Cephalometric Characteristics in Chilean Latino Population with Normal Occlusion and Harmonic Profiles in Permanent Dentition. A Retrospective Study / Características Cefalométricas en Población Latina Chilena con Oclusión Normal y Perfiles Armónicos en Dentición Permanente. Un Estudio Retrospectivo

SUMMARY: Malocclusion is usually treated based on clinical decisions complemented with a cephalometric analysis, allowing the comparison of an individual with standard reference norms. Cephalometric standards have mostly been obtained from Caucasian population, but may not be appropriate for other ethnic groups, becoming a clinically relevant problem in multicultural and multiracial societies. The present study aimed to establish cephalometric norms for Chilean-Latino population, using a representative sample of class I individuals in permanent dentition. A sample of 72 cephalometric x-rays of class I growing individuals (47 women and 25 men) between 10 and 20 years of age with class I occlusion and harmonic profile was obtained from the records of the Universidad de los Andes taken between 2012 and 2019, including 1164 individuals. The radiographs were classified according to their cervical vertebral maturation status, and cephalometrically analyzed, obtaining vertical and sagittal parameters in soft and hard tissues, which were compared with Caucasian cephalometric norms. The statistical analysis was performed using descriptive and inferential statistics (T-test, ANOVA and Bonferroni tests). Cephalometric norms were obtained for hard and soft tissues. Upon comparison with Caucasian norms, the subjects included in the sample present a tendency towards a convex profile, significant incisal proclination, dental protrusion, labial biprotrusion and an acute nasolabial angle. There are cephalometric differences between the Caucasian cephalometric norms and those observed Chilean Latino population, displaying differences at a hard and soft tissue level that should be taken into account for clinical decision making in Orthodontics.

La maloclusión generalmente se trata con base en decisiones clínicas complementadas con un análisis cefalométrico, lo que permite la comparación de un individuo con normas de referencia estándar. Los estándares cefalométricos se han obtenido en su mayoría de población caucásica, pero pueden no ser apropiados para otros grupos étnicos, convirtiéndose en un problema clínicamente relevante en sociedades multiculturales y multirraciales. El presente estudio tuvo como objetivo establecer normas cefalométricas para población chileno-latina, utilizando una muestra representativa de individuos clase I en dentición permanente. Se obtuvo una muestra de 72 radiografías cefalométricas de individuos en crecimiento clase I (47 mujeres y 25 hombres) entre 10 y 20 años de edad con oclusión clase I y perfil armónico de los registros de la Universidad de los Andes tomados entre 2012 y 2019, incluidas 1164 personas. Las radiografías se clasificaron según su estado de maduración vertebral cervical, y se analizaron cefalométricamente, obteniendo parámetros verticales y sagitales en tejidos blandos y duros, que se compararon con normas cefalométricas caucásicas. El análisis estadístico se realizó mediante estadística descriptiva e inferencial (T-test, ANOVA y pruebas de Bonferroni). Se obtuvieron normas cefalométricas para tejidos duros y blandos. En comparación con las normas caucásicas, los sujetos incluidos en la muestra presentan una tendencia hacia un perfil convexo, proinclinación incisal significativa, protrusión dental, biprotrusión labial y un ángulo nasolabial agudo. Existen diferencias entre las normas cefalométricas caucásicas y las observadas en población latina chilena, mostrando diferencias a nivel de tejidos duros y blandos que se deben considerar para la toma de decisiones clínicas en Ortodoncia.

Concordance of the vestibular bone thickness at the level of point a between teleradiography and cone beam computed tomography / Concordancia del espesor óseo vestibular a nivel del punto a entre telerradiografía y tomografía computarizada de haz cónico

Objective: The aim of this study was to determine the concordance of the vestibular bone thickness measured at the level of point A between Teleradiography and Cone Beam Computed Tomography (CBCT). Materials and Methods: This study consisted of a cross-sectional analytical design of concordance that evaluated the teleradiographies and CBCTs of 32 patients. The measurements were performed by three evaluators, specialists in orthodontics. Two of them measured the CBCTs and one evaluated the teleradiographs. The concordance of both tests was determined using the Concordance Correlation Coefficient. Results: When evaluating the value of the vestibular bone thickness at the level of point A between the CBCT and the teleradiography, it was observed that the mean value of the absolute difference between the two was 0.95±0.74, 95%CI [0.68­1.22], being statistically significant (p=0.0027). When the concordance between both tests was analyzed, it was observed that it was poor (CCC=0.204 95%CI [0.014­0.394]), although statistically significant (p<0.00001). Conclusions: It was possible to conclude that there is no concordance in the measurement of the vestibular bone thickness at the level of Point A between the Teleradiography and the CBCT.

Objetivo: El objetivo de este estudio fue determinar la concordancia del espesor óseo vestibular medido a nivel del punto A entre la Telerradiografía y la Tomografía computarizada de haz cónico (CBCT). Materiales y Métodos: Esta investigación presentó un diseño analítico transversal de concordancia en el que se evaluaron las telerradiografías y CBCT de 32 pacientes. Las mediciones fueron realizadas por tres evaluadores especialistas en ortodoncia, dos de ellos midieron los CBCT y uno las telerradiografías. La concordancia de ambos exámenes fue medida mediante Coeficiente de Correlación de Concordancia. Resultados: Al evaluar el valor del grosor óseo vestibular a nivel del punto A entre el CBCT y la telerradiografía, se observó que el valor promedio de diferencia absoluta entre ambos fue de 0,95±0,74 IC95% [0,68­1,22], siendo estadísticamente significativas (p=0,0027). Cuando se analizó la concordancia entre ambos exámenes se observó que esta fue pobre (CCC=0,204 IC95 % [0,014­0,394]), aunque estadísticamente significativa (p<0,00001). Conclusión: Se pudo concluir que no existe concordancia en la medición del espesor óseo vestibular medido a nivel del Punto A entre la Telerradiografía y el CBCT.

