Study on the method of automatically determining maxillary complex landmarks based on non-rigid registration algorithms / 中华口腔医学杂志

Objective: To explore an automatic landmarking method for anatomical landmarks in the three-dimensional (3D) data of the maxillary complex and preliminarily evaluate its reproducibility and accuracy. Methods: From June 2021 to December 2022, spiral CT data of 31 patients with relatively normal craniofacial morphology were selected from those who visited the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology. The sample included 15 males and 16 females, with the age of (33.3±8.3) years. The maxillary complex was reconstructed in 3D using Mimics software, and the resulting 3D data of the maxillary complex was mesh-refined using Geomagic software. Two attending physicians and one associate chief physician manually landmarked the 31 maxillary complex datasets, determining 24 anatomical landmarks. The average values of the three expert landmarking results were used as the expert-defined landmarks. One case that conformed to the average 3D morphological characteristics of healthy individuals' craniofacial bones was selected as the template data, while the remaining 30 cases were used as target data. The open-source MeshMonk program (a non-rigid registration algorithm) was used to perform an initial alignment of the template and target data based on 4 landmarks (nasion, left and right zygomatic arch prominence, and anterior nasal spine). The template data was then deformed to the shape of the target data using a non-rigid registration algorithm, resulting in the deformed template data. Based on the unchanged index property of homonymous landmarks before and after deformation of the template data, the coordinates of each landmark in the deformed template data were automatically retrieved as the automatic landmarking coordinates of the homonymous landmarks in the target data, thus completing the automatic landmarking process. The automatic landmarking process for the 30 target data was repeated three times. The root-mean-square distance (RMSD) of the dense corresponding point pairs (approximately 25 000 pairs) between the deformed template data and the target data was calculated as the deformation error of the non-rigid registration algorithm, and the intra-class correlation coefficient (ICC) of the deformation error in the three repetitions was analyzed. The linear distances between the automatic landmarking results and the expert-defined landmarks for the 24 anatomical landmarks were calculated as the automatic landmarking errors, and the ICC values of the 3D coordinates in the three automatic landmarking repetitions were analyzed. Results: The average three-dimensional deviation (RMSD) between the deformed template data and the corresponding target data for the 30 cases was (0.70±0.09) mm, with an ICC value of 1.00 for the deformation error in the three repetitions of the non-rigid registration algorithm. The average automatic landmarking error for the 24 anatomical landmarks was (1.86±0.30) mm, with the smallest error at the anterior nasal spine (0.65±0.24) mm and the largest error at the left oribital (3.27±2.28) mm. The ICC values for the 3D coordinates in the three automatic landmarking repetitions were all 1.00. Conclusions: This study established an automatic landmarking method for three-dimensional data of the maxillary complex based on a non-rigid registration algorithm. The accuracy and repeatability of this method for landmarking normal maxillary complex 3D data were relatively good.

Automatic determination of mandibular landmarks based on three-dimensional mandibular average model / 北京大学学报(医学版)

OBJECTIVE@#To explore an efficient and automatic method for determining the anatomical landmarks of three-dimensional(3D) mandibular data, and to preliminarily evaluate the performance of the method.@*METHODS@#The CT data of 40 patients with normal craniofacial morphology were collected (among them, 30 cases were used to establish the 3D mandibular average model, and 10 cases were used as test datasets to validate the performance of this method in determining the mandibular landmarks), and the 3D mandibular data were reconstructed in Mimics software. Among the 40 cases of mandibular data after the 3D reconstruction, 30 cases that were more similar to the mean value of Chinese mandibular features were selected, and the size of the mandibular data of 30 cases was normalized based on the Procrustes analysis algorithm in MATLAB software. Then, in the Geomagic Wrap software, the 3D mandibular average shape model of the above 30 mandibular data was constructed. Through symmetry processing, curvature sampling, index marking and other processing procedures, a 3D mandible structured template with 18 996 semi-landmarks and 19 indexed mandibular anatomical landmarks were constructed. The open source non-rigid registration algorithm program Meshmonk was used to match the 3D mandible template constructed above with the tested patient's 3D mandible data through non-rigid deformation, and 19 anatomical landmark positions of the patient's 3D mandible data were obtained. The accuracy of the research method was evaluated by comparing the distance error of the landmarks manually marked by stomatological experts with the landmarks marked by the method of this research.@*RESULTS@#The method of this study was applied to the data of 10 patients with normal mandibular morphology. The average distance error of 19 landmarks was 1.42 mm, of which the minimum errors were the apex of the coracoid process [right: (1.01±0.44) mm; left: (0.56±0.14) mm] and maximum errors were the anterior edge of the lowest point of anterior ramus [right: (2.52±0.95) mm; left: (2.57±1.10) mm], the average distance error of the midline landmarks was (1.15±0.60) mm, and the average distance error of the bilateral landmarks was (1.51±0.67) mm.@*CONCLUSION@#The automatic determination method of 3D mandibular anatomical landmarks based on 3D mandibular average shape model and non-rigid registration algorithm established in this study can effectively improve the efficiency of automatic labeling of 3D mandibular data features. The automatic determination of anatomical landmarks can basically meet the needs of oral clinical applications, and the labeling effect of deformed mandible data needs to be further tested.

