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Validity of the Demirjian and Fishman Methods for Predicting Chronological Age Amongst Yemeni Children
Maktoom A Alqadi1, Amal H Abuaffan1
1Department of Orthodontics, Paedodontics and Preventive Dentistry, Faculty of Dentistry, University of Khartoum, Khartoum, Sudan.
Objectives:
There has been an increasing need for reliable chronological age (CA) estimation in several aspects, including orthodontic treatment needs and legal, civil and forensic purposes. This study aimed to assess the validity of the Demirjian and Fishman methods in predicting the CA of Yemeni children.
Methods:
This descriptive cross-sectional study was conducted at seven schools in Sana'a, Yemen, between December 2016 and December 2017. One orthopantomograph and one left hand-wrist X-ray were obtained for each child to calculate the dental age (DA) and skeletal age (SA) which were correlated and compared with the CA.
Results:
A total of 358 Yemeni children aged 8-16 years were included in this study. The mean CA, DA and SA were 12.00 ± 2.25, 11.34 ± 2.42 and 12.39 ± 1.65 years, respectively. The Demirjian method significantly underestimated the CA by 0.58 ± 1.25 years in the total sample and 0.73 ± 1.30 and 0.40 ± 1.17 years in males and females, respectively (P <0.001). The Fishman method significantly underestimated the CA by 0.23 ± 1.19 and 0.44 ± 1.26 years in the total sample and in males, respectively (P ≤0.02). The Fishman method insignificantly underestimated the females CA by 0.02 ± 1.08 years (P = 0.898).
Conclusions:
Yemeni CA is highly correlated to DA and SA estimated by the Demirjian and Fishman methods, respectively. The Fishman method was more accurate amongst Yemeni females. Results showed that Yemeni children are delayed in dental development and skeletal maturity.
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