Relationship between the occlusal plane and three different levels of ala-tragus line in a sample of sudanese adults / Relación entre el plano oclusal y tres niveles diferentes de la línea ala-trago en una muestra de adultos sudaneses

Aim: Correct orientation of the occlusal plane plays a vital role in achieving the perfect occlusal balance and function of complete dentures. This study aimed to evaluate the most reliable posterior reference point of the ala-tragus line (ATL) concerning occlusal plane (OP) in a sample of the dentate Sudanese population. Materials and Methods: A total of 150 subjects with healthy and well-aligned permanent teeth were randomly selected. Right lateral profile photographs were taken with subjects having a fox plane placed intra-orally, contacting the occlusal plane. Reference points corresponding to inferior, middle, and superior borders of the tragus and inferior border of the ala of the nose were marked on photographs. The angles between the lines were measured using the Auto-CAD software program, and the most parallel relationship was determined. Descriptive statistics in terms of means and standard deviations were presented. Independent t-test and one-way ANOVA tests were used to compare as appropriate. A p-value < 0.05 was considered significant. Results: The mean angle formed by the OP and ATL was 8.5±3.69º for the superior level, 4.68±3.13º for the middle line, and 2.89±2.57º for the inferior line. A significant difference was found between the means of the three angles (p< 0.001), while no significant difference (p> 0.05) was found between both genders regarding the measured angles. Conclusions: The line joining the inferior border of the ala of the nose with the inferior border of the tragus of the ear was the most reliable line in terms of parallelism to determine the occlusal plane orientation.

Antecedentes: La orientación correcta del plano oclusal juega un papel vital para lograr el equilibrio oclusal perfecto y la función de las prótesis completas. Este estudio tuvo como objetivo evaluar el punto de referencia posterior más confiable de la línea ala-trago (ATL) con respecto al plano oclusal (OP) en una muestra de la población dentada de Sudán. Materiales y Métodos: Se seleccionaron aleatoriamente un total de 150 sujetos con dientes permanentes sanos y bien alineados. Se tomaron fotografías de perfil lateral derecho de sujetos a los que se les colocó un plano de zorro intraoralmente, en contacto con el plano oclusal. En las fotografías se marcaron los puntos de referencia correspondientes a los bordes inferior, medio y superior del trago y al borde inferior del ala de la nariz. Los ángulos entre las líneas se midieron utilizando el programa de software Auto-CAD y se determinó la relación más paralela. Se presentaron estadísticas descriptivas en términos de medias y desviaciones estándar. Se utilizaron prueba-t independiente y prueba ANOVA unidireccional para las comparaciones, según correspondiera. Se consideró significativo un valor de p<0,05. Resultados: El ángulo medio formado por OP y ATL fue de 8,5±3,69º para el nivel superior, 4,68±3,13º para la línea media y 2,89±2,57º para la línea inferior. Se encontró una diferencia significativa entre las medias de los tres ángulos (p< 0,001), mientras que no se encontró diferencia significativa (p>0,05) entre ambos sexos con respecto a los ángulos medidos. Conclusión: La línea que une el borde inferior del ala de la nariz con el borde inferior del trago de la oreja fue la línea más confiable en términos de paralelismo para determinar la orientación del plano oclusal.

Caracterización epidemiológica, clínica y cefalométrica del brote anormal de los terceros molares / Epidemiological, clinical and cephalometric characterization of the abnormal eruption of third molars

Introducción: El brote de los terceros molares es un proceso que no está del todo explicado, pero durante su erupción puede provocar diferentes accidentes o complicaciones. Objetivo: Caracterizar el brote anormal de los terceros molares según variables epidemiológicas, clínicas y cefalométricas. Método: Se realizó un estudio observacional, descriptivo y transversal en la Clínica Estomatológica Provincial Docente «Mártires del Moncada», de Santiago de Cuba, desde noviembre de 2019 a febrero de 2020. La población estuvo conformada por jóvenes de 18 a 25 años de edad; la muestra fue seleccionada por muestreo aleatorio simple. Se tuvieron en cuenta las siguientes variables: sexo, color de la piel, brote anormal y otras variables cefalométricas. Resultados: De los 84 dientes incluidos en el estudio, se detectaron 66 terceros molares con brote anormal (78,6 %). El promedio asociado al brote de estos molares de espacio óseo superior insuficiente fue igual para los superiores con medias de 25,9 mm; el de angulación inadecuada resultó obtuso en el superior izquierdo con 128,3º y agudo en los inferiores derechos con 58,8º; asimismo el mayor diámetro mesiodistal inadecuado fue el de los inferiores derechos con 15,7 mm. Conclusiones: El brote anormal de los terceros molares se caracteriza por afectar, de forma importante, a féminas y a individuos mestizos. Su observación se singulariza, fundamentalmente, en molares inferiores con espacios óseos posteriores reducidos, mesioangulaciones y diámetros mesiodistales considerables.

Introduction: eruption of the third molars is a process that is not fully explained in the literature; however it is known that their eruption can cause different complications. Objective: to characterize the abnormal eruption of third molars according to epidemiological, clinical and cephalometric variables. Methods: an observational, descriptive and cross-sectional study was carried out at "Mártires del Moncada" Provincial Teaching Dental Clinic, in Santiago de Cuba, from November 2019 to February 2020. The population consisted of young people aged 18-25 years; the sample was selected by simple random sampling. Gender, skin color, abnormal eruption and other cephalometric variables were taken into account. Results: sixty-six third molars with abnormal eruption were detected from the 84 teeth included in the study (78.6%). The average associated with the eruption of these molars with insufficient upper bone space was the same for the upper ones with means of 25.9 mm; the average with inadequate angulation was obtuse in the upper left third molar with 128.3º and the acute one in the lower right third molars with 58.8º; the lower right third molars likewise had the largest inadequate mesiodistal diameter with 15.7 mm. Conclusions: the abnormal eruption of third molars is characterized by significantly affecting females and mixed-race individuals. Its observation is singled out, fundamentally, in lower molars with reduced posterior bone spaces, mesioangulations and considerable mesiodistal diameters.

Volumetric Evaluation of the Upper Airways in Relation to the Gonial Angle / Avaliação Volumétrica das Vias Aéreas Superiores com Relação ao Ângulo Goníaco

The upper airspace is essential to understand the physiology and pathogenesis of its obstruction, complementary exams based on images have been used to evaluate the upper airspace. The objective of this study was to evaluate, by means of computed tomography, the upper airways (UAS), in relation to anatomical variables, emphasizing the gonial angle and comparing it with volume in mm³, sex and age. A total of 124 computed tomography scans were analyzed using DICOM files (digital image communication in medicine) made available by a radiology clinic using the ITK-snap program (version 3.6.0), upper airway volumes, sex, age and gonial angle values on both the right and left sides were tabulated in a table in the Excel 2010 program of the Microsoft Office 2010 package, and subsequently analyzed in the SPSS software with statistical analysis using the Levene Test and also the ANOVA test, to obtain of the results. The values found for the gonial angle did not indicate a significant difference. However, the present work confirms that within each of these groups there is a homogeneity of variances, corroborating the results reported in the literature. However, regarding the volume of the upper airways, we found that in men and in individuals aged over 34 years, the volume is greater.(AU)

