Dental Age Estimation Using Percentile Curves and Regression Analysis Methods - A Test of Accuracy and Reliability

Abstract

Introduction: Age estimation using the developmental stages of tooth is considered the most reliable method for forensic investigations and for planning the age dependent treatment modalities in clinical applications. Aim: To evaluate the accuracy and reliability of percentile curves and regression analysis methods in dental age estimation of Indian population. Materials and Methods: The study includes orthopantomographs (OPGs) of 224 individuals (107 males and 117 females) belonging to the age group of 8-24 years. The study participants were divided into two groups as Group I (8 to 14 years) and Group II (15 to 24 years). The study groups were evaluated under two percentile curve methods (Demirjian's seven teeth method and Demirjian's eight teeth method) and two regression analysis methods (Indian specific models and South France models). The accuracy of each method was evaluated using Mean Errors (ME), Mean Absolute Errors (MAE) and Root Mean Square Error (RMSE), the reliability of each method was tested using the percentage of misclassifies (%M) under 99% of confidence intervals. Results: In Group I, for males South France regression models showed accurate (MAE=1.05) and reliable results (%M=0.15), for females Indian models showed accurate results (MAE=1.25) and South France models showed reliable results (%M=0.11). In Group II, for males (MAE=2.16; %M=0.67) and females (MAE=1.71; %M=0.58), Indian models showed accurate and reliable results. Conclusion: The regression analysis methods showed accurate and reliable results than the percentile curve methods in both the age groups.

Keywords

• developmental stages
• forensic odontology
• forensic sciences