Dental age assessment: the applicability of Demirjian's method in south Indian children

A New Approach for Analyzing Root Development in Autogenous Tooth Transplants Using Computed Tomography

INTRODUCTION

The aim of this study was to evaluate root development in autotransplanted teeth using cone-beam computed tomography (CBCT) images.

METHODS

Twelve premolars with incomplete root formation, which were selected to replace prematurely lost upper central incisors, were analyzed by CBCT on two different occasions. The first CBCT examination (T1) was conducted before tooth autotransplantation. The second CBCT examination (T2) was performed over a follow-up period of at least 12 months and < 5 years. Three previously calibrated evaluators assessed root development. The positions of the tomographic planes were standardized. The mean root length in sagittal and coronal tomographic sections was used to validate the root length at T1 and T2. Longitudinal root development of the transplanted tooth was determined by calculating the difference in root length between T2 and T1. The intraclass correlation coefficient (ICC), paired t-test, and Pearson test were applied, with significance set at 5%.

RESULTS

The mean time elapsed between T1 and T2 was 962 days/2.6 years. The ICC was > 0.75. The measurements obtained at T2 were significantly greater than at T1 (p = 0.001). The mean increase in root length was 2.83 mm. There was no significant correlation (p = 0.413; r = 0.261) between root length increase and the time elapsed between T1 and T2.

CONCLUSION

Premolar teeth with incompletely formed roots transplanted to the upper central incisor region showed continued root development during postoperative follow-up.

Bridging gaps in age estimation: a cross-sectional comparative study of skeletal maturation using Fishman method and dental development using Nolla method among Egyptians

Estimating the chronological age of humans is a prevalent need in forensic practice. Comparing the accuracy of different age identification methods helps provide the most reliable method for a specific population. This study aimed to compare the accuracy of age assessments using skeletal maturation and dental mineralization in a sample of Egyptians and to assess if combining both methods yields more precise age prediction. A cross-sectional study included 176 Egyptian children and adolescents aged between 8 and 16 who underwent orthopantomograms and hand-wrist radiographs. All radiographs were scored independently for skeletal maturation using the Fishman method and dental development using the Nolla method. While Fishman and Nolla methods were valid and reliable age predictors with variable sex and age group accuracy in Egyptians, the Nolla method showed superior performance. The Nolla method slightly underestimated the chronological age, while the Fishman method slightly over-estimated it, showing median differences of -0.21 and 0.17, respectively. Correlating the estimated age using the Fishman and Nolla methods and the chronological age showed intraclass correlation coefficients of (0.854 and 0.660) and (0.973 and 0.977) for females and males, respectively (P < 0.001). The model adopting the Nolla score exhibited the highest R² (0.973 and 0.968) and the lowest Akaike information criteria (96 and 106) for females and males, respectively, which is comparable to the model adopting both Nolla scores and skeletal maturation indicators. Therefore, we recommend adopting the model incorporating only the Nolla scores for age estimation without the need for further hand and wrist radiography.

Dental evidence for extended growth in early Homo from Dmanisi

Human life history is characterized by an extended period of immaturity during which there is a disjunction between cerebral and somatic growth rates1. This mode of ontogeny is thought to be essential for the acquisition of advanced cognitive capabilities in a socially complex environment while the brain is still growing2. Key information about when and how this pattern evolved can be gleaned from the teeth of fossil hominins because dental development informs about the pace of life history3-5. Here we show that the first evolutionary steps towards an extended growth phase occurred in the genus Homo at least 1.77 million years ago, before any substantial increase in brain size. We used synchrotron phase-contrast tomography6 to track the microstructural development of the dentition of a subadult early Homo individual from Dmanisi, Georgia. The individual died at the age of 11.4 ± 0.6 years, shortly before reaching dental maturity. Tooth growth rates were high, similar to rates in living great apes. However, the Dmanisi individual showed a human-like delayed formation of the posterior relative to the anterior dentition, and a late growth spurt of the dentition as a whole. The unique combination of great-ape-like and human-like features of dental ontogeny suggests that early Homo had evolved an extended growth phase before a general slow-down in life history, possibly related to biocultural reproduction7 rather than brain growth.

Radiological Evaluation of the Accuracy of Demirjian, Nolla, and Willems Methods for Dental Age Estimation in 3-17-Year-Old Iranian Children

Background: The stage of tooth formation is one of the most reliable indicators for predicting a patient's developmental age by radiographs. This study compared the accuracy of three distinct dental age estimation methods (Demirjian, Nolla, and Willems) in children aged 3-17 in the northern Iranian population. Methods: This cross-sectional study examined panoramic radiographs of 434 children aged 3-17 from Mazandaran Province, Iran, who had teeth 31-37 present on the left mandible. This study employed the Demirjian, Nolla, and Willems methods to estimate the dental age of the sample and compare it with the chronological age. The data were analyzed using SPSS v16. A paired t-test was used to compare chronological and dental ages. The Pearson correlation was used to correlate the chronological and dental ages. The errors of different methods were compared using the Wilcoxon test. P values < 0.05 were considered significant for all tests except Wilcoxon. For Wilcoxon, a P value < 0.017 was considered significant. Results: The three methods presented differing mean estimated ages. The Demirjian method delivered the highest mean, and all three methods differed significantly when compared in pairs. The results showed that the Demirjian method overestimated chronological age by 0.25 years (P < 0.001) in girls and 0.09 years (P = 0.28) in boys. The Willems method underestimated chronological age by 0.05 years (P = 0.47) in girls and 0.12 years (P = 0.13) in boys. The Nolla method underestimated chronological age by 0.41 years (P < 0.001) in girls and 0.40 years (P < 0.001) in boys. The accuracy of each method varied with the patient's age. Conclusion: According to the findings, the Willems method outperformed the Demirjian method, and the Demirjian method exceeded the Nolla method for estimating dental age in Iranian children aged 3-17. Overall, the Demirjian method overestimated the age of the study population, whereas the other two underestimated it.

Dental age estimation methods applied to Indian children and adolescents: A systematic review and meta-analysis

Country-specific systematic reviews and meta-analyses have been proposed to compile the available literature and rank methods based on their performance for a target population. India is a country with a vast scientific literature on dental age estimation. This systematic review aimed to provide evidence to help the decision of experts regarding the method of choice for dental age estimation in India. The research protocol was registered in Open Science Framework. Literature Search was performed in Embase, LILACS, MedLine (via PubMed), SciELO, Scopus and Web of Science. Grey Literature was searched in Google Scholar and ProQuest. Observational cross-sectional studies that compared chronological and estimated ages using Demirjian (original [DEM] and Chaillet's modification [modified-DEM]) and Acharya (ACH) methods were included. JBI tool was used to assess the risk of bias. The search detected 9799 studies, out of which 56 were eligible (n=13,107 panoramic radiographs of Indian individuals). Low risk of bias was registered for 48 studies, while 8 presented a moderate risk of bias. The meta-analysis showed a standardized mean difference between chronological and estimated ages of -0.11 (95%CI: -0.29; 0.07), 0.74 (95%CI: 0.39; 1.09), and -0.01 (95%CI: -0.23; 0.22) years for DEM, modified-DEM and ACH, respectively. High heterogeneity (I2=88-93%) was observed across studies for all the methods, including subgroup analyses based on sex. This study ranked ACH, DEM and modified-DEM (from the best to the worse) performances in the Indian population.

