Does height catch-up in schoolchildren have an effect on bone mass in adolescents? Analysis in a Brazilian birth cohort / Catch-up de estatura em escolares tem efeito sobre massa óssea em adolescentes? Análise em uma coorte brasileira de nascimento

Abstract Objective: To analyze the effect of height catch-up at school age on the bone mass of adolescents of a Brazilian birth cohort. Methods: A cohort study using data obtained from the three moments (birth, 7/9 years and 18/19 years of age) of the Cohorts-RPS study. Height catch-up was defined based on the difference between the schoolchild's z-score and birth z-score. The adolescents' bone mineral mass was analyzed using the z-score index for the lumbar spine measured by dual emission X-ray absorptiometry. A theoretical model was developed for the proposed analysis using directed acyclic graphs paired through the nearest-neighbor matching propensity score using the STATA software, version 14.0. The level of significance was set at 5%. Results: Of the 297 studied children, 24.5% achieved height catch-up. The bone mass below the expected for age was observed in 5.39% of the subjects. The mean lumbar spine z-score was −0.34 (±1.01). After the adjustment, no effect was observed between height catch-up at school age and bone mass in adolescents (Coeff = 0.598; 95% CI −0.117 to 1.313; p = 0.101). Conclusion: Even using the directed acyclic graphs and the causal inference method by adjusting the propensity score, the height catch-up did not seem to affect bone mass in adolescents, a result perhaps related to the sample size.

Resumo: Objetivo: Analisar o efeito do catch-up de estatura na idade escolar na massa óssea em adolescentes em uma coorte brasileira de nascimento. Métodos: Estudo de coorte, utilizando dados dos três momentos (nascimento, aos 7/9 anos e 18/19 anos) da pesquisa Coortes-RPS. Catch-up de estatura foi definida a partir da diferença entre o Z-score do escolar e Z-score do nascimento. Para a análise da massa óssea em adolescentes foi utilizado o índice Z-score da coluna lombar medido pela densitometria por dupla emissão de raio X. Para análise proposta, foi construído modelo teórico usando os gráficos acíclicos direcionados e pareado por escore de propensão do tipo vizinho mais próximo utilizando o software STATA versão 14.0. O nível de significância adotado foi de 5%. Resultados: Das 297 crianças, 24,58% realizaram o catch-up estatural. Massa óssea abaixo do esperado para a idade foi de 5,39%. O Z-score médio da coluna lombar foi −0,34 (± 1,01). Após ajuste, não foi observado efeito entre catch-up de estatura na idade escolar e massa óssea no adolescente (Coef = 0,598; IC 95% −0,117-1,313; p = 0,101). Conclusão: Mesmo com os gráficos acíclicos direcionados e o método de inferência causal por ajuste do escore de propensão, o catch-up de estatura parece não afetar a massa óssea em adolescentes, resultado talvez relacionado ao tamanho da amostra.

La singularidad de los maxilares dentro del sistema esquelético / Singularity of the jaws within the skeletal system

En la odontología es frecuente que se describa la peculiaridad de los huesos maxilares en cuanto a la resistencia a las infecciones en comparación con otros huesos de la economía. O que se plantée un desafío cuando es necesario tomar una decisión acerca de aplicar diferentes conductas terapéuticas en pacientes con patologías óseas sistémicas. Por ello, esta actualización tuvo como objetivo realizar una revisión de la bibliografía para integrar y evidenciar las diferencias y similitudes entre los diferentes huesos de la economía haciendo hincapié en los huesos maxilares. Si bien éstos poseen una gran cantidad de similitudes con el resto de los huesos, también presentan diferencias que los hacen entidades únicas dentro del sistema esquelético como el origen embriológico en las células de las crestas neurales, su alta tasa de remodelación, sin olvidar que estos huesos alojan a órganos que poseen una parte de su estructura en el medio interno y otra porción en medio externo de la cavidad bucal: las piezas dentarias (AU)

Historias de vida y demografía de Physalaemus biligonigerus (Anura: Leptodactylidae) en una charca periurbana del centro de Argentina / Demography and life histories of Physalaemus biligonigerus (Anura: Leptodactylidae) in a peri-urban pond in central Argentina

Resumen El conocimiento de la dinámica de poblaciones provee información sobre la historia reciente, el estado actual y la tendencia futura de una población. Physalaemus biligonigerus es un anuro con una amplia distribución en el Neotrópico, presenta una actividad reproductiva elevada y explosiva, pero sus poblaciones parecen estar compuestas por individuos jóvenes. El objetivo de este estudio fue analizar la demografía poblacional de P. biligonigerus en una charca semipermanente en Río Cuarto, Córdoba, Argentina y realizar una proyección poblacional a 30 generaciones. Se determinó la estructura de edad utilizando esqueletocronología, y posteriormente se construyó una tabla de vida estática. Se calculo la fecundidad y las tasas de supervivencia para cada estadío con los que se construyó una Matriz de Leslie y se realizó la proyección poblacional. La proyección muestra oscilaciones en el número de individuos pero a pesar de esto, la tendencia final de la población es a un aumento en su tamaño. La mayor proporción de supervivientes se da en las fases de huevos a larvas, y la fuerza de mortalidad actúa con intensidad sobre la fase de larvas. La tasa neta reproductiva indica que la población de P. biligonigerus de la charca en estudio está en incremento.