O espaço aéreo superior é essencial para compreender a fisiologia e a patogênese de sua obstrução, exames complementares baseados em imagens têm sido empregados para avaliar o espaço aéreo superior. O objetivo desse estudo foi avaliar por meio de tomografia computadorizada, as vias aéreas superiores (VAS), com relação a variáveis anatômicas, dando ênfase ao ângulo goníaco e comparando com volume em mm³, sexo e idade. Foram analisados 124 exames de tomográfica computadorizada, por meio dos arquivos DICOM (comunicação de imagens digitais em medicina) disponibilizados por uma clínica radiológica, através do programa ITK-snap (versão 3.6.0), os volumes das vias aéreas superiores, o sexo, a idade e os valores do ângulo goníaco tanto do lado direito como do lado esquerdo foram tabulados em tabela no programa Excel 2010 do pacote Microsoft Office 2010, e analisados posteriormente no software SPSS com análise estatística pelo Teste de Levene e também teste ANOVA, para obtenção dos resultados. Os valores encontrados para o ângulo goníaco não indicaram diferença significativa. Contudo, o presente trabalho confirma que dentro de cada um desses grupos há uma homogeneidade das variâncias e corroborando com os resultados relatados na literatura. No entanto com relação ao volume das vias aéreas superiores encontramos que em homens e em indivíduos com idade superior a 34 anos o volume é superior.(AU)

Reproducibility of linear and angular cephalometric measurements obtained by an artificial-intelligence assisted software (WebCeph) in comparison with digital software (AutoCEPH) and manual tracing method

ABSTRACT Introduction: It has been suggested that human errors during manual tracing of linear/angular cephalometric parameters can be eliminated by using computer-aided analysis. The landmarks, however, are located manually and the computer system completes the analysis. With the advent of Artificial Intelligence in the field of Dentistry, automatic location of the landmarks has become a promising tool in digital Orthodontics. Methods: Fifty pretreatment lateral cephalograms obtained from the Orthodontic department of SRM dental college (India) were used. Analysis were done by the same investigator using the following methods: WebCeph™, AutoCEPH© for Windows or manual tracing. Landmark identification was carried out automatically by Artificial Intelligence in WebCeph™ and with a mouse driven cursor in AutoCEPH©, and manually using acetate sheet and 0.3-mm pencil, ruler and a protractor. The mean differences of the cephalometric parameters obtained between the three methods were calculated using ANOVA with statistical significance set at p<0.05. Intraclass correlation coefficient (ICC) was used to determine both reproducibility and agreement between linear and angular measurements obtained from the three methods and intrarater reliability of repeated measurements. ICC value of >0.75 indicated good agreement. Results: Intraclass correlation coefficient between the three groups was >0.830, showing good level of agreement, and the value within each group was >0.950, indicating high intrarater reliability. Conclusion: Artificial Intelligence assisted software showed good agreement with AutoCEPH© and manual tracing for all the cephalometric measurements.

RESUMO Introdução: Tem sido sugerido que os erros humanos durante o traçado manual das medidas cefalométricas lineares/angulares podem ser eliminados usando a análise guiada por computador. Os pontos de referência, no entanto, são localizados manualmente e o sistema computadorizado completa a análise. Com o advento da Inteligência Artificial na Odontologia, a localização automática dos pontos de referência tornou-se uma ferramenta promissora na Ortodontia digital. Métodos: Cinquenta cefalogramas laterais pré-tratamento obtidos do departamento de Ortodontia da Faculdade de Odontologia SRM (Índia) foram usados. Todas as análises foram feitas pelo mesmo investigador, usando os seguintes métodos: WebCeph™, AutoCEPH© para Windows ou traçado manual. A identificação dos pontos foi realizada automaticamente por Inteligência Artificial no WebCeph™; com o cursor do mouse, no AutoCEPH©; e manualmente, utilizando folha de acetato e lápis 0,3 mm, régua e transferidor. As diferenças médias dos parâmetros cefalométricos entre os três métodos foram calculadas por ANOVA com significância estatística fixada em p<0,05. O coeficiente de correlação intraclasse (ICC) foi usado para determinar a reprodutibilidade e a concordância entre as medidas lineares e angulares obtidas pelos três métodos e a confiabilidade intraexaminador para medidas repetidas. O valor de ICC > 0,75 indicou boa concordância. Resultados: O ICC entre os três grupos foi >0,830, mostrando bom nível de concordância, e o valor dentro de cada grupo foi >0,950, indicando alta confiabilidade intra-avaliador. Conclusão: O software assistido por Inteligência Artificial mostrou boa concordância com o AutoCEPH© e o traçado manual para todas as medidas cefalométricas.

Breastfeeding practices and head circumference in young children: a systematic review

ABSTRACT OBJECTIVE To review observational studies on the association between breastfeeding (BF) practices and head circumference (HC) of children < 2 years old. METHODS A systematic review was conducted using the following electronic databases of health sciences: PubMed, Latin American and Caribbean Literature in Health Sciences (Lilacs), Web of Science and Scopus. We selected observational studies published in any language from January 01, 2010 to November 19, 2021, from different populations that investigated the association between BF practice and HC among healthy children < 2 years old. Titles and abstracts were screened independently by two evaluators. RESULTS From the 4,229 articles identified, 24 were included in this review: 6 cross-sectional, 17 longitudinal, and 1 case-control. The studies varied in their definition of the variables for BF and in reporting its practice, frequency, duration, and feeding method. Regarding HC, the authors analyzed the mean differences, abnormal values (z-score above + 2SD or below -2SD according to the World Health Organization (WHO) growth standards, 2007), and longitudinal growth parameters. The findings of this review suggest that BF may have a positive relationship with HC at the beginning of life. CONCLUSIONS Our findings suggest that BF, especially exclusive BF, may play a protective role against abnormal HC values in young children. However, more robust evidence with standardized BF indicators and WHO growth standards (2007) are required.