Comparing the relative influence of obesity and ancestry on timing of dental development

INTRODUCTION

The dentition is one of the most accurate features for age estimation in children. However, there is some evidence that timing of dental development varies across populations. Recent research suggests that dental development may also be susceptible to influence by environmental factors, such as obesity. Given that there are also population differences in average body mass, it is possible that this may be a confounding variable that was not accounted for in prior work. We aim to compare the relative association between body mass index (BMI) and ancestry with timing of dental development.

METHODS

A retrospective cross-sectional chart review was undertaken using panoramic radiographs of 6- to 12-year-olds (n = 281). Age, ancestry, sex, height, and weight were obtained. Dental development was assessed using the Demirjian method, and chronological age was subtracted from estimated dental age to determine relative timing of dental development (ΔAge). BMI was calculated based upon recorded height/weight within 6 months of time of radiograph.

RESULTS

We found no difference in timing of dental development (accelerated/delayed) across ancestry groups (African-American, Euro-American, Hispanic, Asian; P = .15). Overweight/obese subjects had statistically significantly advanced (precocious) dental development (P < .001). Compared to normal-weight subjects, children who were overweight's age were overestimated by 5.76 months (0.48 years) and children with obesity by 5.97 months (0.49 years) on average.

CONCLUSIONS

BMI appears to have a greater impact on relative timing of dental development than ancestry in this population. Our results support other findings that obesity results in accelerated growth and development.

A Comparative Study of the Assessment of the Accuracy of Willems' and Demirjian's Methods in Dental Age Estimation of the Saudi Arabian Population

BACKGROUND

The notion that "age is just a number" is sometimes expressed colloquially; however, within the domains of medicine and dentistry, age is not only a numerical value. Rather, it has significant importance in several facets of diagnosis and treatment planning. Demonstrating one's identity is necessary not only in the aftermath of natural calamities or mishaps but also in the context of forensic examination of living persons. Age assessment is a very important tool in forensic odontology and plays a vital role in various fields, including medico-legal matters. The primary focus of the current investigation is to assess the precision and correctness of the data and reliability of Demirjian's method (DM) and Willems' method (WM) for age estimation (AE) among the population of Saudi Arabia.

METHODOLOGY

This research was conducted on 300 children from Saudi Arabia, aged seven to 13 years, including both males and females. The assessment of orthopantomography images involved the utilization of both Demirjian's and Willems' methodologies for ascertaining dental age. This determined dental age was then meticulously juxtaposed with the chronological age (CA) of every participant. The data collected underwent a comprehensive statistical analysis, which encompassed the application of the paired t-test.

RESULTS

By using both methodologies, it was discovered that the estimated age (EA) exhibited higher values in both men and females compared to the CA. Both Willems' and Demirjian's approaches yielded significantly different results in terms of statistical significance (p = 0.000 and p = 0.000, respectively), as shown by the comparison.

CONCLUSION

When comparing Willems' technique to Demirjian's method, it was found that the population under research showed somewhat greater accuracy levels for AE. However, it is important to note that the disparity between these two approaches was relatively small. Consequently, it is imperative to emphasize the necessity for additional research involving a larger sample size to establish the validation of a more region-specific AE method tailored specifically for the Saudi Arabian population.

Chronology of permanent teeth mineralization in Brazilian individuals: age estimation tables

BACKGROUND

Age is important in forming the uniqueness of individuals. When chronological age is not available, age estimation is required, particularly in court cases. The mineralization chronology of permanent teeth is a valuable tool for age estimation of subadults. This study aimed to evaluate the mineralization stages of permanent teeth of Brazilian subjects from imaging exams, using the classification by Moorrees et al. modified by the authors, to verify the existence of correlation between the chronology of mineralization stages and sex and to prepare numerical tables of the chronology of dental mineralization stages for Brazilian individuals.

METHODS

Digital panoramic radiographs of 1100 living Brazilian individuals of both sexes, aged between 2 and 25 years, born between 1990 and 2018, from the image bank of a Dental Radiographs and Documentations clinic located in the city of Araraquara, SP, Brazil. The images were evaluated according to the level of crown and root development and classified according to the stages proposed by Moorrees et al. (Am J Phys Anthropol 21: 205-213, 1963) adapted by the authors. All analyses were performed in the R software. Descriptive and exploratory analyses were performed on all data. For intra- and inter-examiner analyses, the rate of agreement and Kappa statistics at a 95% confidence interval were used. Kappa was interpreted according to Landis and Koch.

RESULTS

Only upper and lower canines showed significant differences between the sexes (p < 0.05), with higher average ages for men. The findings were presented in tables, as well as age estimates with 95% confidence intervals for each mineralization stage and each tooth.

CONCLUSION

In the present study, we evaluated the mineralization stages of permanent teeth of Brazilian subjects from digital panoramic radiographs and found no correlation between the chronology of mineralization stages and sex, except for canines. From the obtained results, numerical tables of the chronology of dental mineralization stages were prepared.

Age Estimation in 0-8-Year-Old Children in France: Comparison of One Skeletal and Five Dental Methods

Age estimation in juveniles is a critical procedure in judicial cases for verification of imputability or for civil reasons when adopting children. Several methods based both on skeletal and dental growth have been performed and applied on different populations; nevertheless, few articles have compared different methods in order to test their reliability in different conditions and age ranges, and this is a clear obstacle in the creation of common guidelines for age estimation in the living. A comparison of five dental methods (Anderson, Ubelaker, Schour and Massler, Gustafson and Koch, Demirjian) and one skeletal method (Greulich a Pyle atlas) was performed on a population of 94 children aged between 0 and 8 years. Results showed that, whereas under 2 years all the methods have the same inaccuracy, over 2 years the diagram methods, such as Schour and Massler and Ubelaker's revised one, have a lower error range than the most frequently used Greulich and Pyle atlas and Demirjian method. Schour and Massler, Gustafson and Koch, and Ubelaker methods showed, respectively, a mean error amounting to 0.40, 0.53, and 0.56 years versus the 0.74 and 0.88 years given by Demirjian and the Greulich and Pyle atlas. An in-depth analysis of the potential of several methods is necessary in order to reach a higher adherence of age estimation with the complexity of growth dynamics.

Age estimation of children based on open apex measurement in the developing permanent dentition: an Egyptian formula

Background

Cameriere’s original formula based on open apex measurements is a reliable, clinically applicable method for dental age estimation in different populations children. Dental development may differ between Egyptian children and other ethnic populations which may affect dental age accuracy using Cameriere’s formula.

Aim

Firstly, to verify Cameriere’s original formula on large Egyptian children sample, secondly, to develop an Egyptian-specific formula based on Cameriere’s method.

Material and methods

A prospective cross-sectional study of 762 good quality Orthopantomograms (OPGs) of 5–15 aged healthy Egyptian children selected from Nile Delta governorates between August 2020 and December 2021. Chronological age (CA) was calculated by subtracting birth date from radiograph date. OPGs were analyzed for N0, S, Xi morphologic variables using Sidexis program after that dental age was calculated using Cameriere’s formula then compared to CA. Multiple linear regression model was used to adapt Cameriere’s formula to construct an Egyptian formula. The same sample was used to verify the new formula accuracy.

