Dental age assessment: Which is the most applicable method?

Accuracy of second and third molar maturity indices, Olze, Haavikko, and Demirjian methods for 14- and 16-year-old age thresholds assessment in Croatian children and adolescents

This study explores the reliability of four established legal age threshold estimation approaches in a Croatian sample. We applied Haavikko stages, Demirjian stages, Olze's third molar eruption stages, and second and third molar maturity indices measurement in 593 orthopantomograms of Croatian children and adolescents aged 11.00-20.99 years old. The left mandibular second and third molar were assessed. Logistic regression analysis was conducted to test the significance of predictive variables. Logistic Receiver operating characteristic (ROC) curves were performed to evaluate the classification ability of variables for estimating 14- and 16-year-old thresholds. The areas under the ROC curve (AUC), accuracy (Acc), sensitivity (Se), specificity (Sp), Positive Likelihood Ratio (LR +), Negative Likelihood Ratio (LR-), and Bayes post-test probability (Bayes PTP) were calculated to evaluate classification performance. Results suggest that the combination of I2M&I3M is the best classifier for the 14-year-old threshold (AUC = 0.879); for males alone, I2M is an even better classifier (AUC = 0.881). The highest Acc 80.1% (95%CI, 75.9%-83.9%), Bayes PTP 86.5% (95%CI, 82.8%-89.7%) and Sp 88.9% (95%CI, 83.0%-93.3%) were by I3M < 0.81 & I2M < 0.03 in total samples; the highest Acc 86.1% (80.6%- 90.6%), Bayes PTP 87.2% (95%CI, 81.7%- 91.4%) and Sp 87.8% (95%CI, 78.2%- 94.3%) were by I2M < 0.01 in males, Acc of Haavikko Ac and Demirjian H stage in second molar is very close with slightly lower Bayes PTP and Sp. I3M is a good classifier for 16-year-old threshold (AUC = 0.889). The cut-off value I3M < 0.34 can be used to classify the 16-year-old threshold with Acc of 80.6% (95%CI, 77.2%-83.7%), Sp of 83.4% (95%CI, 79.0%-87.3%), and 81.7% (95%CI, 78.4%-84.8%) Bayes PTP. In conclusion, to classify the 14-year-old threshold, a pair of cut-off values I3M < 0.81 & I2M < 0.03 can be used in Croatian females; I2M < 0.01, Demirjian H stage, Haavikko Ac stage in second molar, and the pair I3M < 0.81 & I2M < 0.03 can all be used in Croatian males. I3M < 0.34 can classify the 16-year-old threshold in Croatian populations.

Technical note: RP Atlas-an unprecedented proposal for a Brazilian population dental development chart based on the London atlas

Age estimation methods through developmental atlases are simplified by image comparison using radiographs. Atlas-based methods have been utilized to create population-specific charts addressing population diversity. To tackle the absence of a dedicated atlas for the Brazilian population, the objective of the present study was to create a new atlas for dental development in Brazil based on the London Atlas chart. The new atlas (RP Atlas) is based on the median of tooth development, eruption, and resorption in individuals aged 5 to 23. The sample (567 individuals) was divided between females (n = 290) and males (n = 277). The RP Atlas was handcrafted, scanned, colored, and clustered in two atlases divided by sex. The development of a specific atlas for the Brazilian population has the potential to enhance the accuracy of age estimation in forensic scenarios, notably in a mixed country like Brazil. Further research is needed to assess the suitability of the newly developed atlas for the Brazilian population.

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.

Investigating the association between dental age and polymorphisms in genes encoding estrogen receptors

BACKGROUND

Genetic polymorphisms have been shown to influence several physiological traits, including dental and craniofacial characteristics. Understanding the clinical relevance of genetic polymorphisms in dental practice is crucial to personalize treatment plans and improve treatment outcomes.

OBJECTIVE

to evaluate the association between dental age and genetic polymorphisms in genes encoding estrogen receptors alpha and beta (ESR1 and ESR2, respectively) in a sample of Brazilian children.

