su inserción en el arco.

Within the wide conformation of skull spectrum, there are generally three recognized broad categories that correspond to the concept of cephalic biotype, determined by the cephalic index. The three cephalic biotypes are: brachiocephalic, mesaticephalic and dolichocephalic, which are based on linear measures. In order to revise this classification based on its geometry, we studied 53 skulls of adult dogs, corresponding to the three craneometric groups previously described: 16 brachycephalic, 20 mesaticephalic and 17 dolichocephalic. Images on ventral plane were obtained and 17 anatomical landmarks were subsequently located and analyzed by means of geometric morphometric techniques. Five of those landmarks corresponded to the neurocraneal area and the rest of the splanchnocranium. The three craneometric groups showed statistically significant differences between them for both size and shape. The variables that contributed to the differentiation between them were located along the edge of the zygomatic arches and on the basis of this arch. Splanchnocranial variables also presented a much more marked allometry than the neurocraneal variables. Since the zygomatic arch should be considered as part of the splanchnocranium, we suggest that the cephalic index (which takes into account the maximum width of the head) is as important as the facial index (which takes into account the maximum width of the face). The neurocraneal index would be much more conservative, and therefore less discriminatory between the groups.

Tubérculo marginal del hueso cigomático / Marginal tubercle of zygomatic bone

El hueso cigomático, ubicado en la parte superior y lateral de la cara, es un hueso par e irregular con forma cuadrilátera o romboidal. Se describen 2 caras, 4 aristas y 4 ángulos, forma cavidades, permite la inserción muscular y aponeurótica, es parte de la arquitectura facial, distribuye las fuerzas masticatorias y permite el paso del nervio cigomático. Su margen postero-superior presenta una prominencia ósea conocida como tubérculo marginal, en el que se observa la inserción de la fascia temporal. El objetivo de este trabajo fue describir las características particulares de esta prominencia. La muestra correspondió a 30 cráneos de adultos chilenos de ambos sexos. A través de una serie de puntos óseos, se describió la presencia, ubicación, tamaño, forma, cortical y trabeculado del tejido óseo del tubérculo marginal. Para realizar las mediciones se utilizaron cámara digital, compas de precisión y cáliper digital. El análisis radiográfico requirió tomografía computarizada de alta resolución. Los resultados mostraron que el tubérculo marginal del hueso cigomático es una prominencia constante, ubicada en el tercio medio del proceso frontal del hueso y que la mayoría de los individuos mostraron una forma semilunar. Su altura fluctúa entre 3 y 4 mm, siendo más pronunciada en hombres que en mujeres. El grosor de la corteza ósea es directamente proporcional a la prominencia del tubérculo, mientras que el trabeculado esponjoso está inversamente relacionado con este último. El análisis de estos resultados parece indicar que las fuerzas biomecánicas ejercidas por la musculatura masticatoria y transmitidas por la fascia temporal, determinan la morfología externa e interna de esta prominencia y del propio hueso cigomático. Concluimos, declarando la necesidad de revisar el conocimiento anatómico a la luz de las nuevas técnicas de imagen e integración disciplinar.

The zygomatic bone, located in the upper and lateral area of the face, is an even and irregular quadrilateral or rhomboid shaped bone. It presents 2 faces, 4 margins and 4 angles. It forms cavities, allows muscular and aponeurotic insertion, is part of the facial architecture, distributes masticatory forces and allows the passage of the zygomatic nerve. Its postero-superior margin presents a bony prominence known as a marginal tubercle, in which the insertion of the temporal fascia is observed. The objective of this work was to describe the particular characteristics of this prominence. The sample corresponded to 30 skulls of Chilean adults of both sexes. Through a series of bone points, the presence, location, size, shape, cortical and trabeculate of the bone tissue of the marginal tubercle was described. A digital camera, precision compass and digital caliper were used to perform the measurements. The radiographic analysis required high-resolution computed tomography. The results showed that the marginal tubercle of the zygomatic bone is a constant prominence, located in the middle third of the frontal process of the bone and that most individuals showed a semilunar shape. Its height fluctuated between 3 and 4 mm, being more pronounced in men than in women. The thickness of the bone cortex was directly proportional to the prominence of the tuber, while the spongy trabeculate was inversely related to the latter. The analysis of these results seems to indicate that the biomechanical forces exerted by the masticatory musculature and transmitted by the temporal fascia, determine the external and internal morphology of this prominence, and of the zygomatic bone itself. In conclusion, it is recommended to review anatomical knowledge in the light of new imaging techniques and disciplinary integration.