Results

A total of 1093 OPGs were collected; 762 OPGs which met inclusion criteria were analyzed. Cameriere’s original formula revealed − 0.59- and − 0.53-year underestimation of females and males dental age (DA) respectively (p < 0.001). Regression analysis using the morphologic variables showed that X4, X7, N0 contributed significantly to CA yielding Egyptian-specific formula. New formula showed − 0.12-year male underestimation and 0.1-year female overestimation (p > 0.05).

Conclusion

Egyptian formula was more accurate than Cameriere’s formula in Egyptian children.

Clinical relevance

Egyptian-specific formula decreases the gap between CA and DA, so a relative approximate age is obtained that helps proper diagnosis and treatment planning for orthodontic and pediatric dentistry problems.

Adapting Demirjian Standards for Portuguese and Spanish Children and Adolescents

Estimation of children's chronological age is highly important in human and forensic sciences. The Demirjian method has been reported as accurate for this purpose. The literature review shows some evidence that the accuracy of estimating chronological age via the Demirjian standards is not a straightforward process. The objective of this research is to analyze the reliability of the Demirjian standards in Portuguese and Spanish children and adolescents and adapt it to include sex and group age as contingent factors.

METHODS

Orthopantomographs of 574 Portuguese and Spanish male and female children and adolescents were employed to test the reliability of the Demirjian method. After testing for inter-rater consistency and age estimation using the Demirjian standards, multiple regression analysis was performed controlling for sex and age group.

RESULTS

The Demirjian standards overestimated chronological age for both sexes, mainly for females. Through the development of regression functions, more detailed dental age estimation was performed. The predictive capacities of the Demirjian method and the significant teeth varied as a function of children's age. The Demirjian global standard predicted over 65% of the variance of the chronological age. Taking a tooth-by-tooth approach, the predictive ability increased by over 70%.

CONCLUSIONS

The accuracy of estimating chronological age via the Demirjian method is not as reliable as it might appear, judging from the results found according to age group and according to sex crossed with age group.

Boosting algorithm improves the accuracy of juvenile forensic dental age estimation in southern China population

Age estimation based on the mineralized morphology of teeth is one of the important elements of forensic anthropology. To explore the most suitable age estimation protocol for adolescents in the South China population, 1477 panoramic radiograph images of people aged 2-18 years in the South were collected and staged by the Demirjian mineralization staging method. The dental ages were estimated using the parameters of the Demirjian and Willems. Mathematical optimization and machine learning optimization were also performed in the data processing process in an attempt to obtain a more accurate model. The results show that the Willems method was more accurate in the dental age estimation of the southern China population and the model can be further optimized by reassigning the model through a nonintercept regression method. The machine learning model presented excellent results in terms of the efficacy comparison results with the traditional mathematical model, and the machine learning model under the boosting framework, such as gradient boosting decision tree (GBDT), significantly reduced the error in dental age estimation compared to the traditional mathematical method. This machine learning processing method based on traditional estimation data can effectively reduce the error of dental age estimation while saving arithmetic power. This study demonstrates the effectiveness of the GBDT algorithm in optimizing forensic age estimation models and provides a reference for other regions to use this parameter for age estimation model establishment, and the lightweight nature of machine learning offers the possibility of widespread forensic anthropological age estimation.

Dental age estimation with two different methods in paediatric patients with hypothyroidism

OBJECTIVE

This case-control study aimed to evaluate dental age estimation in children with hypothyroidism using two different methods in order to contribute to the literature about the most accurate method.

DESIGN

In the study, panoramic radiographs of 80 patients with hypothyroidism aged 5-13 years and 80 randomly selected age and sex-matched healthy patients were examined retrospectively. The Cameriere's and the Nolla's methods were used for the dental age estimation. Dental ages and their differences with chronological ages were compared according to group and sex.

RESULTS

No statistically significant difference in estimated dental age was found between the hypothyroidism and control groups using both methods (p > 0.05). Among all the males and females included in this study, the dental ages of the females calculated by Nolla's method were significantly lower than those of the males according to the chronological ages (p < 0.05). For females, in both the hypothyroidism (p < 0.001) and control (p = 0.001) groups, the dental age estimated by Cameriere's method was significantly closer to the chronological age compared to Nolla's method, although there was no statistically significant difference for males.

CONCLUSION

Although the dental age of children with hypothyroidism showed similar results to that of healthy children, it is concluded that Cameriere's method led to more accurate results than Nolla's method in females for both healthy patients and patients with hypothyroidism.

Age Estimation in Children by the Measurement of Open Apices in Teeth: A Study in the Western Indian Population

In forensic sphere and clinical dentistry, age estimation is a topic of utmost importance. Various techniques are employed in children to determine age; however, dental development has proven to be an appropriate method because of its low variability. Cameriere's method is a widely accepted method of age estimation in children, which is carried out by measuring the projections of open apices and also the heights of developing permanent teeth seen on panoramic radiographs. The aim of this study is to establish a new formula for age estimation in the Western Indian population by measuring the open apices of mandibular teeth using Cameriere's European formula. For this study, we included 311 panoramic radiographs of healthy children living in Western India (Maharashtra, Gujarat, and Goa) aged 4–15 years which were analysed by two independent researchers. Seven left permanent mandibular teeth were assessed for length and width of open apices. Dental maturity was evaluated using measurements of the left seven permanent mandibular teeth (x_i = A_i/L_i, i = 1,…, 7), the sum of the normalized open apices (s), and the number (N0) of teeth with complete root formation. A linear relationship between open apices, N0, age, and other factors was evaluated with the aid of a stepwise multiple regression model. A stepwise linear regression showed that all parameters, gender, s, N0, and x₅, were significantly associated with age (R = 85%). No statistically significant difference was found between the predicted and actual chronological age of children in the age group of 4–13 years using the regression equation for the Western Indian population. The present research suggests that the new regression formula developed will be more accurate for age assessment in the Western Indian population.

Concordances and correlations between chronological, dental and bone ages: A retrospective study in French individuals

Bone and dental maturations are subject to physiological, environmental and pathological variables and are unique to each individual. Numerous methods for age estimation appeared to answer a new demand explained by the contemporary migratory movements and the increase of the crime rates. The objective of this study was to observe the relationships between skeletal and dental maturation stages to estimate which methods can be applied to a French population. This retrospective study was based on panoramic and cephalometric radiographs belonging to 192 (101 females and 91 males) orthodontic patients aged between 9 and 19 years, inhabitants of the Provence-Alpes-Côte d'Azur region. The Demirjian method based on dental calcification was used to estimate dental age. For the assessment of skeletal maturity and bone age, the Cervical Vertebral Maturation (CVM) method (Baccetti et al.) and its computerized version (Decocq et al.) were used. Spearman's correlation tests were performed to estimate the correlation between dental calcification stages and those of cervical vertebral maturation among the study population. The methods of Lin's concordance correlation coefficient and Bland and Altman were used to analyze the concordance between bone, dental and chronological ages. A moderate but statistically significant correlation was obtained between dental and skeletal developmental stages (R = 0.383-0.618). The tooth showing the highest correlation with vertebral stages was the second molar for both sexes. Earlier vertebral maturation stage affiliation was observed in girls. The results confirmed that bone and dental maturations can be assessed to estimate relevant biological ages for children in orthodontic or forensic contexts.

