• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.3
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• pp.255-268
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• 2021

The aim of this study was to investigate the relationships between the stages of calcification of various teeth and skeletal maturity stages among Korean subjects. The samples were derived from hand-wrist, panoramic radiographs, and lateral cephalograms of 743 subjects (359 males and 384 females) with ages ranging from 6 to 14 years. Calcification of seven permanent mandibular teeth on the left side were rated according to the system of Demirjian. To evaluate the stage of skeletal maturation, hand-wrist radiographs were analyzed by skeletal maturity indicators (SMI) system of Fishman and lateral cephalograms by cervical vertebral maturation (CVM) method of Baccetti. Statistically significant relationships were found between dental calcification and skeletal maturity stages according to Spearman rank-order correlation coefficients (r = 0.40-0.84, p < 0.001). The second molar showed the highest correlation and central incisor showed the lowest correlation for female and male subjects. For both sexes, canine stage G and second molar stage F were related to SMI 6 and CS 3. Because of the high correlation coefficients, this study suggests that tooth calcification stages from panoramic radiographs might be clinically useful as a maturity indicator of the pubertal growth period in Korean patients.

• The korean journal of orthodontics
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• v.28 no.2 s.67
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• pp.285-295
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• 1998

In clinical orthodontics, it is significant to understand the stage of growth in a growing patient. In order to assess the skeletal maturity of the patients, the hand-wrist radiograph and the cervical vertebrae (Cervical Vertebrae Maturation Indicators : CVMI) was evaluated from the lateral cephalograph and the skeletal maturity determined from the hand-wrist X-ray (Skeletal Maurity Indicators : SMI) taken on the same day in the same patients, and its interrelationship examined to come up with the following results: 1. The skeletal maturity evaluated from the hand-wrist radiograph and the maturation of the cervical vertebrae from the lateral cephalograph showed a significant interrelationship with each other. 2. In the evaluation of the skeletal maturity using the SMI and CVMI, the CVMI 1 showed a siginificant correlation with SMI 1, 2, the CVMI 2 with SMI 3, 4, CVMI 3 with SMI 6, 7, CVMI 4 with SMI 7, 8, CVMI 5 with 9, 10 and CVMI 6 with SMI 11. 3. When the morphological changes in the 2nd and 3rd cervical vertebrae were separately observed, it was seldom that the concavity appeared in the lower border of the 2nd cervical vertebra and at the same time not appear in the 3rd cervical vertebra (CVMI 2 : 10.38%, CVMI 3 : 6.56%) 4. In each of the skeletal maturation stage evaluated from the hand-wrist and the cervical vertebra, the average age and its standard deviation in male and female patients appeared to have large differences among individuals. Skeletal maturation seemed to appear earlier for the girls than for the boys, and its termination 24 months faster for girls.

• Journal of the korean academy of Pediatric Dentistry
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• v.39 no.4
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• pp.357-365
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• 2012

There are orthodontic treatment which involves tooth movements and orthopedic treatment which involves skeletal movement. In childhood and adolescence, especially for the treatment of orthopedic treatment, the evaluation of bone maturity and growth potential is very important. The purpose of this study is to assess the developmental stage and to compare the amount of mandibular growth with cephalometric radiographs and hand-wrist radiograph in 6 to 13-year-old children with normal occlusion. The results are as follows : SMI and CVM showed a significant correlation (p < 0.05). Ar-Go, Co-Go, N-Go, S-Gn, N-Me, Co-Gn, Go-Me, Go-Gn increased with increasing maturity of hand-wrist and Ar-Go, Co-Go, N-Go, S-Gn, N-Me, Co-Gn, Go-Me, Go-Gn increased with increasing maturity of cervical vertebrae maturation. Also Ar-Go, Co-Go, N-Go, S-Gn, N-Me, Co-Gn, Go-Me, Go-Gn showed a significant correlation with each of the cervical vertebrae maturation stages and hand-wrist maturation stages (p < 0.05). These results suggested that mandibular growth had a significant correlation with cervical vertebrae maturation stages and hand-wrist maturation stages.

• Imaging Science in Dentistry
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• v.52 no.1
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• pp.83-91
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• 2022

Purpose: This study assessed the associations between chronological age, dental maturation (DM), cervical vertebrae maturation (CVM), and hand-wrist maturation (HWM) in individuals aged 9-19 years. In addition, this study aimed to derive practical methods to evaluate the skeletal age using DM, CVM, or HWM for orthodontic, medical, and forensic purposes and to compare which of these 3 developmental parameters is more accurate for estimating the age of individuals in a Turkish population. Materials and Methods: Panoramic, lateral cephalometric, and hand-wrist radiographs of 284 patients aged 9-19 years were used in this study. The DM, CVM, and HWM stages were determined. The Kolmogorov-Smirnov, kappa, Wilcoxon, Kruskal-Wallis, chi-square, and Spearman correlation tests and simple linear regression analysis were used for statistical analysis. The significance level was 0.05. Results: Statistically significant differences were found between chronological age and DM, chronological age and CVM, and chronological age and HWM in both sexes (P<0.05). DM did not show statistically significant differences according to sex (P>0.05), but CVM and HWM were statistically different between males and females (P<0.05). The DM-estimated age yielded more accurate values than the other methods. Conclusion: All correlations between skeletal and dental stages were statistically significant. Our results showed that there was no statistically significant difference between chronological age and DM-estimated age. Therefore, it can be concluded that DM stages have the potential to be used for legal purposes.