Bizygomatic width and personality traits of the relational field / Ancho bizigomático y rasgos de personalidad del campo relacional

SUMMARY: The bizygomatic width when compared to the bigonial width (WD) has been proposed as a craniofacial marker of some social and personality traits, such us self-reliance or the ability to express emotions. However, no studies have examined the association between WD and psychopathic traits, as happens with other craniofacial variables such us the facial width-to-height ratio (fWHR). In a sample of 70 adults (male and female) we took measures of the bizygomatic and the bigonial arches. Subjects performed self-assessment tests to evaluate their self-reliance, their alexithymia and emotional expressiveness and their coldheartedness or callousunemotional. Results showed a significant relationship between WD and self-reliance, emotional expression and alexithymia, and a tendency towards significance with general psychopathic scores. Additionally, we found a modificatory effect of the variables sex and age when analyzing the influence of the WD on the Factor 3 - "Coldheartedness" of the Psychopathic Personality Inventory-Revised (PPI-R), where this effect diminished depending on the subject's sex and age. Results suggested that the WD seem to be a good marker to be taken into consideration in further research that examines craniofacial traits and personality traits of the socio-emotional field.

RESUMEN: La anchura bicigomática en comparación con la anchura bigonial (WD) se ha propuesto como marcador craneofacial de algunos rasgos sociales y de personalidad, como la independencia/gregarismo o la capacidad de expresión emocional. Sin embargo, ningún estudio ha examinado la asociación entre la WD y los rasgos psicopáticos, como ocurre con otras variables craneofaciales, como la ratio anchura / altura facial (fWHR). En una muestra de 70 adultos (hombres y mujeres) tomamos medidas de los arcos bizigomático y bigonial. Los sujetos realizaron pruebas de autoevaluación para evaluar la capacidad de incorporarse al grupo, la alexitimia y la expresividad emocional, y la frialdad o la insensibilidad emocional. Los resultados mostraron una relación significativa entre WD con independencia/gregarismo, expresión emocional y alexitimia, así como una tendencia hacia la significación con la psicopatía en general. Adicionalmente, encontramos un efecto modificador de las variables sexo y edad al analizar la influencia de la WD en el Factor 3 - "Coldheartness" del Inventario de Personalidad Psicopática-Revisado (PPI-R), donde este efecto disminuye según sexo y edad. Los resultados sugieren que el WD parece ser un buen marcador para tener en cuenta en futuras investigaciones que examinen los rasgos craneofaciales y los rasgos de personalidad del campo socioemocional.

Bizygomatic width and its association with social and personality traits in males / Distancia bicigomática y su asociación con habilidades sociales y rasgos de personalidad en hombres

This study will examine how differences in measurements between bizygomatic and bigonial arches of the human face can provide relevant information regarding personality and abilities of the subject. Sample: 82 males. Group A: 55 subjects with the bizygomatic arch in contraction. Group B: 27 subjects without the bizygomatic arch in contraction. Subjects performed self-assessment tests in the following areas: ability incorporating themselves into the group, alexithymia and emotional expressiveness. Group A showed greater self-sufficiency and independence than group B, greater difficulty in describing and verbally expressing their emotions, less ability to express themselves emotionally through other forms of communication and reduced willingness to cooperate philanthropically. Results suggest a strong relationship between morphological structure of the bizygomatic arch and certain psychological characteristics.