A critical test of twelve methods for estimating age using radiographic staging of developing teeth on a sample of 6- to 15-year-old children from Mérida, Yucatán (México)

Cross-population applicability of osteological and dental methods is a known issue in forensic anthropology, but very little is known about whether differences between populations are due to ancestry, environment effects, or even the statistical approach utilized for developing the methods. This study wishes to add to the discussion of population-specificity of dental age estimation methods and examine the impact of their statistical basis on their accuracy and precision. These parameters were estimated by testing 12 different dental age estimation techniques on a sample of 182 panoramic radiographs of children between the ages of 6 and 15 years (110 girls and 72 boys) from the city of Mérida in Yucatán, México. None of the 12 methods selected is based on Mexican samples. Dental maturation was scored following and methods tested employed two dental scoring schemes: Moorrees, Fanning, and Hunt's (MFH) 13-/14-stage system and Demirjian's 8-stage system. Results show that methods derived from more geographically specific groups do not fare better or worse than methods developed on more diverse and inclusive international samples, even if no methods specific to Mexicans were tested. While some of the methods performed very well, and they were not based on a Mexican sample, this suggests that population-specific dental age estimation methods may be relatively unimportant or that population differences in dental maturation are very small. Other issues seemed to have a greater impact on accuracy and precision, such as age dependency, inclusion of the third molar in age assessments, age truncation and age heaping in reference samples, the dental scoring scheme used, and how predicted age is calculated mathematically. As such, findings in this study suggest that validation tests of age estimation methods may not be a useful or reliable means to assess population differences and that these differences need to be more systematically assessed if an argument is to be made for the increased accuracy and precision of population-specific methods. The statistical basis of dental prediction methods seems to have a more significant role in their accuracy and precision outside of their reference sample.

Accuracy of the Demirjian's method for assessing the age in children, from 1973 to 2020. A meta-analysis

One of the most common ways to assess the age in subadults using dental records is the Demirjian method. As the number of the studies using this method increased significantly in the recent years, and as their results were often conflicting, we investigated the accuracy of the method. We performed a systematic review and meta-analysis of observational studies obtained from Pubmed, using a random-effects model with the DerSimonian-Laird estimator, and raw mean difference for effect size measure. Prediction intervals (at 95%) were used to assess the presence of significant statistical differences between chronological and dental age. Our meta-analysis showed that Demirijan's method overestimated dental age by 0.48 years in girls and 0.51 in boys. Depending on the location and sex, in girls the smallest average overestimation was found in Asia (except India), with a value of 0.36 years, and the largest overestimation in Turkey/Arabia, with a value of 0.66 years. In boys, the smallest average overestimation was found in India (0.45 years), but Asia (except India), Africa - both with 0.46 years and Oceania - with 0.47 years were close, while the largest overestimation was found in Turkey/Arabia, with an average value of 0.63 years. The Demirjian method overestimated the age by about half a year for both sexes. Even if there are some geographical/ethnic differences, they are rather small, making the method useful irrespective of the ethnic profile of the subjects.

Dental age in children with impacted maxillary canines

OBJECTIVE

The aim of this study was to evaluate if delayed dental development is a cause of postponed care for patients with impacted maxillary canine (IMC).

MATERIALS AND METHODS

This case-control study was based on 403,355 children and adolescents in Region Västra Götaland, Sweden. The subjects, who were in the age range of 9-16 years during the period of 2011-2013, underwent surgical exposure or removal of a maxillary canine. Demirjian's dental age assessment was carried out on panoramic radiographs.

RESULTS

In total, 1028 patients, 514 with IMC and 514 age- and gender-matched controls, were enrolled. The patients with IMC exhibited a dental development delay of 0.2 years compared to the control group. In the impaction sub-groups, the female patients, patients in the chronological age group of 12-13 years, and patients with palatally positioned IMC had a significantly lower dental age than their paired-control subjects.

CONCLUSIONS

Overall, the difference in dental age between patients with or without IMC is significant but small, and as such is likely of minor clinical relevance. Therefore, the timing of preventive care and treatment for patients with IMC should be the same as that for patients with normally erupting canines.

Age estimation in the living: A scoping review of population data for skeletal and dental methods

Age estimation of living individuals has become a crucial part of the forensic practice, especially due to the global increase in cross-border migration. The low rate of birth registration in many countries, hence of identification documents of migrants, especially in Africa and Asia, highlights the importance of reliable methods for age estimation of living individuals. Despite the fact that a number of skeletal and dental methods for age estimation have been developed, their main limitation is that they are based on specific reference samples and there is still no consensus among researchers on whether these methods can be applied to all populations. Though this issue remains still unsolved, population information at a glance could be useful for forensic practitioners dealing with such issues. This study aims at presenting a scoping review and mapping of the current situation concerning population data for skeletal (hand-wrist and clavicle) and dental methods (teeth eruption and third molar formation) for age estimation in the living. Two hundred studies on the rate of skeletal maturation and four hundred thirty-nine on the rate of dental maturation were found, covering the period from 1952 and 2020 for a total of ninety-eight countries. For most of the western and central African countries there are currently no data on the rate of skeletal and dental maturation. The same applies to the countries of the Middle East, as well as the eastern European countries, especially as regard the skeletal development.

Accuracy of the London atlas, Willems, and Nolla methods for dental age estimation: a cross-sectional study on Eastern Turkish children

OBJECTIVES

This study aimed to estimate the dental age (DA) using the London Atlas, Willems, and Nolla methods and to compare their accuracies.

METHODS

The DA was estimated using the aforementioned methods on panoramic radiograms of a total of 919 Eastern Turkish patients aged 6-14 years, of whom 459 were female and 460 were male. The overestimation and underestimation values were determined in relation to the chronological age (CA) values. The paired t test was used to compare the mean DA and CA values. Multiple regression analysis was used to derive gender-specific formulations for the three methods.

RESULTS

The most accurate method for estimating the DA was the Willems method (mean prediction error 0.80), followed by the London Atlas (mean prediction error 0.83) and Nolla (mean prediction error 0.89) methods. Statistically significant differences were found only between the Willems and Nolla methods.

CONCLUSION

All three methods can be used for DA estimations of Eastern Turkish children.

CLINICAL RELEVANCE

Willems was the most suitable method for this patient sample. However, the London Atlas method may be preferred due to its practicability and comparable accuracy.

A modified dental age assessment method for 5- to 16-year-old eastern Chinese children

Objectives

Age estimation is widely applied in the field of orthodontics, pediatric dentistry, and forensic science. Dental age estimation by the radiological method is frequently used because of its convenience and noninvasiveness. However, there are not enough suitable methods for eastern Chinese children. This study aimed to establish a modified formula for eastern Chinese children according to the Demirjian method and then compared the accuracy of the modified method with the Demirjian method and Willems method.