The slant of the forehead as a craniofacial feature of impulsiveness

Objective: Impulsiveness has been the subject of much research, but little is known about the possible relationship between craniofacial anatomy and impulsiveness. The present study was designed to investigate the relationship between one aspect of craniofacial structure (the angle of inclination of the forehead) and impulsiveness. Method: Photographs in profile were obtained from 131 volunteers who had been fined for driving at high speed and were undergoing a court-mandated driving license point-recovery course. They completed the Barratt Impulsiveness Scale (BIS-11), the Impulsive Behavior Scale (UPPS-P), and Zuckerman's Sensation Seeking Scale (V). The angle of the slant of the forehead was measured with a photographic support and a protractor. Results: High positive concordance was found between forehead inclination and 14 out of the 15 impulsiveness factors studied. Conclusions: The angle of inclination of the forehead was significantly associated with self-reported impulsiveness in this sample of traffic violators.

Evaluation of the rapid and slow maxillary expansion using cone-beam computed tomography: a randomized clinical trial

ABSTRACT OBJECTIVE: The aim of this randomized clinical trial was to evaluate the dental, dentoalveolar, and skeletal changes occurring right after the rapid maxillary expansion (RME) and slow maxillary expansion (SME) treatment using Haas-type expander. METHODS: All subjects performed cone-beam computed tomography (CBCT) before installation of expanders (T1) and right after screw stabilization (T2). Patients who did not follow the research parameters were excluded. The final sample resulted in 21 patients in RME group (mean age of 8.43 years) and 16 patients in SME group (mean age of 8.70 years). Based on the skewness and kurtosis statistics, the variables were judged to be normally distributed and paired t-test and student t-test were performed at significance level of 5%. RESULTS: Intermolar angle changed significantly due to treatment and RME showed greater buccal tipping than SME. RME showed significant changes in other four measurements due to treatment: maxilla moved forward and mandible showed backward rotation and, at transversal level both skeletal and dentoalveolar showed significant changes due to maxillary expansion. SME showed significant dentoalveolar changes due to maxillary expansion. CONCLUSIONS: Only intermolar angle showed significant difference between the two modalities of maxillary expansion with greater buccal tipping for RME. Also, RME produced skeletal maxillary expansion and SME did not. Both maxillary expansion modalities were efficient to promote transversal gain at dentoalveolar level. Sagittal and vertical measurements did not show differences between groups, but RME promoted a forward movement of the maxilla and backward rotation of the mandible.

RESUMO OBJETIVO: o objetivo do presente ensaio clínico randomizado foi avaliar as transformações dentárias, dentoalveolares e ósseas que ocorrem imediatamente após o tratamento com expansão rápida da maxila (ERM) e lenta (ELM) usando expansores do tipo Haas. MÉTODOS: todos os indivíduos foram submetidos a tomografias computadorizadas de feixe cônico (TCFC) antes da colocação dos expansores (T1) e imediatamente após a estabilização do parafuso (T2). Os pacientes que não seguiram os parâmetros da pesquisa foram excluídos. A amostra final constou de 21 pacientes no grupo ERM (idade média de 8,43 anos) e 16 no grupo ELM (idade média de 8,7 anos). Com base em estatística de assimetria e curtose, as variáveis foram consideradas de distribuição normal, e os testes t pareado e t de Student foram realizados, com nível de significância de 5%. RESULTADOS: o ângulo intermolares mudou significativamente devido ao tratamento, e o grupo ERM apresentou maior inclinação vestibular do que o grupo ELM. O grupo ERM mostrou alterações significativas em outras quatro medidas devido ao tratamento: a maxila apresentou deslocamento anterior e a mandíbula, rotação posterior; no nível transversal, houve tanto alterações ósseas quanto dentoalveolares significativas, devido à expansão maxilar. O grupo ELM apresentou alterações significativas devido à expansão maxilar. CONCLUSÕES: apenas o ângulo intermolares apresentou diferença significativa entre as duas modalidades de expansão maxilar, com maior inclinação vestibular no grupo ERM. A ERM resultou, também, em expansão maxilar óssea, ao contrário da ELM. As duas modalidades de expansão maxilar promoveram, de forma eficiente, um ganho transversal em nível dentoalveolar. As medidas sagitais e verticais não apresentaram diferenças entre os grupos, mas a ERM promoveu o deslocamento anterior da maxila e a rotação posterior da mandíbula.

Is the omega sign a reliable landmark for the neurosurgical team? An anatomical study about the central sulcus region / O sinal do ômega é um reparo anatômico confiável para a equipe neurocirúrgica? Estudo anatômico sobre a regiāo do sulco central

ABSTRACTThe central sulcus region is an eloquent area situated between the frontal and parietal lobes. During neurosurgical procedures, it is sometimes difficult to understand the cortical anatomy of this region.Objective Find alternative ways to anatomically navigate in this region during neurosurgical procedures.Method We analyzed eighty two human hemispheres using a surgical microscope and completed a review of the literature about central sulcus region.Results In 68/82 hemispheres, the central sulcus did not reach the posterior ramus of the lateral sulcus. A knob on the second curve of the precentral gyrus was reliably identified in only 64/82 hemispheres.Conclusion The morphometric data presented in this article can be useful as supplementary method to identify the central sulcus region landmarks.

