Modificaciones del espacio óseo posterior para terceros molares desde la infancia hasta la adolescencia / Modifications of the posterior bony space for third molars from childhood to adolescence

Introducción: Del crecimiento de los maxilares depende en gran medida la correcta disposición de los dientes, especialmente de los terceros molares, que son los últimos en brotar. Objetivo: Estimar los cambios en el espacio óseo posterior según la edad y su relación con variables epidemiológicas. Métodos: Se realizó un estudio observacional, descriptivo y transversal en niños pertenecientes al Policlínico Docente "José Martí Pérez" de Santiago de Cuba, de mayo de 2016 a febrero de 2017, para lo cual se utilizaron radiografías panorámicas en las mediciones, analizadas según las variables edad, sexo y color de la piel. Resultados: Sobresalió que la diferencia del espacio óseo posterior de la infancia a la adolescencia fue de 9 mm para el molar 18, de 8,1 para el 28, de 12,5 para el 38 y de 11,5 para el 48; no se observaron diferencias significativas en cuanto a sexo y color de la piel. Conclusiones: Con la evaluación de la magnitud dimensional de dicho espacio es posible predecir el crecimiento de los maxilares para dar ubicación a los terceros molares en el transcurso de la infancia a la adolescencia.

Introduction: The correct disposition of teeth depends in great measure on the growth of maxillary, especially the third molars that are the last ones in eruption. Objective: To estimate the changes in the posterior bony space according to age and its relationship with epidemic variables. Methods: An observational, descriptive and cross-sectional study was carried out in children belonging to José Martí Pérez Teaching Polyclinic in Santiago de Cuba, from May, 2016 to February, 2017, for which panoramic X-rays were used in the measures, analyzed according to age, sex and color of the skin. Results: It was remarkable that the difference of the posterior bony space from childhood to adolescence was 9 mm for 18 molar, of 8.1 for 28 molar, of 12.5 for 38 molar and of 11.5 for 48 molar; significant differences were not observed between sex and color of the skin. Conclusions: With the evaluation of the dimensional magnitude of this space it is possible to predict the growth of the maxillary to give location to the third molars during the course from the childhood to the adolescence.

Características anatomorradiográficas de los terceros molares en adolescentes de la enseñanza preuniversitaria / Anatomo-radiographic characteristics of third molars in senior high school students

RESUMEN Introducción: Las retenciones dentarias afectan al 17 % de los pacientes a nivel mundial y están consideradas actualmente como un síndrome, en que los terceros molares ocupan el primer lugar y cuya extirpación quirúrgica deviene la intervención más comúnmente practicada por los cirujanos maxilofaciales. Objetivo: Describir las características anatomorradiográficas de los terceros molares, así como su posible relación con variables epidemiológicas de interés. Métodos: Se realizó un estudio observacional, descriptivo y transversal en escolares del Instituto Preuniversitario "Antonio Alomá Serrano", perteneciente al área de salud del Policlínico Docente Asistencial "José Martí" de Santiago de Cuba, durante el período comprendido desde mayo de 2016 hasta febrero de 2017. Se utilizaron radiografías panorámicas indicadas a estos pacientes, en las que se efectuaron el análisis y la clasificación. Resultados: La mayoría de los dientes se encontraban en clase I (52,6 por ciento), clase C (51,9 por ciento), posición C (82,2 por ciento), verticales (47,7 por ciento) y sin aproximación sinusal (89,5 por ciento). Además se observaron relaciones significativas entre la edad y el color de la piel con respecto al espacio retromolar y la inclinación dentaria de este grupo molar, y entre el sexo y la inclinación. Conclusiones: Los terceros molares son los dientes con mayor variabilidad en cuanto a posición e inclinación intraósea y en edades avanzadas se logra suficiente espacio retromolar y verticalización en la mayoría de ellos(AU)

ABSTRACT Introduction: Tooth impaction affects 17 % of patients worldwide. It is currently considered to be a syndrome in which third molars occupy the first place. Surgical removal is the most common intervention performed by maxillofacial surgeons. Objective: Describe the anatomo-radiographic characteristics of third molars and their possible relationship to epidemiological variables of interest. Methods: A cross-sectional observational descriptive study was conducted of students from Antonio Alomá Serrano Senior High School, from the health area of José Martí University Polyclinic in Santiago de Cuba, from May 2016 to February 2017. The study was based on panoramic radiographs, which were analyzed and classified. Results: Most teeth were class I (52.6 percent), class C (51.9 percent), position C (82.2 percent), vertical (47.7 percent) and without sinus approach (89.5 percent). Significant relationships were found between age and skin color with respect to retromolar space and tooth inclination of this molar group, and between sex and inclination. Conclusions: Third molars are the teeth showing the greatest variability in terms of intraosseous inclination and position. In advanced ages most of them achieve enough retromolar space and verticalization(AU)

Alterações da região retromolar decorrentes do crescimento mandibular / Retromolar space changes associated with mandibular growth

Objetivo: as modificações regionais inerentes ao processo de crescimento mandibular, como a reabsorção da borda anterior do ramo, determinam o aumento do espaço na região retromolar e mostram a necessidade ou não de exodontia dos terceiros molares. O objetivo deste trabalho foi avaliar, quantitativamente, o crescimento anteroposterior da região retromolar mandibular e verificar a ocorrência de dimorfismo sexual dessa variável. Material e métodos: foram utilizadas telerradiografias obtidas em norma lateral de 45 jovens, de ambos os sexos, leucodermas, entre nove e 11 anos de idade, mesofaciais, com perfis faciais harmônicos e oclusão normal. Foi aferido o espaço retromolar ao longo do plano oclusal funcional, entre a borda anterior do ramo da mandíbula e a face distal do primeiro molar inferior. Os dados obtidos submeteram-se, primeiramente, ao teste t de Student, para verificar o erro sistemático, e ao teste de correlação para o erro casual, ambos intraexaminador, indicando ausência de erro do método. Empregou-se o teste de Tukey, para comparar as medidas obtidas nas diferentes idades, e a análise de variância, para verificar a ocorrência de dimorfismo sexual. Resultados e conclusão: verificou-se um crescimento da região retromolar de 3,29 mm, entre os nove e os 11 anos. Nas idades de dez aos 11 anos ocorreu um aumento de 2,55 mm, sendo estatisticamente maior do que o constatado dos nove aos dez anos, de 0,74 mm. A análise de variância indicou ausência de dimorfismo sexual.

Objective: regional mandibular growth changes as the resorption of the anterior ramus border that increases the retromolar space determining if lower third molars need to be removed or not. The aim of this study was to evaluate, quantitatively, the mandibular alveolar sagital growth and also if sexual dimorphism was present. Material and methods: lateral cephalograms of 45 Brazilian Caucasian children of both genders, aging from 9 to 11 years, with balanced faces and good occlusion were used. The retromolar mandibular space was measured at the functional occlusal plane, from the anterior border of the ramus to the distal aspect of the lower first molar. The data was firstly examined about systematic and random intra-examiner errors through Student's "t" test and correlation test, respectively. In order to compare the data among different ages and occurrence of sexual dimorphism Anova and Tukey's test were performed. Results and conclusions: it was found an increase of 3.29 mm in the mandibular retromolar space from 9 to 11 years of age. Between 10 and 11 years there was an increase of 2.55 mm, statistically greater than those verified from 9 to 10 years of age, which was 0.74 mm. Anova demonstrated no sexual dimorphism.