Materials and methods

A total of 2367 dental panoramic radiographs from individuals aged 5–16 years of eastern China were collected as samples. Age estimation was conducted using the Demirjian and Willems methods. The polynomial curve fitting method was used to modify the Demirjian method to improve its application to the eastern Chinese children. The paired t test and accuracy ratio were used to compare the applicability of the modified methods with two commonly used methods.

Results

The mean chronological age (CA) of the subjects was 11.20 ± 3.29 years for boys and 10.99 ± 3.12 years for girls. The mean difference values between the CA and dental age (DA) (CA–DA) using the Demirjian and Willems methods were 0.73 and 0.7 for boys, respectively, and both 0.79 for girls. The modified method using the polynomial curve fitting presented a smaller underestimation compared with CA for both boys (0.04 years) and girls (0.09 years), which showed a high suitability to Chinese children to some extent.

Conclusions

The Willems method was more accurate in estimating DA compared with the Demirjian method. However, the modified method was more accurate than the two methods; therefore, it can be used in eastern Chinese children.

Clinical relevance

It was thought to be a non-invasive, convenient, and efficient method to connect DA and CA. By estimating dental age, pediatrist, and orthodontists can better understand the development of permanent teeth and provide a more accurate orthodontic treatment time and treatment plan to children patients.

Dental age estimation using Willems method: A cross-sectional study on children in a North Indian city

Background:

Numerous methods of age estimation have been proposed. The Demirjian method which was first applied in a French-Canadian population in 1972 is the most frequently used dental age estimation method. However, a constant over estimation using this method has been reported by numerous researchers. The Willems method is a modification of the above and was first applied in a Belgian Caucasian population in 2002. Several studies in the recent years found Willems method to be more accurate than the original Demirjians method.

Objectives:

The objective of this study was to evaluate the applicability of Willems method for dental age estimation in 6 -15-year-old North Indian children.

Methods:

The sample for this cross sectional study consisted of 390 OPGs of (215 boys and 175 girls) randomly selected from the patient records of a post graduate training dental college in North India. Exact chronological age of the subjects (in years and months) was calculated. The OPGs were used to score the seven mandibular teeth and dental age was estimated using the tables proposed in Willems method.

Results:

Significant correlation between the chronological age and dental age estimated using Willems method was observed in both males (r = 0.90) and females (r = 0.87). The mean difference between estimated DA and CA for males was 0.004 ± 1.08 years (P = 0.94). While for females, it was 0.031 ± 1.18 years (P = 0.72). The results showed no statistically significant difference between chronological age and dental age estimated using Willems method in the study population.

Conclusion:

Willems dental age estimation method without any modification can predict the chronological age of 6-15 year old North Indian children with good accuracy.

Accuracy of the Demirjian, Willems and Nolla methods for dental age estimation in a northern Chinese population

OBJECTIVE

The objective of the present study was to evaluate the accuracy of the Demirjian, Willems, and Nolla methods for dental age estimation on a sample of the northern Chinese population.

DESIGN

The study consisted of 2000 panoramic radiographs (1000 boys and 1000 girls) with an age range between 5 and 14 years. The mean error and absolute mean error were calculated according to each method, and the accuracy was statistically analysed.

RESULTS

The three methods used for Chinese subjects overestimated the dental age by 1.16, 0.50, and 0.07 years. The absolute mean error was largest in most age groups for the Demirjian method, which was considered inaccurate in age estimation for teenagers, and it was more than 1.00 years for only several age groups for the Willems method and only girls aged 14 years for the Nolla method. The mean error and absolute mean error were lowest for the Nolla method and highest for the Demirjian method.

CONCLUSIONS

Although the Demirjian method is frequently used in Chinese subjects for legal and medical purposes, the Willems and Nolla methods were more reliable than the Demirjian method. Among the three methods, the accuracy in the northern Chinese subjects was highest for the Nolla method. Therefore, it is recommended to evaluate the accuracy of different methods before assessing the age in specific populations.

Deep Neural Networks for Chronological Age Estimation From OPG Images

Chronological age estimation is crucial labour in many clinical procedures, where the teeth have proven to be one of the best estimators. Although some methods to estimate the age from tooth measurements in orthopantomogram (OPG) images have been developed, they rely on time-consuming manual processes whose results are affected by the observer subjectivity. Furthermore, all those approaches have been tested only on OPG image sets of good radiological quality without any conditioning dental characteristic. In this work, two fully automatic methods to estimate the chronological age of a subject from the OPG image are proposed. The first (DANet) consists of a sequential Convolutional Neural Network (CNN) path to predict the age, while the second (DASNet) adds a second CNN path to predict the sex and uses sex-specific features with the aim of improving the age prediction performance. Both methods were tested on a set of 2289 OPG images of subjects from 4.5 to 89.2 years old, where both bad radiological quality images and images showing conditioning dental characteristics were not discarded. The results showed that the DASNet outperforms the DANet in every aspect, reducing the median Error (E) and the median Absolute Error (AE) by about 4 months in the entire database. When evaluating the DASNet in the reduced datasets, the AE values decrease as the real age of the subjects decreases, until reaching a median of about 8 months in the subjects younger than 15. The DASNet method was also compared to the state-of-the-art manual age estimation methods, showing significantly less over- or under-estimation problems. Consequently, we conclude that the DASNet can be used to automatically predict the chronological age of a subject accurately, especially in young subjects with developing dentitions.

A Comparative Evaluation of Three Different Dental Age Estimation Methods in India: A Test of Ethnic Variability

Aim

The present study aimed to evaluate and compare the applicability of Demirjian, Willems, and Haavikko methods of dental age estimation in southeastern (Dravidian ethnicity) and northwestern regions (Aryan ethnicity) of the Indian population.

Materials and methods

The study includes the orthopantomographs (OPGs) of 303 individuals (173 males and 130 females) of age ranging from 5 to 14 years. The participants in the present research were evaluated under two study groups: group I: participants of the southeastern region and group II: participants of the northwestern region. Dental age was calculated using Demirjian, Willems, and Haavikko methods and compared with the chronologic age of each participant. The accuracy of dental age estimation methods was evaluated by mean absolute error. One-way analysis of variance (ANOVA) and Student's t tests were used to test the significant difference between the chronologic age and estimated dental ages.

Results

The Demirjian method showed overestimation, while Willems and Haavikko methods showed underestimation for boys and girls in both the ethnic groups of Indian population. The Willems method of dental age estimation showed comparatively more accurate and reliable results in both the ethnic groups of the Indian population.

Conclusion

The dental age estimation by Demirjian, Willems, and Haavikko methods showed no significant variation between the different ethnicities of the Indian population.

Clinical significance

The present research will be helpful in pedodontic, orthodontic, and forensic investigations for accurate and reliable dental age estimation in different parts of Indian population.

How to cite this article

Chaudhry K, Talwar M, Vanga NRV, et al. A Comparative Evaluation of Three Different Dental Age Estimation Methods in India: A Test of Ethnic Variability. Int J Clin Pediatr Dent 2020;13(1):16–20.

Relationship between dental calcification of mandibular teeth and cervical vertebrae maturity in patients with unilateral complete cleft lip and palate

OBJECTIVE

The purpose of this study was to investigate the relationship between the dental calcification stage (DCS) of the mandibular teeth and the cervical vertebral maturation stage (CVMS) in patients with unilateral complete cleft lip and palate (UCLP).