Incidence of different morphological types of sella turcica: Cephalometric study

Introduction: Sella turcica (ST) is a saddle-shaped structure located on the intracranial surface of the sphenoid bone in the middle cranial fossa. The sella turcica serves as an important anatomical reference in orthodontics partly because the s-point, placed centrally in the sella region, is a central fix point in cephalometric analysis and partly because the contour of the anterior wall is used in evaluation of craniofacial growth. Morphologically, three basic types - oval, round, and flat - have been classified, the oval and round types being the most common. Aim and objectives: To describe the predominant morphological shape of sella turcica. Materials and methods: Prospective clinical study which was conducted in the Postgraduate Department of Oral Medicine and Radiology of Government Dental College and Hospital Srinagar. This prospective study included total of digital lateral cephalometric radiographs of 180 patients (90 males and 90 females) between 12-65 years of age, Digital lateral cephalometric radiographs were taken by using CARESTREAM SC8100 machine Results: Morphology of sella turcica was found to be typical in just 33.9% of cases. Within the atypical sellae most had oblique anterior wall (27.2%), followed by double contour of the floor (15%), pyramidal shape (14.4%), irregular dorsum sella (6.7%) and bridging (2.8%). Conclusion: Morphological types of sella turcica in this study can be used as reference for additional investigators such as radiologists, orthodontists, maxillofacial surgeons, and neurosurgeons to interpret and plan surgical procedures involving the sellar region

Mandibular angle morphology in open bite subjects according to the skeletal relationship: a cbct short report / Morfología del ángulo mandibular en sujetos con mordida abierta de acuerdo a la relación esquelética: un informe breve en cbct

Aim: The purpose of this research was to three-dimensionally evaluate the mandibular angle morphology in open bite subjects with different sagittal skeletal relationships. Material and Methods: Cone beam computed tomography (CBCT) images of 26 subjects (12 men and 14 women) with anterior open bite were evaluated. The sample included 3 groups categorized by their sagittal skeletal relationship (based on ANB angle and anteroposterior dysplasia indicator (APDI)): Class I (n=9), Class II (n=6) and Class III (n=11). The total gonial angle, upper gonial angle, lower gonial angle, intergonial width, interantegonial width and antegonial notch depth were measured. ANOVA and Tukey tests were used for intergroup comparison. The Kruskal Wallis test was also used when necessary. In addition, the Pearson correlation coefficient was calculated to evaluate significant correlations between overbite and antegonial notch depth with gonial angle, Frankfurt mandibular plane angle (FMA) and the palatal plane-mandibular plane (PP-MP). Results: A significant difference was only found on the upper gonial angle between Class II and Class III (p=0.047). The upper gonial angle showed greater values (48°±3°) with the mandibular branch toward backward in Class III subjects and lower values (42.42°±4.39°) with the mandibular ramus leaning forward in subjects with Class II skeletal relationship. Besides, only a statistically significant correlation was found between overbite and the lower gonial angle (r=-0.418, p=0.034). Conclusion: Mandibular angle morphology is similar in anterior open bite subjects with different sagittal skeletal relationships, except for the upper gonial angle which is increased in Class III and decreased in Class II subjects with open bite. Lower gonial angle is negatively correlated with overbite. This difference should be considered by orthodontists when planning their treatments.

Objetivo: El propósito de esta investigación fue evaluar tridimensionalmente la morfología del ángulo mandibular en sujetos de mordida abierta con diferentes relaciones esqueléticas sagitales. Material y Métodos: Se evaluaron imágenes de tomografía computarizada de haz cónico (CBCT) de 26 sujetos (12 hombres y 14 mujeres) con mordida abierta anterior. La muestra incluyó 3 grupos categorizados por su relación esquelética sagital (según el ángulo ANB y el indicador de displasia anteroposterior (APDI)): Clase I (n=9), Clase II (n=6) y Clase III (n=11). Se midieron el ángulo goniaco total, el ángulo goniaco superior, el ángulo goniaco inferior, el ancho intergonial, el ancho interantegonial y la profundidad de la entalladura antegonial. Se utilizaron las pruebas ANOVA y Tukey para la comparación intergrupal. La prueba de Kruskal Wallis también se utilizó cuando fue necesario. Además, se calculó el coeficiente de correlación de Pearson para evaluar correlaciones significativas entre la sobremordida y la profundidad de la entalladura antegonial con el ángulo goniaco, el ángulo del plano mandibular de Frankfurt (FMA) y el plano palatino-plano mandibular (PP-MP). Resultados: Solo se encontró una diferencia significativa en el ángulo goniaco superior entre la Clase II y la Clase III (p=0.047). El ángulo gonial superior mostró valores mayores (48°±3°) con la rama mandibular hacia atrás en sujetos Clase III y valores más bajos (42,42°±4,39°) con la rama mandibular inclinada hacia adelante en sujetos con Clase II esquelética relación. Además, solo se encontró una correlación estadísticamente significativa entre la sobremordida y el ángulo goniaco inferior (r= -0,418, p= 0,034). Conclusión: La morfología del ángulo mandibular es similar en sujetos con mordida abierta anterior con diferentes relaciones esqueléticas sagitales, excepto por el ángulo goniaco superior que aumenta en la Clase III y disminuye en sujetos de Clase II con mordida abierta. El ángulo gonial inferior se correlaciona negativamente con la sobremordida. Los ortodoncistas deben considerar esta diferencia al planificar sus tratamientos.

Association between the intensity of obstructive sleep apnea and skeletal alterations in the face and hyoid bone / Relação entre a influência da gravidade da apneia obstrutiva do sono e alterações craniofaciais e do posicionamento do osso hioide

Abstract Introduction The association between the intensity of obstructive sleep apnea and skeletal alterations in the face and hyoid bone is still scarcely addressed in the literature. Objective To evaluate whether the intensity of obstructive sleep apnea is associated with craniofacial alterations and the position of the hyoid bone in children with mixed dentition. Methods 76 children aged 7 to 10 years old were examined by otorhinolaryngological evaluation, polysomnography, and orthodontic assessment, including cephalometry. The participants were divided in 3 groups: primary snoring, mild obstructive sleep apnea and moderate to severe obstructive sleep apnea. Cephalometric measures of the face and hyoid bone were assessed. These measures were compared among the different groups by unpaired Student's t test. Moreover, these measures were correlated with the patient's obstructive apnea and hypopnea index variable using Pearson's correlation test. Results Of the 76 children, 14 belonged to group 1, with primary snoring; 46 to group 2, with mild obstructive sleep apnea; and 16 to group 3, with moderate-severe obstructive sleep apnea. There was no difference between the groups regarding the craniofacial variables. Children with obstructive sleep apnea showed a longer distance from the hyoid bone to the mandibular plane when compared to the primary snoring group (p < 0.05). Between the two obstructive sleep apnea subgroups, patients with moderate or severe disease showed significantly shorter horizontal distance between the hyoid bone and the posterior pharyngeal wall (p < 0.05), when compared to the groups with mild obstructive sleep apnea. We also observed a significant positive correlation between obstructive apnea and hypopnea index and the distance from the hyoid to the mandibular plane (p < 0.05) as well as a significant negative association between obstructive apnea and hypopnea index and the horizontal distance from the hyoid to the posterior pharyngeal wall (p < 0.01). Conclusion We did not observe any association between obstructive sleep apnea and linear lateral alterations of the face. In contrast, there is a direct association between obstructive sleep apnea severity and the inferior and posterior position of the hyoid bone in children aged 7 to 10 years old.