Abstract Knowledge of population dynamics provides information on the recent history, current status, and future trends of a population. Physalaemus biligonigerus is widely distributed in the Neotropics, this anuran has a high and explosive reproductive activity, but its populations seem to be composed of young individuals. The objective of this study was to analyze the population demography of P. biligonigerus in a semipermanent pond in Río Cuarto, Córdoba, Argentina and to carry out a population projection through 30 generations. The age structure was determined from the use of skeletochronology, and a static life table was later made. Fertility and survival rates were calculated for each stage, by which a Leslie Matrix was constructed and the population projection was performed. The projection shows oscillations in the number of individuals but in spite of this, the final tendency of the population is an increase in its size. The highest proportion of survivors occurs in the egg-to-larval stages and the mortality force acts intensively on the larval phase. The net reproductive rate indicates that the population of P. biligonigerus of the study pond is increasing. Rev. Biol. Trop. 66(2): 765-775. Epub 2018 June 01.

Relationship between dental calcification and skeletal maturation in a Peruvian sample

ABSTRACT Objective: the objective of the study was to determine the relationship between dental calcification stages and skeletal maturation in a Peruvian sample. Methods: panoramic, cephalometric and carpal radiographs of 78 patients (34 girls and 44 boys) between 7 and 17 years old (9.90 ± 2.5 years) were evaluated. Stages of tooth calcification of the mandibular canine, first premolar, second premolar, and second molar and the skeletal maturation with a hand-wrist and a cervical vertebrae method were assessed. The relationships between the stages were assessed using Spearman's correlation coefficient. Additionally, the associations of mandibular and pubertal growth peak stages with tooth calcification were evaluated by Fisher's exact test. Results: all teeth showed positive and statistically significant correlations, the highest correlation was between the mandibular second molar calcification stages with hand-wrist maturation stages (r = 0.758, p < 0.001) and with vertebrae cervical maturation stages (r = 0.605, p < 0.001). The pubertal growth spurt was found in the G stage of calcification of the second mandibular molar, and the mandibular growth peak was found in the F stage of calcification of the second molar. Conclusion: there was a positive relationship between dental calcification stages and skeletal maturation stages by hand-wrist and cervical vertebrae methods in the sample studied. Dental calcification stages of the second mandibular molar showed the highest positive correlation with the hand-wrist and cervical vertebrae stages.

RESUMO Objetivo: o objetivo do presente estudo foi determinar a correlação entre o estágio de calcificação dentária e a maturação esquelética, em uma amostra de indivíduos peruanos. Métodos: radiografias panorâmicas, cefalométricas e carpais de 78 pacientes (34 meninas e 44 meninos) com idades entre 7 e 17 anos (média = 9,90 ± 2,5 anos) foram avaliadas. Nelas, avaliaram-se os estágios de calcificação dentária (canino, primeiro pré-molar, segundo pré-molar e segundo molar inferiores) e de maturação esquelética, pelas avaliações radiográficas da mão e punho e das vértebras cervicais. As correlações entre esses estágios foram avaliadas usando-se o coeficiente de correlação de Spearman. Adicionalmente, a associação entre os estágios em que ocorreram os picos de crescimento mandibular e de crescimento puberal e o grau de calcificação dentária foi avaliada pelo teste exato de Fisher. Resultados: todos os dentes demonstraram correlações positivas e estatisticamente significativas. A correlação mais elevada foi verificada entre o estágio de calcificação do segundo molar inferior e o estágio de maturação esquelética da mão e do punho (r= 0,758, p < 0,001) e o estágio de maturação das vértebras cervicais (r = 0,605, p < 0,001). O surto de crescimento puberal foi identificado no estágio G de calcificação do segundo molar inferior, e o pico de crescimento mandibular foi detectado no estágio F de calcificação do segundo molar. Conclusão: na amostra estudada, houve uma correlação positiva entre os estágios de calcificação dentária e os estágios de maturação esquelética avaliada nas radiografias de mão e punho e das vértebras cervicais. Os estágios de calcificação dentária do segundo molar inferior demonstraram a mais alta correlação positiva com os estágios de maturação da mão e punho e das vértebras cervicais.