METHODOLOGY

This retrospective cross-sectional study was performed with children undergoing orthodontic treatment. Patients with syndromes, congenital anomalies, craniofacial deformities, under hormonal or systemic treatment, and with a previous history of facial trauma were excluded. Panoramic radiographs were used to assess dental age according to the Demirjian, Goldstein, and Tanner method. A delta [dental age-chronological age (DA-CA)] was obtained, which shows whether the patient tends to have a normal, delayed (negative values), or advanced (positive values) dental age. DNA isolated from buccal cells was used to genotype four genetic polymorphisms: rs9340799 (A>G) and rs2234693 (C>T), located in ESR1; and rs1256049 (C>T) and rs4986938 (C>T), located in ESR2. A statistical analysis was performed and values of p<0.05 indicated statistical difference.

RESULTS

A total of 79 patients were included, 44 (55.70%) girls and 35 (44.30%) boys. The Demirjian, Goldstein, and Tanner method, in general, overestimated patients' age by 0.75 years. There was no difference in the delta of dental age between the sexes (p>0.05). Genetic polymorphisms in ESR1 and ESR2 were not associated with dental age (p>0.05).

CONCLUSION

The studied genetic polymorphisms in ESR1 and ESR2 were not associated with dental age in Brazilian children.

A systematic overview of dental methods for age assessment in living individuals: from traditional to artificial intelligence-based approaches

Dental radiographies have been used for many decades for estimating the chronological age, with a view to forensic identification, migration flow control, or assessment of dental development, among others. This study aims to analyse the current application of chronological age estimation methods from dental X-ray images in the last 6 years, involving a search for works in the Scopus and PubMed databases. Exclusion criteria were applied to discard off-topic studies and experiments which are not compliant with a minimum quality standard. The studies were grouped according to the applied methodology, the estimation target, and the age cohort used to evaluate the estimation performance. A set of performance metrics was used to ensure good comparability between the different proposed methodologies. A total of 613 unique studies were retrieved, of which 286 were selected according to the inclusion criteria. Notable tendencies to overestimation and underestimation were observed in some manual approaches for numeric age estimation, being especially notable in the case of Demirjian (overestimation) and Cameriere (underestimation). On the other hand, the automatic approaches based on deep learning techniques are scarcer, with only 17 studies published in this regard, but they showed a more balanced behaviour, with no tendency to overestimation or underestimation. From the analysis of the results, it can be concluded that traditional methods have been evaluated in a wide variety of population samples, ensuring good applicability in different ethnicities. On the other hand, fully automated methods were a turning point in terms of performance, cost, and adaptability to new populations.

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.

Efficacy of machine learning assisted dental age assessment in local population

INTRODUCTION

Although the dental age assessment is commonly applied in forensic and maturity evaluation, the long-standing dilemma from population differences has limited its application.

OBJECTIVES

This study aimed to verify the efficacy of the machine learning (ML) to build up the dental age standard of a local population.

METHODS

We retrospectively studied 2052 panoramic films retrieved from healthy Taiwanese children aged 2.6-17.7 years with comparable sizes in each age-group. The recently reported Han population-based standard (H method) served as the control condition. To develop and validate ML models, random divisions of the sample in an 80%-20% ratio repeated 20 times. The model performances were compared with the H method, Demirjian's method, and Willems's method.

RESULTS

The ML-assisted models provided more accurate age prediction than those non-ML-assisted methods. The range of errors was effectively reduced to less than one per year in the ML models. Furthermore, the consistent agreements among the age groups from preschool to adolescence were reported for the first time. The Gaussian process regression was the best ML model; of the non-ML modalities, the H method was the most efficacious, followed by the Demirjian's method and Willems's methods.

CONCLUSION

The ML-assisted dental age assessment is helpful to provide customized standards to a local population with more accurate estimations in preschool and adolescent age groups than do studied conventional methods. In addition, the earlier complete tooth developments were also observed in present study. To construct more reliable dental maturity models in the future, additional environment-related factors should be taken into account.

Validity of nolla's method for age estimation for children in Kurdish Iraqi population - A retrospective study

Context

Radiographs have an essential role in Chronological Age (CA) estimation and are being used for dental age (DA) determination.

Aims

Detecting the validity of Nolla's method (NM) for the age assessment of Kurdish Iraqi children (KIC).