RESUMOA região do sulco central é uma área eloquente posicionada entre os lobos frontal e parietal. Durante procedimentos neurocirúrgicos, em algumas ocasiões, torna-se difícil compreender a anatomia cortical desta região.Objetivo Encontrar métodos alternativos para uma navegaçāo anatômica desta regiāo durante procedimentos neurocirúrgicos.Método Analisamos oitenta e dois hemisférios humanos usando um microscópio cirúrgico, além de fazer uma revisão da literatura.Resultados Em 68/82 hemisférios, o sulco central não atingiu o ramo posterior do sulco lateral. Uma dilatação na segunda curva do giro precentral foi encontrada em apenas 64/82 hemisférios.Conclusão Os dados morfométricos apresentados neste artigo podem ser úteis como método suplementar para identificação dos reparos anatômicos na região do sulco central.

Photographs for anthropometric measurements of the breast region. Are there limitations?

PURPOSE: To determine the limitations of the photographs used to obtain the anthropometric measurements of the breast region. METHODS: Five women, between the ages of 18 to 60 years, were evaluated. Photographs of the frontal and left and right profile views of their breasts were taken. Based on the current literature, the most commonly used anthropometric and anatomic landmarks for breast measurement were marked in their different positions. The different points were used to evaluate if the direct anthropometry was possible in a standardized way and determine how the points and the positions can to be used in any breast measurements. RESULTS: There were some limitations to the use of defining points of the breast fold, as well as of its lower portion and lateral extension positions in both profiles. CONCLUSION: The defining points of the breast fold and the profile photographs have some limitations and we suggested how the points and positions can be used for breasts measurements. .

Morphology and location of surface landmarks of foramen ovale in Kenyans / Morfología y ubicación de puntos anatómicos de superficie del foramen oval en kenianos

Foramen ovale is a surgically important aperture of the skull since it allows approach to and manipulation of the trigeminal ganglion as it lies in the Meckel's cave. This transfacial approach, Hartel's approach, requires two anatomical points for accurate cannulation; the zygomatic point and the pupil point. This study describes the morphology and location of foramen ovale and describes the pupil point in relation to the medial canthus in the Kenyan population. Department of Human Anatomy departmental review board approved the study. Two hundred dry skulls from the Department of Human Anatomy were studied using a digital calliper with help of a measuring frame. The results were analysed using SPSS version 20. The results showed the length and width of right foramen ovale was 7.69 mm mean (SD ±1.31) and 4.24 mm (±0.64) respectively while the left foramen ovale was 7.68 mm (±1.23) and 4.28 mm (±0.74). The distance of the zygomatic point from the external auditory meatus on the right was 23.54 mm (±2.26) and the left was 23.49 mm (±2.16). The median distances of the pupil point in relation to the medial canthus was 9.5mm on the right and 8.1 mm on the left. These results were significantly different from other population data. Neuronavigational aids to foramen ovale in Kenyans should take this into consideration.

El foramen oval es una abertura quirúrgicamente importante del cráneo, que permite el enfoque y manipulación del ganglio trigeminal ya que se encuentra en la impresión trigeminal (fosita de Meckel). Este enfoque transfacial, el enfoque de Hartel, requiere dos puntos anatómicos para la canalización precisa; el punto cigomático y el punto de la pupila. Este estudio describe la morfología y la ubicación del foramen oval, y el punto pupilar en relación al canto medial en la población de Kenia. La junta directiva del Departamento de Anatomía Humana aprobó el estudio. Doscientos cráneos secos procedentes del Departamento de Anatomía Humana se estudiaron utilizando un caliper digital con ayuda de un marco de medición. Los resultados fueron analizados mediante el programa SPSS versión 20. Los resultados mostraron que la longitud y ancho del foramen oval derecho fue de 7,69 mm media (±1,31) y 4,24 mm (±0,64), respectivamente, mientras que el foramen oval izquierdoo fue de 7,68 mm (±1,23) y 4,28 mm (±0,74). La distancia del punto cigomático desde el meato acústico externo derecho fue 23,54 mm (±2,26) y el izquierdo de 23,49 mm (±2,16). Las distancias promedios del punto de la pupila en relación con el canto medial fueron de 9,5 mm (el derecha) y 8,1 mm (el izquierdo). Estos resultados fueron significativamente diferentes de otros datos demográficos. El apoyo para la neuronavegación para acceder al foramen oval en kenianos debe tener esto en consideración.

The localization of the asterion according to the anatomical landmarks of posterior cranial fossa in newborns: clinical implications / Localización del asterión de acuerdo con los puntos anatómicos de la fosa craneal posterior en recién nacidos: implicaciones clínicas

The purpose of this study was to determine the localization of the asterion according to the anatomical landmarks of posterior cranial fossa and its relation with sinuses for posterolateral surgical approaches in newborns. On 70 head-halves, a needle about 2 mm with diameter was placed on the centre point of asterion (posterolateral fontanel) by inserting into the whole cranial bony tissue by forming an right angle with the bony surface. Various localizations of asterion and its measurements from the internal and external anatomical landmarks were investigated on term neonatal cadavers. The localization of asterion was found as on the sigmoid-transverse sinus junction (STJ) (5., 6., 7., 8. squares) in 40% of cases on right side and in 34%, on left side. Additionally, it was located below the STJ (9., 10., 11., 12. squares) in 60% of cases, on right side and in 63% of cases on left side. We determined that the most frequent localization of asterion as the 11. square both for the right and left sides 12 (34%) cases for the right side and 11 (31,4%) cases for the left side. The asterion was not located on 1., 2., 3., 4., 5. and 12. squares on right side and 1., 3., 4., 8. and 9. squares on left side. It has been found that the region of asterion has an average distance value of 19.9 mm to internal acoustic meatus (MI), 31.7 mm to posterior clinoid process (PC), 34.4 to dorsum sellae (DS), 19.2 mm to jugular foramen (FJ), 23.0 mm to hypoglossal canal (HC), internally. The distance of asterion as 28.8 mm to zygoma root (ZR) and 22.3 mm to Henle's spine (HS) and 15.8 mm to mastoid tip (MT) and 35.9 mm to external occipital protuberance (PE) were observed. By the guide of point asterion on newborns the area of 1cm2 on this point which was placed on superior 4 squares of our scale diagram is suggested as a safe area of placement of first burr hole to avoid from the risk of bleeding of sigmoid and transverse sinuses on craniotomies of posterior fossa.