Somatic maturation and the relationship between bone mineral variables and types of sports among adolescents: cross-sectional study / Maturação somática e o relacionamento entre variáveis minerais ósseas e modalidades esportivas em adolescentes: estudo transversal

ABSTRACT CONTEXT AND OBJECTIVE: Peak height velocity (PHV) is an important maturational event during adolescence that affects skeleton size. The objective here was to compare bone variables in adolescents who practiced different types of sports, and to identify whether differences in bone variables attributed to sports practice were dependent on somatic maturation status. DESIGN AND SETTING: Cross-sectional study, São Paulo State University (UNESP). METHODS: The study was composed of 93 adolescents (12 to 16.5 years old), divided into three groups: no-sport group (n = 42), soccer/basketball group (n = 26) and swimming group (n = 25). Bone mineral density and content were measured using dual-energy x-ray absorptiometry and somatic maturation was estimated through using peak height velocity. Data on training load were provided by the coaches. RESULTS: Adolescents whose PHV occurred at an older age presented higher bone mineral density in their upper limbs (P = 0.018). After adjustments for confounders, such as somatic maturation, the swimmers presented lower values for bone mineral density in their lower limbs, spine and whole body. Only the bone mineral density in the upper limbs was similar between the groups. There was a negative relationship between whole-body bone mineral content and the weekly training hours (β: -1563.967; 95% confidence interval, CI: -2916.484 to -211.450). CONCLUSION: The differences in bone variables attributed to sport practice occurred independently of maturation, while high training load in situations of hypogravity seemed to be related to lower bone mass in swimmers.

RESUMO CONTEXTO E OBJETIVO: O pico de velocidade de crescimento (PVC) constitui importante evento maturacional durante a adolescência, afetando o tamanho do esqueleto. O objetivo do estudo foi comparar variáveis ósseas em adolescentes praticantes de diferentes modalidades esportivas, bem como identificar se diferenças nas variáveis ósseas atribuídas à prática esportiva são dependentes do estado da maturação somática. DESENHO E LOCAL: Estudo transversal, Universidade Estadual Paulista (UNESP). MÉTODOS: O estudo foi constituído por 93 adolescentes (12 a 16,5 anos), divididos em três grupos: grupo sem envolvimento esportivo (n = 42), futebol/basquete (n = 26) e natação (n = 25). A densidade e conteúdo mineral ósseo foram mensurados utilizando absortiometria de raio-x de dupla energia e a maturação somática foi estimada através do uso do PVC. Informações sobre volume de treinamento foram fornecidas pelos treinadores. RESULTADOS: Adolescentes com idade tardia no PVC apresentaram maiores valores de densidade mineral óssea em membros superiores (P = 0,018). Após ajustes por variáveis de confusão, como a maturação somática, os nadadores apresentaram menores valores de densidade mineral óssea em membros inferiores, coluna e corpo inteiro. Apenas a densidade mineral óssea de membros superiores foi similar entre os grupos. Existiu relação negativa entre conteúdo mineral ósseo de corpo inteiro e tempo de treino semanal (β: -1563.967; 95% intervalo de confiança, IC: -2916.484 a -211.450). CONCLUSÃO: As diferenças em variáveis ósseas atribuídas à prática esportiva ocorrem independentemente da maturação, enquanto elevada quantidade de treinamento em situações de hipogravidade parece estar relacionada com menor massa óssea em nadadores.

Morphology, development and heterochrony of the carapace of giant amazon river turtle podocnemis expansa (testudines, podocnemidae) / Morfologia, desenvolvimento e heterocronia da carapaça da tartagura da amazônia, podocnemis expansa (testudines, podocnemidae)

With aim to report the ontogeny of the osseous elements of the carapace in Peurodiras, 62 embryos and 43 nestlings of Podocnemis expansa were collected and submitted to the clearing and staining technique of bones and cartilages and study of serial histological slices. The carapace has mixed osseous structure of endo and exoskeleton, formed by 8 pairs of costal bones associated with ribs, 7 neural bones associated with neural arches, 11 pairs of peripheral bones, 1 nuchal, 1 pygal and 1 suprapygal. This structure begins its formation in the beginning of stage 16 with the ossification of the periosteal collar of the ribs. With exception of the peripheral bones, the other ones begin their ossification during the embrionary period. In histologic investigation it was found that the costal bones and neural bones have a close relation to the endoskeleton components, originating themselves as intramembranous expansions of the periosteal collar of the ribs and neural arches, respectively. The condensation of the mesenchyme adjacent to the periosteal collar induces the formation of spikes that grow in trabeculae permeated by fibroblasts below the dermis. The nuchal bone also ossifies in an intramembranous way, but does not show direct relation to the endoskeleton. Such information confirms those related to the other Pleurodira, mainly with Podocnemis unifilis, sometimes with conspicuous variations in the chronology of the ossification events. The formation of dermal plates in the carapace of Pleurodira and Criptodira follow the same pattern.