Resumo Introdução A relação entre a intensidade da apneia obstrutiva do sono e alterações esqueléticas da face e do hioide em crianças é pouco explorada na literatura. Objetivo Avaliar se a intensidade da apneia obstrutiva do sono correlaciona-se às alterações craniofaciais e ao posicionamento do osso hioide em crianças em fase de dentição mista. Método Foram submetidas 76 crianças entre 7 e 10 anos à avaliação otorrinolaringológica, polissonografia e avaliação ortodôntica, inclusive cefalometria. Os participantes foram divididos em 3 grupos: grupo 1 com ronco primário, grupo 2 com apneia obstrutiva do sono leve e grupo 3 com apneia obstrutiva do sono moderada/grave. Foram analisadas medidas cefalométricas da face e do osso hioide. Essas medidas foram comparadas entre si dentro dos diferentes grupos por teste t de Student não pareado. Além disso, essas medidas foram correlacionadas com a variável índice de apneias obstrutivas e hipopneias do paciente através do teste de correlação de Pearson. Resultados Das 76 crianças, 14 constituíram o grupo 1, ronco primário; 46 o grupo 2, apneia obstrutiva do sono leve; e 16 o grupo 3, apneia obstrutiva do sono moderada/grave. Não se observou diferença significante entre os grupos para as variáveis craniofaciais. Observou-se maior distância do osso hioide ao plano mandibular nos dois grupos com apneia obstrutiva do sono quando comparado ao ronco primário (p < 0,05). Entre os dois subgrupos da apneia obstrutiva do sono, os pacientes com doença moderada ou grave apresentaram distância horizontal entre o hioide e a parede posterior da faringe significantemente menor (p < 0,05), quando comparados aos grupos com apneia obstrutiva do sono leve. Observamos ainda correlação significantemente positiva entre índice de apneias obstrutivas e hipopneias e a distância do hioide ao plano mandibular (p < 0,05) e significantemente negativa entre índice de apneias obstrutivas e hipopneias e distância horizontal do hioide com a parede posterior da faringe (p < 0,01). Conclusão Não observamos relação da apneia obstrutiva do sono com alterações lineares laterais da face. Em contraste, existe relação direta entre a gravidade da apneia obstrutiva do sono e a posição inferior e posterior do osso hioide em crianças entre 7 e 10 anos.

Avaliação do crescimento fetal de crianças por meio da razão peso/perímetro cefálico / Weight/head circumference ratio at birth for assessing fetal growth

Resumo O objetivo deste artigo é utilizar a razão peso/perímetro cefálico ao nascimento para avaliar o crescimento fetal. Estudo transversal aninhado a uma coorte de nascimentos do estado da Paraíba, Nordeste do Brasil, com 726 crianças nascidas a termo e com peso maior ou igual a 2.500 gramas. As medidas antropométricas da criança, características sociodemográficas, cuidados na gestação e tipo de parto foram coletados nas primeiras 24 horas pós-parto. As crianças foram classificadas em proporcionais (peso/perímetro cefálico ≥ 0,87) e desproporcionais (peso/perímetro cefálico < 0,87). Recém-nascidos de menor idade gestacional, com peso ao nascer inferior, do sexo feminino, de famílias não beneficiárias do Programa Bolsa Família, de mães não suplementadas com ácido fólico durante a gravidez e nascidos por cesariana apresentaram menores médias da razão peso/perímetro cefálico. As médias de peso, comprimento e perímetro cefálico foram menores entre as crianças classificadas com desproporção peso/perímetro cefálico, ajustadas pelo sexo da criança. A razão peso/perímetro cefálico é um indicador útil na avaliação do crescimento fetal.

Abstract The scope of this article was to use the weight/head circumference ratio at birth to assess fetal growth. A cross-sectional study was conducted in a birth cohort in the State of Paraíba, Northeast of Brazil, with 726 children born at term and weighing 2,500 grams or more. The anthropometric measurements, sociodemographic characteristics, gestational care and type of delivery were collected in the first 24 hours after birth of infants were assessed. Infants were classified as proportionate (weight/head circumference ratio ≥0.87) versus disproportionate (<0.87). Lower mean weight/head circumference ratio was identified in newborns of lower gestational age, with lower birth weight, female, from families not benefiting from the Bolsa Família Program, of mothers who did not take folic acid during pregnancy and were born by cesarean section. Mean weight, length, and head circumference were lower among infants with disproportionate weight/head circumference ratio, independently of sex. Weight/head circumference ratio is an important indicator of fetal growth.

Cambios en incisivos y su relación con el punto A y el ángulo nasolabial en pacientes Clase II división 2 tratados con y sin extracciones en el Centro Dental Docente UPCH / Changes in incisors and their relationship with point A and nasolabial angle in Class II division 2 patients treated with and without extractions at the UPCH Teaching Dental Center

RESUMEN Antecedentes : Diversos estudios describen las características de la maloclusión clase II-2, sin embargo, son escasos los estudios que evalúan las repercusiones del tratamiento sobre tejidos blandos y esqueléticos. Objetivo : Evaluar los cambios post tratamiento en inclinación y posición incisiva y su relación con el ángulo nasolabial (ANL) y el punto A (PA) en pacientes Clase II división 2, con y sin extracciones en casos de la especialidad de Ortodoncia de la Universidad Peruana Cayetano Heredia. Material y métodos: se realizaron trazados manuales y mediciones de 62 radiografías cefalométricas laterales (31 pre y 31 post-tratamiento), de pacientes con maloclusión de Clase II división 2. El análisis estadístico se realizó con SPSS 21.0 para Windows. Resultados : Se observan proinclinación y protrusión incisiva en todos los pacientes. En pacientes con exodoncias el ANL presentó cambios no significativos, pero correlaciones significativas: cuando aumentó la inclinación incisiva inferior disminuyó el ANL; cuando aumentó el ANL, aumentó el ángulo interincisal (AII). El punto A (PA) experimentó cambios y correlaciones, pero no significativas. En pacientes sin exodoncias no se encontraron correlaciones ni cambios significativos en PA ni en ANL. Las mujeres tratadas sin exodoncia no presentaron cambios significativos, en los hombres los cambios más significativos fueron la inclinación y protrusión incisiva inferior. En los casos con exodoncias en hombres fue el AII; y en las mujeres el AII y el ángulo incisivo superior/ plano palatino. Conclusiones: Existe una relación entre los cambios que se producen en los incisivos y el ANL y PA, aunque la mayoría no son estadísticamente significativos.