Este estudio examina cómo la diferencia entre las anchuras del arco bicigomático y bigonial en la cara humana, proporcionan información relevante sobre la personalidad y las habilidades de un sujeto. Muestra: 82 hombres. Grupo A: 55 sujetos con el arco bicigomático en contracción. Grupo B: 27 sujetos con el arco bicigomático sin retracción. Los sujetos realizaron pruebas de autoevaluación en las siguientes áreas: adhesión/independencia al grupo, alexitimia y expresividad emocional. El grupo A mostró respecto al grupo B una mayor autosuficiencia e independencia, mayor dificultad para describir y expresar verbalmente sus emociones, menor capacidad para expresarse emocionalmente a través de diferentes formas de comunicación y reducción de la voluntad de cooperar filantrópicamente. Los resultados sugieren una fuerte relación entre la estructura morfológica del arco bicigomático y ciertas características psicológicas.

Assessing bone thickness in the infrazygomatic crest area aiming the orthodontic miniplates positioning: a tomographic study

ABSTRACT Introduction: Due to the increasing use of miniplates for anchorage purposes in orthodontics, it is very important to know more about infrazigomatic crest anatomy (thickness), in adult patients. Objectives: Evaluate the infrazygomatic crest region thickness, in adult (male and female) patients. Methods: Cone-beam computerized tomography (CBCT) images from 40 patients were used to assess cross-sectional measurements of the infrazygomatic crest region. Measurement 1 considered thickness 2 mm above the distobuccal root of the permanent maxillary first molar, while measurement 2 was taken 2 mm above the first measurement. Results: The mean thickness of the infrazygomatic crest in males was 3.55 mm for measurement 1 and 2.84 mm for measurement 2, while in females these were 2.37 mm and 2.24 mm, respectively. Conclusion: The authors concluded that the overall mean thickness of the infrazygomatic crest was 2.49 mm with respect to measurement 1, and 2.29 mm for measurement 2, with no statistically significant differences between gender.

RESUMO Introdução: devido ao aumento do uso de miniplacas para ancoragem em Ortodontia, torna-se de fundamental importância compreender melhor a anatomia da crista infrazigomática (espessura) em pacientes adultos. Objetivos: avaliar a espessura da crista infrazigomática em pacientes adultos (sexos feminino e masculino). Métodos: foram utilizadas tomografias computadorizadas de feixe cônico (TCFC) de 40 pacientes, para avaliar medidas da região da crista infrazigomática, no sentido transversal. A Medida 1 verificou a espessura mm acima da raiz distovestibular do primeiro molar permanente superior, enquanto a Medida 2 foi realizada 2 mm acima da primeira medida. Resultados: a espessura média da crista infrazigomática encontrada no sexo masculino foi de 3,55 mm para a Medida 1 e de 2,84 mm para a Medida 2, e no sexo feminino foi de 2,37 mm e de 2,24 mm, respectivamente. Conclusão: os autores puderam constatar que a espessura média da crista infrazigomática foi de 2,49 mm para a Medida 1, e de 2,29 mm para a Medida 2, sem diferença estatisticamente significativa entre os sexos.

Anatomical and radiographic study of the white-eared opossum (Didelphis albiventris) skull / Estudo anatômico e radiográfico do crânio no gambá-de-orelha-branca (Didelphis albiventris)

This study was made to investigate the anatomical features of the white-eared opossum skull, by osteology and radiographic anatomy. For this, five animals were used without sexual distinction. The skull was examined by radiographic and macroscopic characteristics. The skulls were then subjected to maceration. The skull was described macroscopically according to standard views, i.e. dorsal and caudal, lateral, ventral, and midsagittal. The skull can be divided into facial (viscerocranium) and cranial (neurocranium) regions. The facial region was elongated and more developed than neurocranium. The supraorbital foramen was absent. The tympanic bulla is not well developed. The zygomatic arch was formed by zygomatic process of the temporal bone, zygomatic process of the maxilla, and temporal process of the zygomatic bone. There was no significant difference between bones found in this study when compared with those described for others mammals. These findings may contribute to the better understanding of the anatomy and biology of the white-eared opossum.(AU)