Methods and Material

A retrospective study was performed using orthopantomographs (OPGs) of 354 subjects aged from 4 to 13 years (178 boys and 176 girls) and their recording files. Subjects were divided into nine study groups: 4, 5, 6, 7, 8, 9, 10, 11, 12, and 13 years old. The chronological age (CA) was subtracted from the DA to find the validity of NM; the positive results indicated the overestimation of age, whereas the negative results indicated for underestimation. The data were recorded through a digitalised system using Microsoft Excel worksheet and analysed by Statistical Package for the Social Sciences (SPSS, version 25) programme using the dependent T-test and graphical analysis. The level of P value used in this study was set at < 0.05. Results: The DA is underestimated in ages 9 to 13 in boys and girls. The highest difference in DA-CA was at the age of 9 years (-0.146 ± 0.162).

Conclusions

NM for age estimation was slightly overestimated in age groups of 4, 5, 6, 7, and 8 years in boys and girls without statistically significant differences. However, this method underestimated the ages of KIC ranging from 9 to 13 years significantly.

Application of the ratio of the radiopaque calcified area to the dental follicle (RCA/DF) for dental age assessment on orthopantomograms

OBJECTIVES

This study aimed at exploring a new tooth development evaluation method for age assessment and investigating the dynamic alteration and potential trend of tooth development by orthopantomograms (OPGs), in order to provide references for tooth development prediction and forensic purpose.

MATERIALS AND METHODS

A total of 132 OPGs of children aged 3-8 years were collected. The developmental stages of the permanent mandibular second molar (M2)were evaluated by experienced examiners according to the Nolla method and Mimics software, respectively. Quantitative analysis of the ratio of the radiopaque calcified area to the dental follicle (RCA/DF) in different stages, ages, sexes and quadrants were evaluated and compared via descriptive statistics and Spearman's correlation coefficient analysis.

RESULTS

There was a strong, positive correlation between the examiners' evaluation and mimics analysis results. With the age increased, the Nolla stage of M2 observed by OPGs increased, and the RCA/DF showed increased trends both in males and females. There were significant differences of the RCA/DF of the M2 at various ages. The tooth calcification development of female was 9.08% earlier than that of male between 3 and 8 years old. However, teeth of male seemed to develop faster than that of female during this period. There was no significant difference between left and right quadrant either according to the Nolla stage or RCA/DF.

CONCLUSIONS

The RCA/DF value obtained from OPGs of the developmental mandibular second permanent molars could be used as a reliable indicator for tooth maturity and age estimation in children aged 3-8 years.

CLINICAL RELEVANCE

Age assessment based on radiographs is considered as a reliable and efficient indicator for judging different types of malocclusion, making suitable orthodontic treatment plan, deciding the extraction time of retained deciduous teeth in clinic practice.

Comperative evaluation of Nolla, Willems and Cameriere methods for age estimation of Turkish children in the Central Black Sea Region: A preliminary study

PURPOSE

Since dental age estimation methods' accuracy and reliability levels differ in each society, the method should be appropriate for societies. This study aims to evaluate the applicability of Nolla, Willems, and Cameriere methods to Turkish children in the Central Black Sea Region.

MATERIAL AND METHOD

This study was conducted based on the panoramic radiographs of 400 children between the ages of 6-14 years admitted to Tokat Gaziosmanpaşa University Faculty of Dentistry, Department of Pediatric Dentistry for examination between 2016 and 2020. Nolla, Willems, and Cameriere methods estimated dental age on the selected panoramic radiographs. While 14 teeth in the left mandible and maxilla were evaluated for Nolla method, seven teeth in the left mandible were evaluated for Willems and Cameriere methods. Data were analyzed using IBM SPSS V23. The Pearson correlation coefficient was used to analyze the relationship between the chronological age (CA) and dental age (DA), and the paired sample t-test was used to analyze the difference.

RESULTS

A statistically significant difference was found between CA-Nolla dental age (p = 0.002), CA-Willems dental age (p < 0.001), and CA-Cameriere dental age (p = 0.033) in boys. The mean differences between dental age and chronological age in boys were -0.24 years in the Nolla method, +0.49 years in Willems method, and -0.17 years in the Cameriere method. A statistically significant difference was found between CA-Nolla dental age (p = 0.001) and CA-Willems dental age (p < 0.001) in girls. The mean differences between dental age and chronological age in girls were -0.27 years in the Nolla method, +0.76 years in the Willems method, and -0.1 years in the Cameriere method.

CONCLUSION

In this study method providing closest estimation for chronological age among children aged 6-14.99 that were examined in Central Black Sea Region, was the Cameriere method in both girls (79.9%) and boys (80.6%), followed by Nolla method and Willems method, respectively.

