A Importância dos Métodos de Determinação das Idades Esquelética e Dentária na Ortodontia e Odontopediatria ­ uma Revisão de Literatura / The Importance of Methods for Determination of Squeletal and Dental Age in Orthodontics and Pediatric Dentistry ­ a Literature Review

O estágio de desenvolvimento humano é intimamente relacionado à sua maturidade óssea ou dentária, sendo essencial para a escolha do tratamento de alterações dentofaciais em crianças e adolescentes por ortodontistas e odontopediatras. Existem diversos indicadores biológicos para determinar a maturação do indivíduo, como a idade cronológica e as alterações hormonais, porém esses indicadores podem sofrer interferências. Visando uma determinação de desenvolvimento e dos picos de crescimento mais precisa, para um melhor diagnóstico e plano de tratamento, foram desenvolvidos diversos métodos para determinar a idade esquelética e a idade dentária, sendo estes a avaliação da maturação carpal, da morfologia das vértebras cervicais, da fusão óssea da sincondrose esfeno-occipital e da sutura palatina mediana, bem como dos estágios da calcificação dentária. A avaliação das radiografias de mão e punho é o padrão ouro da predição da idade esquelética, e sua correlação com outros métodos já é evidente. Sendo assim, é possível utilizar a avaliação das vértebras cervicais e das idades dentárias de Nolla e Demirjian.

The stage of human development is closely related to bone or dental maturity, being essential for the choice of treatment for dentofacial changes in children and adolescents by orthodontists and pediatric dentists. There are several biological indicators to determine an individual's maturation, such as chronological age and hormonal changes, but these indicators can suffer interference. Aiming at a more accurate determination of development and growth peaks, for a better diagnosis and treatment plan, several methods have been developed to determine skeletal age and dental age, these being the assessment of carpal maturation, the morphology of the cervical vertebrae, bone fusion of the spheno-occipital synchondrosis and the median palatal suture, as well as the stages of dental calcification. The evaluation of hand and wrist radiographs is the gold standard for predicting skeletal age, and its correlation with other methods is already evident. Therefore, it is possible to use the assessment of cervical vertebrae and dental ages by Nolla and Demirjian.

Accuracy of bone age assessment system based on deep learning in children with abnormal growth and development / 中华放射学杂志

Objective:To explore the accuracy of artificial intelligence (AI) system based on deep learning in evaluating bone age of children with abnormal growth and development.Methods:The positive X-ray films of the left wrist of children with abnormal growth and development who were treated at the Affiliated Hospital of Guizhou Medical University from January 2020 to December 2021 were collected retrospectively. A total of 717 children were collected, including 266 males and 451 females, aged 2-18 (11±3) years. Based on Tanner Whitehouse 3 (TW 3)-RUS (radius, ulna, short bone) and TW3-Carpal (carpal bone) method, bone age was measured by 3 senior radiologists, and the mean value was taken as reference standard. The bone ages were independently evaluated by the AI system (Dr.Wise bone age prediction software) and two junior radiologists (physicians 1 and 2). The accuracy within 0.5 year, the accuracy within 1 year, the mean absolute error (MAE) and the root mean square error (RMSE) between the evaluation results and the reference standard were analyzed. Paired sample t-test was used to compare MAE between AI system and junior physicians. Intraclass correlation coefficient (ICC) was used to evaluate the consistency between AI system, junior physician and reference standard. The Bland-Altman diagram was drawn and the 95% consistency limit was calculated between AI system and reference standard. Results:For TW3-RUS bone age, compared with the reference standard, the accuracy within 0.5 year of AI system, physician 1 and physician 2 was 75.3% (540/717), 62.1% (445/717) and 66.2% (475/717), respectively. The accuracy within 1 year was 96.9% (695/717), 86.3% (619/717) and 89.1% (639/717), respectively. MAE was 0.360, 0.565 and 0.496 years, and RMSE was 0.469, 0.634 and 0.572 years, respectively. For TW3-Carpal bone age, compared with the reference standard, the accuracy within 0.5 year of AI system, physician 1 and physician 2 was 80.9% (580/717), 65.1% (467/717) and 71.7% (514/717), respectively. The accuracy within 1 year was 96.0% (688/717), 87.3% (626/717) and 90.4% (648/717), respectively. MAE was 0.330, 0.527 and 0.455 years, and RMSE was 0.458, 0.612, 0.538 years, respectively. Based on TW3-RUS and TW3-Carpal bone age, the MAE of AI system were lower than those of physician 1 and physician 2, and the differences were statistically significant ( P all<0.001). The evaluation results of AI, physician 1 and physician 2 were in good agreement with the reference standard (ICC all>0.950). The Bland-Altman analysis showed that the 95% agreement limits of AI system for assessing TW3-RUS and TW3-Carpal bone age were -0.75-1.02 years and-0.86-0.91 years, respectively. Conclusion:The accuracy of AI system in evaluating the bone age of children with abnormal growth and development is close to that of senior doctors, better than that of junior doctors, and in good agreement with senior doctors.