Este estudo objetivou investigar as características anatômicas do crânio do gambá-de-orelha-branca, através da anatomia óssea e radiográfica. Para tanto, cinco animais foram usados sem distinção sexual. O crânio foi estudado através de análises radiográficas e macroscópicas. Para esta última, os crânios foram macerados. O crânio foi descrito macroscopicamente de acordo com as vistas ou normas rotineiras, isto é, dorsal e caudal, lateral, ventral e sagital. O crânio pode ser dividido em regiões facial (viscerocrânio) e cranial (neurocrânio). A região facial se mostrou alongada e mais desenvolvida que o neurocrânio. O forame supraorbital estava ausente. A bula timpânica não era bem desenvolvida. O arco zigomático era formado pelo processo zigomático do osso temporal, processo zigomático da maxila, e pelo processo temporal do osso zigomático. Não houve diferenças significativas entre os ossos estudados quando comparados com os já descritos para outros mamíferos. Estes resultados podem contribuir com um melhor entendimento da anatomia e biologia deste animal.(AU)

Photoelastic Analysis of Two Maxillary Protocols Using Zygomatic Implants / Análisis Fotoelástico de Dos Protocolos Maxilares con Uso de Implantes Cigomáticos

The aim of this study was to analyse the in vitro the stress distribution in craniofacial structures around zygomatic implants. Synthetic polyurethane skulls replicas were used as templates for installation of standard and zygomatic implants performing two techniques using rehabilitation with using one zygomatic implant in the right and left side in combination with 2 and 4 standard implants in the anterior maxilla (group 1 and group 2). The skull replicas of photoelastic resin were subjected to photoelastic analysis after linear loading using an Instron 4411 servohydraulic mechanical testing, with a 2 mm displacement. The stress distribution showed the fringes with concentration in the body and the frontal process of zygomatic bone. In the case of model 1, higher concentrations of stress were found around the standard and zygomatic implants and surrounding bone. Under this condition, the rehabilitation with 2 zygomatics implants and 4 standard implants (group 2) provided the most favorable behavior.

El objetivo de este estudio fue analizar el estrés in vitro y la distribución de tensiones en la estructura craneofacial a partir de los implantes cigomaticos. Réplicas de cráneo de poliuretano fueron usados como modelos para la instalación de implantes cigomáticos estándar utilizando dos modelos de distribución de implantes. Estos modelos fueron usados como modelos utilizando 1 implante en cada lado con dos o cuatro implantes convencionales en la región anterior maxilar (grupo 1 y grupo 2); posteriormente, se realizó una carga compresiva unilateral en la máquina Instrom 4411 utilizando 2 mm de desplazamiento máximo. La distribución de estrés se concentró principalmente en la región de cuerpo de hueso cigomático y en la región frontal del proceso cigomático; el modelo 1, con dos implantes convencionales, mostró mayor distribución de estrés en la región cigomática al comparase con el grupo 2; bajo estas condiciones, se concluye que la distribución con cuatro implantes convencionales entrega mejores condiciones de distribución de tensiones.

Analysis of Age-Related Changes in Asian Facial Skeletons Using 3D Vector Mathematics on Picture Archiving and Communication System Computed Tomography

PURPOSE: There are marked differences in facial skeletal characteristics between Asian and Caucasian. However, ethnic differences in age-related facial skeletal changes have not yet been fully established. The aims of this study were to evaluate age-related changes in Asian midfacial skeletons and to explore ethnic differences in facial skeletal structures with aging between Caucasian and Asian. MATERIALS AND METHODS: The study included 108 men (aged 20-79 years) and 115 women (aged 20-81 years). Axial CT images with a gantry tilt angle of 0 were analyzed. We measured three-dimensional (3D) coordinates at each point with a pixel lens cursor in a picture archiving and communication system (PACS), and angles and widths between the points were calculated using 3D vector mathematics. We analyzed angular changes in 4 bony regions, including the glabellar, orbital, maxillary, and pyriform aperture regions, and changes in the orbital aperture width (distance from the posterior lacrimal crest to the frontozygomatic suture) and the pyriform width (between both upper margins of the pyriform aperture). RESULTS: All 4 midfacial angles in females and glabellar and maxillary angles in males showed statistically significant decreases with aging. On the other hand, the orbital and pyriform widths did not show statistically significant changes with aging. CONCLUSION: The results of this study suggest that Asian midfacial skeletons may change continuously throughout life, and that there may be significant differences in the midfacial skeleton between both sexes and between ethnic groups.

