Estimating a person’s age is one of the most important aspects of human identification (Ubelaker and Khosrowshahi 2019). Dental age estimation significantly narrows the search possibilities of the suspected victim into the estimated ages and gender (Krishan et al. 2015). This study took place in Surabaya, East Java, Indonesia. We evaluated the applicability of the Willems method for Indonesian children, which are classified as the Mongoloid race, whereas the population of the established method was Caucasian.
In the scope of dental age estimation, the previous study by Olze et al. had reviewed various methods of dental development staging and found that the Demirjian method can define the chronological age accurately (Olze et al. 2005). In spite of that statement, another study suggested that the modification of the Demirjian method proposed by Willems showed higher accuracy in estimating age and has been tested in various populations (Willems et al. 2001, 2012; Grover et al. 2012; Ambarkova et al. 2014; Ye et al. 2014). The Willems method was considered to be applied in the Indonesian children population because of its accuracy, and there was no established dental age estimation method for Indonesian children.
The previous study in Malay children (Mongoloid race) found that the Willems method showed overestimation in age groups of 5 and 15 years, and underestimation in age groups of 10 years in both sexes, without a significant statistical difference (Ismail et al. 2018). Unlike the results of the previous study in Malay children, there was an underestimation of age observed in the present study, both boys and girls. Further statistical analysis suggested that there was no significant difference between CA and EDA in the boys’ group. However, a significant difference was observed in the girls’ group.
The differences in dental maturation between boys and girls that might cause significant mean age difference are more visible in the girls’ group, whereas girls experience earlier growth spurt phase than boys. The growth spurt phase in girls occurs in early birth periods, 6 until 7 years, and 12 to 14 years old. Some literature has discussed that the mean difference of the onset of a pubertal growth spurt in boys and girls is about 2 years earlier for girls (Burstone 1963; de Souza Araujo et al. 2011). A study by Nola (1960) stated that there are remarkable differences in the distribution of tooth calcification and mineralization between sexes. In general, girls begin and end their dental development earlier than boys (Nolla 1960; Chertkow 1980).
A study by Willems in 2001 confirmed the substantial overestimation of the dental age in Belgian Caucasians using the original methods by Demirjian. It claimed that significant overestimation is due in theory to the different rates of dental development in different populations (Willems et al. 2001). Evaluation of dental development was considered as a reliable method for predicting age, as maturation events associated with tooth formation are less variable, and the mineralization of teeth is not affected by the external factors, such as crowding, retention, or early extraction of deciduous teeth (Chertkow and Fatti 1979; Maia et al. 2010; Latić-Dautović et al. 2017). As a developing country with a huge population, socioeconomic and nutritional status may affect the skeletal and dental growth of children in Indonesia (Cameriere et al. 2007).
Routine radiographs for dental treatment such as panoramic and periapical may be used as evidence in the forensic fields. Estimating the dental age in children can be done by defining the calcification and mineralization of teeth. Some combined methods, such as hand-wrist radiograph, might be necessary for further consideration and investigation of the dental age estimation.