El propósito de este estudio fue determinar la localización del asterion de acuerdo con los puntos anatómicos de la fosa craneal posterior y su relación con los senos de abordajes quirúrgicos posterolaterales en los recién nacidos. Fueron utilizadas 70 hemicabezas y se colocó una aguja de alrededor de 2 mm de diámetro en el punto central del asterion (fontanela posterolateral) en todo el tejido óseo craneal produciéndose la formación de un ángulo recto con la superficie ósea. La localización del asterion y las mediciones de los puntos de referencia anatómicos internos y externos fueron investigados en cadáveres de neonatos a término. La localización del asterion se encontró en la unión sinusal transverso sigmoide (STJ) (cuadrados 5., 6., 7., 8.) en el 40% de los casos en el lado derecho y en el 34%, en el lado izquierdo. Además, se encontró por debajo del STJ (cuadrados 9., 10., 11., 12.) en un 60% de los casos en el lado derecho y en el 63% de los casos en el lado izquierdo. Se determinó que la localización más frecuente del asterion fue 11., tanto para los lados derecho e izquierdo, 12 casos (34%) para el lado derecho y 11 casos (31,4%) para el lado izquierdo. El asterion no se encuentra en los cuadrados 1., 2., 3., 4., 5. y 12. del lado derecho y 1., 3., 4., 8. y 9. del lado izquierdo. Se determinó que la región del asterion tiene una distancia promedio de 19,9 mm al meato acústico interno, 31,7 mm al proceso clinoides posterior, 34,4 mm al dorso selar, 19,2 mm al foramen yugular y 23,0 mm al canal hipogloso, internamente. La distancia del asterion a la raíz del hueso cigomático fue 28,8 mm y 22,3 mm a la columna vertebral, siendo de 15,8 mm al proceso mastoides y 35,9 mm a la protuberancia occipital externa. En los recién nacidos, se sugiere un área de 1cm2 y se colocan en 4 casillas superiores de nuestro diagrama a escala, como una zona segura para la realización de la primera trepanación para evitar el riesgo de sangrado de los senos sigmoide y transverso en craneotomías de fosa posterior.

Desplazamiento de los puntos de referencia craneales utilizados en los análisis cefalométrico de jarabak y ricketts, durante el crecimiento activo / Displacement of cranial reference landmarks used in jarabak and ricketts cephalometric analysis during active growth

El objetivo de este trabajo fue evaluar el desplazamiento de los puntos craneales: Nasion, Silla, Basion, Porion, Orbitario y Pterigoideo, utilizados como referencia en los análisis cefalométricos de Jarabak y Ricketts durante el crecimiento activo. Se seleccionaron 120 telerradiografías de perfil en formato digital, correspondientes a 60 pacientes con 2 telerradiografías cada uno, tomadas con un intervalo de tiempo mínimo de 1 año (T1 y T2), en donde T1 se encuentra antes o durante el peak de crecimiento según el Estado de Maduración Cervical Vertebral (CVM) I, II ó III de Baccetti y T2 en estadio CVM IV,V,VI (después del peak de crecimiento). Un examinador previamente calibrado, ubicó los puntos analizados y para evaluar su desplazamiento, se realizaron mediciones en T1 y T2 (3 variables para cada punto), usando como referencia 2 planos que no se modifican a partir de los 5 años de edad (LCB y Vert-T). Para determinar el desplazamiento de los puntos, se calculó la variación promedio observada entre T1 y T2 y se realizó la prueba t para muestras pareadas o Wilcoxon (según distribución) para determinar la existencia de diferencias significativas. Además, se comparó la muestra por sexo, CVM inicial y CVM final. Se encontraron variaciones entre T1 y T2 en todas las medidas, aunque sólo en 5 de ellas se encontraron diferencias significativas; no se encontró diferencias al comparar por sexo, CVM inicial y final. Es así como podemos concluir que todos los puntos craneales analizados sufren desplazamiento durante el crecimiento. Los puntos Basion y Orbitario son los que sufren mayor desplazamiento. Es necesario analizar las implicancias de estas variaciones en los resultados obtenidos de los análisis cefalométrico y evaluar la necesidad de utilizar puntos de referencia alternativos.

