Age Prediction Using Pixel Value Sum from Radiographic Proximal Femur in a Thai Population / Predicción de la Edad Utilizando la Suma de Valores de Pixeles del Fémur Proximal Radiográfico en una Población Tailandesa

SUMMARY: The present study aimed to investigate the utility of the proximal femur in the forensic age estimation by assessing changes in bone densities through radiographs. Using Otsu's threshold, bone density was quantified by counting all white pixel values within selected regions of interest, which include femoral head (FH), femoral neck (FN), Ward's triangle (WT), and greater trochanter (GT) from 354 left femora of Northern Thai descent. The pixel width of medullary cavity (MC) was also estimated. Furthermore, the study evaluated the performance of linear regression (LR) models for age estimation from radiographic images of proximal femora. Negative correlations were observed between FH, FN, WT, and GT pixel intensity with the age-at-death of the samples, with females exhibiting stronger correlations than males. Moreover, a positive correlation was found between age and MC width in female samples, while male MC widths did not show any relationship with increasing age. The results showed a slight difference between the LR model applied to both sexes, which integrated all variables, and the alternative configuration that only utilized relevant attributes. Both models exhibited similar performance, with a narrow range of root mean square error (RMSE) values, ranging from 12.67 to 12.71 years, and a correlation coefficient range of 0.51 to 0.52. For females, the LR model with FN and WT as selected attributes (RMSE = 11.85 years, correlation coefficient = 0.65) performed decently, while for males, the LR model with all variables showed RMSE of 12.52 years and correlation coefficient of 0.46. This study showcased the potential application of pixel intensity in predicting age.

El presente estudio tuvo como objetivo investigar la utilidad del fémur proximal en la estimación forense de la edad mediante la evaluación de cambios en las densidades óseas a través de radiografías. Utilizando el umbral de Otsu, la densidad ósea se cuantificó contando todos los valores de pixeles blancos dentro de regiones de interés seleccionadas, que incluyen la cabeza femoral (CF), el cuello femoral (CF), el triángulo de Ward (WT) y el trocánter mayor (TM) de 354 fémures izquierdos de ascendencia del norte de Tailandia. También se estimó el ancho de pixeles de la cavidad medular (CM). Además, el estudio evaluó el rendimiento de modelos de regresión lineal (RL) para la estimación de la edad a partir de imágenes radiográficas de fémur proximal. Se observaron correlaciones negativas entre la intensidad de los pixeles CF, CF, WT y TM con la edad de muerte, y las mujeres exhibieron correlaciones más fuertes que los hombres. Además, se encontró una correlación positiva entre la edad y el ancho del CM en muestras de mujeres, mientras que el ancho del CM del hombre no mostró ninguna relación con el aumento de la edad. Los resultados mostraron una ligera diferencia entre el modelo RL aplicado a ambos sexos, que integraba todas las variables, y la configuración alternativa que sólo utilizaba atributos relevantes. Ambos modelos mostraron un rendimiento similar, con un rango estrecho de valores del error cuadrático medio (RMSE), que oscilaba entre 12,67 y 12,71 años, y un rango de coeficiente de correlación de 0,51 a 0,52. Para las mujeres, el modelo RL con CF y WT como atributos seleccionados (RMSE = 11,85 años, coeficiente de correlación = 0,65) tuvo un desempeño satisfactorio, mientras que para los hombres, el modelo RL con todas las variables mostró un RMSE de 12,52 años y un coeficiente de correlación de 0,46. Este estudio mostró la posible aplicación de la intensidad de los pixeles en la predicción de la edad.

Biological Identification of Skulls in Indonesian and Thai Populations: Ancestry Estimation, Sex Determination, Stature Estimation, and Age Estimation / Identificación Biológica de Cráneos en Poblaciones de Indonesia y Tailandia: Estimación de Ascendencia, Determinación del Sexo, Estimación de Estatura y Estimación de Edad

SUMMARY: This review article will present an overview of biological profiles in forensic utilities. The biological profile of the skull in the existing literature can help to identify humans, especially if the condition of the victim found is a result of mutilation or a bomb explosion. When it comes to the precision of identifying skeletal remains, the human skull is frequently cited as being first in the estimation of age and ancestry and second in terms of sex and stature. It can be an alternative to assessing the following biological parameters: sex, age, stature, and ancestry. The implementation of biological profiles in the identification process is very important considering that some cases require the assistance of forensic anthropology. This review article shows the importance of the value of skulls. The method that can be applied is craniometry which can be used to determine sex, age, stature, and estimated ancestry. Different results will occur depending on the completeness of the skull. Therefore, estimation formulas have different accurate results. Discriminant function analysis has been performed on various measurement sets and its discriminant power has been validated by many researchers. Geometric morphometric analysis has become the main tool for shape analysis and many attempts have been made to use it in analyzing skulls. Several methods supported by technology have also been developed. It is hoped that the review article will show significant differences in results between studies in Thailand and Indonesia, even though they are in the same racial group.