Age estimation in humans through the analysis of aspartic acid racemization from teeth: A scoping review of methods, outcomes, and open research questions

Teeth are considered the most resistant structures in the human body. In forensic odontology, teeth are useful for human identification, especially when dental age estimation is necessary. Despite numerous studies, there is no consensus regarding the best methods for dental age estimation. The analysis of aspartic acid racemization, however, has shown promising results. This scoping review aimed to present a descriptive synthesis of the current literature regarding dental age estimation through aspartic acid racemization. Four electronic databases were screened: PubMed, Scielo, Web of Science, and Scopus. Cross-sectional studies published before April 2021 were selected. From 206 articles found, 26 met the eligibility criteria. Several experimental protocols and laboratory settings were detected, but the different protocols did not seem to significantly reduce error rates in dental age estimation. The analysis of aspartic acid racemization in human dental tissues produced accurate and potentially reliable results for age estimation. Aspartic acid racemization stands out especially in the adulthood - age category in which other methods struggle to deliver proper performances. Studies with larger samples, independent testing, and standardized laboratory procedures are necessary. Equator-like reporting guidelines are encouraged to enable future systematic reviews and meta-analyses.

Dental age estimation of Tibetan children and adolescents: Comparison of Demirjian, Willems methods and a newly modified Demirjian method

Tibetan ethnic group is one of the oldest ethnic groups in China and South Asia. This study set out to analyze the dental development and validate Demirjian method and Willems method in estimating dental age of Tibetan children and adolescents, and to modify Demirjian method based on Tibetan population to provide ethnic-specific reference data and a more reliable method for forensic age assessment in Tibetan ethnic group. In this study, 1951 samples aged between 4 and 15 years were retrospectively collected and analyzed. Multiple linear regression was used to establish relationship between chronological age (CA) and developmental stages of left mandibular permanent teeth. The accuracy of the modified method was tested and compared with that of Demirjian and Willems method. Results showed that dental maturity score (DMS) was significantly greater in girls than in boys in all age groups except for the 4-year age group (p < 0.05). Mean absolute error (MAE) was 0.96 years for both boys and girls by Demirjian method, and 1.06 and 1.16 years for boys and girls respectively by Willems method. Adjusted scores table was established and tested. The age of boys was overestimated by 0.13 years and the age of girls was underestimated by 0.06 years by the adjusted scores table. MAE was lower than that of the other two methods. In conclusion, Demirjian method and Willems method was not sufficiently accurate in estimating dental age of Tibetan population. The modified method was more suitable for dental age estimation of Tibetan population than Demirjian and Willems method.

Analysis of interrater reliability in age assessment of minors: how does expertise influence the evaluation?

Nowadays, the clinical forensic medical management of migration flows comprises the age assessment of unaccompanied minors. The process of age estimation is a fundamental pillar for legally ensuring the minors' rights and their protection needs. The procedure is complex and involves different phases and actors, from medical doctors to law enforcement officers. The present study aimed to investigate the performance of Greulich and Pyle, Demirjian, and Mincer methods when performed by raters both trained and without training. Also, the interrater reliability within groups of raters from different areas of expertise was evaluated. A total of 36 participants were enrolled for this study, divided in two groups according to their level of experience with age estimation methods. Each rater was asked to allocate stages and standards for age assessment, evaluating ten orthopantomograms and ten hand-wrist roentgenograms. The interrater reliability expressed through the Fleiss Kappa coefficient and the agreement with the reference standard were calculated. The results showed that none of the categories analyzed could reach a good interrater reliability (ĸ > 0.8) for both methods. The study results highlighted variation and disagreement in the interpretation of the sample among raters and in the subsequent stages and standards allocation. In conclusion, the results of this study highlight that expertise does influence the reliability of the most utilized methods of age estimation of living individuals and stress the importance of proper training and practice, which could greatly increase the accuracy of age assessments.

Differences in third molar development and angulation in class II subdivision malocclusions

PURPOSE

To assess and compare the developmental stages and angulations of third molars between the class II and class I sides in class II subdivision malocclusions.