The objective of this study was to evaluate the displacement of cranial reference points: Nasion, Sella, Basion, Porion, Orbitale and Pterygomaxillary, used in Jarabak and Ricketts cephalometric analysis, during active growth. Hundred and twenty digitalized lateral telerradiographies, corresponding to 60 patients (2 teleradiographies each one), were collected. The radiographies were taken with a minimum interval of one year between them (T1 and T2), where T1 is taken before or during the pubertal growth peack according to the cervical vertebral maturation stages developed by baccetti (CVM) I, II or III and T2 in CVM IV,V,VI (after the growth peak). Then, a previously calibrated examinator marked reference points and cephalometric measurements were taken (2 variables for each landmark). Measurements were made using craniofacial stable structures as references (stable basicranial line and Vertical T). To detect displacement in the landmark positions, t test or Wilcoxon test according to the distribution of each variable, was used to compare the data between T1 and T2. Also, comparisons were made by sex, and by initial and final CVM. All of the variables have variations between T1 y T2, but only 5 have a statistically significant difference. There were no differences between sexes and at initial and final CVM. In conclusion, all of the reference landmarks analyzed had displacement during active growth. Point Basion and Orbitale suffered the largest displacement. It is necessary to analyze the clinical implications of this displacement in order to evaluate the convenience of using alternative reference landmarks.

Facial height in Japanese-Brazilian descendants with normal occlusion

OBJECTIVE: The aim of this study was to determine the standards of facial height in 30 young (14-year-old) Japanese-Brazilian descendants with normal occlusion, and assess whether sexual dimorphism is evident. METHODS: The cephalometric measurements used followed the analyses by Wylie-Johnson, Siriwat-Jarabak, Gebeck, Merrifield and Horn. RESULTS: Results showed dimorphism for total anterior facial height (TAFH), lower anterior facial height (LAFH), anterior facial height (AFH), total posterior facial height (TPFH) and upper posterior facial height (UPFH) measurements. CONCLUSIONS: The standards of facial heights in young Japanese-Brazilian descendants with normal occlusion were observed. Sexual dimorphism was identified in five out of thirteen evaluated variables at this age range. .

INTRODUÇÃO: o objetivo desse estudo foi obter os valores médios de normalidade das alturas faciais anterior e posterior de 30 jovens mestiços nipo-brasileiros, descendentes de xantodermas e leucodermas, com oclusão normal, com idade média de 14 anos, e verificar a presença ou ausência de dimorfismo entre os sexos. MÉTODOS: elaborou-se um estudo cefalométrico com as mensurações advindas das análises de Wylie e Johnson, Siriwat e Jarabak, Gebeck, Merrifield e Horn. RESULTADOS: os resultados revelaram a presença de dimorfismo entre os sexos para as variáveis AFAT, AFAI, AFA, AFPT e AFPS. CONCLUSÕES: um padrão cefalométrico específico, das alturas faciais anterior e posterior, para os jovens mestiços nipo-brasileiros com oclusão normal, descendentes de xantodermas e leucodermas, foi apresentado e um dimorfismo entre os sexos para cinco das treze variáveis avaliadas foi verificado nessa faixa etária média. .

Determining shapes and dimensions of dental arches for the use of straight-wire arches in lingual technique

INTRODUCTION: This study aims to determine the shape and dimension of dental arches from a lingual perspective, and determine shape and size of a straight archwire used for lingual Orthodontics. METHODS: The study sample comprised 70 Caucasian Brazilian individuals with normal occlusion and at least four of Andrew's six keys. Maxillary and mandibular dental casts were digitized (3D) and the images were analyzed by Delcam Power SHAPET 2010 software. Landmarks on the lingual surface of teeth were selected and 14 measurements were calculated to determine the shape and size of dental arches. RESULTS: Shapiro-Wilk test determined small arch shape by means of 25th percentile (P25%) - an average percentile for the medium arch; and a large one determined by means of 75th percentile (P75%). T-test revealed differences between males and females in the size of 12 dental arches. CONCLUSION: The straight-wire arch shape used in the lingual straight wire technique is a parabolic-shaped arch, slightly flattened on its anterior portion. Due to similarity among dental arch sizes shown by males and females, a more simplified diagram chart was designed. .

INTRODUÇÃO: esse estudo objetiva encontrar a forma e dimensão de arcadas dentária para definir a forma de um arco contínuo que possa ser utilizado na técnica lingual. MÉTODOS: a amostra foi composta por indivíduos brasileiros, leucodermas, com oclusão normal natural, que apresentaram, no mínimo, quatro das seis chaves de oclusão de Andrews. Os modelos das arcadas dentárias superior e inferior foram digitalizados (3D) e as imagens exportadas para o software Delcam Power SHAPETM 2010. Foram selecionados pontos nas superfícies linguais dos dentes e traçadas 14 medidas para determinar a forma e a dimensão da arcada dentária. RESULTADOS: o teste de Shapiro-Wilk possibilitou definir uma forma de arcada pequena utilizando o percentil 25% (P25%), uma arcada média (P50%) e uma forma de arcada grande, pelo percentil 75% (P75%). O teste t de Student comparou se houve uma diferença entre os sexos, e foram encontrados 12 tamanhos de arcadas dentárias. CONCLUSÕES: a partir dos resultados obtidos foi possível definir uma forma de arco contínuo para ser utilizado na técnica lingual Straight Wire (LSW): parábola levemente achatada na região anterior. Devido a similaridade entre alguns tamanhos de arcadas dentárias, encontrados pelo dimorfismo sexual, pôde ser elaborado um diagrama de arcadas de maneira mais simplificada. .