Este artículo presenta una descripción general de los perfiles biológicos en las utilidades forenses. El perfil biológico del cráneo en la literatura existente puede ayudar a identificar a los humanos, especialmente si la condición en la que se encuentra la víctima es el resultado de una mutilación o la explosión de una bomba. Cuando se trata de la precisión en la identificación de restos óseos, el cráneo humano se cita con frecuencia como el primero en la estimación de edad y ascendencia y el segundo en términos de sexo y estatura. Puede ser una alternativa para evaluar los siguientes parámetros biológicos: sexo, edad, estatura y ascendencia. La implementación de perfiles biológicos en el proceso de identificación es importante considerando que algunos casos requieren la asistencia de la antropología forense. Este artículo de revisión muestra la importancia del valor de las cnezas óseas. El método que se puede aplicar es la craneometría para determinar el sexo, la edad, la estatura y la ascendencia estimada. Se pueden obtener diferentes resultados dependiendo de la integridad del cráneo. Por lo tanto, las fórmulas de estimación tienen resultados precisos diferentes. Se ha realizado un análisis de función discriminante en varios conjuntos de medidas y muchos investigadores han validado su poder discriminante. El análisis a través de la morfometría geométrica se ha convertido en la principal herramienta para el análisis de formas y se ha utilizado frecuentemente en el análisis de cráneos. También se han desarrollado varios métodos apoyados en la tecnología. Se espera que este trabajo muestre diferencias significativas en los resultados entre los estudios realizados en Tailandia e Indonesia, aunque pertenezcan al mismo grupo racial.

Validity of the Maturation Stage Method in the Individual Assessment of Midpalatal Suture Ossification Before Maxillary Expansion: A Systematic Review / Validez del Método de la Etapa de Maduración en la Evaluación Individual de la Osificación de la Sutura Palatina Mediana Previo a la Expansión Maxilar: Una Revisión Sistemática

In 2013, midpalatal suture maturation stage assessment was proposed for the evaluation of patients before performing maxillary expansion. In this study, we aimed to analyze the association between the midpalatal suture maturation stages assessed by CBCT, according to the method described by Angelieri et al., and other objective methods used to assess skeletal maturation or bone fusion. A computerized database search was conducted using PubMed, Cochrane Library, SciELO, LILACS, Web of Science, and Scopus, without language restriction. Unpublished literature was searched on ClinicalTrials.gov, the National Research Register, and Pro-Quest Dissertation Abstracts and Thesis database. Authors were contacted when necessary, and reference lists of the included studies were screened. Search terms included midpalatal suture, maturation, correlation, diagnostic performance, classification, evaluation, assessment, and relationship. Quality assessment was performed using the Observational Cohort and Cross-Sectional Studies tool developed by the National Heart, Lung, and Blood Institute. Eleven studies met the inclusion criteria. Of all the studies included, 81.9% had fair qualit y and 18.1% good quality, respectively. Eight out of eleven studies assessed the correlation between the midpalatal suture maturation method and the skeletal maturity evaluated by CVM method (Spearman's correlation coefficient: 0.244-0.908). Two out of eleven studies evaluated the correlation between midpalatal suture maturation method and the skeletal maturity assessed by HWM method (Spearman's correlation coefficient: 0.904-0.905) Even though midpalatal suture maturation stage assessment needs an exhaustive training and calibration process, it is a valid method to evaluate skeletal maturation or bone fusion. From a clinical perspective, for patients at CS4, CS5 and CS6, an assessment of the midpalatal suture on CBCT is indicated. A similar assessment should be done in patients at SMI 7-9.

