ABSTRACT
BACKGROUND: When designing a treatment in orthodontics, especially for children and teenagers, it is crucial to be aware of the changes that occur throughout facial growth because the rate and direction of growth can greatly affect the necessity of using different treatment mechanics. This paper presents a Bayesian network approach for facial biotype classification to classify patients' biotypes into Dolichofacial (long and narrow face), Brachyfacial (short and wide face), and an intermediate kind called Mesofacial, we develop a novel learning technique for tree augmented Naive Bayes (TAN) for this purpose. RESULTS: The proposed method, on average, outperformed all the other models based on accuracy, precision, recall, [Formula: see text], and kappa, for the particular dataset analyzed. Moreover, the proposed method presented the lowest dispersion, making this model more stable and robust against different runs. CONCLUSIONS: The proposed method obtained high accuracy values compared to other competitive classifiers. When analyzing a resulting Bayesian network, many of the interactions shown in the network had an orthodontic interpretation. For orthodontists, the Bayesian network classifier can be a helpful decision-making tool.
Subject(s)
Algorithms , Awareness , Child , Adolescent , Humans , Bayes TheoremABSTRACT
OBJECTIVE: To describe and assess the available evidence of prediction methods of maxillary canine impaction (MCI). MATERIAL AND METHODS: A systematic search was conducted through PubMed, Cochrane Library, Embase, EBSCOhost, Scopus, ScienceDirect, Bireme and Scielo until December 2020. This systematic review was conducted according to the PRISMA statement. The methodology of the selected studies was assessed using the Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS-2). RESULTS: A total of 2391 articles were identified in the first approach and after a 2-phase selection, 11 studies were included in qualitative analysis. Prediction methods were constructed using equation-based models, geometric measurements and computational methods from clinical and imaging data to predict palatal/buccal MCI. The quality of evidence was low to moderate due to the presence of risk of bias in most of the studies included. Three cohort studies with the best methodological quality proposed prediction models based on geometric measurements, canine position and facial growth pattern that would allow predicting MCI from CBCT, lateral and panoramic radiographs. CONCLUSIONS: The evidence is limited and most of the studies present a low methodological quality. However, it is possible to suggest that some prediction methods based on the position of the canine and facial growth pattern could predict palatal/buccal MCI in mixed dentition. Cohort studies with better methodological quality and long-term follow-up are needed to better validate a prediction model.
Subject(s)
Cuspid , Tooth, Impacted , Humans , Radiography, Panoramic , Tooth, Impacted/diagnostic imagingABSTRACT
La higiene oral es fundamental en pacientes en tratamiento de ortodoncia. Actualmente hay una oferta amplia de cepillos eléctricos con este fin. El objetivo del presente estudio, fue determinar la eficacia y la comodidad del cep illo eléctrico Oral-B® Professional Care 500 en pacientes portadores de ortodoncia. Se realizó un ensayo clínico, randomizado, doble ciego, unicéntrico, con una muestra de 90 pacientes, divididos en dos grupos: 45 pacientes utilizaron cepillo eléctrico y 45 sujetos utilizaron cepillos manuales durante 90 días. Se determinó la efectividad con los índices O'leary, índice de placa de bracket e índice de Eastman al inicio, a los 30 y a los 90 días de uso de los cepillos y se evaluó la comodidad del cepillo eléctrico mediante una encuesta de satisfacción al término del estudio. Al analizar los datos, se observó una disminución significativa en los índices de O'leary y de placa de bracket en ambos grupos,mientras que se observó una disminución significativa en el índice de Eastman sólo en el grupo que utilizó el cepillo eléctrico. El resultado de la encuesta, indica qu e, en opinión de los participantes del estudio, el cepillo eléctrico es cómodo, fácil de usar y recomendable para pacientes con aparatología fija. En conclusión, el cepillo eléctrico Oral-B® Professional Care 500 resultó ser efectivo y cómodo al ser usado por pacientes portadores de ortodoncia fija y puede ser recomendado para este tipo de pacientes.