Rapid maxillary expansion effects: An alternative assessment method by means of cone-beam tomography

INTRODUCTION: This study aims to develop a method to assess the changes in palatal and lingual cross-sectional areas in patients submitted to rapid maxillary expansion (RME). METHODS: The sample comprised 31 Class I malocclusion individuals submitted to RME and divided into two groups treated with Haas (17 patients) and Hyrax (14 patients) expanders. Cone-beam computed tomography scans were acquired at T0 (before expansion ) and T1 (six months after screw stabilization). Maxillary and mandibular cross-sectional areas were assessed at first permanent molars and first premolars regions and compared at T0 and T1. Mandibular occlusal area was also analyzed. RESULTS: Maxillary cross-sectional areas increased in 56.18 mm2 and 44.32 mm2 for the posterior and anterior regions. These values were smaller for the mandible, representing augmentation of 40.32 mm2 and 39.91 mm2 for posterior and anterior sections. No differences were found when comparing both expanders. Mandibular occlusal area increased 43.99mm2 and mandibular incisors proclined. Increments of 1.74 mm and 1.7 mm occurred in mandibular intermolar and interpremolar distances. These same distances presented increments of 5.5 mm and 5.57 mm for the maxillary arch. CONCLUSION: Occlusal and cross-sectional areas increased significantly after RME. The method described seems to be reliable and precise to assess intraoral area changes. .

INTRODUÇÃO: o presente estudo teve como objetivo desenvolver um método para avaliar as mudanças nas áreas transversais palatinas e linguais em pacientes submetidos à expansão rápida da maxila (ERM). MÉTODOS: a amostra foi composta por 31 indivíduos com má oclusão Classe I de Angle, submetidos a ERM e divididos em dois grupos, tratados com expansores tipo Haas (17 pacientes) e de Hyrax (14 pacientes). Tomografias computadorizadas de feixe cônico foram adquiridas em T0 e T1 (antes da expansão e seis meses após a estabilização do parafuso). Áreas transversais da maxila e mandíbula foram avaliadas nas regiões de primeiros molares permanentes e pré-molares e comparadas entre T0 e T1. A área oclusal mandibular também foi analisada. RESULTADOS: as áreas transversais maxilares aumentaram 56,18mm2 e 44,32mm2 para regiões posterior e anterior, respectivamente. Esses valores foram menores para mandíbula, representando aumentos de 40,32mm2 e de 39,91mm2 para as seções anterior e posterior. Não foram encontradas diferenças quando se comparam os dois expansores. A área oclusal mandibular aumentou 43,99mm2 e incisivos inferiores vestibularizaram. Incrementos de 1,74mm e 1,7mm ocorreram entre as distâncias intermolares e interpré-molares inferiores. Essas mesmas distâncias apresentaram incrementos de 5,5mm e de 5,57mm para maxila. CONCLUSÃO: as áreas transversais avaliadas e oclusal de mandíbula aumentaram significativamente após a ERM. O processo descrito parece ser um método confiável e preciso para avaliar as mudanças das área intrabucais propostas. .

Cortical projection of the inferior choroidal point as a reliable landmark to place the corticectomy and reach the temporal horn through a middle temporal gyrus approach / Projeção cortical do ponto coroideo inferior como uma referência anatômica confiável para a realização da corticectomia e abordagem do corno temporal através do giro temporal médio.

Objective To establish preoperatively the localization of the cortical projection of the inferior choroidal point (ICP) and use it as a reliable landmark when approaching the temporal horn through a middle temporal gyrus access. To review relevant anatomical features regarding selective amigdalohippocampectomy (AH) for treatment of mesial temporal lobe epilepsy (MTLE). Method The cortical projection of the inferior choroidal point was used in more than 300 surgeries by one authors as a reliable landmark to reach the temporal horn. In the laboratory, forty cerebral hemispheres were examined. Conclusion The cortical projection of the ICP is a reliable landmark for reaching the temporal horn. .

Objetivo Estabelecer a projeção cortical do ponto coiroideo inferior e usá-la como referência para realizar a corticectomia e a abordagem do corno temporal do ventrículo lateral em cirurgias para o tratamento da epilepsia temporal mesial. Método A projeção cortical do ponto coroideo inferior foi utilizada por um dos autores seniors em mais de 300 casos de epilepsia temporal mesial para atingir o corno temporal do ventrículo lateral. Conclusão A projeção cortical do ponto coroideo inferior foi útil e confiável na abordagem do corno temporal do ventrículo lateral e ela está geralmente localizada na margem inferior do giro temporal médio, em média, a 4,52 cm posterior ao polo temporal. .

Comparative morphometric study of the sigmoid sinus sulcus and the jugular foramen / Estudo morfométrico comparativo do sulco do seio sigmóideo e do forame jugular

Objective To compare the right and left sides of the same skulls as far as the described landmarks are concerned, and establish the craniometric differences between them. Method We carried out measurements in 50 adult dry human skulls comparing both sides. Results The sigmoid sinus width at the sinodural angle level was larger on the right side in 78% of the cases and at the level of the digastric notch in 72%. The jugular foramen width was also larger on the right side in 84% of the cases. The sigmoid sinus distance at the level of the digastric notch was larger on the right side in 64% of the cases, and the sigmoid sinus distance at the level of the digastric notch to the jugular foramen was larger on the right side in 70% of the cases. Conclusion Significant craniometric differences were found between both sides of the same skulls. .

Objetivo Comparar os lados direito e esquerdo no mesmo crânio nos pontos referenciais descritos e definir as diferenças craniométricas entre ambos. Método Realizamos mensurações em 50 crânios secos de humanos adultos comparando os lados direito e esquerdo. Resultados Como resultado, obtivemos as medidas da largura do seio sigmóideo na altura do ângulo sinodural maiores no lado direito em 78% dos casos e na altura do ponto digástrico em 72%. A largura do forame jugular foi também maior no lado direito em 84% dos casos. A distância do seio sigmóideo na altura do ângulo sinodural até a altura do ponto digástrico foi maior do lado direito em 64% dos casos, e a distância do seio sigmóideo na altura do ponto digástrico até o forame jugular foi maior do lado direito em 70% dos casos. Conclusão Diferenças craniométricas significativas foram encontradas entre os dois lados do crânio. .

