Dental Age Assessment in Children: A Comparison of Four Methods in a Recent French Population

The aim of this study was to analyze the accuracy and the reliability of four methods of dental age estimation (Demirjian, Willems I, Willems II, and Chaillet standards) in a French population. Orthopantomograms of 743 children aged between 4 and 15 years were used. The Demirjian standards gave a consistent overestimation of dental age compared with chronological age (+0.45 and +0.46 years for girls and boys, respectively). We found that three modified methods were more accurate for both sexes than Demirjian's method: the Willems I method appeared to be more suitable when the sex and ethnicity are both known (?0.09 and +0.14 years for girls and boys, respectively); the Willems II method was more accurate for children of unknown sex (mean difference = 0.00 years), and the Chaillet method was found to be more accurate than the Demirjian method, but less accurate than the Willems I method (?0.59 and ?0.18 years for girls and boys, respectively).     

中国北方未成年人群牙龄推断研究

目的 运用Cameriere法和Willems法推断中国北方5～14岁人群牙龄,并比较两种方法牙龄推断的准确性.方法 收集西安交通大学口腔医院年龄在5～14岁的中国北方未成年人群拍摄的全口曲面断层片2000例,其中男性1000例,女性1000例.分别采用Cameriere法和Willems法进行牙龄推断,利用SPSS ...     

Accuracy of age estimation of radiographic methods using developing teeth

Developing teeth are used to assess maturity and estimate age in a number of disciplines, however the accuracy of different methods has not been systematically investigated. The aim of this study was to determine the accuracy of several methods. Tooth formation was assessed from radiographs of healthy children attending a dental teaching hospital. The sample was 946 children (491 boys, 455 girls, aged 3-16.99 years) with similar number of children from Bangladeshi and British Caucasian ethnic origin. Panoramic radiographs were examined and seven mandibular teeth staged according to Demirjian's dental maturity scale [A. Demirjian, Dental development, CD-ROM, Silver Platter Education, University of Montreal, Montreal, 1993-1994; A. Demirjian, H. Goldstein, J.M. Tanner, A new system of dental age assessment, Hum. Biol. 45 (1973) 211-227; A. Demirjian, H. Goldstein, New systems for dental maturity based on seven and four teeth, Ann. Hum. Biol. 3 (1976) 411-421], Nolla [C.M. Nolla, The development of the permanent teeth, J. Dent. Child. 27 (1960) 254-266] and Haavikko [K. Haavikko, The formation and the alveolar and clinical eruption of the permanent teeth. An orthopantomographic study. Proc. Finn. Dent. Soc. 66 (1970) 103-170]. Dental age was calculated for each method, including an adaptation of Demirjian's method with updated scoring [G. Willems, A. Van Olmen, B. Spiessens, C. Carels, Dental age estimation in Belgian children: Demirjian's technique revisited, J. Forensic Sci. 46 (2001) 893-895]. The mean difference (+/-S.D. in years) between dental and real age was calculated for each method and in the case of Haavikko, each tooth type; and tested using t-test. Mean difference was also calculated for the age group 3-13.99 years for Haavikko (mean and individual teeth). Results show that the most accurate method was by Willems [G. Willems, A. Van Olmen, B. Spiessens, C. Carels, Dental age estimation in Belgian children: Demirjian's technique revisited, J. Forensic Sci. 46 (2001) 893-895] (boys -0.05+/-0.81, girls -0.20+/-0.89, both -0.12 y+/-0.85), Demirjian [A. Demirjian, Dental development, CD-ROM, Silver Platter Education, University of Montreal, Montreal, 1993-1994] overestimated age (boys 0.25+/-0.84, girls 0.23+/-0.84, both 0.24 y+/-0.86), while Nolla [C.M. Nolla, The development of the permanent teeth, J. Dent. Child. 27 (1960) 254-266] and Haavikko's [K. Haavikko, The formation and the alveolar and clinical eruption of the permanent teeth. An orthopantomographic study, Proc. Finn. Dent. Soc. 66 (1970) 103-170] methods under-estimated age (boys -0.87+/-0.87, girls -1.18+/-0.96, both -1.02 y+/-0.93; boys -0.56+/-0.91, girls -0.79+/-1.11, both -0.67 y+/-1.01, respectively). For individual teeth using Haavikko's method, first premolar and second molar were most accurate; and more accurate than the mean value of all developing teeth. The 95% confidence interval of the mean was least for mean of all developing teeth using Haavikko (age 3-13.99 years), followed by identical values for Demirjian and Willems (sexes combined).     

