- Email: [email protected]
The applicability of Willems' method for age estimation in southern Turkish children: A preliminary study
Journal of Forensic and Legal Medicine 38 (2016) 24e27
Contents lists available at ScienceDirect
Journal of Forensic and Legal Medicine j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / j fl m
Original Communication
The applicability of Willems' method for age estimation in southern Turkish children: A preliminary study € € zer c, Halenur Onat Altan a, Ahmet Altan b, *, Fundagül Bilgiç c, Ozlem Akıncı So _ Ibrahim Damlar c a b c
Department of Pediatric Dentistry, Faculty of Dentistry, Gaziosmanpasa University, Tokat, Turkey Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Gaziosmanpasa University, Tokat, Turkey Faculty of Dentistry, Mustafa Kemal University, Hatay, Turkey
a r t i c l e i n f o
a b s t r a c t
Article history: Received 5 September 2015 Received in revised form 13 November 2015 Accepted 16 November 2015 Available online 26 November 2015
The aims of the present study were to evaluate the applicability and accuracy of Willems' method for assessing southern Turkish children and to analyze the practicability of this method in different age groups for both genders. Panoramic radiographs of 756 children (378 females, 378 males) aged between 5 and 14.99 years were examined by one observer. This retrospective study involved a contemporary southern Turkish population. The chronological ages of the subjects were divided into 10 groups. These 10 groups consisted of children of the following ages 5 and 14.99. Relationships between continuous variables were examined using Pearson's correlation coefficient. The paired t-test was used to compare all data according to gender and age groups. A p-value of less than 0.05 was considered significant for all statistical data. According to the results, a very high correlation was found for both girls (r2 ¼ 0.946) and for boys (r2 ¼ 0.940). Dental age (DA) and chronological age (CA) were consistent for girls in the four age groups (5e5.99, 6e6.99, 12e12.99, and 14e14.99) and for boys in the three age groups (5e5.99,13e13.99, 14 e14.99). The maturity score of Willems' Belgian samples of the DA was applicable to seven groups of the southern Turkish children. The present study reports that Willems' method is more accurate for girls than for boys. © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Keywords: Age estimation Dental age Willems' method
1. Introduction In the legal process, determining age is important in terms of both penalties and the law. It is particularly critical to determine whether the respective person is over 7, 12, 15, and 18 years of age in Turkey.1,2 Knowing the person's age helps to determine his employment, school, and military recruitment status; whether he has penal and legal liability; and whether he is capable of understanding the legal meaning and consequences of the action he committed.2 If there is no accurate data for a person's age, then bones, height, and teeth can be used to determine their age.3 Dental age (DA)
* Corresponding author. Ali Sevki Erek Yerleskesi Tokat, Postal Code: 60150, Turkey. Tel.: þ90 5057013189; fax: þ90 3562124225. E-mail address: [email protected] (A. Altan).
assessment based on dental maturity, especially pediatric dentistry and orthodontics, is one of the most reliable indicators of chronological age (CA). It is the most widely used assessment in pediatric endocrinology and in forensic, legal, and clinical dentistry.4,5 There are various methods for establishing age based on dental tissues, including the following: morphological(dental attrition rate, tooth color changing), metrical(Carbon14 analysis, histological analysis), radiomorphological(Demirjian's methods), and radio€ rnstaad' methods).5,6 In terms of metrical(Cameriere's methods, Mo age estimation, teeth are divided into two main periods: primary teeth and permanent teeth.7,8 Reliability is higher in the examination of primary teeth (formation of mineralization, neonatal line, and micrometric measurements, etc.) and thus age can be determined with low error rates.7 During the childhood period, there is constant change in the jaw bone because of the loss of primary teeth and the eruption, mineralization, and formation of permanent teeth. During this period, age estimation is mostly done by
http://dx.doi.org/10.1016/j.jflm.2015.11.015 1752-928X/© 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
H. Onat Altan et al. / Journal of Forensic and Legal Medicine 38 (2016) 24e27
comparing the drawings and tables of dentition development with radiographs.9,10 Determining the age based on bone development is the most frequently used method.11 Dental tissues are less affected by endocrine disorders or by dietary differences compared to other tissues in the body.12,13 If one of the teeth is fully mineralized, its form is stable, and developmental and retroactive variations in this status relate to CA.3 Human growth is a complex process that is mainly genetically but also environmentally determined. The body growth due to the proliferation of tissues is regulated by several environmental factors. These factors can be affected adversely by increasing consumption of processed foods, additives, toxins and environmental pollution, insufficient sunlight exposure, and inactivity.12 Adversely affected body balance and chronic diseases (diabetes, thyroid disorders, and heart disorders) that delay dental growth have been observed among very young children. Methods involving teeth for age estimation among children were developed by Nolla in 1960,14 by Moorrees in 1963,15 by Haavikko in 1970,16 and by Demirjian in 1973.10 These methods are all