Clinical application differences between TW3-Carpal and TW3-RUS based artificial intelligence-assisted bone age assessment system: a real-world pilot study / 中华放射学杂志

Objective:To investigate the differences between Tanner-Whitehouse (TW)3-Carpal and TW3-RUS(radius, ulna and short bone)-based artificial intelligence (AI)-assisted bone age assessment system using real world data.Methods:The image data of 262 children who received X-ray examination of left wrist in the Affiliated Children′s Hospital, Capital Institute of Pediatrics from July to September 2021 were retrospectively collected. The AI bone age assistant methods based on TW3-RUS and TW3-Carpal criteria were used to obtain the bone age results, respectively. Two senior pediatric radiologists evaluated the bone age on the basis of TW3-RUS and TW3-Carpal criteria, and the averaged values of two reviewers was calculated and taken as the gold standard reference. The cases were stratified into six age groups at 3-year intervals according to the gold standard reference, including 1-3 ( n=10), 4-6 ( n=35), 7-9 ( n=70), 10-12 ( n=118), 13-15 ( n=27) and 16-18 ( n=2) years old groups. Intraclass correlation coefficient (ICC) was used to evaluate the consistency between AI results and the gold standard bone age results. Pearson correlation method was used to measure the reliability between AI results and the gold standard results. The difference of bone age results between using TW3-RUS and TW3-Carpal criteria in different age groups was compared using paired t-test. Results:As for the whole sample, the results based on TW3-RUS criteria were 8.9±3.1 years old for AI assessment and 8.7±2.9 years old for the golden standard reference, with the ICC of 0.983; and the results based on TW3-Carpal criteria were 8.7±3.0 years old for AI and 8.8±2.8 years old for the golden standard reference, with the ICC of 0.976. Positive correlation were found in both TW3-RUS ( r=0.985, P<0.001) and TW3-Carpal criteria groups ( r=0.978, P<0.001). There were significant differences between TW3-RUS and TW3-Carpal at age groups of 7-9( t=-3.36, P=0.001), 10-12( t=-1.77, P=0.046), and 13-15 years old ( t=1.84, P=0.040). The bone age assessment using TW3-RUS and TW3-Carpal criteria were both in good agreement with the gold standard reference in age group of 4-6 years old (ICC=0.929 and 0.940), as well as in age group of 7-9 years old (ICC=0.882 and 0.927, respectively), with the results using TW3-Carpal criteria were slightly higher. As for the age groups of 10-12 and 13-15 years old, the method using TW3-RUS criteria showed excellent agreement with the gold standard reference (ICC=0.962 and 0.963, respectively), which were better than the performance of method using TW3-Carpal criteria (ICC=0.744 and 0.605, respectively). Conclusions:AI-assisted bone age system based TW3-Carpal and TW3-RUS criteria both show good reliability and accuracy in the bone age measurements. The AI method based TW3-Carpal criteria shows better performance in age group of 4-9 years old, while the method based on TW3-RUS criteria may be better for children of age 10-15 years old.