Oral hygiene is essential in patients undergoing orthodontic treatment. Currently there is a wide offer of electric brushes for this purpose. The objective of this study is to determine the efficacy and comfort of the Oral-B® Professional Care 500 electric toothbrush in orthodontic wearers. A double-blind, single-center clinical trial was carried out, in which the sample was 90 patients, these were randomized into two groups: 45 patients with electric toothbrush treatment and 45 subjects with manual toothbrush treatment. The effectiveness was determined with the O'leary indexes, the bracket plate index and the Eastman index. For the evaluation of comfort, a survey was used. Statistical analysis was performed with the Shapiro-Wilks test and the Mann-Whitney U test, in which a significant decrease was found in the O'leary index and bracket plate index in the group that used the electro-oscillating brush rotary and a greater decrease in the Eastman index was observed in the same group. In conclusion, the electric toothbrush is comfortable and easy to use, recommended for patients with fixed appliances.
Subject(s)
Humans , Orthodontics , Toothbrushing , Single-Blind Method , Dental Plaque Index , Oral Health , Surveys and Questionnaires , Data Interpretation, Statistical , Dental Plaque/prevention & control , Patient ComfortABSTRACT
El realizar un tratamiento ortodóntico sólo en base a referencias de tejidos duros, puede llevar a resultados estéticos desfavorables, debido a la gran variabilidad que existe en los tejidos blandos que los recubren. Arnett et al. (1999) presentaron un análisis basado en los tejidos blandos y determinó normas que definen un rostro armónico. Sin embargo, éstas normas se obtuvieron de pacientes norteamericanos y puede que no reflejen los conceptos estéticos de nuestra población. El objetivo del presente trabajo fue determinar valores de armonía facial para la población chilena, utilizando el análisis cefalométrico de tejidos blandos presentado por Arnett et al., y compararlos con los valores previamente establecidos para la población caucásica. Se analizaron 200 fotografías y se clasificaron los perfiles en balanceados y no balanceados según el criterio de un grupo de especialistas. Posteriormente se analizaron las telerradiografías correspondientes a los perfiles clasificados, con el análisis cefalométrico de tejidos blandos. Los valores de las diferentes variables fueron analiza dos separadamente por sexo, clase esqueletal y biotipo facial, y se determinaron las diferencias entre las variables presentadas por Arnett et al. y las obtenidas en el presente estudio. Para ello se utilizaron pruebas de significancia estadística como el test t y otros no paramétricos. Sólo se encontró diferencias significativas en dos variables respecto de las normas sugeridas por Arnett et al., correspondientes a un menor espesor del labio inferior en ambos sexos, y una mayor prominencia del pómulo en mujeres chilenas, por lo que consideramos que los valores de armonía de Arnett et al., pueden ser también aplicados como parámetro estético para la población chilena.
Performing an orthodontic treatment based only on hard tissue references can lead to unfavorable aesthetic results due to the great variability that exists in soft tissues that cover them. In 1999, W.Arnett, presented an analysis based on soft tissues and determined norms that define a harmonious face. However, these standards that were obtained from North Americans and Chilean aesthetic concepts could be different. The aim of the study was to determine the values of facial harmony for the Chilean population, using the cephalometric analysis of soft tissues presented by Arnett, and compare them with the values previously established for the Caucasian population. In this study 200 photographs were analyzed, and the profiles were classified in balanced and unbalanced according to the criteria of a group of specialists. Subsequently, teleradiographs corresponding to the classified profiles were analyzed, with the cephalometric analysis of soft tissues. The values of the different variables were analyzed separately by sex, skeletal class and facial biotype, and the differences between the variables presented by Arnett et al., and those obtained in the present study. For this purpose, statistical significance tests such as the t test and other non- parametric tests were used. There were only significant differences in two variables: inferior lip variables in both sexes, and a greater prominence of the cheekbone in Chilean women, therefore we consider that the values of harmony of Arnett, can also be applied as an aesthetic parameter for the Chilean population.