Com objetivo de relatar a ontogenia dos elementos ósseos da carapaça em Pleurodiras, coletaram-se 62 embriões e 43 filhotes de Podocnemis expansa que foram submetidos à técnica de clareamento e coloração dos ossos e cartilagens e pelo estudo cortes histológicos seriados. A carapaça possui estrutura óssea mista de endo e exoesqueleto, sendo formada por 8 pares de ossos costais associados às costelas, 7 ossos neurais associados aos arcos vertebrais, 11 pares de ossos periféricos, 1 nucal, 1 pigal e 1 supra-pigal. Esta estrutura começa sua formação no início do estágio 16 com a ossificação do colar periostal das costelas. Com exceção dos ossos periféricos, os demais iniciam sua ossificação durante o período embrionário. A investigação histológica explicitou que os ossos costais e neurais possuem uma estreita relação com componentes do endoesqueleto, originando-se como expansões intramembranosas do colar periostal das costelas e dos arcos neurais, respectivamente. A condensação do mesenquima adjacente ao colar periostal induz a formação de espiculas que crescem em trabéculas permeadas por fibroblastos abaixo da derme. O osso nucal, também se ossifica de maneira intramembranosa mas não apresenta relação direta com o endoesqueleto. Tais informações corroboram àquelas relatadas para os demais Pleurodiras, principalmente com Podocnemis unifilis, outrora com variações conspícuas na cronologia dos eventos de ossificação. A formação das placas dérmicas da carapaça em Pleurodira e Criptodira seguem um mesmo padrão.

Comparación de la maduración ósea de vértebras cervicales utilizando los métodos de Baccetti y Lamparski en pacientes de 8 a 15 años / Comparison of bone maturation of cervical vertebrae using Baccetti and Lamparski methods in patients 8 to 15 years of age

La maduración se puede definir como un proceso gradual en el tiempo, presenta sucesivas modificaciones cualitativas en la organización anatómica y fisiológica durante la pubertad hasta el estado de madurez adulto. En el diagnóstico y tratamiento en ortodoncia es importante conocer los estadios de maduración ósea pues proporcionan información relevante que permite determinar ritmo y tiempo de maduración individual. El uso y la aplicación varían entre las técnicas y tienen un objetivo común, la clasificación de niños y adolescentes en estadios de maduración. El objetivo de este estudio fue comparar la maduración ósea de las vértebras cervicales utilizando los métodos de Baccetti y Lamparski en una población nayarita. La muestra fueron 298 radiografías laterales de cráneo de las edades de 8 a 15 años. Se compararon mediante t de Student los estadios de maduración de los grupos en el análisis CVM de Baccetti y el análisis de Lamparski; en hombres y mujeres. La población masculina de 8 y 10 años no presentaba diferencias significativas entre ambos análisis; la población femenina de 8 años y masculina de 9 años se encontraron diferencias, teniendo mayores valores el análisis CVM de Baccetti, en los demás grupos del estudio también se encontraron diferencias presentando mayores valores en el análisis Lamparski. Los estadios de maduración en los dos tipos de análisis mostraron una marcada diferencia en sus interpretaciones, siendo el análisis de Lamparski más confiable como método diagnóstico de la maduración ósea.

Maturation can be defined as a gradual process over time, presenting successive qualitative changes in the anatomical and physiological organization during puberty to the adult status maturity. In the diagnosis and treatment in orthodontics it is important to know the stages of bone maturation. This can provide us relevant information that allows us to determine pace and time of maturation individual. The use and application techniques vary between and have a common goal, the classification of children and adolescents in stages of maturation. The objective of the study was to compare bone maturation of the cervical vertebrae using the methods of Baccetti and Lamparski in a population of Nayarit. The sample consisted of 298 lateral radiographs of the skull between ages of 8­15 years old. The maturity stages of the groups of CVM and Lamparski method, in men and women, were compared using Student t test. In the masculine population between 8 and 10 years significant differences were not found between both analysis; in the 8-year-old female group and the 9-year-old males, differences were found, with the CVM Baccetti analysis having higher values. In the other study groups, differences were also found showing higher values in the Lamparski analysis. The stages of maturation in the two types of analysis showed a marked difference in their interpretations. Lamparski analysis being more reliable as a diagnostic method for bone maturation.