Applicability analysis of bone age assessment standards for children in rural areas of Beijing / 中华放射学杂志

Objective:To evaluate the applicability of bone age (BA) assessment methods and to investigate the difference between BA and chronological age (CA) based on the data of children in rural areas of Beijing.Methods:A total of 412 healthy children (226 boys, 186 girls) with the age 8.6 (6.8, 10.3) years old were included in this study. The data of the prospective study were from a subgroup of the project "National Nutrition and Health Systematic Survey for 0-18 Years Old Children in China", which included children with age of 3-12 years old in Beijing rural areas. The non-dominant hand-wrist radiographs of all participants were obtained in April 2021. The Dr.Wise BA detection and analysis system was used to assess the BA according to the Tanner Whitehouse 3 (TW3) radius-ulna-short bone score (TW3-RUS), TW3 carpal bone score (TW3-Carpal), China-05 TW3-Chinese RUS (TW3-C RUS), China-05 TW3-Chinese carpal (TW3-C Carpal), and Greulich-Pyle (G-P) standards. The cases were stratified by the sex and different CA in the statistical analysis. The estimated BA obtained using different methods were compared with the CA using Wilcoxon signed ranks test.Results:The sex-stratified results showed that no significant difference was found between the estimated BA using G-P standards and CA in boys ( Z=-0.694, P=0.488), while all the other estimated BA results were statistically significantly higher than CA ( P<0.05). Stratified by both sex and CA, the estimated BA using G-P standards in 4-6 years old boy groups, as well as the estimated BA using TW3-Carpal and TW3-C Carpal standards in 11-12 years old girl groups were lower than CA, while in the other groups, the estimated BA were higher than CA. Conclusions:There were varying degrees of deviations in the BA estimations using TW3, China 05, and G-P methods for children in rural areas of Beijing. It is imperative to establish a new standard for the BA evaluation of the contemporary Chinese children.

Sampling study design and radiography protocol of a large-sample investigation on skeletal maturation in 3 to 18-year-old children in China / 中华放射学杂志

Objective:To report the sampling study design and radiography protocol of a large-sample investigation on skeletal maturation of 3 to 18-year-old children in China.Methods:Multi-stage stratified random sampling was employed in this study. Two provinces, municipalities, or autonomous regions were randomly selected from each of the seven regions of China, including Northeast China, Northwest China, North China, Central China, East China, Southwest China, and South China. Then one rural and one urban investigation site were randomly selected from each province, municipality, or autonomous region. In total 28 sites were included. Among those sites, four residential districts were randomly selected from each urban site, and four townships from each rural site. For each residential district or township, 1-4 kindergartens, primary schools, and middle schools were chosen. Random cluster sampling was used to extract 3-<6-year-old children in kindergartens, and 6-18-year-old children in primary schools and middle schools. The investigation on skeletal maturation was sampled proportionate to the sampling of the whole study. The estimated simple size was 780 for each site, and 21 840 for all 28 sites in total. There were six groups of 3-<6-year-old children classified at 0.5-year intervals, and 12 groups of 6-18-year-old children classified at 1-year intervals. Posteroanterior position radiography of the left hand and wrist was achieved for all subjects.Results:The study was performed from August 26, 2019 to October 16, 2021. In total, 20 444 children received posteroanterior position radiography of the left hand and wrist, including 10 196 males and 10 248 females, 9 711 urban and 10 733 rural, respectively. The 3-<6-year-old group included 1 611 (male 819, female 792) subjects, and the 6 to 18-year-old group included 18 833 (male 9 377, female 9 456) subjects.Conclusion:This nationwide investigation on skeletal maturation of 3 to 18-year-old children in seven regions of China was successfully preformed. The results of this study can provide an important reference for establishing the current evaluation criteria of bone age in Chinese children and adolescents.