based on morphological evaluation of dental growth. The most frequently used method to determine age according to dental growth is Demirjian's method.4,10 Dental growth in this method is described in eight stages from A to H and evaluations are made on the left lower jaw on seven molar teeth (except the wisdom teeth). A total score out of 100 for dental growth is determined by checking the respective values of the table at the growth stage of each tooth, and DA can be estimated based on the standards that have been created. As the estimations using Demirjian's method began to give over estimation results than just the CA, Willems et al. revised the method.17 Demirjian's method is based on dental maturity. However, in the studies carried out in Turkey, particularly in regions that have hot climates (Mediterranean region, Aegean region, and Middle Anatolia), Demirjian's method is valid but not fully compatible.2,18 There is a lack of contemporary DA estimation standards for the southern Turkish population. The aims of the present study were to evaluate the applicability and accuracy of Willem's method for assessing the ages of southern Turkish children and to analyze the practicability of this method in different age groups for both genders. 2. Material and methods In this study, 756 children were selected, including 378 males and 378 females. The panoramic radiographs were selected from child patients referred to the Faculty of Dentistry of Mustafa Kemal University in Hatay, Turkey. This retrospective study involved a contemporary Turkish population. The inclusion criteria were as follows: aged between 5 and 14.99 years old; the quality of the panoramic radiographs was good and clear; and the subjects are free of systemic disorders, experienced a normal eruption of teeth, and have no pathological structure related jaw bone. Participants were selected from among Turkish citizens born in Hatay, Turkey. The exclusion criteria were children with congenital anomalies; cases of serious illness and dental trauma; a history of previous orthodontic treatment; dental deformities; absent lower teeth (except for the third molar); any pathological condition related to alveolar jaw bone (odontoma, cysts); systemic diseases; and unclear radiographs. All radiographs were obtained using Planmeca Promax (Helsinki, Finland), performed at 66e70 kV, 11e14 mA, 6.2 s exposure time, pulse X-ray. The CA of each patient was calculated according to Willems' method score and converted into decimal ages. The date of birth of each child was not known to the researcher to avoid bias during the
25
analyses of the dental stages. Dental maturity of the entire sample was accessed according to Willems et al.'s scoring method.17 The chronological ages of the subjects were divided into the following 10 age groups: (1) 5e5.99 years, (2) 6e6.99 years, (3) 7e7.99 years, (4) 8e8.99 years, (5)9e9.99 years(6) 10e10.99 years, (6) 11e11.99 years, (7) 12e12.99 years, (8) 13e13.99 years, (9) 14e14.99 years. After calculation and calibration, all radiographs were assessed by the second author. The test of the practicability and reproducibility of the applied methods involved 70 radiographs (10% from each age category), which were selected and reassessed by the same author six months after the first assessment. Therefore, to evaluate intra-observer agreement, Cohen's Kappa test was applied. Ethics committee approval was not required for the present study. 2.1. Statistical analysis Statistical analysis was performed using Statistical Package for Social Sciences (SPSS) for Windows 21.0 software. Relationships between continuous variables were examined using Pearson's correlation coefficient. The paired t-test was used to compare all data according to gender and age groups. A p-value of less than 0.05 was considered significant for all statistical data. 3. Results The present study included 756 healthy southern Turkish children, including 378 females (50%) and 378 males (50%). Age and gender distributions in the present study population are shown in Table 1. According to the results, a very high correlation was determined for both females (r2 ¼ 0.946) and males (r2 ¼ 0.940). Dental age was overestimated by 0.34 when using Willems' method. The mean differences between the chronological and dental ages ranged from 0.29 to þ0.82 years for females and from 0.02 to þ0.90 years for males in Table 2. The figures written in bold font in Table 2 indicate p values larger than 0.05. The individuals in this age group have similar dental and chronological ages, where DA and CA were consistent for females in four age groups (5e5.99, 6e6.99, 12e12.99, and 14e14.99) and for males in three age groups (5e5.99,13e13.99 and 14e14.99). Dental and chronological ages were significantly different for males and females in other age groups. 4. Discussion The city of Hatay, where the present study was conducted, is one of the oldest settlements of Turkey and is on the Eastern Mediterranean region. The city has a typical Mediterranean climate, with a hot and dry summer season and a warm and rainy winter season.
Table 1 Distribution of age and gender in study population. Age (Years)
Female
Male
Total
5e5.99 6e6.99 7e7.99 8e8.99 9e9.99 10e10.99 11e11.99 12e12.99 13e13.99 14e14.99 Total
29 27 39 37 47 48 46 43 29 33 378
31 23 41 30 50 52 55 44 34 18 378
60 50 70 67 97 100 101 87 63 51 756
26
H. Onat Altan et al. / Journal of Forensic and Legal Medicine 38 (2016) 24e27
Table 2 Differences between chronological age and dental age determined by Williems' method. Age groups
5e5.99 6e6.99 7e7.99 8e8.99 9e9.99 10e10.99 11e11.99 12e12.99 13e13.99 14e14.99
Females
Males
n
DA-CA
S.D.
Min.
Max.
p
n
DA-CA
S.D.
Min.