应用Demirjian法进行法医学年龄推断的评价

目的对应用Demirjian法进行法医学年龄推断的准确度及可靠性进行初步评价。方法应用Demirjian法测定828名上海地区青少年(男279名,女549名,11～19周岁)的牙龄,比较所测牙龄和实际年龄的差异。结果在11～14岁年龄段Demirjian法测定的牙龄比实际年龄高估,在15～16岁年龄段低估,在17岁及17岁以上年龄段具有局限性。结论Demirjian法可以用于测定上海地区11～16岁年龄段青少年的牙龄,使用时需进行适当的修正。     

Age estimation by measurements of developing teeth: accuracy of Cameriere's method on a Brazilian sample

Developing teeth are commonly the criteria used for age estimation in children and young adults. The method developed by Cameriere et al. (Int J Legal Med 2006;120:49-52) is based on measures of teeth with open apex, and application of a formula, to estimate chronological age of children. The present study evaluated a sample of panoramic radiographs from Brazilian children from 5 to 15 years of age, to evaluate the accuracy of the method proposed by Cameriere et al. The results has proven the system reliable for age estimation, with a median residual error of -0.014 years between chronological and estimated ages (p = 0.603). There was a slight tendency to overestimate the ages of 5-10 years and underestimate the ages of 11-15 years.     

Age estimation in children by measurement of open apices in tooth roots: Study of a Mexican sample

The aim of this cross-sectional study was to test the accuracy of Cameriere's European formula for age assessment in a large sample of Mexican children. The accuracy of dental age estimation was defined as how closely real age, measured as the difference between chronological age (CA) and dental age (DA), could be predicted. Digitalized orthopantomographs of 502 Mexican children (254 girls and 248 boys), aged between 5 and 15 years, were analyzed. The seven left permanent mandibular teeth were evaluated using Cameriere's method. Intra- and inter-observer variability for this technique was tested on a small random sample. Dental age was estimated for each individual and compared with known chronological age. Accuracy was measured as the difference between known chronological age and dental age and tested for significance with the mean prediction error (ME). The standard deviation and 95% confidence interval of the mean difference were also calculated. ME was 0.63 years for girls and 0.52 years for boys. ME was found to be slightly overestimated by 0.10 years for girls, but was correctly estimated for boys with an accuracy of 0.00. In conclusion, this method is very useful and may be recommended for practical application both in clinical dentistry and forensic procedures on the Mexican population.     

Age Estimation from the Teeth Using a Modified Demirjian System*

Abstract: The estimation of age at time of death is often an important step in the identification of human remains. The purpose of this study was to test the applicability of the Demirjian system on a sample of the Sydney child population and to develop and test age‐prediction models using a large sample of Sydney children (1624 girls, 1637 boys). The use of the Demirjian standards resulted in consistent overestimates of chronological age in children under the age of 14 by as much as a mean of 0.99 years. Of the alternative predictive models derived from the Sydney sample, those that provided the most accurate age estimates are applicable for the age ranges 2–14 years, with R‐square = 0.94 and a 95% confidence interval of ±1.8 years. The Sydney‐based standards provided significantly different and more accurate estimates of age for that sample when compared to the published standards of Demirjian.     