En 2013, se propuso un nuevo método para la evaluación del estadio de maduración de la sutura palatina mediana para la evaluación de los pacientes antes de realizar la expansión maxilar. En este estudio, nuestro objetivo fue analizar la asociación entre las etapas de maduración de la sutura palatina mediana evaluada en CBCT, según el método descrito por Angelieri et al., y otros métodos objetivos utilizados para evaluar la maduración esquelética o la fusión ósea. Se realizó una búsqueda en las bases de datos PubMed, Cochrane Library, SciELO, LILACS, Web of Science y Scopus, sin restricción de idioma. Se buscó literatura no publicada en ClinicalTrials.gov, el Registro Nacional de Investigación y la base de datos Pro-Quest Dissertation Abstracts and Thesis. Se estableció contacto con los autores cuando fue necesario y se revisaron las listas de referencias de los estudios incluidos. Los términos de búsqueda incluyeron sutura palatina mediana, maduración, correlación, rendimiento diagnóstico, clasificación, evaluación, valoración y relación. La evaluación de la calidad se realizó mediante la herramienta de Estudios transversales y de cohortes observacionales desarrollada por el Instituto Nacional del Corazón, los Pulmones y la Sangre. Once estudios cumplieron con los criterios de inclusión. Del total de estudios incluidos, el 81.9% tuvo calidad regular y el 18.1% calidad buena, respectivamente. Ocho de once estudios evaluaron la correlación entre el método de maduración de la sutura palatina mediana y la madurez esquelética evaluada por el método CVM (coeficiente de correlación de Spearman: 0.244-0.908). Dos de once estudios evaluaron la correlación entre el método de maduración de la sutura palatina mediana y la madurez esquelética evaluada por el método HWM (coeficiente de correlación de Spearman: 0.904-0.905). Aunque la evaluación del estado de maduración de la sutura palatina mediana necesita un proceso exhaustivo de entrenamiento y calibración, es un método válido para evaluar la maduración esquelética o la fusión ósea. Desde una perspectiva clínica, para pacientes en CS4, CS5 y CS6, está indicada una evaluación de la sutura palatina mediana en CBCT. Se debe realizar una evaluación similar en pacientes con SMI 7-9.

Research Progress of Age Estimation in the Living by Knee Joint MRI / 法医学杂志

Bone development shows certain regularity with age. The regularity can be used to infer age and serve many fields such as justice, medicine, archaeology, etc. As a non-invasive evaluation method of the epiphyseal development stage, MRI is widely used in living age estimation. In recent years, the rapid development of machine learning has significantly improved the effectiveness and reliability of living age estimation, which is one of the main development directions of current research. This paper summarizes the analysis methods of age estimation by knee joint MRI, introduces the current research trends, and future application trend.

Estimation of the predictive effect of body mass index-percentile on skeletal maturation in a Nigerian population

To determine the predicting the effect of BMI-index percentile on the skeletal maturation of Nigerian children. Design: A prospective cross-sectional study. Setting: This study was conducted in a tertiary health care facility in North-Central Nigeria. Participants: Children between the ages of 5-17 years consisting of 44 males and 30 females that presented in the Child Dental clinic over a period of eight months were recruited for the study. Main outcome measured: Skeletal maturation was assessed using the middle phalanx of the third finger (MP3) while the standard WHO growth chart specific for age (2-20 years) and gender was used for grading BMI-percentile. The unpaired t-test was used to compare mean chronological age of the stages of MP3 according to gender. Multinomial logistic regression used to determine the predictive effect of age, gender and BMI percentile on pubertal growth spurt. Results: The BMI-percentile had weak correlation with the pubertal growth spurt (r=0.089, p=0.448). Gender (p=0.004) and chronological age had significant (p<0.001) predictive effect on the skeletal maturation. A one-percentile increase in the BMI-percentile decreases the likelihood of healthy children to be in the peak-pubertal by 1.504 when compared to obese children (p=0.305). Conclusions: This study showed that BMI-percentile is a weak predictor of skeletal maturation. However, obese children had a tendency towards advanced skeletal maturation than healthy participants. It is therefore suggested that orthodontists should consider early implementation of jaw modification treatments among obese children.

Estimation of the predictive effect of body mass index-percentile on skeletal maturation in a Nigerian population

Aim: To determine the predicting effect of BMI-index percentile on the skeletal maturation of Nigerian children. Materials and Methods: A cross-sectional descriptive study. This study was conducted in a tertiary health care facility in North-Central Nigeria. Participants were children between the ages of 5-17 years consisting of 44 males and 30 females who presented in the child dental clinic over a period of eight months were recruited for the study. Skeletal maturation was assessed using the middle phalanx of the third finger (MP3), while the standard WHO growth chart specific for age (2-20 years) and sex was used for grading BMI-percentile. The unpaired t-test was used to compare mean chronological age of the various stages of MP3 according to sex. Multinomial logistic regression was used to determine the predictive effect of age, sex, and BMI percentile on pubertal growth spurt. Results: The BMI- percentile did not show a significant correlation with the pubertal growth spurt (r=0.089, p=0.448). Sex (p=0.004) and chronological age had significant (p<0.001) predictive effect on the skeletal maturation, unlike the BMI-percentile. A onepercentile increase in the BMI- percentile decreases the likelihood of healthy children to be in the peak-pubertal by 1.504 when compared to obese children (p=0.305. Conclusion: This study showed that BMI-percentile is a weak predictor of skeletal maturation. However, obese children had a tendency towards advanced skeletal maturation than healthy participants. It is therefore suggested that orthodontists should consider early implementation of jaw modification treatments among obese children.