Relationship between facial morphology, anterior open bite and non-nutritive sucking habits during the primary dentition stage

INTRODUCTION: Non-nutritive sucking habits (NNSHs) can cause occlusal alterations, including anterior open bite (AOB). However, not all patients develop this malocclusion. Therefore, the emergence of AOB does not depend on deleterious habits, only. OBJECTIVE: Investigate a potential association between non-nutritive sucking habits (NNSHs), anterior open bite (AOB) and facial morphology (FM). METHODS: 176 children in the primary dentition stage were selected. Intra and extraoral clinical examinations were performed and the children's legal guardians were asked to respond to a questionnaire comprising issues related to non-nutritive sucking habits (NNSHs). RESULTS: A statistically significant relationship was found between non-nutritive sucking habits (NNSHs) and anterior open bite (AOB). However, no association was found between these factors and children's facial morphology (FM). CONCLUSIONS: Non-nutritive sucking habits (NNSHs) during the primary dentition stage play a key role in determining anterior open bite (AOB) malocclusion regardless of patient's morphological facial pattern (FM). .

INTRODUÇÃO: os hábitos de sucção não nutritiva podem causar alterações oclusais, como, por exemplo, a mordida aberta anterior (MAA). No entanto, nem todos os pacientes desenvolvem essa má oclusão. Sendo assim, a instalação da MAA não depende apenas da ocorrência do hábito. OBJETIVO: avaliar a possível associação entre hábito de sucção não nutritiva, mordida aberta anterior e morfologia facial. MÉTODOS: foram selecionadas 176 crianças na fase de dentição decídua completa. Exames clínicos intra- e extrabucais foram realizados, e um questionário, com aspectos relacionados aos hábitos de sucção não nutritiva, foi aplicado aos responsáveis. RESULTADOS: encontrou-se uma relação estatisticamente significativa entre as variáveis hábito de sucção não nutritiva e MAA. Entretanto, não houve associação desses fatores com a morfologia facial da criança. CONCLUSÃO: a presença dos hábitos de sucção não nutritiva tem associação para a determinação da má oclusão de MAA, independentemente do padrão facial morfológico na dentição decídua. .

Stress distribution in human zygomatic pillar using three-dimensional finite element analysis / Distribución de la tensión en el pilar cigomático humano usando análisis de elementos finitos tridimensional

This paper aimed to analyze stress distribution in human zygomatic pillar during masseter muscle contraction using three-dimensional finite element analysis. A three-dimensional model and hemi facial skull were produced based on CT-scan data. An adult male skull with structural anatomy integrity was used as model. Muscles forces were applied at origin of elevator muscles and supports was applied at the occlusal surfaces at first and second molars to simulate a masticatory load and stimulate the zygomatic pillar. Supports were applied to the occlusal contacts. Symmetry conditions were placed at the mid-sagittal plane. For the top and back cutting plane, constraints were used. Equivalent Von-Mises Stress and Maximum Principal Stress analysis were performed from the stress fields along the zygomatic pillar. It was represented by stress concentration at the alveolar process, zygomatic bone, frontal and temporal process of zygomatic bone and superciliary arch. Stress line indicates distribution of stress from maxilla toward the frontal and temporal bone. The stresses occurred due to resultant occlusal forces is mainly supported by the zygomatic bone, non-uniformly distributed and predominantly through the zygomatic pillar. This study contributed to better understanding of stress distribution in zygomatic pillar to understand the influence of chewing on zygomatic pillar morphology and also be useful for clinical practice.

El objetivo de este artículo fue analizar la distribución de la tensión en el pilar cigomático humano durante la contracción del músculo masetero utilizando análisis de elementos finitos tridimensionales. Un modelo de tres dimensiones de dientes del hemicráneo facial fueron producidos sobre la base de datos de CT-scan. Se utilizó como modelo un cráneo adulto de sexo masculino con la integridad de la anatomía estructural. Fuerzas musculares se aplicaron en el origen de los ascensores de los músculos de la mandíbula y soportes se aplicaron a la superficie oclusal del primer y segundo molar para simular una carga masticatoria y estimular el pilar cigomático. Condiciones de simetría se colocaron en el plano mediano. Se utilizaron restricciones en los planos superior y posterior. El análisis de las tensiones equivalentes von-Mises y máximo director se realizó a través del campo de esfuerzos a lo largo del pilar cigomático. Fue representada la concentración de esfuerzos en el proceso alveolar, hueso cigomático, proceso frontal y temporal del hueso cigomático y el arco superciliar. La línea de tensión indica la distribución de la tensión del maxilar hacia el hueso frontal y temporal. Las tensiones se produjeron debido a las fuerzas oclusales resultantes, que se apoyan principalmente por el hueso cigomático, distribuidas de manera no uniforme y sobre todo a través del pilar cigomático. Este estudio ha contribuido a una mejor comprensión de la distribución de la tensión en el pilar cigomático para entender la influencia de la masticación sobre la morfología de este pilar y ser de utilidad en la práctica clínica.