Max.
p
29 27 39 37 47 48 46 43 29 33
0.06 0.01 0.41 0.20 0.29 0.43 0.53 0.30 0.82 0.15
0.49 0.47 0.82 0.55 0.72 0.95 0.69 1.25 1.27 1.34
0.85 1.12 1.34 1.34 1.28 1.32 0.64 2.29 1.01 1.93
0.85 0.87 2.78 1.16 1.67 2.88 3.54 4.49 3.49 2.49
0.503 0.881 0.003 0.029 0.008 0.003 0.000 0.120 0.002 0.520
31 23 41 30 50 52 55 44 34 18
0.12 0.61 0.90 0.51 0.57 0.45 0.53 0.31 0.02 0.06
0.40 0.13 0.65 0.10 0.93 0.91 0.96 1.00 0.85 1.30
0.59 0.87 0.79 1.08 0.58 1.52 2.38 2.40 1.65 2.10
0.95 1.96 3.03 1.60 2.95 2.78 2.10 2.34 1.34 2.06
0.087 0.000 0.000 0.000 0.000 0.001 0.000 0.040 0.849 0.832
Syria is to the east and south of the city, and Adana, Osmaniye, and Gaziantep are to the west and north of the Mediterranean. In addition, Hatay receives a significant amount of external migration from Syria due to that country's civil war and internal migration from the surrounding provinces. As a result of such migration patterns, the rate of doubtful deaths, cases where individuals' identities cannot be determined, and incidents where determining the age of dead babies is required have increased. For the reasons stated above, the applicability of Willems' method to determine age was evaluated in Hatay where the case of age determination is common. Willems et al.17 published their revised maturity scores almost 25 years after Demirjian et al.'s study.10 In this 25-year interval, dental maturation has changed rapidly due to refined food, immobility, and decreased exposure to sunlight. Therefore, Willems et al.'s maturity scores more accurately reflect the present time than Demirjian's method. According to previous research, once the age range of individuals in a working group grows, the accuracy of the results obtained from the methods used in that study decreases. For this reason, our study age range is limited from 5 to 14.99.6 In a retrospective study of a western Turkish population, Altunsoy et al.19 showed that the differences between CA and DA ranged from 0.10 to 0.76 years for males and from 0.28 to 0.87 years for females. Their study also shows that the applicability of Demirjian's method is not suitable for an eastern Turkish population. lu et al.20 reported an overestimation of the DA (0.52 for Kırzıog males, 0.75 for females, and 0.64 in total) by using Demirjian's method in a sample from southern Turkey. Similarly, Celik et al.2 reported an overestimation in a population of southern Turkish children (ages 4e15 years) of the mean differences between the chronological and dental ages, which ranged from 1.20 to 1.36 years for females and from 1.02 to 1.69 years for males. A common outcome of most of these studies was that Demirjian's method inaccurately calculated DA in Turkish populations, especially in regions with warm climates.18 In the present study, according to the Willems' method, the mean differences between the chronological and dental ages ranged from 0.29 to þ0.82 years for females and from 0.02 to þ0.90 years for males. Males were more advanced in DA compared to females. Of all of the groups, the largest discrepancy between dental and chronological ages was found in the female group aged 13e13.99 and in the male group aged 7e7.99. Comparison of mean CA and DA for the sample and different age groups in the present study showed greater accuracy for females than for males. In the study group, Willems' method provides advanced DA results of 0.45 for males and 0.26 for females compared to the CA. According to the results, the DA of females was found to be higher than the CA compared to that DA of males. Similar to previous studies, the obtained result indicates that dental maturation is
faster in females than it is in males. This outcome may be explained by the fact that the warm climate can affect maturation among females. We found an overestimation for most of the age groups, and we observed underestimation only in the 9e9.99 year-old age group of females and in the 13e13.99 year-old age group of males. The present study is the first to test the accuracy of Willems' method for age estimation for southern Turkish populations. Until now, only one study on Willems' DA estimation among children in Turkey has been conducted. In a recent study undertaken in Ankara, a region adjacent to Middle Anatolia, Akkaya et al.21 reported an overestimation of the DA by using Willems' method (0.07 for males and 0.15 for females), and they found that Willems' method was more accurate for DA estimation of Turkish children compared to Demirjian's method. Our findings are consistent with Akkaya et al.'s21 study. The minor differences in the findings can be explained by the difference in the sample size, the method of age calculation, the age groups, the age and sex distribution of the original study populations, and the statistical methodologies.21 The number of people working abroad is higher in Hatay than other cities, and this situation which affects when fathers are able to register their young children. The father must wait to have a day off to register, and once the father comes to register his child, he does not declare his child's actual age in order to avoid paying a fine for late registration.22 However, the fine has been removed by the Ministry of Interior General Directorate of Population and Citizenship Affairs Circular 2006/6 No. 19828 of May 05, 2006. Moreover, while the father represents the unity of the family in the previous Turkish Civil Code (TCC), custody of the child is given to both parents in the new TCC.1 Estimated age and CA do not coincide in the youngest age group for both boys and girls (5e5.99) in our study. We have considered that this conformity might be associated with the increase in accurate registration with the correct year of birth in accordance with the amended law. The 