Determination of age and sex using bimastoid diameter: a cone beam computed tomography Study / Deteminación de la edad y el sexo mediante el diámetro bimastoide: un estudio en tomografía computarizada de haz cónico (CBCT)

Abstract This study aimed to investigate the possibility of age and sex determination using bimastoid diameter with cone-beam computed tomography (CBCT). This retrospective study investigated 100 female and 100 male patients aged 18-83 years (mean age: 45.55±16.28 years). To measure bimastoid diameter, the appropriate image was chosen from sagittal, coronal, and axial images of CBCT in which the measurement points could be best detected. The distance between the points of the mastoid process was measured using three-dimensional coronal reconstruction. The mean bimastoid breadth was 106.12±6.22mm. The bimastoid diameter in male cases was higher than that in female cases (110.69±4.53mm vs. 101.65±4.00mm). There was no significant difference in bimastoid breadth with advancing age. For sex determination, morphometric measurements of bimastoid diameter ensured a high rate of dimorphism in the Turkish subpopulation. CBCT morphometric analysis may be reliable and convenient for evaluating sex and may be recommended to compare population data.

Resumen Este estudio tuvo como objetivo investigar la posibilidad de determinar la edad y el sexo utilizando el diámetro bimastoideo con tomografía computarizada de haz cónico (CBCT). Este estudio retrospectivo investigó a 100 mujeres y 100 hombres de entre 18 y 83 años (edad media: 45,55±16,28 años). Para medir el diámetro bimastoideo, se eligió la imagen adecuada de las imágenes sagital, coronal y axial de CBCT en las que los puntos de medición se podían detectar mejor. La distancia entre los puntos del proceso mastoideo se midió mediante reconstrucción coronal tridimensional. La amplitud media del bimastoide fue de 106,12± 6,22mm. El diámetro del bimastoide en los casos masculinos fue mayor que en los casos femeninos (110,69±4,53 mm frente a 101,65±4,00mm). No hubo diferencias significativas en la amplitud del bimastoide con la edad. Para la determinación del sexo, las mediciones morfométricas del diámetro bimastoide aseguraron una alta tasa de dimorfismo en la subpoblación turca. El análisis morfométrico CBCT puede ser confiable y conveniente para evaluar el sexo y puede recomendarse para comparar datos poblacionales.

Ethical aspects of age estimation for forensic purposes in Saudi Arabia / Aspectos éticos de la estimación de la edad para propósitos forenses en Arabia Saudita / Aspectos éticos da estimativa de idade para propósitos forenses na Arábia Saudita

Abstract: In forensic and legal contexts, an assessment of skeletal maturation is required to predict the chronological age in certain circumstances in which the chronological age is undocumented or unable to be proven. Carrying such medical examinations will always pose an ethical concern, especially in cases of assessing sexual maturity as well as examinations involving ionizing radiation. The cultural and religious barriers are also discussed concerning the ethical standards set in Saudi Arabia. Several ethical issues concerning age estimation examinations including issues related to consent forms, privacy, and radiation hazards have been documented. While ethical issues regarding radiation hazards are more likely to be overcome by introducing other imaging modalities without radiation hazards, ethics related to consent forms and privacy are still to be improved.

Resumen: En contextos forenses y legales, se requiere la evaluación de la maduración del esqueleto para predecir la edad cronológica en ciertas circunstancias en que la edad cronológica no está documentada o no es posible de probar. Realizar tales exámenes médicos siempre significa una preocupación ética, especialmente en casos de evaluación de madurez sexual así como en exámenes que involucran radiaciones ionizantes. Se discuten también las barreras culturales y religiosas relacionadas con el contexto de estándares éticos en Arabia Saudita. Entre los varios temas éticos relacionados con la estimación de la edad, se documentan temas relacionados con los formularios de consentimiento, privacidad y riesgos de radiación. Mientras que los temas éticos relacionados con riesgos de radiación pueden ser resueltos al introducir otras modalidades de examen sin radiación, los problemas éticos relacionados con los formularios de consentimiento y privacidad todavía necesitan mejorarse.