Cone beam tomographic study of facial structures characteristics at rest and wide smile, and their correlation with the facial types

OBJECTIVE: To determine the characteristics of facial soft tissues at rest and wide smile, and their possible relation to the facial type. METHODS: We analyzed a sample of forty-eight young female adults, aged between 10, 19 and 40 years old, with a mean age of 30.9 years, who had balanced profile and passive lip seal. Cone beam computed tomographies were performed at rest and wide smile postures on the entire sample which was divided into three groups according to individual facial types. Soft tissue features analysis of the lips, nose, zygoma and chin were done in sagittal, axial and frontal axis tomographic views. RESULTS: No differences were observed in any of the facial type variables for the static analysis of facial structures at both rest and wide smile postures. Dynamic analysis showed that brachifacial types are more sensitive to movement, presenting greater sagittal lip contraction. However, the lip movement produced by this type of face results in a narrow smile, with smaller tooth exposure area when compared with other facial types. CONCLUSION: Findings pointed out that the position of the upper lip should be ahead of the lower lip, and the latter, ahead of the pogonion. It was also found that the facial type does not impact the positioning of these structures. Additionally, the use of cone beam computed tomography may be a valuable method to study craniofacial features.

OBJETIVOS: determinar as características dos tecidos moles faciais nas fases em repouso e em sorriso amplo, e sua possível relação com o tipo facial. MÉTODOS: foi analisada uma amostra de 48 adultos jovens, com idade variando entre 19,10 e 40 anos, com média de 30,9 anos, do sexo feminino, apresentando faces equilibradas e selamento labial passivo. Tomografias computadorizadas de feixe cônico em repouso e em sorriso amplo foram efetuadas em toda a amostra, que foi segmentada em três grupos de acordo com o tipo facial. A análise das características tegumentares de lábios, nariz, malar e mento foi feita em cortes tomográficos sagitais, axiais e em vista frontal. RESULTADOS: na análise estática das estruturas faciais, em repouso e em sorriso amplo, não houve diferenciação entre os tipos faciais em nenhuma das variáveis estudadas. A análise dinâmica evidenciou que o tipo braquifacial é mais sensível à movimentação, apresentando maior contração sagital do lábio superior, porém, o deslocamento labial apresentado por esse tipo facial produz um sorriso pouco amplo, com menor área de exposição dentária quando comparado aos demais tipos faciais. CONCLUSÃO: constatou-se que, em uma face equilibrada, a posição do lábio superior deve ser à frente do lábio inferior, e esse à frente do pogônio, e que o tipo facial não exerce influência sobre o posicionamento dessas estruturas. Observamos que a utilização de tomografias computadorizadas de feixe cônico pode ser de grande valia para o estudo de características craniofaciais.

Análisis morfométrico de los reparos anatómicos involucrados en la técnica quirúrgica de colocación de implantes cigomáticos / Morphometric analysis of anatomic landmarks involved in surgical technique of zygomatic implants placement

El objetivo de esta investigación fue ofrecer datos morfométricos de las estructuras óseas involucradas en la técnica quirúrgica de colocación de implantes cigomáticos, proveyendo así, informaciones que faciliten la planificación y realización de dicho procedimiento. Considerando los valores promedios obtenidos en nuestro estudio, concluimos que el mayor espesor del hueso cigomático se encuentra en la zona media del hueso. Sugerimos que el anclaje superior del implante cigomático no debe extenderse hasta el margen posterosuperior del hueso cigomático, ya que el espesor del hueso a este nivel no ofrece condiciones de adecuada oseointegración de implantes.