Tooth-size discrepancy: A comparison between manual and digital methods

INTRODUCTION: Technological advances in Dentistry have emerged primarily in the area of diagnostic tools. One example is the 3D scanner, which can transform plaster models into three-dimensional digital models. OBJECTIVE: This study aimed to assess the reliability of tooth size-arch length discrepancy analysis measurements performed on three-dimensional digital models, and compare these measurements with those obtained from plaster models. MATERIAL AND METHODS: To this end, plaster models of lower dental arches and their corresponding three-dimensional digital models acquired with a 3Shape R700T scanner were used. All of them had lower permanent dentition. Four different tooth size-arch length discrepancy calculations were performed on each model, two of which by manual methods using calipers and brass wire, and two by digital methods using linear measurements and parabolas. RESULTS: Data were statistically assessed using Friedman test and no statistically significant differences were found between the two methods (P > 0.05), except for values found by the linear digital method which revealed a slight, non-significant statistical difference. CONCLUSIONS: Based on the results, it is reasonable to assert that any of these resources used by orthodontists to clinically assess tooth size-arch length discrepancy can be considered reliable. .

INTRODUÇÃO: na Odontologia, os avanços tecnológicos vêm se manifestando, principalmente, em instrumentos de diagnóstico, como o desenvolvimento dos scanners 3D, capazes de transformar modelos de gesso em modelos digitais tridimensionais. OBJETIVO: o objetivo da presente pesquisa foi avaliar a confiabilidade da análise da Discrepância de Modelo realizada em modelos digitais tridimensionais, comparando-a com a obtida em modelos de gesso. MÉTODOS: utilizou-se modelos de gesso das arcadas dentárias inferiores e seus correspondentes modelos digitais tridimensionais, adquiridos por meio do scanner 3Shape R700T. Foram realizados quatro diferentes cálculos da Discrepância de Modelo para cada modelo selecionado, dois desses por meio de métodos manuais, utilizando paquímetro e fio de latão, e dois por meio de métodos digitais, utilizando medições lineares e por meio da confecção de uma parábola. RESULTADOS: os dados obtidos foram avaliados estatisticamente por meio do teste de Friedman, e observou-se não haver diferença estatisticamente significativa entre os métodos utilizados (p > 0,05), exceto os valores obtidos pelo método digital linear, onde observou-se uma pequena diferença estatística, porém, não são valores considerados clinicamente significativos. CONCLUSÃO: com base nos resultados, é possível afirmar que, quaisquer desses recursos que o ortodontista venha a utilizar em sua vida clínica para obtenção da Discrepância de Modelo, esses são considerados métodos confiáveis. .

Photometric analysis of esthetically pleasant and unpleasant facial profile

Objective: To identify which linear, angular and proportionality measures could influence a profile to be considered esthetically pleasant or unpleasant, and to assess sexual dimorphism. Methods: 150 standardized facial profile photographs of dental students of both sexes were obtained and printed on photographic paper. Ten plastic surgeons, ten orthodontists and ten layperson answered a questionnaire characterizing each profile as pleasant, acceptable or unpleasant. With the use of a score system, the 15 most pleasant and unpleasant profiles of each sex were selected. The photographs were scanned into AutoCAD computer software. Linear, angular and proportion measurements were obtained using the software tools. The average values between groups were compared by the Student's t-test and the Mann-Whitney test at 5%. Results: The linear measures LL-S, LL-H, LL-E, LL-B and Pn-H showed statistically significant differences (p < 0.05). Statistical differences were also found in the angular measures G'.Pn.Pg', G'.Sn.Pg' and Sn.Me'.C and in the proportions G'-Sn:Sn-Me' and Sn-Gn':Gn'-C (p < 0.05). Differences between sexes were found for the linear measure Ala-Pn, angles G'-Pg'.N-Pn, Sn.Me'.C, and proportions Gn'-Sn:Sn-Me' and Ala-Pn:N'-Sn. (p < 0.05). Conclusion: The anteroposterior position of the lower lip, the amount of nose that influences the profile, facial convexity, total vertical proportion and lip-chin proportion appear to influence pleasantness of facial profile. Sexual dimorphism was identified in nasal length, nasofacial and lower third of the face angles, total vertical and nasal height/length proportions. .