Resumo: Em contextos forenses e legais, uma avaliação de maturação esquelética é requerida para predizer a idade cronológica em certas circunstâncias nas quais a idade cronológica não é documentada ou impossível de ser provada. Conduzir tais exames médicos sempre irá suscitar uma preocupação ética, especialmente em casos para avaliar maturidade sexual bem como exames envolvendo radiação ionizante. As barreiras culturais e religiosas também são discutidas no que diz respeito a padrões éticos estabelecidos na Arábia Saudita. Diversos aspectos éticos concernentes a exames de estimativa de idade incluindo aspectos relacionados a formulários de consentimento, privacidade e risco de radiação foram documentados. Ao passo que aspectos éticos que dizem respeito a risco de radiação serem mais provavelmente superáveis pela introdução de outras modalidades de exames de imagem sem risco de radiação, a ética relacionada a formulários de consentimento e privacidade ainda estão por serem melhorados.

Comparison of Three Methods for Skeleton Age Estimation / 法医学杂志

OBJECTIVES@#To find the appropriate method for age estimation for different ages and sexes.@*METHODS@#The costal cartilage, sternum and pubic symphysis of 91 unknowns from 2000 to 2020 from the Forensic Department of the Criminal Investigation Team of Shanghai Public Security Bureau were collected. Costal cartilage, sternal and pubic symphysis inferences were used to estimate the age, and the consistency between the estimated results and the actual physiological age of the unknowns was tested. The accuracy of age estimation of different samples was compared, and the relationship between accuracy and age and sex was analyzed.@*RESULTS@#Using the costal cartilage method, the inference errors of males, females and the whole population under 40 years old were (0.608±2.298) years, (0.429±1.867) years and (0.493±2.040) years, while those over 40 years old were (-1.707±3.770) years, (-3.286±4.078) years and (-2.625±4.029) years. The differences between different age groups in these three populations were statistically significant (P<0.05). Using the sternum method, the inference errors of males and females under the age of 40 were (0.921±3.019) years and (0.452±1.451) years, while those over the age of 40 were (-5.903±5.088) years and (-1.429±2.227) years. The differences between different age groups in males and females were statistically significant (P<0.05). Using the pubic symphysis method, the inference errors of males and females under 40 years old were (-0.204±1.876) years and (0.238±2.477) years, while those over 40 years old were (1.500±2.156) years and (-2.643±4.270) years. The differences between different age groups in males and females were statistically significant (P<0.05). Using the sternum method and pubic symphysis method for age estimation of over 40 years old, the difference between different sexes was statistically significant (P<0.05).@*CONCLUSIONS@#All three methods of age estimation are stable and effective and more accurate for people under 40 years old. For age estimation of unknowns over 40 years old, the pubic symphysis method is preferred in males and the sternum method is preferred in females.

Skeletal maturation pattern among Down Syndrome individuals in Benin, City. Nigeria

Background: The assessment of skeletal maturity is important in the timing of orthodontic treatment especially in the modification of dento-facial growth. The use of cervical vertebrae as a method of assessment of skeletal maturity has rarely been used among Down Syndrome. Objective: To assess skeletal maturity among individuals with Down Syndrome using the cervical vertebrae maturation stages. Methods: The study was conducted among 21 Down Syndrome with mean ages of 11.70  1.83 years (males) and 13.64  1.75 years (female); and 21 control individuals with mean ages of 12.00  2.00 years (male), and 13.50  1.90 years (female). The independent t-test and chi-square test were used to determine significant differences among the continuous (age) and categorical variables (cervical vertebrae maturation stages) respectively when matched with gender and chronological age. Fischer exact test was used when an expected frequency presentation was <5. A p-value of < 0.05 was set as statistically significant. Results: Down Syndrome males had delayed maturation at 11 years but accelerated at 12 with early attainment of maturity at 15 years. Down Syndrome female had a delay tendency in skeletal maturation from 11­15 years of age. Overall, Down Syndrome had a 1.242 probability of either having a delay or advancement in skeletal maturation which was not statistically significant. Conclusively, the skeletal maturation pattern between Down syndrome patients and normal individuals was not statistically different. Conclusion: The average timing for commencement of orthodontic treatment especially growth modification for normal individuals can be applied for individuals with Down Syndrome as this present study did not show any statistically significant difference in their overall skeletal maturation.

Research Progress on Computer-Aided Skeleton-Based Individual Identification in Forensic Radiology / 法医学杂志

Individual identification based on imaging data of the skeleton of a corpse is a key technique for forensic identification. To reduce the influence of artificial factors, computer-aided semi-automatic or automatic individual identification has become one of the research directions of skeleton-based individual identification in forensic radiology. Therefore, this paper reviews and summarizes literatures related to estimation of anthropological information such as, age and sex by computer-aided forensic radiology bone characteristics and individual identification based on bone imaging characteristics, in order to provide reference on skeleton-based individual identification in forensic radiology.