Subject(s)
Humans , Female , Pregnancy , Young Adult , Cephalometry , Face/anatomy & histology , Reference Values , Chile , Sex Characteristics , Photography, Dental , Esthetics, DentalABSTRACT
OBJECTIVE: To evaluate the validity of craniofacial growth predictors in class II and III malocclusion. MATERIAL AND METHODS: An electronic search was conducted until August 2020 in PubMed, Cochrane Library, Embase, EBSCOhost, ScienceDirect, Scopus, Bireme, Lilacs and Scielo including all languages. The articles were selected and analyzed by two authors independently and the selected studies was assessed using the 14-item Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS-2). The quality of evidence and strength of recommendation was assessed by the GRADE tool. RESULTS: In a selection process of two phases, 10 articles were included. The studies were grouped according to malocclusion growth predictor in (1) class II (n = 4); (2) class III (n = 5) and (3) class II and III (n = 1). The predictors were mainly based on data extracted from cephalometries and characterized by: equations, structural analysis, techniques and computer programs among others. The analyzed studies were methodologically heterogeneous and had low to moderate quality. For class II malocclusion, the predictors proposed in the studies with the best methodological quality were based on mathematical models and the Fishman system of maturation assessment. For class III malocclusion, the Fishman system could provide adequate growth prediction for short- and long-term. CONCLUSIONS: Because of the heterogeneity of the design, methodology and the quality of the articles reviewed, it is not possible to establish only a growth prediction system for class II and III malocclusion. High-quality cohort studies are needed, well defined data extraction from cephalometries, radiographies and clinical characteristics are required to design a reliable predictor.
Subject(s)
Malocclusion, Angle Class III , Malocclusion, Angle Class II , Malocclusion , Cephalometry , Humans , Malocclusion, Angle Class II/diagnosis , Malocclusion, Angle Class III/diagnosisABSTRACT
Resumen Introducción: La obesidad es un problema a nivel global que enfrenta el siglo XXI y Chile no se escapa de esta realidad. Así como existen características mórbidas de pacientes con obesidad, también existen características craneofaciales similares en estos pacientes. El estado nutricional es un factor que influencia el desarrollo de una persona en general, lo que tiene implicancias en el tratamiento ortodóncico, ortopédico y quirúrgico de las alteraciones maxilo - mandibulares de los pacientes. Objetivo: Investigar si la morfología craneofacial difiere entre los adolescentes obesos y los de peso normal. Métodos: Estudio retrospectivo, se basó en la comparación de medidas craneofaciales obtenidas del análisis cefalométrico, utilizando teleradiografías laterales, de dos grupos: grupo estudio (IMC mayor a 30, obeso) y grupo control (IMC normal). Resultados: Se observaron dimensiones maxilares y mandibulares mayores en el grupo estudio comparado con los pacientes del grupo control. Las medidas para la dimensión maxilar tuvieron diferencia significativamente estadística. Conclusiones: El aumento de peso es un factor importante que puede afectar los patrones de crecimiento craneofacial y debe ser tomado en consideración durante la planificación del tratamiento ortodoncico en pacientes adolescentes.
Abstract Introduction: Obesity is a global problem in the the 21st century and Chile does not escape this reality. Just as there are morbid characteristics of patients with obesity, there also share similar craniofacial characteristics. Nutritional status is a factor that influences the a person´s general development , which has implications in the orthodontic, orthopedic and surgical treatments of maxillo-mandibular alterations. Objective: Investigate whether craniofacial morphology differs between obese and average-weight adolescents. Methods: A retrospective study based on the comparison of craniofacial measures obtained from the cephalometric analysis, using lateral cephalograms, from two groups: study group (BMI over 30, obese) and control group (normal BMI). Greater maxillary and mandibular dimensions were observed in the study group compared to the patients in the control group. The measurements for de maxillary dimension had a statistically significant difference. Conclusions: Weight gain is an important factor that can affect craniofacial growth patterns and should be taken into consideration during the planning of orthodontic treatment in adolescent patients.