Transphyseal anterior cruciate ligament reconstruction in skeletally immature pubescent adolescents / 中华骨科杂志

Objective:To evaluate the safety and clinical efficacy of transphyseal anterior cruciate ligament (ACL) reconstruction with hamstring autograft in skeletally immature pubescent adolescents.Methods:Retrospectively reviewed 10 skeletally immature pubescent patients (10 knees) who underwent transphyseal ACL reconstruction with hamstring autograft between May 2015 and May 2020 in our center. Out of the 10 patients, 6 were males aged 14.2±1.4 years (range, 13-15 years) with bone age 13-15 years, 4 were females aged 12.4±1.2 years (range, 11-13 years) with bone age 11-13 years. The average duration from injury to surgery was 8.3±5.3 months (range, 3-48 months). Before operation, left hand and wrist plain film were done to assess bone age. Before operation and at follow up, physical examination, KT-1000 measurements and functional outcome instruments (the Lysholm score, and the Tegner score) were done. Radiographs were performed for angular deformity and leg-length measurements. The surgery was conducted via arthroscopically assisted transphyseal reconstruction of the ACL with use of an autogenous quadrupled hamstring tendon graft and fixation devices that did not cross the physes. A protective knee brace was used for 1 month postoperatively. Comparison of Lysholm score and Tegner score before and after surgery was performed using t test. Results:Arthroscopy confirmed ACL rupture in 10 knees. Concurrent meniscal surgery was performed in 3 knees. The follow-up duration was 3.2±2.3 years (range 2-5 years), one of 10 patients had ligament reinjury 1 year after surgery with positive anterior drawer test and Lachman test. As for the remaining 9 patients, the mean Lysholm knee score improved from preoperative 76.1±8.2 to 95.8 ±3.5, and the mean Tegner score improved from preoperative 4.3±0.9 to 8.3±0.6, both of the two outcomes had statistically significant difference ( t=6.43, P=0.024; t=4.41, P=0.033). One patients was weakly positive for anterior drawer test and Lachman test, with KT-1000 side difference >3 mm, the remaining eight were negative for anterior drawer test and Lachman test, and KT-1000 side difference was mean 1.7±0.7 mm. All patients had no more than 5° restriction in knee range of motion compared with the healthy side. The full-length X-ray of the standing lower limbs showed no length and angle deformity in both lower limbs. Conclusion:Transphyseal ACL reconstruction with autogenous quadrupled hamstring graft in treating skeletally immature pubescent patients (bone age over 13 years in male and 11 years in female) yields satisfied functional outcomes without growth disturbance.

Clinical study on thyroid function in children with congenital hypothyroidism / 中国基层医药

Objective:To investigate thyroid function, physical growth, and psychological and behavioral development in children with congenital hypothyroidism.Methods:Thirty-two children with congenital hypothyroidism who were born in Yuyao People's Hospital from January 2014 to December 2018 were included in the observation group. Thirty healthy neonates who were born in the same period were included in the control group. Thyroid function index changes at the age of 1 year relative to at birth, physical, intellectual, and neuropsychological development and bone age at the age of 1 year were compared between the observation and control groups.Results:Thyroid-stimulating hormone level at birth was significantly higher in the observation group than in the control group [(18.23 ± 2.71) mU/L vs. (2.85 ± 0.34) mU/L, t = 30.84, P < 0.001]. Free thyroxine level at birth was significantly lower in the observation group than in the control group [(6.76 ± 1.54) pmol/L vs. (17.91 ± 2.04) pmol/L, t = 24.39, P < 0.001]. In the observation group, thyroid-stimulating hormone and free thyroxine levels at the age of 1 year were (2.68 ± 0.78) mU/L and (17.26 ± 2.11) pmol/L, respectively, which were not significantly different from those in the control group [(2.77 ± 0.63) mU/L and (17.54 ± 2.20) pmol/L, t = 0.50, 0.51, both P > 0.05]. Body weight, body length, head circumference, and bone age at the age of 1 year were (9.21 ± 1.20) kg, (79.84 ± 3.05) cm, (43.73 ± 1.42) cm, (1.01 ± 0.15) years old, respectively in the observation group, which were significantly lower than those in the control group [(10.12 ± 1.32) kg, (84.54 ± 3.41) cm, (45.85 ± 2.04) cm, (1.14 ± 0.28) years old, t = 2.84, 5.73, 4.77, 2.30, P < 0.05]. The proportion of children patients with bone age lag was significantly higher in the observation group than in the control group [21.88% (7/32) vs. 3.33% (1/30), χ2 = 4.74, P < 0.05]. There was a significant difference in intellectual development at the age of 1 year between the two groups ( χ2 = 7.05, P < 0.05). Gross movement, fine movement, adaptability, language ability, and social ability in the observation group were scored (90.43 ± 6.96) points, (92.03 ± 6.03) points, (88.45 ± 4.85) points, (84.04 ± 5.71) points, and (85.05 ± 6.17) points, respectively, which were significantly lower than those in the control group [(99.47 ± 5.40) points, (104.12 ± 5.71) points, (98.47 ± 5.22) points, (94.16 ± 4.98) points, and (104.34 ± 5.70) points ( t = 5.69, 8.09, 7.84, 7.42, 12.76, all P < 0.001]. Conclusion:Neonate patients with congenital hypothyroidism have obvious physical growth and psychological and behavioral development disorders. Early screening and treatment of neonatal congenital hypothyroidism should be strengthened to improve the prognosis.