ABSTRACT Background : There are studies evaluating cephalometric parameters in Class II division 2 patients. There are no similar investigations in Peru. Objective : To evaluate post-treatment changes in incisor inclination and position and their relationship with the nasolabial angle (ANL) and point A (PA) in Class II division 2 patients, with and without extractions in cases of the Orthodontic specialty program of the Universidad Peruana Cayetano Heredia. Material and methods : manual tracing and measurements of 62 lateral cephalometric radiographs (31 pre and 31 post-treatment) were performed, of patients with Malocclusion Class II division 2. Statistical analysis was performed with SPSS 21.0 for Windows. Results : There was proinclination and incisive protrusion in all patients. In patients with extractions, the ANL presented non-significant changes, but significant correlations: when the lower incisor inclination increased, the ANL decreased; when ANL increased, the interincisal angle (AII) increased. Point A (PA) experienced changes and correlations, but not significant. In patients without extractions, no correlations or significant changes were found in BP or ANL. Women treated without extraction did not show significant changes, in men the most significant changes were lower incisor inclination and protrusion. In the cases with extractions in men it was AII; and in women the AII and the upper incisor angle / palatal plane. Conclusions: There is a relationship between the changes that occur in the incisors and the ANL and PA, although most are not statistically significant.

Oral and cephalometric characteristics of hypohidrotic ectodermal dysplasia: Case report / Características orales y cefalométricas de la displasia ectodérmica hipohidrótica: Reporte de caso

ABSTRACT Hypohydrotic ectodermal dysplasia (HED) is a genetic disorder that affects the development of ectodermal tissues. This study reports a case of a 5-year-old male patient, with clinical extra and intraoral characteristics of HED. The intraoral clinical examination revealed a generalized absence of teeth, panoramic radiograph revealed the presence of permanent first molars with taurodontism, and confirm the oligodontia. Cephalometric analysis revealed a class III skeletal relationship, due to deficiency in the sagittal development of the maxilla and an anti-clockwise growth tendency. Alterations in craniofacial development require multidisciplinary treatment and long-term follow-up to monitor craniofacial growth.

RESUMEN La displasia ectodérmica hipohidrótica (DEH) es un trastorno genético que afecta el desarrollo de los tejidos ectodérmicos. Se realiza el reporte de caso de un paciente masculino de 5 años, con características clínicas extra e intraorales de DEH. El examen clínico intraoral reveló una ausencia generalizada de dientes, la radiografía panorámica reveló la presencia de primeros molares permanentes con taurodontismo y confirmó la oligodoncia. El análisis cefalométrico reveló una relación esquelética de clase III, debido a la deficiencia en el desarrollo sagital del maxilar y una tendencia de crecimiento en sentido antihorario. Las alteraciones en el desarrollo craneofacial requieren un tratamiento multidisciplinario y un seguimiento a largo plazo para controlar el crecimiento craneofacial.

Estudio dimensional de los puntos craneométricos mediosagitales en cráneos de población chilena / Dimensional study of midsagital craneometric points in skulls of Chilean population

RESUMEN: La utilidad de los puntos craneométricos en neurocirugía radica en la estudiada relación que poseen con las estructuras encefálicas y vasculares que subyacen, siendo relevantes al momento de planificar y realizar diversos abordajes y disminuir la morbilidad asociada. A pesar de esto, hasta el momento no se disponen de datos publicados de las distancias de estos puntos craneométricos en población chilena. Se utilizaron 45 cráneos secos de cadáveres adultos. Se realizaron mediciones de las distancias superficiales entre diversos puntos craneométricos mediosagitales. La distancia superficial promedio entre nasion y bregma fue de 12,71 cm; entre bregma y lambda, 12,34 cm; entre lambda e inion, 6,64 cm; entre inion y opistocranio, 5,16 cm; entre lambda y opistocráneo, 3,88 cm y entre inion y opistion, 5,16 cm. Se encontraron diferencias estadísticamente significativas (p<0,05) entre el grupo estudiado con datos obtenidos de la literatura en las distancias nasion-bregma, bregma-lambda, lambda-opistocranio. Las distancias entre los distintos puntos craneométricos en cráneos de población chilena fueron caracterizadas en el presente estudio existiendo algunas diferencias con los datos de la literatura que deben ser considerados en el contexto de la práctica quirúrgica relacionada.

Decline in head circumference growth and associated factors in congenital Zika syndrome / Declínio no crescimento do perímetro cefálico e fatores associados à síndrome congênita associada à infecção pelo vírus Zika / Disminución del crecimiento del perímetro cefálico y factores asociados en el síndrome congénito del Zika

Little is known about the evolution of head circumference (HC) in children with congenital Zika syndrome (CZS). This study aims to evaluate HC growth in children with CZS in the first three years of life and identify associated factors. HC data obtained at birth and in neuropediatric consultations from 74 children with CZS were collected from the Child's Health Handbook, parents' reports, and medical records. Predictors of HC z-score were investigated using different mixed-effects models; Akaike's information criterion was used for model selection. The HC z-score decreased from -2.7 ± 1.6 at birth to -5.5 ± 2.2 at 3 months of age, remaining relatively stable thereafter. In the selected adjusted model, the presence of severe brain parenchymal atrophy and maternal symptoms of infection in the first trimester of pregnancy were associated with a more pronounced reduction in the HC z-score in the first three years of life. The decrease of HC z-score in CZS children over the first three months demonstrated a reduced potential for growth and development of the central nervous system of these children. The prognosis of head growth in the first 3 years of life is worse when maternal infection occurs in the first gestational trimester and in children who have severe brain parenchymal atrophy.