Subject(s)
Humans , Male , Female , Adolescent , Cephalometry/classification , Obesity/diagnosis , Chile , Craniofacial Abnormalities , Mandible/anatomy & histologyABSTRACT
The aim of this study was to validate and correlate the two-dimensional (2D) with the three-dimensional (3D) measures of the upper airway assessment. Lateral cephalograms and cone beam CT of 100 adult subjects were used to perform a 2D and 3D assessment of the upper airway. Spearman correlation coefficient was used to determine whether there was correlation between variables. Additionally, specificity, sensitivity, negative predictive value and positive predictive value was calculated for the 2D assessment of the upper airway. Correlation between all two and three dimensional variables was found. In the nasopharynx and oropharynx, a weak correlation (r <0.51) was found; in the oropharynx a moderate one (0.50
El objetivo de este estudio fue validar y correlacionar las medidas bidimensionales (2D) con las medidas tridimensionales (3D) de la evaluación de las vías aéreas superiores. Se realizaron cefalogramas laterales y cone beam CT en 100 sujetos adultos para realizar una evaluación 2D y 3D de la vía aérea superior. Se utilizó el coeficiente de correlación de Spearman para determinar si había correlación entre las variables. Además, para la evaluación 2D de la vía aérea superior, se calculó la especificidad, sensibilidad, valor predictivo negativo y valor predictivo positivo. Se encontró correlación en todas las variables entre dos y tres dimensiones. En la nasofaringe y la orofaringe, se encontró una correlación débil (r <0,51) mientras que en la orofaringe moderada (0,50 Subject(s)
Humans
, Male
, Female
, Adolescent
, Adult
, Middle Aged
, Young Adult
, Cephalometry/methods
, Cone-Beam Computed Tomography
, Imaging, Three-Dimensional
, Oropharynx/diagnostic imaging
, Cross-Sectional Studies
, Hypopharynx/anatomy & histology
, Hypopharynx/diagnostic imaging
, Imaging, Three-Dimensional
, Nasopharynx/anatomy & histology
, Nasopharynx/diagnostic imaging
, Oropharynx/anatomy & histology
, Predictive Value of Tests
, Sensitivity and Specificity
ABSTRACT
Objetivo: Determinar la exactitud del Índice de Tanaka-Johnston e Índice de Moyers mediante el análisis de modelos de estudio iniciales con dentición definitiva de pacientes chilenos del Postgrado de Ortodoncia de la Universidad Andrés Bello sede Santiago. Materiales y métodos: Se seleccionaron por conveniencia 100 pares de modelos según los criterios de inclusión y exclusión establecidos, correspondientes 50 al género femenino y 50 al masculino, y se realizó medición directa con un pie de metro manual, de la suma incisiva inferior y suma de segmentos canino-premolar. La medición fue realizada por dos examinadores previamente calibrados. Se determinó la exactitud de cada uno de los métodos y presencia de diferencias estadísticas significativas. Resultados: Para mujeres, Moyers 65% en maxilar superior y Moyers 50% en maxilar inferior presentan mayor exactitud en predicción de tamaño mesiodistal de caninos y premolares permanentes no erupcionados; en cambio, para hombres, Moyers 75% en maxilar superior y Moyers 65% en maxilar inferior son más exactos. El método de Tanaka-Johnston a pesar que solo presenta diferencias estadísticamente significativas en maxilar inferior en el género femenino (p<0,05), es menos exacto tendiendo a sobrestimar valores reales en mujeres, y a subestimar en hombres. Conclusión: Método de Moyers es más exacto en la predicción del espacio necesario en pacientes chilenos, su nivel de confianza varía según género y maxilar. Diferencias son explicadas por dimorfismo sexual y variaciones étnicas con respecto a la población de origen de métodos de predicción.
Objetive: Determine the accuracy of Tanaka-Johnston and Moyers indexes through the initial analysis of study models with permanent teeth of Chilean patients of the Graduate School Orthodontics of University Andres Bello in Santiago. Materials and Methods: 100 pairs of models were selected by convenience as the inclusion and exclusion criteria established, corresponding to 50 female and 50 male. Direct measurement was performed with a manual caliper gauge by two examiners previously calibrated. The sum of permanent mandibular incisors and sum of segments canine-premolar were measured. The accuracy of each of the present methods and statistical differences were determined. Results: In females, the prediction of width of unerupted canines and premolars is more accurate on maxilla with Moyers 65% and mandible with Moyers 50%. For males, Moyers 75% on maxilla and Moyers 65% in mandible are more accurate. Tanaka-Johnston method although only presented statistically significant differences in mandible of female gender (p <0.05), is less accurate tending to overestimate actual values in women as in men underestimated. Conclusion: Moyers method is more accurate in predicting space required in Chilean patients, the confidence level varies according to gender and jaw. Differences are explained by sexual dimorphism and ethnic variations from the source population of prediction methods.