Assessment of skeletal and dental ages of children and adolescents with type 1 Diabetes Mellitus

The present study aimed to assess the skeletal and dental ages of type 1 diabetes mellitus (T1DM) patients. Therefore, panoramic and hand-wrist radiographs of 82 patients, aged between 5 and 15 years, were collected and divided into case and control groups. The case group consisted of 41 panoramic and 41 hand-wrist radiographs of T1DM patients, whereas the control group consisted of 41 panoramic and 41 hand-wrist radiographs of patients without T1DM. Skeletal age was assessed according to the method of Greulich and Pyle (1999), whereas dental age was assessed according to the method of Nolla (1960). Chi-square tests revealed no statistically significant differences between skeletal and dental ages between the case and control groups (p > 0.05). However, in the case group, the skeletal age of females was greater than that of age-matched males (p = 0.005). Considering that skeletal and dental growth of the case and control groups were closely related, clinical interventions involving orthodontics and dentomaxillofacial orthopedics should be equally performed both for healthy and specific patient groups, such as those with T1DM.

Skeletal maturation in individuals with Down's syndrome: Comparison between PGS curve, cervical vertebrae and bones of the hand and wrist

INTRODUCTION: This study was conducted with the aim of adapting the methods developed by Martins and Sakima to assess skeletal maturation by cervical vertebrae in the pubertal growth spurt (PGS) curve. It also aimed to test the reliability and agreement between those methods and the method of hand and wrist radiograph when compared two by two and all together. METHODS: The sample comprised 72 radiographs, with 36 lateral radiographs of the head and 36 hand-wrist radiographs of 36 subjects with Down's syndrome (DS), 13 female and 23 male, aged between 8 years and 6 months and 18 years and 7 months, with an average age of 13 years and 10 months. RESULTS AND CONCLUSIONS: Results revealed that adapting the methods developed by Martins and Sakima to assess skeletal maturation by cervical vertebrae in the curve of PGS is practical and useful in determining the stage of growth and development of individuals. The stages of maturation evaluated by cervical vertebrae and ossification centers observed in radiographs of the hand and wrist were considered reliable, with excellent level of agreement between the methods by Hassel and Farman as well as Baccetti, Franchi and McNamara Jr and Martins and Sakima. Additionally, results revealed an agreement that ranged between reasonable to good for the three methods used to assess the skeletal maturation, showing statistical significance. .

INTRODUÇÃO: esse estudo foi realizado com o propósito de adaptar os métodos para avaliação da maturação óssea por meio das vértebras cervicais na curva do Surto de Crescimento Puberal (SCP)de Martins e Sakima, assim como testar a confiabilidade e a concordância existente entre eles e o método para a radiografia de mão e punho, quando comparados 2 a 2, e entre todos, conjuntamente. MÉTODOS: a amostra constou de 72 radiografias, sendo 36 telerradiografias em norma lateral da cabeça e 36 radiografias de mão e punho, de 36 indivíduos com Síndrome de Down (SD), sendo 13 do sexo feminino e 23 do masculino, na faixa etária entre oito anos e seis meses até 18 anos e sete meses, com média de 13 anos e dez meses. CONCLUSÃO: de acordo com os resultados obtidos, concluímos que as adaptações dos métodos para a avaliação da maturação óssea por meio das vértebras cervicais na curva de SPC de Martins e Sakima resultaram em uma ferramenta prática e útil na determinação do estágio de crescimento e desenvolvimento dos indivíduos. Os estágios de maturação avaliados por meio das vértebras cervicais e os centros de ossificação observados nas radiografias de mão e punho foram considerados confiáveis, com excelente grau de concordância entre os métodos de diversos outros autores, e uma concordância de razoável a boa entre os três métodos para avaliação da maturação óssea quando comparados conjuntamente, sendo estatisticamente significativa. .

Automated assessment of developmental levels of epiphysis by support vector machine / 法医学杂志

OBJECTIVE@#To realize the automated assessment of the levels of epiphysis of distal radius and ulna by support vector machine (SVM).@*METHODS@#The X-ray films of the left wrist joints were taken from 140 teenagers aged from 11 to 19 years old as training samples. The levels of epiphysis of distal radius and ulna were divided into five developmental levels. Each level contained 28 samples. Another 35 cases were selected as independent verifying samples. SVM classification models of the five developmental levels of epiphysis of distal radius and ulna were established. The internal cross validation was made by leave one out cross validation (LOOCV), while the external validation was made by histogram of oriented gradient (HOG), and then the accuracy (PA) of testing results was calculated, respectively.@*RESULTS@#The PA of SVM, LOOCV and HOG of distal radius epiphyseal level were 100%, 78.6%, and 82.8%, respectively; whereas the PA of SVM, LOOCV and HOG of distal ulna epiphyseal level were 100.0%, 80.0% and 88.6%, respectively.@*CONCLUSION@#The SVM-based automatic models of the growth stage of distal ra- dius and ulna appear to have certain feasibility, and may provide a foundation for software development of bone age assessment by forensic medicine.