The aim of this study is to provide morphometric data of bony structures involved in the surgical technique of zygomatic implants, thus providing information to facilitate the planning and implementation of this procedure. Considering the average values obtained in our study, we conclude that the greatest thickness of the zygomatic bone is in the middle of the bone. We suggest that the upper anchorage of zygomatic implants should not extend to the posterior margin of the zygomatic bone, since the bone thickness at this level does not offer suitable conditions for osseointegration of implants.

Reabilitação de maxilas atróficas com implantes zigomáticos em carga imediata: estudo retrospectivo de 22 casos / Rehabilitation of atrophic maxilla with immediate loading through zigomatic implants: review of 22 cases

Realizou-se uma análise retrospectiva de 22 casos de maxilas atróficas, reabilitadas proteticamente com carga imediata, por meio de implantes cônicos na região anterior de maxila em conjunto com dois implantes zigomáticos bilateralmente. Objetivamos discutir a efetividade deste método a partir de informações relativas à técnica empregada (tipo de implante, quantidade, comprimento e torque de inserção) e da taxa de sucesso durante o tempo de acompanhamento da pesquisa. Os pacientes apresentaram-se com média de idade de 57,3 anos, variando de 39 a 76, sendo 6 do gênero masculino e 16 feminino. A média do torque de inserção foi de 47,75N.cm para os implantes cônicos anteriores (n = 68) e de 68,5N. cm para os zigomáticos (n = 44), ambos apresentaram taxa de sucesso de 100% durante o período de acompanhamento médio de 34,7 meses

The present study evaluated retrospectively 22 atrophic maxilla cases treated by prosthodontic rehabilitation with immediate loading using conic implants in the pre-maxilla with two zigomatic implants bilaterally disposed. We aimed at discussing the effectiveness of this treatment through information on the applied method (type of implant, quantity, length and placement torch) and on the success rate during follow-up period. The average age of the patients was 57.3 years old, varying from 39 to 76 and six of them were males and sixteen females. The insertion torch average was of 47.75N.cm for anterior conic implants (n = 68) and 68.5Ncm on the right and left zigomatic implants (n = 44), both with success rate of 100% during a 34.7 months follow-up period

Role of buccal corridor in smile esthetics and its correlation with underlying skeletal and dental structures.

Purpose: This study was designed to evaluate the buccal corridor in smile esthetics and to correlate it with underlying hard tissues. Materials and Methods: Posed smiling frontal photographs, digital posterior-anterior (PA) cephalograms, and study models of 25 males and 25 females in age range of 18-25 years were taken. Photographs were evaluated for smile esthetics by eight orthodontists, eight plastic surgeons, eight beauticians and eight lay people to group them into three groups with least attractive, average and attractive smile and buccal corridor width was measured. Digital PA cephalograms were transferred on Nemo-tech software for frontal facial analysis. Intercanine and intermolar widths were measured on upper study model with the help of a digital calliper. Results: The buccal corridor width was least in attractive smile group and maximum in least attractive smile group. The buccal corridor width had a negligible correlation with hard tissues and a mild to moderate inverse correlation with intercanine and intermolar widths within the groups. Conclusion: As the amount of buccal corridor display was increased, smiling images were scored less attractive by the evaluators. The buccal corridor is not influenced by underlying skeletal hard tissues but have mild to moderate inverse correlation with the intercanine and intermolar width.

Abordaje transcigomático: aspectos técnicos y utilidad / Transzygomatic approach: technical aspects & utility

Objetivo: describir los detalles técnicos del abordaje transcigomático, mostrando su utilidad. Descripción: la incisión se extiende desde el borde inferior del arco cigomático hasta la línea pupilar contralateral. Luego se realiza una disección subgaleal e interfascial. Posteriormente, el arco cigomático es seccionado en forma vertical en dos sectores, y luego movilizado inferiormente junto con el músculo masetero. El paso siguiente es realizar craneotomía fronto-temporo-esfenoidal, de tal manera que la parte anterior de la duramadre temporal quede totalmente expuesta. Así las posibilidades quirúrgicas son las siguientes: a) acceso intradural a la fosa media; b) acceso intradural pretemporal a las cisternas basales; c) acceso intradural transtemporal y d) acceso extradural a la fosa media. Conclusión: el abordaje transcigomático ofrece una excelente exposición al piso de la fosa media y a la pared lateral del seno avernoso (tanto intradural como extradural). Además, combinando con una vía pretemporal, permite un muy buen acceso a la cisterna.