ABSTRACT
Introducción: La obesidad es un problema a nivel global que enfrenta el siglo XXI y Chile no se escapa de esta realidad. Así como existen características mórbidas de pacientes con obesidad, también existen características craneofaciales similares en estos pacientes. El estado nutricional es un factor que influencia el desarrollo de una persona en general, lo que tiene implicancias en el tratamiento ortodóncico, ortopédico y quirúrgico de las alteraciones maxilo - mandibulares de los pacientes. Objetivo: Investigar si la morfología craneofacial difiere entre los adolescentes obesos y los de peso normal. Métodos: Estudio retrospectivo, se basó en la comparación de medidas craneofaciales obtenidas del análisis cefalométrico, utilizando teleradiografías laterales, de dos grupos: grupo estudio (IMC mayor a 30, obeso) y grupo control (IMC normal). Resultados: Se observaron dimensiones maxilares y mandibulares mayores en el grupo estudio comparado con los pacientes del grupo control. Las medidas para la dimensión maxilar tuvieron diferencia significativamente estadística. Conclusiones: El aumento de peso es un factor importante que puede afectar los patrones de crecimiento craneofacial y debe ser tomado en consideración durante la planificación del tratamiento ortodoncico en pacientes adolescentes.
Introduction: Obesity is a global problem in the the 21st century and Chile does not escape this reality. Just as there are morbid characteristics of patients with obesity, there also share similar craniofacial characteristics. Nutritional status is a factor that influences the a person´s general development , which has implications in the orthodontic, orthopedic and surgical treatments of maxillo-mandibular alterations. Objective: Investigate whether craniofacial morphology differs between obese and average-weight adolescents. Methods: A retrospective study based on the comparison of craniofacial measures obtained from the cephalometric analysis, using lateral cephalograms, from two groups: study group (BMI over 30, obese) and control group (normal BMI). Greater maxillary and mandibular dimensions were observed in the study group compared to the patients in the control group. The measurements for de maxillary dimension had a statistically significant difference. Conclusions: Weight gain is an important factor that can affect craniofacial growth patterns and should be taken into consideration during the planning of orthodontic treatment in adolescent patients.
ABSTRACT
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.
Subject(s)
Humans , Male , Female , Child , Adolescent , Anatomic Landmarks/anatomy & histology , Cephalometry/methods , Skull/anatomy & histology , Skull/growth & developmentABSTRACT
The aim was to find craniofacial morphology patterns in a multivariate cephalometric database using a clustering technique. Cephalometric analysis was performed in a sample of 100 teleradiographs collected from Chilean orthodontic patients. Thirty cephalometric measurements were taken from commonly used analysis. The computed variables were used to perform a clustering analysis with the k-means algorithm to identify patterns of craniofacial morphology. The J48 decision tree was used to analyze each cluster, and the ANOVA test to determine the statistical differences between the clusters. Four clusters were found that had significant differences (P<0.001) in 24 of the 30 variables studied, suggesting that they represent different patterns of craniofacial form. Using the decision tree, 8 of the 30 variables appeared to be relevant for describing the clusters. The clustering analysis is effective in identifying different craniofacial patterns based on a multivariate database. The distinct clusters appear to be caused by differences in the compensation process of the facial structure responding to a genetically determined cranial and mandible form. The proposed method can be applied to several databases, creating specific classifications for each one of them.