31st Article of Turkish Penal Code (TPC) Law No. 5237 of 2006 regards those who have not reached the age of 12 as “not having criminal responsibility”.1,23 The TPC accepts that children who committed a crime at the age of 13e14 years understand the meaning and consequence of the crime. Children who have reached the age of twelve but have not yet reached the age of fifteen on the offence date may not have criminal responsibility if they are not sane and cannot be held responsible for their actions.23 According to the obtained results, Willems' method can be used in age estimation for boys between the ages of 13e13.99 and 14e14.99 and for girls between the ages of 12 and 12.99. An acceptable range in forensic anthropology is defined as ±1,0 year, but an acceptable mean age difference is ±0,5 year in previous studies.24 This score (0.34) in our study was in the acceptable range. According to our study's findings, Willems' method should be used for age estimation of southern Turkish females between the ages of 5e5.99, 6e6.99, 12e12.99, and 14e14.99 and for males between the
H. Onat Altan et al. / Journal of Forensic and Legal Medicine 38 (2016) 24e27
ages of 5e5.999, 13e13.99, and 14e14.99. According to our research, it is observed that the degree of reliability of Willems' method decreased according to CA in girls and boys in the mixed dentition stage. 5. Conclusion This study is the first investigation of the applicability of Willems' method to a southern Turkish population. The maturity score of Willems' Belgian samples of the DA was applicable in seven groups of southern Turkish children. The present study reports that the Willems' method is more accurate for females than for males. We believe this preliminary study will contribute to future research studies. Conflict of interest none. Funding None declared. Ethical approval None declared. References _ ¸ V. Understanding juvenile penal justice in Turkey. The criminalisation of Youth 1. Irtis Juvenile Justice in Europe, Turkey and Canada. Brussels: VUB PRESS Brussels University Press; 2010. p. 231e63. 2. Celik S, Zeren C, Celikel A, Yengil E, Altan A. Applicability of the Demirjian method for dental assessment of southern Turkish children. J Forensic Leg Med 2014 Jul;25:1e5. 3. Martrille L, Ubelaker DH, Cattaneo C, Seguret F, Tremblay M, Baccino E. Comparison of four skeletal methods for the estimation of age at death on white and black adults. J Forensic Sci 2007 Mar;52(2):302e7. 4. Tunc ES, Koyuturk AE. Dental age assessment using Demirjian's method on northern Turkish children. Forensic Sci Int 2008 Feb 25;175(1):23e6. 5. Willems G. A review of the most commonly used dental age estimation techniques. J Forensic Odonto Stomatol 2001 Jun;19(1):9e17. 6. Kvaal SI, Kolltveit KM, Thomsen IO, Solheim T. Age estimation of adults from dental radiographs. Forensic Sci Int 1995;74(3):175e85.
27
7. Aka PS, Canturk N, Dagalp R, Yagan M. Age determination from central incisors of fetuses and infants. Forensic Sci Int 2009;184(1):15e20. 8. Lysell L, Magnusson B, Thilander B. Time and order of eruption of the primary teeth. Odontol Revy 1962;13(3):217e35. 9. Demirjian A, Buschang PH, Tanguay R, Patterson DK. Interrelationships among measures of somatic, skeletal, dental, and sexual maturity. Am J Orthod 1985 Nov;88(5):433e8. 10. Demirjian A, Goldstein H, Tanner J. A new system of dental age assessment. Hum Biol 1973:211e27. 11. Reppien K, Sejrsen B, Lynnerup N. Evaluation of post-mortem estimated dental age versus real age: a retrospective 21-year survey. Forensic Sci Int 2006 May 15;159(Suppl. 1):S84e8. 12. Cameriere R, Flores-Mir C, Mauricio F, Ferrante L. Effects of nutrition on timing of mineralization in teeth in a Peruvian sample by the Cameriere and Demirjian methods. Ann Hum Biol 2007 SepeOct;34(5):547e56. 13. Rai BAS. Tooth developments: an accuracy of age estimation of radiographic methods. World J Med Sci 2006;1(2):130e2. 14. Nolla CM. The development of permanent teeth. University of Michigan; 1952. 15. Moorrees CF, Fanning EA, Hunt EE. Formation and resorption of three deciduous teeth in children. Am J Phys Anthropol 1963;21(2):205e13. 16. Haavikko K. The formation and the alveolar and clinical eruption of the permanent teeth. An orthopantomographic study. Suom Hammaslaak Toim 1970;66(3):103. 17. Willems G, Van Olmen A, Spiessens B, Carels C. Dental age estimation in Belgian children: Demirjian's technique revisited. J Forensic Sci 2001 Jul;46(4): 893e5. 18. Cantekin K, Ercan Sekerci A, Peduk K, Delikan E, Ozakar Ilday N, Demirbuga S, et al. Dental age assessment for different climatic regions. Am J Forensic Med Pathol 2014 Sep;35(3):197e200. 19. Altunsoy M, Nur BG, Akkemik O, Ok E, Evcil MS. Applicability of the Demirjian method for dental age estimation in western Turkish children. Acta Odontol Scand 2015 Feb;73(2):121e5. 20. Kirzioglu Z, Ceyhan D. Accuracy of different dental age estimation methods on Turkish children. Forensic Sci Int 2012 Mar 10;216(1e3):61e7. 21. Akkaya N, Yilanci HO, Goksuluk D. Applicability of Demirjian's four methods and Willems method for age estimation in a sample of Turkish children. Leg Med (Tokyo) 2015 Sep;17(5):355e9. 22. Arslan M, Çekin N, Akçan R, Saylak E. Evaluation of age estimation cases prosecuted in high criminal and civil courts of Hatay in 2007. J Forensic Med 2008;22(2):8e13. 23. Gulsahi A, Tirali RE, Cehreli SB, De Luca S, Ferrante L, Cameriere R. The reliability of Cameriere's method in Turkish children: a preliminary report. Forensic Sci Int 2015 Apr;249(319):e1e5. 24. Chaillet N, Willems G, Demirjian A. Dental maturity in Belgian children using Demirjian's method and polynomial functions: new standard curves for forensic and clinical use. J Forensic Odonto Stomatol 2004 Dec;22(2): 18e27.