Maduración dentaria en jovenes venezolanos estimada mediante el método de demirjian y colaboradores / Dental maturation in venezuelan young estimated though demirjian et al method

El objetivo de este trabajo fue estudiar la maduración dentaria en jóvenes venezolanos estimada mediante el método de Demirjian y cols. Se analizaron 284 radiografías panorámicas de pacientes de ambos sexos con edades cronológicas entre 8- 20 años. Se estudio la maduración dentaria de los 7 dientes inferiores izquierdos de acuerdo a los estadios del método de Demirjian y cols. y se calculó la edad dentaria. Se obtuvieron la media y la desviación estándar de la edad cronológica (EC) y la ED, la media de la EC a la cual se observaron los diferentes estadios de maduración y diferencias de medias entre la EC y la ED calculada. Al comparar las medias de las edades cronológicas en las que se observaron los estadios de maduración dentaria, las hembras tuvieron un desarrollo más avanzado que los varones. Se evidencio que el 100% de madurez dentaria, comienza a alcanzase alrededor de lo 13-14 años en la muestra estudiada. Contrastando la media de la EC con la ED, pudo verificarse que en ambos sexos, existe una consistente subestimación de la edad a partir de los 16 años, por ello en una submuestra de los grupos 8-16 se obtuvieron las diferencias de media entre la EC y ED, y se encontró una sobrestimación de la edad, estadísticamente significativa (-0,66 ±1,14 varones; -0,40± 1,38 hembras). Los datos del presente trabajo podrían ser utilizados como referencia de la maduración dentaria de los individuos de la muestra...

The aim of the present investigation was to study the dentaria maturation of Venezuelan young estimated though Demirjian´s et al. method. Two hundred and eighty four dentaria panoramic radiographs from patients of both sexes, with chronological ages between 8-20 years, were analyzed. Dentaria maturation of the 7 left lower teeth was calculated, according to the stages proposed by Demirjian et al. and dentaria age was calculated (DA) following the method of the author. Mean values and standard deviation of the chronological age (CA) and DA, by age group, mean of the CA to which different stages of maturation were observed and mean differences between the CA and the DA, were calculated. When comparing the mean chronological ages witch the dentaria maturation stages were observed; females had more advanced development than males. It was noticed that 100% of dentaria maturity, was reached out around 13-14 years in the studied sample. Contrasting mean CA with DA, it could be confirmed that in both sexes, there is a consistent underestimation of age from 16 years, so in a subsample of 8-16 groups mean differences between the EC and ED were obtained, and found an statistically significant overestimation of age (males -0.66 ± 1.14, females -0.40 ± 1.38). The data presented here could be used as a reference for dentaria maturation of the individuals in the sample...

Anatomical evaluation of the cervical vertebrae of Wistar rats by means of digital radiographs and its correlation with the maturation stages of human cervical vertebrae

INTRODUCTION: Biological age is an important parameter for growth and development assessment. It can be evaluated through the observation of radiographic changes in skeletal maturation of cervical vertebrae. OBJECTIVE: This study aims to: a) verify if there is correlation between growth curve and the stages of bone age of animals used in laboratories, by evaluating radiographs of the cervical vertebrae; b) correlate these stages with their correspondents in humans. METHODS: 35 Wistar rats were evaluated for a period of 160 days, starting at day 22nd (weaning), with cross sections for periodic weighing, length measurement and digital radiography. Radiographs of the cervical vertebrae (C2 and C3) were measured by means of a computer program (Radio IMP). Data were submitted to statistical analysis (ANOVA) and Pearson correlation. RESULTS: Growth spurt was characterized by fast increasing in weight and length. Through ANOVA, differences were observed in the cervical measurements between days 22, 97, 127, 157, 187 and 217 (p <0.001). A high correlation was found between increasing in body length and weight, as well as in cervical vertebrae height (r = 0.86). Increments in concavities of vertebrae were also observed, similar to humans. CONCLUSIONS: There is correlation between body growth and maturation of cervical vertebrae in rats. Despite the continuous development of concavities, it was not possible to clearly identify the 5/6 stages as in studies of cervical vertebrae maturation in humans.