Pouco se sabe sobre a evolução do perímetro cefálico (PC) em crianças com síndrome congênita associada à infecção pelo vírus Zika (SCZ) em acompanhamentos contínuos. Este estudo buscou avaliar o crescimento do PC em crianças com SCZ nos primeiros três anos de suas vidas e identificar os fatores associados a ele. Os dados do PC ao nascimento e obtidos em consultas neuropediátricas de 74 crianças com SCZ foram coletados no Cartão da Criança, nos laudos paternos e em seus prontuários. Os preditores de escore-z para PC foram investigados utilizando-se diferentes modelos de efeitos mistos. O critério de informação de Akaike foi utilizado para selecionar os modelos usados. O escore-z de PC diminuiu de -2,7 ± 1,6 ao nascimento para -5,5 ± 2,2 aos 3 meses de idade, mas permaneceu relativamente estável desde então. No modelo ajustado selecionado, a presença de atrofia parênquimal cerebral grave e sintomas maternos de infecção no primeiro trimestre de sua gravidez estiveram associados a uma redução mais acentuada no escore-z de PC nos primeiros três anos de vida dos participantes. A diminuição do escore-z de PC em crianças com SCZ nos primeiros 3 meses de sua vida monstra o potencial reduzido de crescimento e desenvolvimento do sistema nervoso central dessas crianças. O prognóstico de crescimento do perímetro cefálico nos primeiros 3 anos de vida é pior quando a infecção materna ocorreu no primeiro trimestre gestacional e em crianças que tiveram atrofia parênquimal grave.

Se conoce poco sobre la evolución del perímetro cefálico (PC) en niños con síndrome de Zika congénito (SZC) en los seguimientos continuos. El objetivo del estudio fue evaluar el crecimiento del PC en niños con SZC en los primeros 3 años de vida e identificar los factores asociados. Se recogieron datos del PC al nacimiento y obtenidos en las consultas de neuropediatría de 74 niños con SZC a partir de la Tarjeta del Niño, los informes de los padres y los registros médicos. Se investigaron los predictores de la puntuación Z del PC mediante diferentes modelos de efectos mixtos; se utilizó el criterio de información de Akaike para la selección del modelo. La puntuación Z del PC disminuyó de -2,7 ± 1,6 al nacer a -5,5 ± 2,2 a los 3 meses de edad, pero a partir de entonces se mantuvo relativamente estable. En el modelo ajustado seleccionado, la presencia de atrofia grave del parénquima cerebral y los síntomas maternos de infección en el primer trimestre del embarazo se asociaron con una reducción más pronunciada de la puntuación Z del PC en los primeros 3 años de vida. La disminución de la puntuación Z del PC en los niños con SZC durante los primeros 3 meses demuestra el menor potencial de crecimiento y desarrollo del sistema nervioso central de estos niños. El pronóstico del crecimiento de la cabeza en los primeros 3 años de vida es peor cuando la infección materna se produjo en el primer trimestre gestacional y en los niños que tenían una atrofia grave del parénquima cerebral.

Microcephaly measurement in adults and its association with clinical variables

ABSTRACT OBJECTIVE To establish a microcephaly cut-off size in adults using head circumference as an indirect measure of brain size, as well as to explore factors associated with microcephaly via data mining. METHODS In autopsy studies, head circumference was measured with an inelastic tape placed around the skull. Total brain volume was also directly measured. A linear regression was used to determine the association of head circumference with brain volume and clinical variables. Microcephaly was defined as head circumference that were two standard deviations below the mean of significant clinical variables. We further applied an association rule mining to find rules associating microcephaly with several sociodemographic and clinical variables. RESULTS In our sample of 2,508 adults, the mean head circumference was 55.3 ± 2.7cm. Head circumference was related to height, cerebral volume, and sex (p < 0.001 for all). Microcephaly was present in 4.7% of the sample (n = 119). Out of 34,355 association rules, we found significant relationships between microcephaly and a clinical dementia rating (CDR) > 0.5 with an informant questionnaire on cognitive decline in the elderly (IQCODE) ≥ 3.4 (confidence: 100% and lift: 5.6), between microcephaly and a CDR > 0.5 with age over 70 years (confidence: 42% and lift: 2.4), and microcephaly and males (confidence: 68.1% and lift: 1.3). CONCLUSION Head circumference was related to cerebral volume. Due to its low cost and easy use, head circumference can be used as a screening test for microcephaly, adjusting it for gender and height. Microcephaly was associated with dementia at old age.

Evaluation of the cephalometric centroid point in individuals before and after the pubertal growth peak / Avaliação do comportamento do ponto cefalométrico centróide em pacientes antes e após o pico de crescimento da puberdade

ABSTRACT Objective: The purpose of this study was to evaluate the behavior of the Centroid point, known as the geometric center of the face, before and after the growth peak using lateral cephalometric x-ray. Methods: Sample consisted of 40 patients before and after pubertal peak of growth selected from the archive of the São Leopoldo Mandic Institute and Research Center, Campinas, Brazil. Anatomical structures, reference points, lines and planes were traced, and posteriorly a superimposition was performed using the palatal plane and a line perpendicular to this passage through the most posterior point of the pterygomaxillary fossa as reference. Later, the distance between the two centroid points (before and after the peak of puberty) was measured using the digital caliper, both horizontally and vertically. The palatal plane (x-axis) and a line perpendicular to this passage through the most posterior point of the pterygomaxilary fossa (y-axis) were chosen because they undergo minimal changes during growth. Results: No significant difference on the location of Centroid points on both X and Y axis (p >0.05) were observed between before and after the growth peak cephalometric tracings, showing an average change in positioning of 0.36mm on the X axis and 0.37mm on the Y axis. Conclusions: For this reason, this point can be indicated to be used clinically as a stable reference to evaluate craniofacial growth while performing superimposition methods.

RESUMO Objetivo: O objetivo deste estudo foi utilizar telerradiografias lateriais de pacientes antes e depois do pico de crescimento, e realizar sobreposições de desenhos cefalométricos para avaliar o comportamento do ponto Centróide, o centro geométrico da face. Métodos: Foram selecionadas telerradiografias de norma lateral de 40 pacientes tomadas antes e depois de seu pico de puberdade do acervo de Ortodontia do Centro de Pesquisas Odontológicas São Leopoldo Mandic, na cidade de Campinas. As estruturas e traçados cefalométricos devidamente desenhados, foram sobrepostos tendo como referência estável o plano palatal e a linha perpendicular a esta que passe pelo ponto mais posterior da fossa pterigomaxilar. Em seguida foi medida a distância entre os dois pontos centroides (antes e após o pico de puberdade) por meio de paquímetro digital tanto no sentido horizontal quanto no vertical. O plano palatal (eixo x) e a linha perpendicular a esta que passe pelo ponto mais posterior da fossa pterigomaxilar (eixo y) foram escolhidos por sofrerem mínimas alterações nas suas direções durante o crescimento. Resultados: Não foi observada diferença estatisticamente significante na localização dos pontos Centróides em ambos os eixos X e Y (p>0,05) quando comparou-se os traçados antes e depois do pico de crescimento, mostrando uma alteração, em média, no posicionamento de 0,36mm no Eixo X e 0,37mm no Eixo Y. Conclusão: Assim, este ponto pode ser utilizado como referência estável para avaliação do crescimento craniofacial nas sobreposições.