Contents lists available at ScienceDirect
Journal of Forensic and Legal Medicine j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / j fl m
Original Communication
The applicability of Willems' method for age estimation in southern Turkish children: A preliminary study € € zer c, Halenur Onat Altan a, Ahmet Altan b, *, Fundagül Bilgiç c, Ozlem Akıncı So _ Ibrahim Damlar c a b c
Department of Pediatric Dentistry, Faculty of Dentistry, Gaziosmanpasa University, Tokat, Turkey Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Gaziosmanpasa University, Tokat, Turkey Faculty of Dentistry, Mustafa Kemal University, Hatay, Turkey
a r t i c l e i n f o
a b s t r a c t
Article history: Received 5 September 2015 Received in revised form 13 November 2015 Accepted 16 November 2015 Available online 26 November 2015
The aims of the present study were to evaluate the applicability and accuracy of Willems' method for assessing southern Turkish children and to analyze the practicability of this method in different age groups for both genders. Panoramic radiographs of 756 children (378 females, 378 males) aged between 5 and 14.99 years were examined by one observer. This retrospective study involved a contemporary southern Turkish population. The chronological ages of the subjects were divided into 10 groups. These 10 groups consisted of children of the following ages 5 and 14.99. Relationships between continuous variables were examined using Pearson's correlation coefficient. The paired t-test was used to compare all data according to gender and age groups. A p-value of less than 0.05 was considered significant for all statistical data. According to the results, a very high correlation was found for both girls (r2 ¼ 0.946) and for boys (r2 ¼ 0.940). Dental age (DA) and chronological age (CA) were consistent for girls in the four age groups (5e5.99, 6e6.99, 12e12.99, and 14e14.99) and for boys in the three age groups (5e5.99,13e13.99, 14 e14.99). The maturity score of Willems' Belgian samples of the DA was applicable to seven groups of the southern Turkish children. The present study reports that Willems' method is more accurate for girls than for boys. © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Keywords: Age estimation Dental age Willems' method
1. Introduction In the legal process, determining age is important in terms of both penalties and the law. It is particularly critical to determine whether the respective person is over 7, 12, 15, and 18 years of age in Turkey.1,2 Knowing the person's age helps to determine his employment, school, and military recruitment status; whether he has penal and legal liability; and whether he is capable of understanding the legal meaning and consequences of the action he committed.2 If there is no accurate data for a person's age, then bones, height, and teeth can be used to determine their age.3 Dental age (DA)
* Corresponding author. Ali Sevki Erek Yerleskesi Tokat, Postal Code: 60150, Turkey. Tel.: þ90 5057013189; fax: þ90 3562124225. E-mail address: [email protected] (A. Altan).
assessment based on dental maturity, especially pediatric dentistry and orthodontics, is one of the most reliable indicators of chronological age (CA). It is the most widely used assessment in pediatric endocrinology and in forensic, legal, and clinical dentistry.4,5 There are various methods for establishing age based on dental tissues, including the following: morphological(dental attrition rate, tooth color changing), metrical(Carbon14 analysis, histological analysis), radiomorphological(Demirjian's methods), and radio€ rnstaad' methods).5,6 In terms of metrical(Cameriere's methods, Mo age estimation, teeth are divided into two main periods: primary teeth and permanent teeth.7,8 Reliability is higher in the examination of primary teeth (formation of mineralization, neonatal line, and micrometric measurements, etc.) and thus age can be determined with low error rates.7 During the childhood period, there is constant change in the jaw bone because of the loss of primary teeth and the eruption, mineralization, and formation of permanent teeth. During this period, age estimation is mostly done by
http://dx.doi.org/10.1016/j.jflm.2015.11.015 1752-928X/© 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
H. Onat Altan et al. / Journal of Forensic and Legal Medicine 38 (2016) 24e27
comparing the drawings and tables of dentition development with radiographs.9,10 Determining the age based on bone development is the most frequently used method.11 Dental tissues are less affected by endocrine disorders or by dietary differences compared to other tissues in the body.12,13 If one of the teeth is fully mineralized, its form is stable, and developmental and retroactive variations in this status relate to CA.3 Human growth is a complex process that is mainly genetically but also environmentally determined. The body growth due to the proliferation of tissues is regulated by several environmental factors. These factors can be affected adversely by increasing consumption of processed foods, additives, toxins and environmental pollution, insufficient sunlight exposure, and inactivity.12 Adversely affected body balance and chronic diseases (diabetes, thyroid disorders, and heart disorders) that delay dental growth have been observed among very young children. Methods involving teeth for age estimation among children were developed by Nolla in 1960,14 by Moorrees in 1963,15 by Haavikko in 1970,16 and by Demirjian in 1973.10 These methods are all based on morphological evaluation of dental growth. The most frequently used method to determine