METHODS

This retrospective study was performed using panoramic x‑rays of 38 individuals (mean age: 15.5 years; 24 females, 14 males) with class II subdivision malocclusions, which were further divided into type 1 and 2 subgroups according to midline deviation, and a control group of 42 individuals (mean age: 17.0 years; 30 females, 12 males) with normal occlusion. Third molars were categorized using the developmental stages defined by the Demirjian method. Angles between the third molars and horizontal reference lines and also to the second molars were measured.

RESULTS

No difference was found in developmental stages or angulations between the left and right third molars in the control group. In the class II subdivision malocclusion cases, no difference in third molar developmental stages was observed, but the angle between the long axes of the mandibular third and second molars was significantly greater on the class II side. In the type 2 subgroup, developmental stage of the maxillary third molar was more advanced on the class II side. In both subgroups, the angles of the maxillary third molars' long axis to the interorbital plane differed significantly between the two sides.

CONCLUSION

Class II subdivision malocclusion may cause differences in third molar development and angulations between the two sides. Orthodontic treatment should be planned considering the third molars in this malocclusion.

Assessment of dental age estimation methods applied to Brazilian children: a systematic review and meta-analysis

OBJECTIVES

To review the scientific literature of studies on dental age estimation methods applied to Brazilian children.

METHODS

A systematic literature review was designed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered in PROSPERO (CRD42020136170). Six scientific databases were used as primary search sources (PubMed, Scopus, LILACS, SciELO, Embase and Web of Science) and two databases (Open Grey and Open Thesis) were searched to partially select the "grey literature." Only cross-sectional studies were included. The risk of bias was assessed by means of Joanna Briggs Institute Critical Appraisal Tools for Systematic Reviews. The standardized mean difference (SMD) between the estimated dental and chronological ages was meta-analysed via random effects model.

RESULTS

The search resulted in 2,527 studies, from which 13 met the eligibility criteria. Out of the eligible studies, 76.92% had low risk of bias and high methodological quality. Ten studies provided proper information to be included in the meta-analysis.The methods and their SMD between estimated and chronological ages were: Willems'=0.05, Lilequist and Lundberg's = -0.11, Nolla's = 0.22, Mornstad's = 0.27, Cameriere's = -0.31, Demirjian's = 0.74 and Haavikko's = -0.87.

CONCLUSION

Although originally trained in populations worldwide, most of the international methods for radiographical dental age estimation had optimal performance in Brazilian children.

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.

Dental age estimation: Demirjian's versus the other methods in different populations. A literature review

Age estimation is an important issue in forensic anthropology and odontology, since it is applied to both the living and the dead. Studies have shown that assessing tooth development using radiological methods is a reliable way to estimate age, especially in children. Demirjian's method is the most widely used estimation method for dental age evaluation. Over the years, many methods have been developed in order to asses which one predicts more accurately the age. In the literature, many populations were examined with these different methods and discordant results are described. This review aims to evaluate the studies in which Demirjian's method was compared with Willems', Cameriere's, Nolla's, Smith's, Haavikko's and Chaillet's methods in order to estimate the most accurate dental age estimation method in different populations. Using the methodology described in the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement, the authors conducted a review of existing literature using three databases: PubMed, Google Scholar and Google Scopus.

Above or below 14 years? An orthopantomographic study based on chronological course of eruption of mandibular premolars and second molars in a sample of south Indian children

In the context of dental age assessment, two significant factors can be studied; tooth mineralisation and tooth emergence. Little is known about the role of a second molar eruption in forensic age estimation. This paper aims to contribute to forensic age estimation using an age threshold of 14 years, studying the eruption stages of permanent mandibular premolars and second molars. Totally 640 orthopantomograms (OPGs) of south Indian children, aged between 10 and 18 years, were evaluated using Olze et al. staging of tooth eruption stages (A-D). Spearman's rho correlation showed a strong, positive, and statistically significant correlation between the chronological age and the eruption stages of both sexes' teeth. Accuracy, sensitivity, specificity, likelihood ratios, and post-test probability values were calculated for all tested teeth. The best performance to discriminate individuals above or below 14 years showed stage D in second molars. The sensitivity varied between 89% and 94% and specificity between 75% and 84%, respectively. Receiver operating characteristic curve analysis revealed high diagnostic performance for stage D, with area under the ROC curve (AUC) values of 84% and 85% for tooth 37 and 85% and 83% for tooth 47 in males and females, respectively. In conclusion, it is possible to predict age over 14 years in south Indian children using tooth emergence stages from OPGs with a relatively high interobserver agreement and good diagnostic accuracy. However, there are some limitations and, therefore, must be used in conjunction with other methods.