METHODS

One hundred sixty-two UCLP patients (100 males and 62 females) between 8-16 years old were included in this study. The DCS was estimated by the Demirjian method and was converted to the dental age (DA). The CVMS was evaluated by the Baccetti method. The DA of mandibular teeth on two sides of the cleft were analyzed using a t-test. Spearman correlation was used to study the association between CVMS and DCS. The correlation coefficient between the two sides of the cleft was then compared.

RESULTS

The total DA was significantly smaller on the cleft side than on the noncleft side in males (p = 0.022). The Spearman rank correlation coefficient revealed a significant correlation between the DCS of each examined tooth and the CVMS (r = 0.627-0.793 in males and r = 0.806-0.899 in females). Additionally, the correlation of the two sides was not significantly different (p > 0.05). The DCS of the first premolar showed the strongest correlation with the CVMS.

CONCLUSION

The results confirm the utility of the DCS on both sides of the mandible in male UCLP patients as a simple first-level diagnostic test to evaluate growth and development. The findings also indicate that both the DCS and the CVMS should be assessed if the maturity stage of a growing UCLP patient is relevant to clinical practice.

Age estimation of Brazilian individuals using the London Atlas

OBJECTIVE

The objective of the present study was to evaluate, for the first time, the applicability of the London Atlas method for age estimation on a sample of Brazilian population.

DESIGN

The study consisted of archived dental panoramic radiographs (n = 288) of individuals aged between 5 and 23 years. Radiographs were assessed using the London Atlas method to determine the developmental and eruption stages of all teeth on each sides of each jaw separately, and also to make an age estimation.

RESULTS

There was no significant differences between the right and left sides of the jaws (p = 0.31 for males and p = 0.65 for females). An overestimation of age occurred more likely in the female sample when compared to the male sample. Three age groups, 20.5, 18.5 and 19.5 years, presented the highest values ​​of mean absolute difference found in the whole sample.

CONCLUSION

The London Atlas of age estimation performed well in general and good viability in an expert context, with most age groups showing age differences lower than two years of age, however it is necessary that it be applied with caution in certain age groups, especially when the third molar is used as a decision tooth for age estimation. Therefore, it is recommended to use more than one method for assessing the age in those age groups.

The applicability of Willems dental age estimation method for Indonesian children population in Surabaya

Background

The applicability of dental age estimation has been expanded to meet a variety of medico-legal needs, law enforcement, and disaster victim identification. The objective of this study is to examine the applicability of the Willems method for Indonesian children.

Material and method

A total of 110 panoramic radiographs of the patients (6–14 years old) who met the inclusion criteria were obtained from the Department of Forensic Odontology and Department of Radiology, Universitas Airlangga, Indonesia. Estimated dental age (EDA) was assessed using the Willems method by two blinded examiners. The statistical analysis was carried out using IBM® SPSS® Statistics version 23.0 (IBM, Armonk, NY, USA).

Results and discussion

The mean of the chronological age (CA) in this study is 11.30 ± 1.43 years (boys) and 11.65 ± 1.55 years (girls). The overall mean difference between CA and EDA for boys and girls is − 0.08 ± 0.76 and − 0.31 ± 0.97, respectively. This study showed that the mean age difference in girls was more significant than in boys. The growth spurt timing between boys and girls might cause a difference in dental maturation, whereas the onset of the pubertal growth spurt in girls is about 2 years earlier than in boys. In general, girls start and finish their dental development earlier than boys end.

Conclusion

The present study suggests that the dental age estimation methods proposed by Willems can be considered as an applicable method for the children population in Surabaya, both boys and girls. However, a detailed study may be required while applying this approach to the 11–14-year-old girl population in Surabaya, as a substantial underestimation was observed in this community.

Age determination in children by orthopantomograph and lateral cephalogram: A comparative digital study

BACKGROUND AND AIMS

The assessment of age is useful in forensic medicine and forensic odontology and in treatment planning in various branch of dentistry. The aim of study is comparative evaluation and assessment of applicability of Demirjian's method, Willem's method of dental age (DA) estimation, and Maria de Paula Caldas's method of skeletal age estimation for children aged 9-16 years.

MATERIALS AND METHODS

A total of 140 individuals (70 females and 70 males) between the age group of 9-16 years were enrolled. These individuals were grouped by a difference of 1 year into 7 groups (each group comprising of 20 individuals: 10 males and 10 females). Dental age estimation was performed from orthopantomograph images of mandibular teeth of left quadrant by both Demirjian's and Willem's methods. Skeletal age estimation was done from Lateral Cephalogram by Caldas Digital Method. The differences between the chronological age and the estimated dental and skeletal ages were statistically tested using paired t-test.

RESULTS

Demirjian's DA estimation overestimated males (0.4040 years) and females (0.1316 years). Willem's DA estimation method underestimated males (0.1386 years) and females (0.4210 years) and Caldas skeletal age estimation overestimated males (0.2982 years) and females (0.4259 years).

CONCLUSION

The study concluded Willem's DA estimation method was the most accurate for male and Demirjian's method for female for Gujarati Population. Caldas's new computer-assisted method for skeletal age estimation used in the present study is easy to perform and less time-consuming and objective method and can be applied for Gujarati population.

Age estimation and comparison by dental and skeletal maturity in the age range of 9-18 years in the Mumbai region

Background:

Age estimation is crucial in the identification of juveniles in conflicts with law, survivor of sexual assault, sportsperson, and civil cases.

Aims:

To estimate and compare the age (9–18 years) by dental and skeletal maturity in the Mumbai region.

Settings and Design:

This was a cross-sectional study.

Materials and Methods:

A total of 70 cases from 9 to 18 years of age were studied in 1 year in the urban population of the Mumbai region. Among 70 cases, 45 were males and 25 were females. Orthopantomogram and elbow joint radiographs were taken to assess the dental age through modified Demirjian's method and the radiological age through Sangma et al. staging method, respectively.

Statistical Analysis:

Data were analyzed using SPSS Statistics Version 26; descriptive statistics and regression statistics were used in the study.

Results:

Dental age by Demirjian's method in males with standard deviation was 15.25 (2.17), with a mean difference of 1.08 and significant P = 0.03. However, in females, dental age by Demirjian's method with standard deviation was 14.30 (1.94) with a mean difference of 0.74 and insignificant P = 0.07. Interclass correlation coefficient of dental age with chronological age, in males and females, showed 0.85 and 0.87 correlation, respectively. Correlation between the skeletal maturity and the dental age was reflected by the association of Demirjian stage 9 in the second molar with radiological stage 5 in males and stage 4 in females.

Conclusions:

It was concluded that Demirjian's method shows a significant correlation and P value for the age estimation in males of the Mumbai region.

Accuracy of Demirjian's and Indian-specific formulae in age estimation using eight-teeth method in Kanyakumari population

Background

Most of the scientific formulae for age estimation in forensic odontology were tested among western population and hence cannot be applied to the Indian population consistently. Therefore, it was in this context that Dr. Ashith B. Acharya had carried out a study using the modified Demirjian's method in Indian population and found out that the study gave inferior results for age estimation. So he developed Indian-specific regression analysis and worked out a formula.