age according to dental growth is Demirjian's method.4,10 Dental growth in this method is described in eight stages from A to H and evaluations are made on the left lower jaw on seven molar teeth (except the wisdom teeth). A total score out of 100 for dental growth is determined by checking the respective values of the table at the growth stage of each tooth, and DA can be estimated based on the standards that have been created. As the estimations using Demirjian's method began to give over estimation results than just the CA, Willems et al. revised the method.17 Demirjian's method is based on dental maturity. However, in the studies carried out in Turkey, particularly in regions that have hot climates (Mediterranean region, Aegean region, and Middle Anatolia), Demirjian's method is valid but not fully compatible.2,18 There is a lack of contemporary DA estimation standards for the southern Turkish population. The aims of the present study were to evaluate the applicability and accuracy of Willem's method for assessing the ages of southern Turkish children and to analyze the practicability of this method in different age groups for both genders. 2. Material and methods In this study, 756 children were selected, including 378 males and 378 females. The panoramic radiographs were selected from child patients referred to the Faculty of Dentistry of Mustafa Kemal University in Hatay, Turkey. This retrospective study involved a contemporary Turkish population. The inclusion criteria were as follows: aged between 5 and 14.99 years old; the quality of the panoramic radiographs was good and clear; and the subjects are free of systemic disorders, experienced a normal eruption of teeth, and have no pathological structure related jaw bone. Participants were selected from among Turkish citizens born in Hatay, Turkey. The exclusion criteria were children with congenital anomalies; cases of serious illness and dental trauma; a history of previous orthodontic treatment; dental deformities; absent lower teeth (except for the third molar); any pathological condition related to alveolar jaw bone (odontoma, cysts); systemic diseases; and unclear radiographs. All radiographs were obtained using Planmeca Promax (Helsinki, Finland), performed at 66e70 kV, 11e14 mA, 6.2 s exposure time, pulse X-ray. The CA of each patient was calculated according to Willems' method score and converted into decimal ages. The date of birth of each child was not known to the researcher to avoid bias during the
25
analyses of the dental stages. Dental maturity of the entire sample was accessed according to Willems et al.'s scoring method.17 The chronological ages of the subjects were divided into the following 10 age groups: (1) 5e5.99 years, (2) 6e6.99 years, (3) 7e7.99 years, (4) 8e8.99 years, (5)9e9.99 years(6) 10e10.99 years, (6) 11e11.99 years, (7) 12e12.99 years, (8) 13e13.99 years, (9) 14e14.99 years. After calculation and calibration, all radiographs were assessed by the second author. The test of the practicability and reproducibility of the applied methods involved 70 radiographs (10% from each age category), which were selected and reassessed by the same author six months after the first assessment. Therefore, to evaluate intra-observer agreement, Cohen's Kappa test was applied. Ethics committee approval was not required for the present study. 2.1. Statistical analysis Statistical analysis was performed using Statistical Package for Social Sciences (SPSS) for Windows 21.0 software. Relationships between continuous variables were examined using Pearson's correlation coefficient. The paired t-test was used to compare all data according to gender and age groups. A p-value of less than 0.05 was considered significant for all statistical data. 3. Results The present study included 756 healthy southern Turkish children, including 378 females (50%) and 378 males (50%). Age and gender distributions in the present study population are shown in Table 1. According to the results, a very high correlation was determined for both females (r2 ¼ 0.946) and males (r2 ¼ 0.940). Dental age was overestimated by 0.34 when using Willems' method. The mean differences between the chronological and dental ages ranged from 0.29 to þ0.82 years for females and from 0.02 to þ0.90 years for males in Table 2. The figures written in bold font in Table 2 indicate p values larger than 0.05. The individuals in this age group have similar dental and chronological ages, where DA and CA were consistent for females in four age groups (5e5.99, 6e6.99, 12e12.99, and 14e14.99) and for males in three age groups (5e5.99,13e13.99 and 14e14.99). Dental and chronological ages were significantly different for males and females in other age groups. 4. Discussion The city of Hatay, where the present study was conducted, is one of the oldest settlements of Turkey and is on the Eastern Mediterranean region. The city has a typical Mediterranean climate, with a hot and dry summer season and a warm and rainy winter season.
Table 1 Distribution of age and gender in study population. Age (Years)
Female
Male
Total
5e5.99 6e6.99 7e7.99 8e8.99 9e9.99 10e10.99 11e11.99 12e12.99 13e13.99 14e14.99 Total
29 27 39 37 47 48 46 43 29 33 378
31 23 41 30 50 52 55 44 34 18 378
60 50 70 67 97 100 101 87 63 51 756
26
H. Onat Altan et al. / Journal of Forensic and Legal Medicine 38 (2016) 24e27
Table 2 Differences between chronological age and dental age determined by Williems' method. Age groups
5e5.99 6e6.99 7e7.99 8e8.99 9e9.99 10e10.99 11e11.99 12e12.99 13e13.99 14e14.99
Females
Males
n
DA-CA
S.D.
Min.
Max.
p
n
DA-CA
S.D.
Min.