Effect of oral acitretin on the height and bone development of children: a retrospective analysis of 106 cases / 中华皮肤科杂志

Objective:To evaluate the effect of oral acitretin on the height and bone development of children.Methods:Clinical and imaging data were collected from 106 children receiving oral acitretin for at least 1 month in Department of Dermatology, Beijing Children′s Hospital from March 2007 to January 2021, and retrospectively analyzed. The main outcome measures were height and near-adult height. Multivariate logistic regression analysis was carried out to investigate relevant factors for short stature in children, and non-inferiority test was used to analyze the proximity of the actual height to target height of children who had reached near-adult height. The secondary outcome measures were bone age and epiphyseal closure. Wilcoxon signed-rank test was used to analyze differences in the value of bone age minus chronological age between the baseline and last follow-up, and the premature closure of epiphysis was also evaluated.Results:Among the 106 children, 62 were males and 44 were females; 84 were diagnosed with pustular psoriasis, 10 with psoriasis vulgaris, 11 with pityriasis rubra pilaris, and 1 with lupus miliaris disseminatus faciei. These children received oral acitretin at doses of <1 mg·kg -1·d -1 for 1 - 90 months. Among the 96 children aged under 18 years, 91 (94.8%) were of normal stature, and 5 (5.2%) were short in stature; among the 83 children receiving acitretin monotherapy, 81 (97.6%) were of normal stature, and 2 (2.4%) of short stature. Binary logistic regression analysis showed that the risk of short stature caused by acitretin combined with glucocorticoid therapy was 76.57 times higher than that of acitretin monotherapy ( OR = 77.57, 95% CI: 2.20 - 2 738.82, P = 0.017) , while the type of disease, gender, age at onset, age at initial treatment with acitretin, course of treatment, and average daily dose of acitretin did not significantly affect the stature of children ( P = 0.988, 0.214, 0.087, 0.078, 0.066, 0.350, respectively) . At the last follow-up visit, 13 children who had reached near-adult height were of normal stature, and the non-inferiority test showed that their near-adult height was not inferior to the target height (Satterthwaite = 0.23, P = 0.030) . Bone age was evaluated in 45 children at baseline and last follow-up visit, there was no significant difference in the value of bone age minus chronological age between the baseline and last follow-up ( Z = -0.85, P = 0.250) , and no patients experienced premature closure of epiphysis before and after the treatment. Conclusion:This study preliminarily revealed that oral acitretin at doses of <1 mg·kg -1·d -1 for less than 90 months might not significantly affect the height and bone development of children.

Adult Age Estimation of CT Image Reconstruction of the Laryngeal Cartilages and Hyoid Bone Based on Data Mining / 法医学杂志

Objective To explore the feasibility of the CT image reconstruction of laryngeal cartilage and hyoid bone in adult age estimation using data mining methods. Methods The neck thin slice CT scans of 413 individuals aged 18 to <80 years were collected and divided into test set and train set, randomly. According to grading methods such as TURK et al., all samples were graded comprehensively. The process of thyroid cartilage ossification was divided into 6 stages, the process of cricoid cartilage ossification was divided into 5 stages, and the synosteosis between the greater horn of hyoid and hyoid body was divided into 3 stages. Multiple linear regression model, support vector regression model, and Bayesian ridge regression model were developed for adult age estimation by scikit-learn 0.17 machine learning kit （Python language）. Leave-one-out cross-validation and the test set were used to further evaluate performance of the models. Results All indicators were moderately or poorly associated with age. The model with the highest accuracy in male age estimation was the support vector regression model, with a mean absolute error of 8.67 years, much higher than the other two models. The model with the highest accuracy in female adult age estimation was the support vector regression model, with a mean absolute error of 12.69 years, but its accuracy differences with the other two models had no statistical significance. Conclusion Data mining technology can improve the accuracy of adult age estimation, but the accuracy of adult age estimation based on laryngeal cartilage and hyoid bone is still not satisfactory, so it should be combined with other indicators in practice.