Pubertal growth spurt peak in angle class I and II Malocclusions using cervical vertebrae maturation analysis in Deutero-Malay children

Background@#The incidence rate of Angle Class I and Class II malocclusions in mixed dentition is higher than Class III. In orthodontic interceptive treatment, it is necessary to identify pubertal growth spurt peak individually because the best growth modification could be obtained during this period. One of the methods in assessing the pubertal growth spurt peak is cervical vertebrae maturation (CVM), which is done using a lateral cephalometric radiograph. CVM evaluates potential growth and skeletal maturity by assessing cervical vertebrae anatomy. Identifying the duration of growth spurt peak on both malocclusion classes is the most pivotal aspect of optimizing remodeling and correction of children’s malocclusion. @*Objective@#Distinguishing the duration of pubertal growth spurt peak of children with Angle Class I and II malocclusions based on CVM analysis in Deutero-Malay children so that it can be used in determining optimal orthodontic treatment plan and timing in children with Class I and Angle II malocclusion for Deutero-Malay children. @*Methods@#Analytical observational with cross-sectional approach was applied using lateral cephalometric radiographic images from patients’ medical records attending or had attended orthodontic treatment in the Pediatric Dentistry Clinic, Airlangga University Dental Hospital, Surabaya, Indonesia, in 2014-2019 that met the inclusion criteria and were analyzed with Baccetti’s method of CVM analysis. This study involved 66 conventional lateral cephalometric photographs that were selected using total sampling. The data were analyzed using Independent T-Test and Mann Whitney U Test. @*Result@#The duration of pubertal growth spurt peak in Angle Class I and II malocclusions was 11 and 7 months, respectively. The age of onset for Class I with CS3 was 9 years and 5 months, while for Angle Class II malocclusion starts entering the stage at 10 years 3 months of age, while for CS4 skeletal maturity we found that the age of onset for subjects with Angle Class I and II were 11 years 2 months and 12 years 4 months, respectively. The average duration of the pubertal growth spurt peak in female and male patients was 11.3 months and 18.2 months, respectively. All of these results were statistically significant (p ≤ 0.001) and representative of the population, in this case, Deutero-Malays. @*Conclusion@#Four-month differences in the duration of pubertal growth spurt peak of children with Angle Class I and II were found. This may lead to a shorter treatment duration of 4 months in children with Angle Class II malocclusion when compared to children with Angle Class I malocclusion. Angle Class II malocclusion exhibit shorter pubertal growth spurt peak duration, which may account for the difference in mandibular growth on the two malocclusion classes.

Tooth Coronal Index: A Novel Tool For Age Estimation on Cone-Beam Computed Tomography

ABSTRACT Objective: To evaluate dental age assessment reliability through Tooth Coronal Index (TCI) method. Material and Methods: The cone-beam computed tomography (CBCT) scans of 160 individuals aged between 20-70 years were analyzed in the present study. The height of the crown, i.e., coronal height, and the height of the coronal pulp cavity, i.e., coronal pulp cavity height, of mandibular second premolars and first molars were calculated and then TCI was measured. The actual age of a subject was compared with TCI of tooth and the acquired data were subjected to Pearson's correlation and unpaired t-tests. Results: Negative correlation was observed between the real age and TCI of mandibular first molar (r = -0.094, p=0.382) and second premolar (r = -0.176, p=0.0961. Statistically significant difference was observed between actual age and TCI for mandibular second premolar and first molar (p<0.001). Conclusion: Tooth coronal index has the potential to estimate age of an individual on CBCT scans. It is simple, cost-effective than histological methods and can be applied to both living and unknown dead.

Identification of dental calcification stages as a predictor of skeletal development phase