Max.
p
29 27 39 37 47 48 46 43 29 33
0.06 0.01 0.41 0.20 0.29 0.43 0.53 0.30 0.82 0.15
0.49 0.47 0.82 0.55 0.72 0.95 0.69 1.25 1.27 1.34
0.85 1.12 1.34 1.34 1.28 1.32 0.64 2.29 1.01 1.93
0.85 0.87 2.78 1.16 1.67 2.88 3.54 4.49 3.49 2.49
0.503 0.881 0.003 0.029 0.008 0.003 0.000 0.120 0.002 0.520
31 23 41 30 50 52 55 44 34 18
0.12 0.61 0.90 0.51 0.57 0.45 0.53 0.31 0.02 0.06
0.40 0.13 0.65 0.10 0.93 0.91 0.96 1.00 0.85 1.30
0.59 0.87 0.79 1.08 0.58 1.52 2.38 2.40 1.65 2.10
0.95 1.96 3.03 1.60 2.95 2.78 2.10 2.34 1.34 2.06
0.087 0.000 0.000 0.000 0.000 0.001 0.000 0.040 0.849 0.832
Syria is to the east and south of the city, and Adana, Osmaniye, and Gaziantep are to the west and north of the Mediterranean. In addition, Hatay receives a significant amount of external migration from Syria due to that country's civil war and internal migration from the surrounding provinces. As a result of such migration patterns, the rate of doubtful deaths, cases where individuals' identities cannot be determined, and incidents where determining the age of dead babies is required have increased. For the reasons stated above, the applicability of Willems' method to determine age was evaluated in Hatay where the case of age determination is common. Willems et al.17 published their revised maturity scores almost 25 years after Demirjian et al.'s study.10 In this 25-year interval, dental maturation has changed rapidly due to refined food, immobility, and decreased exposure to sunlight. Therefore, Willems et al.'s maturity scores more accurately reflect the present time than Demirjian's method. According to previous research, once the age range of individuals in a working group grows, the accuracy of the results obtained from the methods used in that study decreases. For this reason, our study age range is limited from 5 to 14.99.6 In a retrospective study of a western Turkish population, Altunsoy et al.19 showed that the differences between CA and DA ranged from 0.10 to 0.76 years for males and from 0.28 to 0.87 years for females. Their study also shows that the applicability of Demirjian's method is not suitable for an eastern Turkish population. lu et al.20 reported an overestimation of the DA (0.52 for Kırzıog males, 0.75 for females, and 0.64 in total) by using Demirjian's method in a sample from southern Turkey. Similarly, Celik et al.2 reported an overestimation in a population of southern Turkish children (ages 4e15 years) of the mean differences between the chronological and dental ages, which ranged from 1.20 to 1.36 years for females and from 1.02 to 1.69 years for males. A common outcome of most of these studies was that Demirjian's method inaccurately calculated DA in Turkish populations, especially in regions with warm climates.18 In the present study, according to the Willems' method, the mean differences between the chronological and dental ages ranged from 0.29 to þ0.82 years for females and from 0.02 to þ0.90 years for males. Males were more advanced in DA compared to females. Of all of the groups, the largest discrepancy between dental and chronological ages was found in the female group aged 13e13.99 and in the male group aged 7e7.99. Comparison of mean CA and DA for the sample and different age groups in the present study showed greater accuracy for females than for males. In the study group, Willems' method provides advanced DA results of 0.45 for males and 0.26 for females compared to the CA. According to the results, the DA of females was found to be higher than the CA compared to that DA of males. Similar to previous studies, the obtained result indicates that dental maturation is
faster in females than it is in males. This outcome may be explained by the fact that the warm climate can affect maturation among females. We found an overestimation for most of the age groups, and we observed underestimation only in the 9e9.99 year-old age group of females and in the 13e13.99 year-old age group of males. The present study is the first to test the accuracy of Willems' method for age estimation for southern Turkish populations. Until now, only one study on Willems' DA estimation among children in Turkey has been conducted. In a recent study undertaken in Ankara, a region adjacent to Middle Anatolia, Akkaya et al.21 reported an overestimation of the DA by using Willems' method (0.07 for males and 0.15 for females), and they found that Willems' method was more accurate for DA estimation of Turkish children compared to Demirjian's method. Our findings are consistent with Akkaya et al.'s21 study. The minor differences in the findings can be explained by the difference in the sample size, the method of age calculation, the age groups, the age and sex distribution of the original study populations, and the statistical methodologies.21 The number of people working abroad is higher in Hatay than other cities, and this situation which affects when fathers are able to register their young children. The father must wait to have a day off to register, and once the father comes to register his child, he does not declare his child's actual age in order to avoid paying a fine for late registration.22 However, the fine has been removed by the Ministry of Interior General Directorate of Population and Citizenship Affairs Circular 2006/6 No. 19828 of May 05, 2006. Moreover, while the father represents the unity of the family in the previous Turkish Civil Code (TCC), custody of the child is given to both parents in the new TCC.1 Estimated age and CA do not coincide in the youngest age group for both boys and girls (5e5.99) in our study. We have considered that this conformity might be associated with the increase in accurate registration with the correct year of birth in accordance with the amended law. The 