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.

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.

Establishment of Mathematical Models for Skeletal Age Determination of Extremitas Sternalis of Clavicle in Shanxi Adolescents / 法医学杂志

Objective To develop mathematical models for skeletal age determination with multiple statistic method based on the correlation between age and the growth of the epiphysis of extremitas sternalis of clavicle in Shanxi adolescents. Methods The 562 Shanxi sternoclavicular joint samples （454 cases of modelling, 108 cases of external verification） were scanned by the thin-section computed tomography. After volume rendering was obtained, indicators such as area of epiphysis, area of metaphysis, longest diameter of epiphysis and longest diameter of metaphysis of both extremitas sternalis of clavicle were collected. Indicators such as the ratio of area of epiphysis to area of metaphysis, and the ratio of longest diameter of epiphysis to longest diameter of metaphysis of both sides were calculated. Then multiple linear regression and random forest discriminant models were used to build mathematical models for age determination of adolescents. Results The obtained indicators exhibited a strong correlation with age （r>0.85）. The multiple linear regression model for males and females （all 4 indicators entering the model） based on the ratio of longest diameter of epiphysis to longest diameter of metaphysis and the ratio of area of epiphysis to area of metaphysis had an internal validation accuracy rate （±1.0 year） of over 92% and 108 cases had an external validation accuracy rate of over 70% （±1.0 year）. The out of bag error rates of random forest discriminant models were less than 2% for people over 18.0 years old （≥18.0 years old） and under 18.0 years old. The external validation accuracy rates of the 108 cases were over 80%. Conclusion The regression and discriminant models established in this study have certain reliability and accuracy and can be used in age determination of Shanxi adolescents.

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.

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.

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 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 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.

The Reliability of Fishman and Nolla Methods in Prediction of Chronological Age of Yemeni Children / A confiabilidade dos métodos Fishman e Nolla na predição da idade cronológica de crianças iemenitas

Objective: This cross-sectional school based study aimed to assess the reliability of Fishman and Nolla methods in predicting the chronological age for Yemeni children. Material and Methods: Orthopantomographs and left handwrist radiographs were taken for 358 Yemeni children (193 boys and 165 girls) 8 - 16 years. Skeletal age estimated by Fishman method and dental age estimated by Nolla method were compared to chronological age using SPSS version 21, statistical significance was predetermined at P < 0.05 , using Intraclass Correlation CoefficientICC and Wilcoxon signed rank test. Results: The mean chronological, skeletal and dental ages were 12.00 ± 2.25 years, 12.39 ± 1.65 years and 11.32 ± 2.65 years, respectively. Intraclass correlation coefficient showed strong correlation between chronological age and skeletal and dental ages. Wilcoxon test showed Fishman method significantly underestimated the chronological age by 0.44 ± 1.26 years in boys and non-significantly underestimated the chronological age by 0.02 ± 1.08 years in girls. Nolla method significantly underestimated the chronological age by 0.59 ± 1.28 years in boys and 0.78 ± 1.21 years in girls. Conclusions: Chronological age of Yemeni children is highly correlated to skeletal age estimated by Fishman method and dental age estimated by Nolla method. However, the two methods underestimate the chronological age of Yemeni children.(AU)

