Abstract:
Introduction: Age estimation takes part in a variety of situations, such as growth observation, immigrant registration, legal penalty judgment and body identification. Chronological age usually corresponds with stages of skeletal and dental development. Age estimation by using hand and wrist radiography is the first method of choice for many cases because it is uncomplicated, inexpensive and non-invasive. However, the validity of the result is still questionable mainly because of the influence of ethnic differences. Objectives: The primary aim of this study was to evaluate the accuracy and reliability of the commonly used age estimation methods on Thai population. The secondary aims were to compare the results between different methods and to find any possible relationship on Thai population. Materials and methods: Hand and wrist radiographs from the Department of Radiology, Faculty of Dentistry, Chulalongkorn University were collected. The radiographs were taken between 2011 – 2016 and the patients must not have history of diseases that affect skeletal development. ‘Greulich and Pyle’, ‘Tanner and Whitehouse (TW3-RUS)’, and ‘Fishman’ method were applied for each radiograph. The results from each method and the chronological age were compared using Friedman’s rank test (p<0.05) followed by a Wilcoxon signed ranks test with Bonferroni correction. Results and Discussion: The estimated ages from the three methods were significantly different from the chronological age (p<0.002), except for ‘Tanner and Whitehouse’ in male which showed no significant difference. Overall, the results from each method tended to be overestimated although the tendency of underestimation was found particularly in younger groups. The presence of discordance supported the influence of ethnical factor and secular change on skeletal maturation rate. Conclusions: Tanner and Whitehouse TW3-RUS method was more accurate in predicting the age of contemporary Thais; however, a further adaptation of the method to reduce the discrepancies in late teenagers is recommended.