31st Article of Turkish Penal Code (TPC) Law No. 5237 of 2006 regards those who have not reached the age of 12 as “not having criminal responsibility”.1,23 The TPC accepts that children who committed a crime at the age of 13e14 years understand the meaning and consequence of the crime. Children who have reached the age of twelve but have not yet reached the age of fifteen on the offence date may not have criminal responsibility if they are not sane and cannot be held responsible for their actions.23 According to the obtained results, Willems' method can be used in age estimation for boys between the ages of 13e13.99 and 14e14.99 and for girls between the ages of 12 and 12.99. An acceptable range in forensic anthropology is defined as ±1,0 year, but an acceptable mean age difference is ±0,5 year in previous studies.24 This score (0.34) in our study was in the acceptable range. According to our study's findings, Willems' method should be used for age estimation of southern Turkish females between the ages of 5e5.99, 6e6.99, 12e12.99, and 14e14.99 and for males between the
H. Onat Altan et al. / Journal of Forensic and Legal Medicine 38 (2016) 24e27
ages of 5e5.999, 13e13.99, and 14e14.99. According to our research, it is observed that the degree of reliability of Willems' method decreased according to CA in girls and boys in the mixed dentition stage. 5. Conclusion This study is the first investigation of the applicability of Willems' method to a southern Turkish population. The maturity score of Willems' Belgian samples of the DA was applicable in seven groups of southern Turkish children. The present study reports that the Willems' method is more accurate for females than for males. We believe this preliminary study will contribute to future research studies. Conflict of interest none. Funding None declared. Ethical approval None declared. References _ ¸ V. Understanding juvenile penal justice in Turkey. The criminalisation of Youth 1. Irtis Juvenile Justice in Europe, Turkey and Canada. Brussels: VUB PRESS Brussels University Press; 2010. p. 231e63. 2. Celik S, Zeren C, Celikel A, Yengil E, Altan A. Applicability of the Demirjian method for dental assessment of southern Turkish children. J Forensic Leg Med 2014 Jul;25:1e5. 3. Martrille L, Ubelaker DH, Cattaneo C, Seguret F, Tremblay M, Baccino E. Comparison of four skeletal methods for the estimation of age at death on white and black adults. J Forensic Sci 2007 Mar;52(2):302e7. 4. Tunc ES, Koyuturk AE. Dental age assessment using Demirjian's method on northern Turkish children. Forensic Sci Int 2008 Feb 25;175(1):23e6. 5. Willems G. A review of the most commonly used dental age estimation techniques. J Forensic Odonto Stomatol 2001 Jun;19(1):9e17. 6. Kvaal SI, Kolltveit KM, Thomsen IO, Solheim T. Age estimation of adults from dental radiographs. Forensic Sci Int 1995;74(3):175e85.
27
7. Aka PS, Canturk N, Dagalp R, Yagan M. Age determination from central incisors of fetuses and infants. Forensic Sci Int 2009;184(1):15e20. 8. Lysell L, Magnusson B, Thilander B. Time and order of eruption of the primary teeth. Odontol Revy 1962;13(3):217e35. 9. Demirjian A, Buschang PH, Tanguay R, Patterson DK. Interrelationships among measures of somatic, skeletal, dental, and sexual maturity. Am J Orthod 1985 Nov;88(5):433e8. 10. Demirjian A, Goldstein H, Tanner J. A new system of dental age assessment. Hum Biol 1973:211e27. 11. Reppien K, Sejrsen B, Lynnerup N. Evaluation of post-mortem estimated dental age versus real age: a retrospective 21-year survey. Forensic Sci Int 2006 May 15;159(Suppl. 1):S84e8. 12. Cameriere R, Flores-Mir C, Mauricio F, Ferrante L. Effects of nutrition on timing of mineralization in teeth in a Peruvian sample by the Cameriere and Demirjian methods. Ann Hum Biol 2007 SepeOct;34(5):547e56. 13. Rai BAS. Tooth developments: an accuracy of age estimation of radiographic methods. World J Med Sci 2006;1(2):130e2. 14. Nolla CM. The development of permanent teeth. University of Michigan; 1952. 15. Moorrees CF, Fanning EA, Hunt EE. Formation and resorption of three deciduous teeth in children. Am J Phys Anthropol 1963;21(2):205e13. 16. Haavikko K. The formation and the alveolar and clinical eruption of the permanent teeth. An orthopantomographic study. Suom Hammaslaak Toim 1970;66(3):103. 17. Willems G, Van Olmen A, Spiessens B, Carels C. Dental age estimation in Belgian children: Demirjian's technique revisited. J Forensic Sci 2001 Jul;46(4): 893e5. 18. Cantekin K, Ercan Sekerci A, Peduk K, Delikan E, Ozakar Ilday N, Demirbuga S, et al. Dental age assessment for different climatic regions. Am J Forensic Med Pathol 2014 Sep;35(3):197e200. 19. Altunsoy M, Nur BG, Akkemik O, Ok E, Evcil MS. Applicability of the Demirjian method for dental age estimation in western Turkish children. Acta Odontol Scand 2015 Feb;73(2):121e5. 20. Kirzioglu Z, Ceyhan D. Accuracy of different dental age estimation methods on Turkish children. Forensic Sci Int 2012 Mar 10;216(1e3):61e7. 21. Akkaya N, Yilanci HO, Goksuluk D. Applicability of Demirjian's four methods and Willems method for age estimation in a sample of Turkish children. Leg Med (Tokyo) 2015 Sep;17(5):355e9. 22. Arslan M, Çekin N, Akçan R, Saylak E. Evaluation of age estimation cases prosecuted in high criminal and civil courts of Hatay in 2007. J Forensic Med 2008;22(2):8e13. 23. Gulsahi A, Tirali RE, Cehreli SB, De Luca S, Ferrante L, Cameriere R. The reliability of Cameriere's method in Turkish children: a preliminary report. Forensic Sci Int 2015 Apr;249(319):e1e5. 24. Chaillet N, Willems G, Demirjian A. Dental maturity in Belgian children using Demirjian's method and polynomial functions: new standard curves for forensic and clinical use. J Forensic Odonto Stomatol 2004 Dec;22(2): 18e27.