Objetivo: identificar quais medidas lineares, angulares e de proporcionalidade influenciam para um perfil ser considerado agradável ou desagradável, e avaliar o dimorfismo sexual. Métodos: foram obtidas e impressas em papel fotográfico 150 fotografias padronizadas do perfil facial de acadêmicos de Odontologia de ambos os sexos. Dez cirurgiões-plásticos, dez ortodontistas e dez leigos responderam um questionário caracterizando cada perfil em agradável, aceitável ou desagradável. Com a utilização de um sistema de escore, foram selecionadas as fotografias dos 15 perfis mais agradáveis e dos 15 mais desagradáveis de cada sexo. As fotografias foram digitalizadas para o programa de computador AutoCAD, e medidas lineares, angulares e de proporcionalidade foram mensuradas utilizando-se ferramentas do programa. As médias obtidas entre os grupos foram comparadas pelos testes t de Student e de Mann-Whitney a 5%. Resultados: as medidas lineares Li-S, Li-H, Li-E, Li-B e Pn-H apresentaram diferenças estatisticamente significativas (p < 0,05). Os ângulos G'.Pn.Pg', G'.Sn.Pg' e Sn.Me'.C e as medidas de proporcionalidade G'-Sn:Sn-Me' e Sn-Gn':Gn'-C também apresentaram diferenças significativas (p < 0,05). Diferenças significativas entre os sexos foram identificadas na medida linear Ala-Pn, nos ângulos G'-Pg'.N'-Pn, Sn.Me'.C e proporções Gn'-Sn:Sn-Me' e Ala-Pn:N'-Sn (p < 0,05). Conclusão: o posicionamento anteroposterior do lábio inferior, a quantidade do nariz que influencia o perfil, a convexidade facial, a proporção vertical total e lábio-queixo parecem influenciar a agradabilidade do perfil facial. Dimorfismo sexual foi identificado na medida linear comprimento nasal, nos ângulos nasofacial e terço inferior da face e nas proporções vertical total e comprimento/altura nasal. .

Micro-endoscopic ear anatomy of guinea pig applied to experimental surgery

PURPOSE: To describe topographic and endoscopic anatomy of guinea pig ear for development of surgical approaches in experimental studies. METHODS: Experimental study. Eight adult guinea pigs (Cavia porcellus) were used in this study. Four animals were described through endoscopic view and four animals were used to describe topographic anatomy. RESULTS: The main structures of middle ear were well identified through endoscopy view: oval and round window, ossicles and vascular structures. Temporal bone position, landmarks and its relations to skull are perceived with topographic description. CONCLUSION: Topographic anatomic description allowed exposition of temporal bone relations for external surgical approaches. Alternatively, grooves and middle ear structures were identified and may be used to transcanal accesses. .

Are Spinal or Paraspinal Anatomic Markers Helpful for Vertebral Numbering and Diagnosing Lumbosacral Transitional Vertebrae?

OBJECTIVE: To evaluate the value of spinal and paraspinal anatomic markers in both the diagnosis of lumbosacral transitional vertebrae (LSTVs) and identification of vertebral levels on lumbar MRI. MATERIALS AND METHODS: Lumbar MRI from 1049 adult patients were studied. By comparing with the whole-spine localizer, the diagnostic errors in numbering vertebral segments on lumbar MRI were evaluated. The morphology of S1-2 disc, L5 and S1 body, and lumbar spinous processes (SPs) were evaluated by using sagittal MRI. The positions of right renal artery (RRA), superior mesenteric artery, aortic bifurcation (AB) and conus medullaris (CM) were described. RESULTS: The diagnostic error for evaluation of vertebral segmentation on lumbar MRI alone was 14.1%. In lumbarization, all patients revealed a well-formed S1-2 disc with squared S1 body. A rhombus-shaped L5 body in sacralization and a rectangular-shaped S1 body in lumbarization were found. The L3 had the longest SP. The most common sites of spinal and paraspinal structures were: RRA at L1 body (53.6%) and L1-2 disc (34.1%), superior mesenteric artery at L1 body (55.1%) and T12-L1 disc (31.6%), and AB at L4 body (71.1%). CM had variable locations, changing from the T12-L1 disc to L2 body. They were located at higher sacralization and lower lumbarization. CONCLUSION: The spinal morphologic features and locations of the spinal and paraspinal structures on lumbar MRI are not completely reliable for the diagnosis of LSTVs and identification on the vertebral levels.

The Efficacy of Carotid Tubercle as an Anatomical Landmark for Identification of Cervical Spinal Level in the Anterior Cervical Surgery: Comparison with Preoperative C-arm Fluoroscopy

BACKGROUND: In cervical anterior approach, transverse skin incision is preferred due to cosmetic reasons. Precise skin incision is required to reach the surgery segment while minimizing soft tissue injury. Skin incision site is frequently identified using C-arm fluoroscopy or the carotid tubercle. Accordingly, this study was conducted to investigate the efficacy of skin incision using the carotid tubercle as a marker. METHODS: This study was retrospectively conducted on 114 patients who underwent anterior cervical surgery by the same surgeon from April 2004 to June 2012. The rate of the appropriate insertion of K-wire, which was inserted into the disc after anterior approach, into the surgery segment was compared between 62 patients where skin incision site was identified using C-arm fluoroscopy before skin incision and 52 patients where skin incision site was identified using carotid tubercle palpitation before surgery. RESULTS: The needle was shown to have been inserted into the planned site in 106 patients out of the total 114 patients. The appropriate insertion of the needle was shown in 59 patients of group I (95.2%) and in 47 patients of group II (90.4%). Although the success rate was higher in group I than group II, it was statistically insignificant. The success rate of one-segment surgery was shown to be 89.7% in group I and 82.6% in group II. Although the success rate was higher in group I than group II, it was statistically insignificant. The success rate of two-segment surgery was shown to be 100% in group I, and 96.4% in group II due to one case of the failure at C3-4 and C5-6. The success rate of three- and four-segment surgeries was shown to be 100% in both groups. CONCLUSIONS: The identification of skin incision site via carotid tubercle palpation was useful for surgeries involving two or more segments. Furthermore, it could be useful for one-segment surgery if surgical site is identified using vertebral body or soft tissues such as longus collis rather than insertion into the disc.

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.