Accuracy assessment of dental age estimation with the Willems, Demirjian and Nolla methods in Spanish children: Comparative cross-sectional study

Background

The objective of this study was to evaluate and compare the validity and accuracy of the Willems, Demirjian and Nolla methods in predicting chronological age in a Spanish ethnicity population.

Methods

A sample of 604 orthopantomographs of Spanish children aged 4 to 13 years was evaluated by two independent evaluators. Descriptive statistics were applied to calculate the chronological age and dental age, presenting the mean and standard deviation. The difference between dental age and chronological age was calculated for each method. A positive result indicated an overestimation and a negative figure indicated an underestimation. The Wilcoxon test for paired data and Spearman’s correlation coefficient were applied by age groups and sex to compare the chronological age and dental age of each method (that of Willems, Demirjian and Nolla). Statistical tests were performed at a 95% confidence level.

Results

The interexaminer agreement was 0.98 (p = 0.00), and the intraexaminer agreement was 0.99 (p = 0.00). The Willems method significantly overestimated the age of boys (0.35 years (0.93)) and girls (0.17 years (0.88)). The Demirjian method significantly overestimated the age of boys (0.68 years (0.95)) and girls (0.73 years (0.94)). The Nolla method significantly underestimated age in boys (0.44 years (0.93)) and girls (0.82 years (0.98)).

Conclusions

In the Spanish population, the use of the Demirjian method for legal and medical purposes is frequent. This study reveals that the Willems method is more appropriate due to its greater precision in estimating dental age.

Comparison of actual porcine tooth crown development stages and computer image analysis

Tooth developmental stage evaluation is important in dental and chronological age estimation, and it is important for accurate diagnoses and appropriate treatment in dental practice. It is routinely assessed by clinical observations and radiographic techniques. This study aimed at ascertaining tooth developmental stage judgments made by examiners and Mimics software according to the Nolla method with radiographs. Meanwhile, the true tooth developmental stages would be explored with histological analysis. Twenty freshly slaughtered porcine heads were collected and hemisected, and both the left and right mandibular samples were numbered. The developmental stages of the second and third permanent molars (M2 and M3) were evaluated by examiners and Mimics software analysis. The ratio of the radiopaque calcified area to the dental follicle (RCA/DF) at different stages was calculated. Both non-decalcified and decalcified samples were processed for histologic observation. The results showed significant differences between RCA/DF ratios from different developmental stages. There was a high positive correlation between the examiners' evaluation results and Mimics analysis results. Radiograph judgments and histology observation results were consistent from Stages 2-6. However, radiograph images of Stage 1 samples showed only crypts present, while under a surgical operating microscope, a bell-shaped tooth germ was observed. This was also confirmed by normal and hard tissue histology. In conclusion, radiograph judgments made by either examiners or Mimics software were both reliable. Mimics analysis can be a useful tool in evaluating tooth developmental stages. However, judgments need to be made cautiously in early developmental stages.

Dental age assessment by tooth emergence counts its chronological age predictive value in normal occlusion Bogotanians (mestizos)

Objective: (1) To test Hägg-Taranger's method of dental age assessment (DAA) in Bogotanian children comparing findings by sex with Swedishes' standards and (2) to investigate its chronological age predictive value for identification purposes.Material and methods: Dental age was assessed in 5-14-year-old Bogotanians, 2075 girls and 2032 boys and compared with the method's standards. For statistical analysis, matched-pair signed-rank tests were used, and a regression model was used for investigating value as chronological age predictor from dental age.Results: No significant difference was found between means of dental ages of Bogotanians and Swedishes, except for the lower central incisors' and second molars' emergences. Differences by sex between dental age means were seen at all stages especially, in mixed dentition (p<.01), being Bogotanian girls earlier maturers than boys. The established regression model as chronological age predictor, was tested by the coefficient of determination, which was found r²=0.979 for girls, and 0.957 for boys.Conclusions: Sexual dimorphism in dental age suggests Hägg-Taranger's method for identification by sex at mixed dentition. Additionally, high coefficients of determination show its reliability as chronological age predictor for ages from 5 to 12 years in girls, and to 13 years in boys.