Validity of Demirjian and Willems methods for dental age estimation for Malaysian children aged 5–15 years old

BackgroundOne of the most commonly used method for dental age assessment is the method reported by Demirjian and coworkers in 1973. It was later modified by Willems and coworkers whereby they “performed a weighted ANOVA” in order to adapt the scoring system.AimTo evaluate the applicability of Demirjian and Willems methods for dental age estimation for Malaysian children and to correlate the accuracy of the findings with the chronology of tooth development of premolars and second molars.Materials and methodsA total of 991 dental panoramic radiographs of 5–15-year-old Malaysian children were included in the study. The mean Demirjian and Willems estimated ages were compared to the mean chronological age.ResultsThe mean chronological age of the sample was 10.1 ± 2.8 and 9.9 ± 3.0 years for males and females respectively. Using the Demirjian method, the mean estimated dental age was 10.8 ± 2.9 years for males and 10.5 ± 2.9 years for females. For Willems method, the mean estimated age was 10.3 ± 2.8 years males and 10.0 ± 3.0 years respectively.ConclusionsWillems method was more applicable for estimating dental age for Malaysian children. Overestimation in Demirjian method could be due to advanced development of second bicuspids and molars.     

Age Estimation in Indians Using Demirjian’s 8‐teeth Method

Abstract: Demirjian’s grading of tooth calcification is widely used to assess age of individuals with developing dentitions. However, its application on numerous populations has resulted in wide variations in age estimates and consequent suggestions for the method’s adaptation to the local sample. Conventionally, Demirjian’s method utilized seven mandibular teeth on the left side. A recent modification incorporated the third molar with a view to apply the method on a wider age‐group. Moreover, the revised method developed regression formulas for assessing age. This paper tested the 8‐teeth method using 547 Indians (348 females, 199 males) aged 7–25 years. Demirjian’s formulas resulted in inferior age prediction in Indians (9.2% misclassification at 99% confidence interval vs. 0% misclassification in the original study); therefore, India‐specific regression formulas were developed, which gave better age estimates (mean absolute error, MAE = 0.87 years) than the original formulas (MAE = 1.29 years). This suggests that Demirjian’s 8‐teeth method also needs adaptation prior to use in diverse populations.     

Permanent teeth development in a Spanish sample. Application to dental age estimation

The purpose of this study is to clarify the chronology of different stages of dental development, according to Demirjian, in a sample of Spanish children, which will enable us to build a database that will be used as a reference in regard to the dental development of individuals of our socio-geographic environment. In the same studied sample, a calculation of the dental age according to Demirjian was carried out. This study was conducted in a final sample consisting of 1010 orthopantograms, corresponding to Spanish children (485 boys and 525 girls) ages 2-16. Comparing the age of onset of the different stages among the children, evidence was found that girls had an earlier general development than boys. These differences were only statistically significant in teeth and concrete stages. The canine teeth revealed greater gender dimorphism, with significant differences in all stages compared with the upper canines. The method proposed by Demirjian for dental age calculation resulted in a significant overestimation of dental age in relation to the chronological age in boys (average of 0.87 years) and girls (average of 0.55 years). Data from this study may be used as reference for dental maturity, as well as a standard for estimating age in Spanish children.     

Approaches to chronological age assessment based on dental calcification

The aim of the present study was to find an accurate estimation of chronological age using a small number of selected teeth. For this purpose, the method devised by Nolla [C. Nolla, The development of the permanent teeth, J. Dent. Child. 27 (1960) 254-266.] was used: the development of each of the teeth was determined according to this method on 374 radiographs, 195 of boys (mean age 8.59) and 179 of girls (mean age 8.75). The 28 variables representing the calcification stages were analyzed using cluster analysis followed by multivariate analysis (multiple linear regression model). Patient age was considered to be a dependent variable. Our study showed that antimere teeth are the most homogeneous as regards stages of development. The prediction was more accurate for boys and girls below 10 years of age, using teeth 21, 43 and 46 from boys and teeth 21, 46 and 47 from girls. These teeth accounted for 80% total variance of chronological age for dental calcification. Standard error was +/-1.4 years for boys and +/-1.2 years for girls. When the age of the children remained completely unknown, the best estimates were provided by teeth 43, 47, 46 and 44 from boys and teeth 44, 47 and 43 from girls.     