Aim

This study was done to validate age using Demirjian's eight-teeth method and to compare the effectiveness of Demirjian's formula and Indian-specific formula in Kanyakumari population.

Material and Methods

Digital orthopantomographs of 150 patients fulfilling the inclusion and exclusion criteria in the age group of 8-24 years were used in the study. The third quadrant in the radiograph was assessed visually from mandibular central incisor to the third molar using Demirjian's modified criteria chart. Calculation of the dental age was done using Demirjian's formula and Ashith B. Acharya's Indian-specific formula. The difference between chronological age and dental age was calculated, and the mean absolute error (MAE) was obtained.

Results

The MAE was 0.20 years for the whole of Kanyakumari population, and for males it was 0.10 years and for females 0.29 years with Indian-specific formula, whereas the MAE was 2.66, 1.86, and 3.51 years, respectively, for the whole of Kanyakumari population, males, and females using Demirjian's formula.

Conclusion

The observations from this study suggest that the MAE was less between chronological age and estimated dental age which was calculated using Indian-specific formula, compared with the values obtained using Demirjian's formula. Thereby we conclude that Indian-specific formula is more reliable in age estimation of Kanyakumari population.

Dental age assessment of 3-15-year-old Saudi children and adolescents using Demirjian's method-A radiographic study

Dental age assessment plays a pivotal role in clinical practice, demographic studies, forensics, and courts of law but is affected by ethnic and geographic variations. The aim was to determine the population-specific weighted scores needed when dental age is estimated using Demirjian's method for Saudi children and adolescents between the ages of 3 and 15 years. Design: A total of 298 panoramic radiographs were collected from Saudi Arabia. Dental age was assessed using Demirjian's method (1973). Chronological age was determined from the date of birth and the date on which the panoramic radiograph was taken for each individual. Between 3- and 15-years age group, the Saudi boys had an estimated age of 9.07 ± 1.96 years and chronological age of 8.49 ± 2.30 years. The Saudi girls had an estimated age of 9.22 ± 1.93 years and chronological age of 8.78 ± 2.32 years. With Demirjian's method, the Saudi boys were 0.57 ± 1.48 years, and girls were 0.44 ± 1.66 years ahead of their chronological ages (p < .05). New population-specific weighted scores were developed to convert dental age according to Demirjian's method into estimated ages in the contemporary Saudi Arabian population. This study can be used for further research and comparisons with other population groups, regions or communities.

Evaluation of the accuracy of Demirjian's method for estimating chronological age from dental age in Shiraz, Iran: Using geometric morphometrics method

Knowing the growth and developmental stages of a child or an adolescent allows for a comparison between their developmental and chronological age. The purpose of this study was to evaluate the accuracy of dental age estimation by Demirjian's method and to examine the applicability of Demirjian's method to Iranian children and adolescents. To do so, we investigated the relationship between chronological and dental age in a total of 158 children (81 female and 77 male) from Shiraz. The present study, for the first time, employs geometric morphometrics, a relatively new technique, to offer an accurate quantitative assessment of Demirjian's method. The correlation coefficient between chronological and dental age showed a significant relationship between dental age and chronological age. The average of the chronological age difference between girls and boys at the time of reaching the same stages of dental development was 0.77 years, which meant girls reached each stage of dental development 9 months earlier than their male peers. According to the results of this study, although the use of Demirjian's method in estimating the age of children in the city of Shiraz has acceptable accuracy, more precise studies are recommended to calibrate the method and develop a table adjusted to reflect development in the Iranian population.

Applicability of Cameriere European formula for age estimation of 10-15 years legal threshold in South Indian population

AIM

The aim of the present study is to assess the relationship between chronological age (CA) and the measurement of the open apices in teeth and also assess the accuracy of Cameriere methods on dental age (DA) estimation in the South Indian population.

SUBJECTS AND METHODS

A sample of 200 orthopantomographs of children aged between 10 and 15 years were collected. The seven left permanent mandibular teeth were evaluated with Cameriere method.

RESULTS

Regression analysis was carried out which derived the following linear regression formula: Age = 14.117 - 0.01 g - 1.732W3 + 0.016N0 - 0.289 × 5 - 0.099.s. N0. The equation explained 88.3% (R 2 = 0.883) of the total deviance. The accuracy of the European formula and South Indian formula was determined by the difference between the estimated DA and CA. Cameriere formula produced 32% and 18% of absolute residuals falls within the range of ± 1 and ± 0.5 years, whereas the new regression formula produced 72% and 35% within range of ± 1 and ± 0.5 years.

CONCLUSION

This further highlight the importance of population-specific formula keeping in mind about variation in dental maturation across different regions.

Predictive accuracy of Demirjian's, Modified Demirjian's and India specific dental age estimation methods in Odisha (Eastern Indian) population

This study is aimed at finding the predictive accuracy of Demirjian's (D), modified Demirjian's (MD) and India specific age estimation methods (AA) Indian specific age estimation methods in 522 healthy children of Odisha population among 3-18 years. Correlations between chronological age (CA) and derived age (DA) by above mentioned methods were evaluated by Wilcoxon signed rank test and Pearson's correlation analysis. Analysis of mean absolute error concluded that D and MD predicted the CA with fair accuracy, whereas, AA had lower accuracy in Odisha children. Odisha specific polynomial regression formula, derived in this study is showing a strong correlation with CA (r=0.84). Comparison of mean absolute error of D, MD, AA and Odisha specific method indicated a better predictive accuracy of Odisha specific method.

Applicability of Demirjian's method for dental age estimation in a group of Egyptian children

Aims

The aims of this study were to evaluate the applicability of Demirjian’s method for dental age assessment in a group of Egyptian children in Minia city and to develop an age predictive equation suitable for the studied group.

Subjects and methods

In this retrospective, blind, cross-sectional study, 160 dental panoramic radiographs (DPTs) were selected from 420 DPTs from healthy children aged between three and 10 years old from the archived medical files of patients attending Minia University Dental Hospital (MUDH) and evaluated to estimate dental ages.

Results

Age was overestimated for almost all of the studied subjects with an accuracy range from 0.18 to 1.19 years for males and from 0.08 to 0.87 years for females, with the exception of two age subgroups (9–10-year-old males and 10–11-year-old females, for which the mean difference values were −0.06 and −0.008 years, respectively). A Logistic regression was used to generate a suggested formula for dental age estimation.

Conclusions

Demirjian’s method may be unsuitable for Egyptian children living in Minia city. Development of a predication equation and the introduction of adaptable conversion tables to transform the maturity score into a dental age for Egyptian children may be suitable alternatives. The validity of the newly developed prediction equation must be tested among all Egyptian children.