Anatomia aplicada do ramo temporal do nervo facial: estudo do risco potencial de lesão durante a cirurgia do rejuvenescimento facial / Applied anatomy of the branch of the facial nerve: study of the potential risk of injury during facial rejuvenation surgery

Introdução: O ramo temporal do nervo facial é um dos nervos mais comumente lesados, devido à pouca tela subcutânea que o protege a partir da sua saída da glândula parótida. Método: Vinte e cinco hemifaces de cadáveres foram dissecadas e analisadas as relações entre o ramo temporal e glândula parótida, arco zigomático, SMAS, artéria temporal superficial e músculo frontal. Resultados: Doze ramos temporais dissecados perderam a proteção da glândula parótida a uma distância de 1,7 cm anterior ao trago. O cruzamentodo arco zigomático por dois ramos temporais foi o mais frequente. A passagem pelo arco zigomático ocorreu entre 3,2 e 3,9 cm posteriores à borda lateral da órbita. O curso do ramo temporal junto às faces profundas do SMAS e da fáscia temporoparietal, e acima da lâmina superficial da fáscia temporal profunda foi constante. O ramo frontal da artéria temporal superficial foi superior e sua trajetória paralela ao ramo temporal em 92% das dissecções. Conclusão: O ramo temporal do nervo facial segue um plano constante ao longo da face profunda da fáscia temporoparietal e está muito superficial quando cruza o arco zigomático.

Background: The temporal branch of the facial nerve is one of the nerves more commonly injured due to the scarce subcutaneous tissue that protects it from its exit at the parotid gland. Method: Twenty five cadaveric hemifaces were dissected allowing a analysis of the temporal branch and: parotid gland, zygomatic arch, SMAS, superficial temporal artery and frontal muscle. Results: Twelve temporal branches exposed at a distance 1.7cm anterior to the trago. Two temporal branches crossing the zygomatic arc was the most frequent finding. This passage occurred between 3.2 to 3.9 cm posterior to the lateral border of the orbit. The trajectory of the temporal branch near the deep side of the SMAS and temporofacial fascia and above the superficial layer of the deep temporal fascia was constant. The frontal branch of the superficial temporal artery was superior and parallel to the nerve trajectory in 92% of the dissections Conclusion: The temporal branch follow a constant plane along the under surface of the temporoparietal fascia and is quite superficial as it cross the zygomatic arch.

Anatomical Consideration of the Anterior and Lateral Cutaneous Nerves in the Scalp

To better understand the anatomic location of scalp nerves involved in various neurosurgical procedures, including awake surgery and neuropathic pain control, a total of 30 anterolateral scalp cutaneous nerves were examined in Korean adult cadavers. The dissection was performed from the distal to the proximal aspects of the nerve. Considering the external bony landmarks, each reference point was defined for all measurements. The supraorbital nerve arose from the supraorbital notch or supraorbital foramen 29 mm lateral to the midline (range, 25-33 mm) and 5 mm below the supraorbital upper margin (range, 4-6 mm). The supratrochlear nerve exited from the orbital rim 16 mm lateral to the midline (range, 12-21 mm) and 7 mm below the supraorbital upper margin (range, 6-9 mm). The zygomaticotemporal nerve pierced the deep temporalis fascia 10 mm posterior to the frontozygomatic suture (range, 7-13 mm) and 22 mm above the upper margin of the zygomatic arch (range, 15-27 mm). In addition, three types of zygomaticotemporal nerve branches were found. Considering the superficial temporal artery, the auriculotemporal nerve was mostly located superficial or posterior to the artery (80%). There were no significant differences between the right and left sides or based on gender (P>0.05). These data can be applied to many neurosurgical diagnostic or therapeutic procedures related to anterolateral scalp cutaneous nerve.