Objetivo: Este estudo transversal de base escolar teve como objetivo avaliar a confiabilidade dos métodos Fishman e Nolla na predição da idade cronológica em crianças iemenitas. Material e Métodos: Foram realizadas ortopantomografias e radiografias do punho esquerdo em 358 crianças iemenitas (193 meninos e 165 meninas) de 8 a 16 anos. A idade esquelética estimada pelo método Fishman e a idade odontológica estimada pelo método Nolla foram comparadas com a idade cronológica pelo, utilizando-se o programa SPSS versão 21; a significância estatística foi predeterminada em P < 0,05, pelo coeficiente de correlação intraclasseICC e pelo teste de Wilcoxon. Resultados: As idades cronológica, esquelética e odontológica média foram de 12,00 ± 2,25 anos, 12,39 ± 1,65 anos e 11,32 ± 2,65 anos, respectivamente. O coeficiente de correlação intraclasse mostrou forte correlação entre idade cronológica e idade esquelética e dentária. O teste de Wilcoxon mostrou que o método Fishman subestimou significativamente a idade cronológica em 0,44 ± 1,26 anos nos meninos e não subestimou significativamente a idade cronológica em 0,02 ± 1,08 anos nas meninas. O método Nolla subestimou significativamente a idade cronológica em 0,59 ± 1,28 anos nos meninos e 0,78 ± 1,21 anos nas meninas. Conclusões: A idade cronológica de crianças iemenitas está altamente correlacionada à idade esquelética estimada pelo método Fishman e à idade dentária estimada pelo método Nolla. No entanto, os dois métodos subestimam a idade cronológica das crianças iemenitas.(AU)

Age estimation in Brazilian adults by Kvaals and Camerieres methods

Abstract The aim of this study was to verify the precision and applicability of two methods of age estimation, Kvaal's and Cameriere's methods, among Brazilian adults. A sample composed of periapical radiographs of canine teeth belonging to 320 Brazilian adults was analyzed, divided into groups according to sex (male and female) and age group (20-29 years, 30-39 years, 40-49 years and 50-59 years). Kvaal's method presented better results when compared to the results of Cameriere's method in the general evaluation of each canine tooth, except for the upper left canine (tooth 23), which presented a mean error (ME) with no statistically significant difference between the methods (Kvaal: ME = 7.43, p = 0.4991, Cameriere: ME = 7.55, p = 0.6982). In the evaluation by age groups, Kvaal's method presented a lower variation between the real age and estimated age when applied to the age groups of 20-29 years and 30-39 years compared to the results provided by Cameriere's method. With respect to the groups aged 40 to 49 years and 50 to 59 years, Cameriere's method presented better performance than the results provided by Kvaal's method. The methods of estimating age proposed by Kvaal and Cameriere are simple and nondestructive and have demonstrated reproducibility and reliability. The Kvaal method was more accurate for the age groups of 20-29 and 30-39 years, and for those over 40 years, the Cameriere method was the most accurate.

Comparative assessment of chronological, dental, and skeletal age in children

Background: Age of a child can be assessed from various parameters such as chronological age, height, weight, secondary sexual characteristics, skeletal age, or dental age. The present study was planned to assess and compare chronological age with dental age (Demirjian's method and Willem's method) and skeletal age (Fishman's method). Materials and Methods: The present study was done on a sample of 100 children in the age group of 9–14 years. The chronological age was computed through the birth certificates and dental age was calculated from their orthopantomograms (OPGs) using Demirjian's and Willem's methods. Hand-wrist radiograph of the left hand was used to compute skeletal age using Fishman's method. Paired t-test and Pearson's correlation coefficients were calculated as a part of statistical analysis at a significance level of P < 0.01. Results: The mean chronological age among the group was 12.37 ± 1.34 years, the mean dental age by Demirjian's method was 12.36 ± 1.72 years, the mean dental age by Willem's method was 12.36 ± 1.51, and the mean skeletal age by Fishman's method was 13.03 ± 1.34 years. Out of the all methods evaluated in the study, Fishman's method of age estimation showed the least value of correlation coefficient (r = 0.728) with the chronological age, whereas Willem's method showed the maximum correlation with the chronological age (r = 0.885). Conclusion: It can be concluded from the present study that the dental age estimation evaluated by the digital OPG by both the methods, that is, Demirjian's method and Willem's method, has shown high accuracy when applied to the children of Faridabad. Skeletal maturation evaluated by Fishman's method using hand-wrist radiographs was found to overestimate the age when compared to chronological age in both the sexes.