Dental age assessment: the applicability of Demirjian method in eastern Turkish children

In the literature, little is known about the applicability of this method in Turkish children. The aim of this study was, therefore, to evaluate the reliability of Demirjian method of age estimation when used for eastern Turkish children. A retrospective study was performed on a sample of panoramic radiographs taken from 807 healthy eastern Turkish children. The stages of dental maturity of the mandibular left seven permanent teeth for each subject using the eight radiographic dental maturity stages demonstrated by Demirjian were evaluated. A paired t-test was used for statistical analysis. The mean difference between the chronological and dental ages ranged from 0.2 to 1.9 years in girls and from 0.4 to 1.3 years in boys. The differences between the chronological and dental ages were statistically significant in all age groups. The applicability of Demirjian method is not suitable for eastern Turkish population.     

Optimal Dental Age Estimation Practice in United Arab Emirates’ Children

The aim of the study was to detect whether the Willems model, developed on a Belgian reference sample, can be used for age estimations in United Arab Emirates (UAE) children. Furthermore, it was verified that if added third molars development information in children provided more accurate age predictions. On 1900 panoramic radiographs, the development of left mandibular permanent teeth (PT) and third molars (TM) was registered according the Demirjian and the Kohler technique, respectively. The PT data were used to verify the Willems model and to develop a UAE model and to verify it. Multiple regression models with PT, TM, and PT + TM scores as independent and age as dependent factor were developed. Comparing the verified Willems‐ and the UAE model revealed differences in mean error of ?0.01 year, mean absolute error of 0.01 year and root mean squared error of 0.90 year. Neglectable overall decrease in RMSE was detected combining PM and TM developmental information.     

Testing the Demirjian and the international Demirjian dental aging methods on a mixed ancestry urban American subadult sample from Detroit, MI

This paper tests the Demirjian and international Demirjian dental aging methods for forensic use when ancestry and ethnicity are unknown. A radiographic sample of 187 boys and girls was collected from the Department of Pediatric Dentistry at the University of Detroit Mercy and aged using both methods. The total sample and the sample by age categories (young, middle, and old) were analyzed using t-tests. The Demirjian method was found to better estimate age to a statistically significant degree for the total sample, as well as the middle and old age categories. The young category was aged better using the international Demirjian method. The results indicate that while the Demirjian method accurately estimates age, caution must be used with the method. Further research is needed to determine whether the international Demirjian method can be used for forensics in the U.S.     

Age estimation using carpals: study of a Slovenian sample to test Cameriere's method

Carpals are often used as age indicators. In a recent study, Cameriere et al. studied the use of the ratio between the total area of carpal bones and epiphyses of the ulna and radius (Bo) and carpals (Ca) as age indicators. The present study, of a sample of 158 Slovenian children and adolescents aged between 6 and 16 years, focused on analysing the best regression for age estimation. The regression model yielded the following equation: age=-3.411+0.942 g+20.927(Bo/Ca), and explained 91.6% of total variance (R(2)=0.916). The median of the absolute values of residuals (observed age minus predicted age) was 0.09 years, with a quartile deviation of 0.786 years, and a standard error of estimate of 0.658 years. Comparisons between the previous equation referring to Slovenian children and the equivalent linear equation proposed by Cameriere et al. did not reveal any significant differences between the intercepts and slopes of the two linear models. These results suggested a common regression model for both Italian and Slovenian samples. The common regression model, describing age as a linear function of gender and Bo/Ca ratio, yielded the following linear regression formula: age=-2.907+0.408 g+20.757(Bo/Ca). This model explained 86% of total variance (R(2)=0.86). The median of the absolute values of residuals (observed age minus predicted age) was 0.02 years, with a quartile deviation of 1.02 years and a standard error of estimate of 0.96 years.     