• Journal of Korea Multimedia Society
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• v.21 no.2
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• pp.98-107
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• 2018

In this paper, we propose a method to classify the skeletal maturity with a small amount of hand wrist X-ray image using deep learning-based meta-learning. General deep-learning techniques require large amounts of data, but in many cases, these data sets are not available for practical application. Lack of learning data is usually solved through transfer learning using pre-trained models with large data sets. However, transfer learning performance may be degraded due to over fitting for unknown new task with small data, which results in poor generalization capability. In addition, medical images require high cost resources such as a professional manpower and mcuh time to obtain labeled data. Therefore, in this paper, we use meta-learning that can classify using only a small amount of new data by pre-trained models trained with various learning tasks. First, we train the meta-model by using a separate data set composed of various learning tasks. The network learns to classify the bone maturity using the bone maturity data composed of the radiographs of the wrist. Then, we compare the results of the classification using the conventional learning algorithm with the results of the meta learning by the same number of learning data sets.

• Korean Journal of Radiology
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• v.22 no.5
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• pp.792-800
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• 2021

Bone age assessments are a complicated and lengthy process, which are prone to inter- and intra-observer variabilities. Despite the great demand for fully automated systems, developing an accurate and robust bone age assessment solution has remained challenging. The rapidly evolving deep learning technology has shown promising results in automated bone age assessment. In this review article, we will provide information regarding the history of automated bone age assessments, discuss the current status, and present a literature review, as well as the future directions of artificial intelligence-based bone age assessments.

• The korean journal of orthodontics
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• v.25 no.4
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• pp.415-423
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• 1995

In order to investigate the relationship between the menarche and the bone maturity of growing girls, the author interviewed about the date of menarche of 70 girls and assessed their bone maturity by hand-wrist radiographs. The results and conclusion were as iollows ; 1. The mean menarcheal age was $12.04{\pm}0.82$ year. 2. There was significant correlation between the time interval after menarche and the ossification stage. 3. The skeletal maturation level at menarche was stage SMI 7 and SMI 8. 4. There was statistically different among the time intervals after menarche according to the ossification stage. 5. The epiphyseal union of radius began about 2 years after menarche. According to this study, the probability of clinical use can be accepted in some range. In another words, skeletal age can be predicted by just interviewing the date and time interval of menarche without hand-wrist radiograph, also, with this information, the level of maxillofacial growth can be assessed.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.30.1-30.7
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• 2020

Background: Dental studies of precocious puberty have focused on examination of jaw and dentition growth. The aim of the study was to analyze the relationship between precocious puberty and maxillary dental developmental abnormalities (DDAs). Methods: This retrospective study was conducted on the Korean patients in whom dental panoramic and hand-wrist radiographs had been taken before they were 15 years of age. The maxillary DDAs were assessed as mesiodens, congenital missing teeth, peg-shape lateral incisors, or impacted teeth. The chronological ages of the control group members were within the normal range of the hand-wrist bone age. Others with a peak luteinizing hormone of ≥ 5 and < 5 IU/L were allocated to central precocious puberty (CPP) and peripheral precocious puberty (PPP), respectively. Results: Of the enrolled 270 patients, 195, 52, and 23 were allocated to the control, CPP, and PPP groups, respectively. The maxillary DDAs were significantly more prevalent in the CPP group than in the other groups. Among those with maxillary DDA, the mesiodens predominated. Age- and sex-adjusted multivariate analysis revealed maxillary DDA (odds ratio, 3.36; 95% CI, 1.60-7.05) and especially mesiodens (odds ratio, 5.52; CI, 2.29-13.28) to be significantly associated with CPP. Conclusions: Maxillary DDAs were significantly more prevalent in the CPP group than in the PPP or control groups. Among the many types of maxillary DDAs, mesiodens was significantly associated with CPP and may be considered a predictor of the development of CPP.

• The korean journal of orthodontics
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• v.39 no.2
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• pp.120-129
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• 2009

Objective: To estimate dental maturity using the Demirjian Index for the mandibular third molar and investigate the relationships between dental maturity and skeletal maturity among growing children. Methods: The samples were derived from panoramic, lateral cephalometric and hand-wrist radiographs of 270 female subjects registered as patients at the orthodontic department, dental hospital, Yonsei University. Dental maturity [Demirjian Index (DI)] and skeletal maturity [skeletal maturation indicators (SMIs)] and cervical vertebrae maturation indicators (CVMIs)] were estimated from these radiographs. Results: There was a significant correlation (r = 0.64) between SMIs and DI, and a similar correlation (r = 0.59) was observed between CVMIs and DI (p < 0.001). If DI was above Stage E, then the SMI was above Stage 10 and the CVMI was above Stage 5. There was a weak correlation (r = 0.26) between age at menarche and DI (p < 0.001). There was no significant difference in DI among Class I, II or III malocclusions. Conclusions: Dental maturity evaluation using the mandibular third molar will be an adjunctive tool in combination with cervical vertebrae and hand-wrist maturity evaluations.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.1
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• pp.48-56
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• 2019

The objective of this study was to examine measuring agreement between middle phalanx of the third finger and cervical vertebrae analysis for assessing skeletal maturity according to body mass index percentile. A retrospective chart view was used to select patients with body mass index data, hand - wrist radiographs and lateral cephalograms of same day. The patients were divided into 4 groups by body mass index percentile. The hand - wrist radiographs were analyzed using modified middle phalanx of the third finger method and the lateral cephalograms were categorized according to cervical vertebral maturation stage. The degree of agreement between the 2 methods of analyzing skeletal maturation was measured by calculating weighted kappa statistic according to body mass index percentile group. There was a good agreement between the 2 methods in the entire body mass index percentile group. According to the body mass index percentile group, the agreement was found to be different, and the pattern was different between boys and girls. Pediatric dentist should consider sex and weight status when evaluating growing children and adolescents because it can affect the agreement of 2 method of analyzing skeletal maturation.