ABSTRACT Objective: This study aimed to establish a correlation between the stages of tooth calcification of mandibular canines and second molars with the phases of skeletal development. Methods: In a consecutive series of panoramic, cephalometric and hand-wrist radiographs of 113 individuals (60 females and 53 males) with an average age of 12.24 ± 1.81 years, the stages of mandibular canine and second molar calcification, cervical vertebrae maturation indicators (CVMI) and skeletal maturity indicators (SMI) were classified. The variables were correlated by means of the Spearman's Rank test: chronological age, SMI, CVMI and tooth calcification stages. In order to assess whether the CVMI and tooth calcification stages were significant predictors of the SMI, an ordinal regression analysis was carried out. Results: The stages of CVMI (OR = 16.92; CI 95% = 6.45-44.39; p< 0.001) and calcification of the second molars (OR = 3.22; CI 95% = 1.50-6.92; p= 0.003) were significant predictors of SMI, however similar result was not observed for canines (OR = 0.52, CI 95% = 0.18-1.54; p= 0.239). Calcification stage E for boys, and E and F for girls corresponded to the pre-peak phase of pubertal growth. Stages G and H for boys, and F and G for girls coincided with peak of growth. In the final growth phase, the majority of second molars presented with root apex closure (stage H). Conclusion: The stages of calcification of the second molar may be considered predictors of the stage of skeletal development in the population studied.

RESUMO Objetivo: O presente estudo objetivou estabelecer uma correlação entre os estágios de calcificação dentária de caninos e segundos molares inferiores e as fases do desenvolvimento esquelético. Métodos: Em uma série consecutiva de radiografias panorâmicas, cefalométricas e de mão e punho de 113 indivíduos (60 meninas e 53 meninos) com idade média de 12,24 ± 1,81 anos, foram classificados os estágios de calcificação do canino e do segundo molar inferiores, indicadores de maturação das vértebras cervicais (IMVC) e indicadores de maturação esquelética (IME). As variáveis foram correlacionadas pelo teste de Correlação de Rank de Spearman: idade cronológica, IME, IMVC e estágios de calcificação dentária. A fim de avaliar se os estágios do IMVC e da calcificação dentária foram preditores significativos do IME, foi realizada uma análise de regressão ordinal. Resultados: Os estágios de IMVC (OR = 16,92; IC 95% = 6,45-44,39; p< 0,001) e calcificação dos segundos molares (OR = 3,22; IC 95% = 1,50-6,92; p= 0,003) foram preditores significativos de IME; no entanto, esse não foi o caso com dentes caninos (OR = 0,52, IC 95% = 0,18-1,54; p= 0,239). Os estágios de calcificação E para meninos e E e F para meninas corresponderam à fase pré-pico de crescimento puberal. Os estágios G e H para meninos e F e G para meninas coincidiram com o pico de crescimento. Na fase final de crescimento, a maioria dos segundos molares apresentou fechamento do ápice radicular (estágio H). Conclusão: Os estágios de calcificação do segundo molar podem ser considerados preditores do estágio de desenvolvimento esquelético na população estudada.

Age determination in subadults using histological analysis of bones / Determinación de la edad en subadultos usando análisis histológico de los huesos

Abstract Introduction: According to the literature, the amount of osteons has been suggested as a good proxy to determine the age of death in adults. However in subadults research has not been carried out yet. Objective: To determine the accuracy of the histomorphometric technique predicting the age at death in subadults using bone remains. Methodology: The information of static histomorphometric parameters from about 120 iliac bones retrieved from the exhumed remains of subadults whose age at death was known was taken from the Granada collection. In order to predict the age at death we performed a step by step linear regression to estimate the fittest model. Results: The most closely and significantly associated biopsy findings with age were: the osteon count, the internal cortical width, and the trabecular bone volume. Pearson's correlation index indicated a weak linear association among these variables. To assess the accuracy of the model we used a coefficient of determination with a 0.32 value. 32% of the age variation in the subadults was explained by the three variables. Conclusion: This regression model explains a percentage of the total age variation in the subadult population. However this model is not enough to determine the age at death.

Resumen Introducción: La capacidad de predicción de las osteonas para determinar la edad de muerte de los individuos ha sido descrito en la literatura científica. No obstante, no se ha determinado dicha capacidad en individuos subadultos. Objetivo: Determinar la eficacia de lo parámetros histomorfometricos en población subadulta. Metodología: Se realizaron biopsias de hueso ilíaco en los restos de 120 subadultos, de la Colección Osteológica de Granada, con edad conocida en el momento de la muerte. Para establecer la capacidad de predicción se utilizó el R2 obtenido a partir de regresión lineal múltiple. Resultados: Las variables con mayor nivel predictivo y significativo para la estimación de la edad fueron: recuento de osteonas tipo 2 de la cortical interna y externa, y el volumen óseo trabecular; En la evaluación del modelo, se obtuvo un coeficiente de determinación de 0.32, es decir, el 32% de la variación en la edad de los subadultos se explica por el modelo. Sin embargo, se evidenció diferencias en la capacidad de predicción por sexo. Conclusión: Este modelo de regresión explica un porcentaje sustancial de la varianza de la edad de los individuos en la muestra. No obstante, no es suficiente para garantizar una adecuada predicción de la edad al momento de muerte de los individuos subdultos.