Accuracy of Three Age Estimation Methods in Children by Measurements of Developing Teeth and Carpals and Epiphyses of the Ulna and Radius

Abstract: The aim of this study was to compare the accuracy of three methods for age estimation in children: the measurements of open apices in tooth roots (T), the ratio between the total area of carpal bones and epiphyses of the ulna and radius (HW), and the combined method (THW). The sample consisted of 288 Caucasian Italian children (152 boys and 136 girls) aged between 5 and 15 years. Accuracy was determined as the difference between estimated age and chronological age, and accuracy was assessed by analyzing individuals’ orthopantomograms and hand‐wrist radiographs. Accuracies were 0.41 years for girls and 0.54 years for boys with the THW method; for the HW method, 1.00 years for girls and 0.92 years for boys; and for the T method, 0.62 years for girls and 0.71 years for boys. THW is the most accurate technique for age estimation in these children.     

The accuracy of three methods of age estimation using radiographic measurements of developing teeth

The accuracy of age estimation using three quantitative methods of developing permanent teeth was investigated. These were M?rnstad et al. [Scand. J. Dent. Res. 102 (1994) 137], Liversidge and Molleson [J. For. Sci. 44 (1999) 917] and Carels et al. [J. Biol. Bucc. 19 (1991) 297]. The sample consisted of 145 white Caucasian children (75 girls, 70 boys) aged between 8 and 13 years. Tooth length and apex width of mandibular canine, premolars and first and second molars were measured from orthopantomographs using a digitiser. These data were substituted into equations from the three methods and estimated age was calculated and compared to chronological age. Age was under-estimated in boys and girls using all the three methods; the mean difference between chronological and estimated ages for method I was -0.83 (standard deviation +/-0.96) years for boys and -0.67 (+/-0.76) years for girls; method II -0.79 (+/-0.93) and -0.63 (+/-0.92); method III -1.03 (+/-1.48) and -1.35 (+/-1.11) for boys and girls, respectively. Further analysis of age cohorts, found the most accurate method to be method I for the age group 8.00-8.99 years where age could be predicted to 0.14+/-0.44 years (boys) and 0.10+/-0.32 years (girls). Accuracy was greater for younger children compared to older children and this decreased with age.     

Third Molar Development: Evaluation of Nine Tooth Development Registration Techniques for Age Estimations

Multiple third molar development registration techniques exist. Therefore the aim of this study was to detect which third molar development registration technique was most promising to use as a tool for subadult age estimation. On a collection of 1199 panoramic radiographs the development of all present third molars was registered following nine different registration techniques [Gleiser, Hunt (GH); Haavikko (HV); Demirjian (DM); Raungpaka (RA); Gustafson, Koch (GK); Harris, Nortje (HN); Kullman (KU); Moorrees (MO); Cameriere (CA)]. Regression models with age as response and the third molar registration as predictor were developed for each registration technique separately. The MO technique disclosed highest R² (F 51%, M 45%) and lowest root mean squared error (F 3.42 years; M 3.67 years) values, but differences with other techniques were small in magnitude. The amount of stages utilized in the explored staging techniques slightly influenced the age predictions.     

Estimating age in Maori, Pacific Island, and European children from New Zealand

The islands of New Zealand are populated by persons of European, Maori, and Pacific Island extraction. The purpose of this research is to quantify the levels of dental maturation of each of these three populations, in order to obtain data that will be useful in forensic identification and age estimation. The sample consisted of 1383 orthopantomographs (660 males, 723 females) of 477 Maori, 762 European, and 144 Pacific Island children between the ages of 3 and 14 years. Each radiograph was digitized and the stages of mineralization of the seven left mandibular permanent teeth were assessed using the eight stages described by Demirjian. Values for 1, 3, 5, 50, 95, 97, and 99% confidence intervals are listed for each maturity score. Intra-observer reliability was evaluated using Bland-Altman's method on data from re-scoring one out of every 20 radiographs and standard dental maturation curves were constructed for the three populations by means of a quantile regression method. Despite the fact that quantile regression analysis showed that across the age group investigated there were differences between boys and girls, knowledge of the sex does not increase the accuracy of the age estimate, simply because the magnitude of the error of age estimation is greater than the difference between the sexes. Our analysis also shows that population divergence is most marked after the age of 9 years, with a peak difference seen at age 10.