Comparison of hyoid bone positions among patients with different sagittal skeletal malocclusions / 口腔疾病防治

Objective@# To compare the hyoid bone position among patients with different sagittal skeletal malocclusions to provide a reference for clinicians to formulate treatment plans.@*Methods@#Lateral cephalograms of 284 orthodontic patients were selected. According to ANB angles, the types of skeletal malocclusion of patients were determined as follows: Class Ⅰ (1° ≤ ANB ≤ 5°), Class Ⅱ (ANB>5°) and Class Ⅲ (ANB<1°). Ten parameters were used to determine hyoid positions. After comparing the hyoid positions of the three groups, stratified analyses based on sex and age were conducted. @*Results @# No significant differences in demographic and vertical facial type features among skeletal Classes Ⅰ, Ⅱ and Ⅲ patients were observed (P>0.05). The angle between the Gonion-hyoid point line and the hyoid point-Menton line (Go-Hy-Me) of Class Ⅱ patients was significantly smaller than that of Class Ⅰ patients, and the angle between the most anterior and inferior point of the third cervical vertebra-hyoid point line and the hyoid point-Sella line (C3-Hy-S) of Class Ⅲ patients was smaller than that of Class I patients (P<0.05). Age-stratified analysis showed that in the juvenile group, the C3-Hy-S of Class Ⅲ patients was significantly smaller than that of Class Ⅰ patients in males and females (P<0.05). In the adult female group, the Go-Hy-Me of Class Ⅱ patients was significantly smaller, and the distance from the hyoid point to the mandibular plane (Hy-MP) was larger than that noted in Class Ⅰ patients (P<0.05); no significant difference in hyoid position between male Class Ⅱ and I patients was observed (P>0.05).@*Conclusions@#Compared with Class Ⅰ patients, the hyoid bone of Class Ⅱ patients in adult females was farther away from the mandible and that of Class Ⅲ patients in juveniles was farther away from the cervical vertebra and posterior cranial base.

Efficacy of vertical control by using mini-implant anchorage in maxillary posterior buccal area for Angle class Ⅱ extraction patients / 北京大学学报(医学版)

OBJECTIVE@#To investigate the efficacy of vertical control by using conventional mini-implant anchorage in maxillary posterior buccal area for Angle class Ⅱ extraction patients.@*METHODS@#Twenty-eight Angle class Ⅱ patients [9 males, 19 females, and age (22.6±2.8) years] were selected in this study. All of these patients were treated by using straight wire appliance with 4 premolars extraction and 2 mini-implant anchorage in maxillary posterior buccal area. In this study, the self-control method was used to measure and analyze the lateral radiographs taken before and after orthodontic treatment in each case, the main cephalometric analysis items were related to vertical changes. The digitized lateral radiographs were imported into Dolphin Imaging Software (version 11.5: Dolphin Imaging and Management Solutions, Chatsworth, California, USA), and marked points were traced. Each marked point was confirmed by two orthodontists. The same orthodontist performed measurement on the lateral radiographs over a period of time. All measurement items were required to be measured 3 times, and the average value was taken as the final measurement result.@*RESULTS@#Analysis of the cephalometric radiographs showed that, for vertical measurements after treatment, the differences of the following measurements were highly statistically significant (P < 0.001): SN-MP decreased by (1.40±1.45) degrees on average, FMA decreased by (1.58±1.32) degrees on average, the back-to-front height ratio (S-Go/N-Me) decreased by 1.42%±1.43% on average, Y-axis angle decreased by (1.03±0.99) degrees on average, face angle increases by (1.37±1.05) degree on average; The following measurements were statistically significant (P < 0.05): the average depression of the upper molars was (0.68±1.40) mm, and the average depression of the upper anterior teeth was (1.07±1.55) mm. The outcomes indicated that there was a certain degree of upper molar depression after the treatment, which produced a certain degree of counterclockwise rotation of the mandibular plane, resulting in a positive effect on the improvement of the profile.@*CONCLUSION@#The conventional micro-implant anchorage in maxillary posterior buccal area has a certain vertical control ability, and can give rise to a certain counterclockwise rotation of the mandible, which would improve the profile of Angle Class Ⅱ patients.

Posición Natural de Cabeza y su relación con el Plano de Frankfurt en cefalometría ortodóncica

RESUMEN: Objetivo: el objetivo de este estudio fue determinar la discrepancia del Plano de Frankfurt evaluado en fotogrametría y en cefalometría de radiografías laterales de cráneo respecto a la horizontal verdadera. Materiales y métodos: el estudio consideró a 34 voluntarios de la clínica del Postítulo de Ortodoncia y Ortopedia Dento Máxilo Facial de la Facultad de Odontología de la Universidad de Chile. Se utilizaron sus radiografías laterales de cráneo orientadas según el Plano de Frankfurt paralelo al piso y se les tomó una fotografía facial de perfil estandarizada en Posición Natural de Cabeza. Se trazó el Plano de Frankfurt y la Horizontal Verdadera en ambos exámenes y se midió el ángulo formado entre estos planos. Resultados: al comparar los ángulos mediante T-test, no hubo diferencia estadística. Conclusiones: mediante la aplicación de un protocolo sistematizado tanto para el registro fotográfico como para la obtención de la Posición Natural de Cabeza, se puede lograr que el Plano de Frankfurt sea prácticamente coincidente en radiografías laterales de cráneo y en fotografías clínicas, demostrando su uso hasta el día de hoy en la ortodoncia moderna.

ABSTRACT: Objective: the aim of this study was to determine the Frankfurt plane variation evaluated in photogrammetry and lateral skull x-ray cephalometry in relation to the true horizontal. Materials and methods: the study included 34 volunteers from the Universidad de Chile Dento-maxillofacial Orthodontics and Orthopedics Postgraduate Clinic. Their lateral skull radiographs, oriented according to the Frankfurt Plane parallel to the floor, were used and a standardized profile facial photograph was taken in Natural Head Position. The Frankfurt Plane and True Horizontal were drawn in both examinations and the angle formed between these planes was measured. Results: when comparing the angles through T-test, there was no statistical difference. Conclusions: through the application of a systematized protocol for both photographic record and natural head position obtained, the Frankfurt Plane can be practically coincident in lateral skull x-rays and clinical photographs, showing its usefulness up to the present days in modern orthodontics.