El objetivo fue encontrar patrones morfológicos craneofaciales, a partir de una base de datos cefalométricos multivariada, utilizando una técnica de clustering. Se realizó un análisis cefalométrico a una muestra de 100 telerradiografías pertenecientes a pacientes chilenos de ortodoncia. Treinta medidas cefalométricas obtenidas de los análisis más utilizados fueron registradas. Las variables computadas se utilizaron para realizar un análisis de clustering con el algoritmo k-medias, para identificar patrones de morfología craneofacial. El árbol de decisión J48 se utilizó para analizar cada cluster, y test de ANOVA para determinar diferencias estadísticamente significativas entre los clusters. Se encontraron cuatro clusters con diferencia estadísticamente significativas (p<0,001) en 24 de las 30 variables estudiadas, lo que sugiere que efectivamente corresponden a diferentes patrones craneofaciales. Utilizando el árbol de decisión, se pudo determinar que 8 de las 30 variables resultaron ser relevantes en la definición de los clusters. El análisis de clustering es efectivo en identificar patrones morfológicos craneofaciales usando una base de datos multivariada. Los distintos cluster encontrados, aparentemente se formarían a partir de diferencias en el proceso de compensación de la estructura facial, en respuesta a la forma mandibular genéticamente determinada. El método propuesto puede ser aplicado a múltiples bases de datos, creando clasificaciones específicas para cada una de ellas.
Subject(s)
Humans , Male , Female , Face/anatomy & histology , Cephalometry/methods , Skull/anatomy & histology , Decision Making , Orthodontics/methods , Analysis of VarianceABSTRACT
El objetivo fue determinar la existencia de asimetría vertical mandibular, en pacientes con mordida cruzada posterior uni y bilateral, tanto en dentición mixta primera fase como en permanente completa. Se recolectaron radiografías panorámicas correspondientes a 121 pacientes con dentición mixta primera fase y permanente completa, 57 de los cuales, presentaba mordida cruzada unilateral, 21 mordida cruzada bilateral y 43 individuos con oclusión normal, que sirvieron como grupo control. En las radiografías, se cuantificaron medidas lineales de altura condilar, coronoidea, de rama, cóndilo-más-rama y la diferencia entre las alturas de cóndilo y coronoides. Además, se calcularon los índices de asimetría para cada una de dichas estructuras. Se determinó la existencia de diferencias significativas entre los grupos, mediante el cálculo de los test Mann-Whitney y Kruskal-Wallis, dada la distribución de las variables y un test de chi cuadrado para evaluar asociación entre las mismas, con un intervalo de confianza de 95 por ciento (p<,05). Existen diferencias significativas entre los índices de rama y de cóndilo-más-rama, entre el grupo control y el grupo con mordida cruzada unilateral (MCU), al igual que en el índice coronoideo, entre el grupo control y el grupo con mordida cruzada bilateral. El grupo con MCU, presentó un mayor porcentaje de pacientes con asimetría de cóndilo y rama, encontrándose una leve asociación entre la condición de mordida cruzada unilateral y la asimetría de dichas estructuras. Dados los resultados, se puede concluir que existe asimetría en el cóndilo, coronoides y en cóndilo-menos-coronoides y coronoides, tanto en pacientes con mordida cruzada uni como bilateral. Sin embargo, el grupo con MCU presenta un mayor porcentaje de pacientes con asimetría de cóndilo y rama, existiendo una leve asociación entre MCU y asimetría de dichas estructuras...
The aim was to evaluate the mandibular vertical asymmetry, in unilateral and bilateral posterior crossbite patients both in permanent and mixed dentition. One hundred twenty one panoramic radiographs were collected, 57 from patients with unilateral posterior crossbite, 21 patients with bilateral posterior crossbite and 43 with normal occlusion that were used as a control group. Subsequently, reference points and cephalometric traces were drawn manually by a calibrated examiner in order to register the condylar, coronoideal, and ramal heigths. This data was used to calculate an asymmetry index for each structure. According to the distribution of the variables, Mann-Whitney and Kruskal-Wallis test was used to compare the data between groups of patients and chi square was used to evaluate association between them, at the 95 percent confidence interval (p<.05). Statistically significant differences were found in the ramal and condylar-plus-ramal asymmetry index values, between the control and the unilateral posterior crossbite group, also statistical differences were found in the coronoideal index values, between the control and the bilateral posterior crossbite groups. On the other hand, the bilateral crossbite group, presented a higher percentage of patients with condylar and ramal asymmetry, finding a mild statistically significant association between this condition and those with asymmetry. Condylar and coronoideal asymmetry was found both in the unilateral as in the unilateral posterior crossbite patients. The bilateral crossbite group, presented a major percentage of patients with asymmetry, with a mild association between those conditions...