Dental age estimation using radiographs: Towards the best method for Sri Lankan children

Research supports the need for regionally and ethnically specific validated data as the reference base for age estimation techniques. This retrospective study evaluated the accuracy of three dental age estimation methods; Demirjian et al. (1973), Willems et al. (2001), and Blenkin and Evans (2010), for use in Sri Lanka for medico-legal purposes. Panoramic radiographs of 688 Sri Lankan children ranging in age from 8.00 to 16.99 years were used to determine their appropriateness to a Sri Lankan population. The mean age and standard deviations (±SD) were calculated separately for males and females of each age group. Paired t-test and mean absolute errors (MAE) were calculated to compare the calculated dental age (DA) with the chronological age (CA) across the nine age groups. The results revealed the mean CA of the entire sample was 12.38 ± 2.68 years, while the mean DA calculated using the Blenkin and Evans method was 11.83 ± 2.20 years, using the Demirjian et al. method was 12.57 ± 2.53 years, and using the Willems et al. method was 11.99 ± 2.43 years. The Demirjian et al. method consistently overestimated the age of males except in the 2 groups aged over 15 years, whereas the Blenkin and Evans method consistently underestimated the age except for the 11.00-12.99 age range. The method of Willems et al. produced DA quite close to CA up until 12.99 years of age, and then underestimated the age for all higher age groups. In females, the Demirjian et al. method consistently overestimated the age up until 13.99 years and then underestimated the higher age groups, while the Willems et al. method underestimated the age in all age groups except 10.00-10.99 years. The Blenkin and Evans method also consistently underestimated the age except in the 10.00-10.99 and 12.00-12.99-year age groups. The percentages of either overestimation or underestimation calculated for ±0.5 years of the true age were 41.0% for the Blenkin and Evans method, 42.8% for the Demirjian et al. method and 49.1% for the Willems et al. method. In conclusion, while all three methods could be applicable in the estimation of dental age for medico-legal purposes, the Willems et al. method appears to be more appropriate in overall measures for the Sri Lankan reference sample, up to the age of 12.99 years.

The development and status of forensic anthropology in India: A review of the literature and future directions

Forensic anthropology deals with the identification of human remains in a legal setting. The primary role of a forensic anthropologist is to evaluate human skeletal remains and ascertain the biological profile of the deceased. Forensic anthropologists thus use their expertise to assist medical examiners, as well as law enforcement agencies. Forensic anthropology was not recognised as a subject specialty of much significance in most parts of the world for a long time. However, now its status has changed, mostly in the USA and parts of Europe. The scope of the subject ranges from evaluation of human skeletal remains to the identification of the living. In the new millennium, the role of forensic anthropologists includes disaster victim identification, photographic superimposition, facial image reconstruction in CCTV footage, gait pattern analysis from video surveillance, ascertaining the age of an individual in absence of legal documents and paedo-pornographic materials. Despite its relevance in human identification, the development of forensic anthropology in India is not very encouraging. Only a few institutions in India include forensic anthropology as a part of the forensic science degree programme, and there are no certified courses in anthropology either. Likewise, there are limited employment opportunities for forensic anthropologists in medical institutes/organisations/universities. This comprehensive review focuses on the status and development of forensic anthropology in India and emphasises the need for its recognition as a specialty of significance. The article also throws light on the comparison of its status in the Indian context vis a vis developed nations.

Accuracy of age estimation in 6-21 year old South Indian population - A comparative analysis of clinical and radiographic methods

Unavailability of chronological age brings to the forefront the importance of age estimation for human identification. Dental age is routinely assessed based on the calcification stages and/or the eruption of teeth, which exhibit wide variations amongst different ethnic groups. The current study aimed at estimating the dental ages in 384 South Indian subjects aged 6-21 years, using clinical and radiographic methods and comparing the predictive accuracy of these two dental age estimation methods. For the estimation of age by clinical method, Foti and co-workers' mathematical Model 2 was employed and for the radiographic method, Chaillet and Demirjian's method with Acharya's Indian formula was used. The clinical method yielded a mean error in the range of -3.16 to 4.07 years and -1.83 to 4.32 years among male and female subjects respectively whereas the radiographic method yielded an error of -9.52 to 1.96 years among males and an error of -10.72 to 2.66 years in females. The mean absolute error for the entire sample obtained by clinical method was 0.80 years and by radiographic method was 0.89 years. We found that the clinical method had a better accuracy in estimating dental age of children and adolescents when compared to the radiographic method in South Indian (Karnataka) population. However, the difference between the two is negligible implying that either of the methods can be employed in clinical practice.

Assessment of Skeletal Age Using Hand-Wrist Radiographs following Bjork System

The knowledge of the skeletal maturation and the stage of the growth of the patients seeking orthodontic treatment are of great value in planning efficient orthodontic therapy. However, different craniofacial structures of patient show variation in growth potential. The routine use of hand-wrist radiograph for growth prediction exposes the patient to extra radiation. Cervical vertebrae in the lateral cephalograph have been recommended as an alternative method. The pubertal growth spurt is a vital period in the orthodontic treatment and should be kept in mind when planning orthodontic treatment in growing children. One of the main objectives of taking hand and wrist radiograph is to determine the amount of growth and get used of it in patients with skeletal discrepancy during adolescence. Further, this will help in the selection of the appliances required, the course of the treatment and the retention after active orthodontic therapy.

Dental age estimation using four Demirjian's, Chaillet's and Willems' methods in Kosovar children

BACKGROUND

Tooth formation was recognized as useful body system to assess maturity and predict age. Tooth mineralization is much less affected by the endocrine and different nutritional status than bone mineralization, and teeth formation provides a more reliable indication of chronological age. Demirjian et al. in 1973 presented a scoring system and method for dental age estimation on a sample of French-Canadian children. Chaillet et al. and Willems et al. modified original Demirjian method. This study aimed to evaluate the accuracy of four Demirjian's, Chaillet and Willems methods for age estimation in the children of Kosovo.

MATERIALS AND METHODS

The cross-sectional study was based on the evaluation of the sample of 1022 orthopantomograms (OPTs) of healthy Kosovar children, aged between 5 and 14 years. OPTs were taken from the Radiology unit of University Dentistry Clinical Center of Kosova, as part of random clinical treatment. We tested the accuracy of four methods based on seven mandibular teeth, Demirjian from 1973 (Dem73) and 1976 (Dem76), Chaillet from 2005 (Chaillet) and Willems from 2001 (Willems) and two Demirjian's methods based on different sets of four teeth (Dem76PM1 and Dem76IN2).

RESULTS

For most tested methods, we found statistically significant differences between the chronological age (CA) and dental age (DA) (p < 0.05). In males, the most accurate method were those using four teeth, Dem76IN2 (0.03 years) following by Dem76PM1 (-0.05 years), following those using seven teeth, Willems (-0.14 years), Chaillet (-0.24 years) and Dem73 (0.43 years). In females, dental age was the most accurate for the Willems method (-0.24 years) following Chaillet (-0.35 years), Dem76 (0.43 years) and Dem73 (0.55 years), while Dem76PM1 and Dem76IN2 overestimated by 0.45 years and 0.46 years, respectively. The mean absolute difference between DA and CA were between 0.61 years for the Willems, to 0.78 years for the Dem73 in males, and 0.64 years for the Willems to 0.75 years for the Dem76IN2 in females.

CONCLUSION

The Willems method was the most accurate for estimating a dental age if all seven mandibular teeth are available for analysis, and we found the similar accuracy of Dem76PM1 and Dem76IN2 methods. Therefore, we may encourage their use for age estimation on the Kosovar children.