INTRODUÇÃO: a idade biológica é um parâmetro importante na avaliação do crescimento e desenvolvimento, podendo ser avaliada por meio da observação de alterações na maturação óssea das vértebras. OBJETIVO: o presente estudo visa descrever e relacionar a curva de crescimento de ratos utilizados em pesquisas laboratoriais com os estágios de idade óssea, avaliados por radiografias de vértebras cervicais, e correlacionar esses estágios com estudos correspondentes em humanos. MÉTODOS: foram avaliados 35 ratos Wistar em um período de 160 dias, iniciando no 22º dia de vida (desmame), com cortes transversais periódicos para pesagem, medição do comprimento e radiografias digitais. As radiografias das vértebras cervicais (C2 e C3) foram mensuradas por meio de um programa de computador (Radio IMP). Os dados foram submetidos à análise estatística de variância (ANOVA). RESULTADOS: o surto de crescimento caracterizou-se por aumento rápido de peso e comprimento, seguido por um período de crescimento lento e de estabilidade. Uma alta correlação (r = 0,86) foi verificada entre o aumento de peso e o comprimento do corpo, bem como o comprimento das vértebras cervicais. Incrementos nas concavidades das vértebras dos ratos foram observados, semelhantemente aos resultados obtidos em estudos em humanos. CONCLUSÕES: existe correlação entre o crescimento corporal de ratos e a maturação das vértebras cervicais. Apesar da detecção de desenvolvimento contínuo de concavidades das vértebras, não foi possível identificar claramente os 5 ou 6 estágios de maturação óssea descritos em seres humanos.

Bone development trend in the knee joint of Tibetan teenagers in Aba Prefecture of Sichuan Province / 法医学杂志

OBJECTIVE@#To discuss bone development trend in the knee joint of Tibetan teenagers in Sichuan province and to effectively update the database for estimating the living age of Tibetan teenagers in terms of bone age of the knee joint.@*METHODS@#Radiographs including epiphysis of distal femur, proximal tibia and proximal fibula were taken from 483 Tibetan male and female teenagers aged from 14 to 19 years old in Aba prefecture of Sichuan province in order to observe epiphyseal growth situation. The descriptive data of the epiphyseal closure ages of these teenagers' knee joints were statistically analyzed by SPSS 16.0 software.@*RESULTS@#The distal femur epiphyseal closure occurred earliest, while the proximal fibula epiphyseal closure occurred latest. The epiphyseal growth of knee joints of females occurred about one year earlier than that of males.@*CONCLUSION@#The forensic information and data related to Tibetan teenagers' bone age identification should be updated regularly. These results provide potential value for the practice of forensic medicine, anthropology and clinical medicine.

Skeletal age estimation by pelvic X-ray of Han teenagers in Sichuan / 法医学杂志

OBJECTIVE@#To estimate the chronological age of Han teenagers in Sichuan by the epiphyses development characteristics of iliac crest and ischial tuberosity in X-ray digital images.@*METHODS@#According to TW2 classification principle, combining with the age range of our subjects and epiphyses development regularity, the degree of epiphyses development of iliac crest and ischial tuberosity had been divided into 8 grades (0-7) and 7 grades (0-6), respectively. Based on the degrees, the pelvic X-rays digital images of 691 samples of 16-20 aged teenagers were read and statistically analyzed by SPSS 19.0 software. The multiple linear regression equation was established by skeletal age (Y), development degree of iliac crest epiphyses (X1) and ischial tuberosity epiphyses (X2).@*RESULTS@#There were no statistical differences between two sides of epiphyses development of iliac crest and ischial tuberosity (P>0.05). There were no statistical difference between genders (P>0.05). The re-substitution method of the samples showed that the accuracy of equation as Y=15.269+0.444X1+0.236 X2 was high. The result of the re-substitution method showed a high accuracy of the equation.@*CONCLUSION@#The multiple linear regression equation could be used to identify the skeletal age for providing the scientific basis to identify the 18-year-old Han population in Sichuan.

Histomorphometric analysis of the temporal bone after change of direction of force vector of mandible: an experimental study in rabbits

OBJECTIVES: The present study aimed at performing a histological evaluation of the response of temporal bone tissue to a change of direction of the force vector of the mandible in relation to the base of the skull. MATERIAL AND METHODS: Adult rabbits were assigned into four groups with two control and four experimental animals in each group. experimental animals underwent surgery, which resulted in a change of direction of the force vector on the right temporomandibular joint. Samples were collected after 15, 30, 60 and 90 days for histological analysis. RESULTS: In the two-way analysis of variance, the effect of group and time was statistically significant (p<0.001). Additionally, a statistically significant interaction between group and time was observed (p<0.001). Control animals showed normal growth and development of the temporal region. In the experimental group, the change in direction of the force vector of the mandible induced significant changes in the temporal bone, with a bone modeling process, which suggests growth of this cranial structure. CONCLUSIONS: The methodology used in this experiment allows us to conclude that the change in direction of the force vector of the mandible in relation to the skull base induces remodeling and modeling processes in the temporal bone. The resumption of normal oral functions after bone healing of the mandibular fracture appears to increase cell activation in the remodeling and modeling of the temporal bone structure. The observation of areas of temporal bone modeling shows the relevance of further investigation on the correlation between the joint structures and craniofacial growth and development.