Research Progress and Prospect of Machine Learning in Bone Age Assessment / 法医学杂志

Bone age assessment has always been one of the key issues and difficulties in forensic science. With the gradual development of machine learning in many industries, it has been widely introduced to imageology, genomics, oncology, pathology, surgery and other medical research fields in recent years. The reason why the above research fields can be closely combined with machine learning, is because the research subjects of the above branches of medicine belong to the computer vision category. Machine learning provides unique advantages for computer vision research and has made breakthroughs in medical image recognition. Based on the advantages of machine learning in image recognition, it was combined with bone age assessment research, in order to construct a recognition model suitable for forensic skeletal images. This paper reviews the research progress in bone age assessment made by scholars at home and abroad using machine learning technology in recent years.

Research Progress on Automatic Assessment of Bone Age / 法医学杂志

Bone age is an important indicator of human growth and development, which can objectively reflect the growth level and maturity of individuals. Traditional manual bone age assessment usually compares the X-ray of the left wrist with the reference standard to obtain the corresponding bone age. This method is time-consuming and its results vary with different observers. In recent years, with the continuous development of computer science, bone age assessment has began to change from traditional manual assessment to automatic assessment. Although there has already been numerous researches on automatic bone age assessment, most of them are still in the experimental stage. This paper reviews related research and progress on automatic bone age assessment at home and abroad in recent years, in order to provide reference and research ideas for relevant researchers.

Research Progress on the Forensic Age Estimation in Living Individuals Using MRI / 法医学杂志

One of the major tasks in the forensic field is age estimation in living individuals, especially in adolescents and young adults. The X-ray examination of left hand, panoramic radiograph and CT scan of the sternal end of clavicles are mature means that are widely used. However, the X-ray technique has great radiation on the human body, and imaging radiation for non-diagnosis and treatment purposes does not conform to the current mainstream medical ethics. MRI is nonradioactive tomographic imaging and is one of the research and development directions in forensic age estimation in living individuals now. This paper summarizes the common indicators and analysis methods of MRI in previous research of age estimation, in order to get better understanding of its trends and provide a clue for future relevant studies.

Research Progress of Adult Age Determination with Imaging Methods / 法医学杂志

Adult age determination plays an important role in individual identification, criminal investigation and social welfare. The most popular adult age determination indicators are pubic symphysis, iliac auricular surface, costal cartilage, cranial sutures, teeth, laryngeal cartilage, etc. In recent years, with the progress of CT imaging and 3D reconstruction technology, the adult age determination study gradually has transferred from a time-consuming general observation of bones with complex pre-processing in the past to the non-destructive, convenient, time-saving and easy to store image analysis technology. To explore more accurate, rapid and convenient adult age determination methods, multiple imaging methods and artificial intelligence have been applied in adult age determination. This paper reviews the common methods and research progress of adult age determination at home and abroad, infers the development direction of adult age determination, in order to provide reference for the improvement and optimization of forensic adult age determination.

Comparison of Three CNN Models Applied in Bone Age Assessment of Pelvic Radiographs of Adolescents / 法医学杂志

Objective To compare the performance of three deep-learning models （VGG19, Inception-V3 and Inception-ResNet-V2） in automatic bone age assessment based on pelvic X-ray radiographs. Methods A total of 962 pelvic X ray radiographs taken from adolescents （481 males, 481 females） aged from 11.0 to 21.0 years in five provinces and cities of China were collected, preprocessed and used as objects of study. Eighty percent of these X ray radiographs were divided into training set and validation set with random sampling method and used for model fitting and hyper-parameters adjustment. Twenty percent were used as test sets, to evaluate the ability of model generalization. The performances of the three models were assessed by comparing the root mean square error （RMSE）, mean absolute error （MAE） and Bland-Altman plots between the model estimates and the chronological ages. Results The mean RMSE and MAE between bone age estimates of the VGG19 model and the chronological ages were 1.29 and 1.02 years, respectively. The mean RMSE and MAE between bone age estimates of the Inception-V3 model and the chronological ages were 1.17 and 0.82 years, respectively. The mean RMSE and MAE between bone age estimates of the Inception-ResNet-V2 model and the chronological ages were 1.11 and 0.84 years, respectively. The Bland-Altman plots showed that the mean value of differences between bone age estimates of Inception-ResNet-V2 model and the chronological ages was the lowest. Conclusion In the automatic bone age assessment of adolescent pelvis, the Inception-ResNet-V2 model performs the best while the Inception-V3 model achieves a similar accuracy as VGG19 model.