Skeletal maturation of the cervical vertebrae: association with various types of malocclusion

The identification of the skeletal maturation stage of the cervical vertebrae has proven an important reference for orthodontic diagnosis. The aim of the present study was to determine the association between the skeletal maturation stage of the cervical vertebrae and types of malocclusion according to the age and gender of participants. A total of 361 individuals (168 males and 193 females) between 8 and 14 years of age were selected from a convenience sample. Malocclusions were diagnosed through study models using the Angle classification. Maturation stages of the cervical vertebrae were determined using the method proposed by Hassel and Farman. Statistical analysis involved the chi-square test (p £ 0.05) and multiple logistic regression (forward stepwise procedure). Significant differences were observed between the stage of skeletal maturation of the cervical vertebrae and gender at ages 11, 12 and 14 years. Males with Class II malocclusion were twice as likely to be in Stage 1 or 2 of cervical vertebra maturation than individuals with Class I malocclusion (OR = 2.1 [CI 95%, 1.33-3.18]). There were no differences between individuals with Class I and Class III malocclusions. The association between skeletal maturation of the cervical vertebrae and type of malocclusion was significant, suggesting a skeletal component in the determination of Class II malocclusions.

Long-term trend of bone development in the contemporary teenagers of Chinese Han nationality / 法医学杂志

OBJECTIVE@#To further improve the accuracy of bone age identification using the time of secondary ossification center appearance and epiphyseal fusion of 7 joints to estimate the age of living individuals.@*METHODS@#DR films were taken from 7 parts including sternal end of clavical and the left side of shoulder, elbow, carpal, hip, knee and ankle joints of 1 709 individuals who came from eastern China, central China and southern China, whose ages were between 11.0 and 20.0 years. From those 7 joints 24 osteal loci were selected as bone age indexes, which could better reflect age growth of teenagers. The characteristics of secondary ossification center appearance and epiphyseal fusion were observed, and the mean and age range of secondary ossification center appearance and epiphyseal fusion were calculated.@*RESULTS@#The fusion time of the 24 epiphyses were advanced at different degrees, the most obvious epiphyses the sternal end of clavicle, scapular acromial end, distal end of the radius, distal end of the ulna, iliac crest, ischial tuberosity, the upper and lower end of tibia and fibula. The appearance time of sternal end of clavicle, scapular acromial end, iliac crest and ischial tuberosity epiphyses were all found to be after the age of 12, and the female's age, approximately 1 year ahead of schedule in comparison with the male's.@*CONCLUSION@#The relevant forensic information and data for bone age identification should be updated every 10-15 years so as to provide accurate and objective evidence for court testimony, conviction and sentencing.

Analysis of variation of Han male adolescent bone development in Hainan, Henan and Zhejiang provinces / 法医学杂志

OBJECTIVE@#To study the difference of bone development of the Han male adolescents in Hainan, Henan and Zhejiang provinces.@*METHODS@#All radiographs including sternal end of clavicle, pelvis and six main bone joints taken from 877 Han male adolescents aged between 12.00 and 20.00 in Hainan, Henan and Zhejiang provinces were reviewed. Twenty-four indices of skeletal development were analyzed based on "The Grading Standards" of skeletal growth of teenagers and then the bone age were calculated using mathematical model functions. The ratios of the bone age and the chronological age were then analyzed by statistical software.@*RESULTS@#The development of Hainan male adolescents' skeleton were about 1.09 years and 1.26 years earlier than that in Henan and Zhejiang at the age group of 12.00-12.99 years. The development of Hainan male adolescents' skeleton were about 0.70 years and 1.38 years earlier than that in Henan and Zhejiang at the age group of 13.00-13.99 years, while the development of Henan male adolescents' skeleton were about 0.68 years earlier than that in Zhejiang in this age group. The development of Hainan male adolescents' skeleton were about 0.79 years later than that in Henan at the age group of 18.00-18.99 years. The development of Hainan male adolescents' skeleton were about 0.70 years and 0.95 years later than that in Henan and Zhejiang at the age group of 19.00-20.00 years.@*CONCLUSION@#There are significant differences in the skeleton development of Han male adolescents between the provinces of Hainan, Henan and Zhejiang. These results provide potential value for the practice of forensic medicine, anthropology and clinical medicine.