Age estimation was used in forensic anthropology to help in the identification of individual remains and living person. However, the estimation methods tend to be unique and applicable only to a certain population. This paper analyzed age estimation using twelve regression models carried out on X-ray images of the left hand taken from an Asian data set for subjects under the age of 19. All the nineteen bones of the left hand were measured using free image software and the statistical analysis were performed using SPSS. There are two methods to determine age in this study which are single bone method and all bones method. For single bone method, S-curve regression model was found to have the highest R-square value using second metacarpal for males, and third proximal phalanx for females. For age estimation using single bone, fifth metacarpal from males and fifth proximal phalanx from females can be used due to the lowest mean square error (MSE) value. To conclude, multiple linear regressions is the best techniques for age estimation in cases where all bones are available, but if not, S-curve regression can be used using single bone method.
In the context of dental age assessment, two significant factors can be studied; tooth mineralisation and tooth emergence. Little is known about the role of a second molar eruption in forensic age estimation. This paper aims to contribute to forensic age estimation using an age threshold of 14 years, studying the eruption stages of permanent mandibular premolars and second molars. Totally 640 orthopantomograms (OPGs) of south Indian children, aged between 10 and 18 years, were evaluated using Olze et al. staging of tooth eruption stages (A-D). Spearman's rho correlation showed a strong, positive, and statistically significant correlation between the chronological age and the eruption stages of both sexes' teeth. Accuracy, sensitivity, specificity, likelihood ratios, and post-test probability values were calculated for all tested teeth. The best performance to discriminate individuals above or below 14 years showed stage D in second molars. The sensitivity varied between 89% and 94% and specificity between 75% and 84%, respectively. Receiver operating characteristic curve analysis revealed high diagnostic performance for stage D, with area under the ROC curve (AUC) values of 84% and 85% for tooth 37 and 85% and 83% for tooth 47 in males and females, respectively. In conclusion, it is possible to predict age over 14 years in south Indian children using tooth emergence stages from OPGs with a relatively high interobserver agreement and good diagnostic accuracy. However, there are some limitations and, therefore, must be used in conjunction with other methods.
The study aimed to develop a novel and reliable age estimation method using three-dimensional surface area analyses of maxillary canine apices among Malaysian children using CBCT data. A validated regression equation for age estimation was derived and correlation between chronological age and the surface areas of the developing maxillary canine's apices were investigated. Variations based on ethnicities, gender and status of root development were also investigated in terms of fit to the age estimation model. CBCT images of the patients ranging in age from 7 to 14 years were included in the study. Training sample of 191 intact permanent maxillary canines was selected from 191 CBCT images belonging to 100 Malays and 91 Chinese. Moreover, an independent validation sample of 96 permanent maxillary canines was selected from 96 CBCT images belonging to 48 Malays and 48 Chinese. Three-dimensional image modeling and surface area analyses of the developing canine's apices were performed using Mimics and 3-Matics software. A strong correlation (r = 0.978) was observed between chronological age and surface area of the developing maxillary canine's apices. 95.6% of the variation in age can be explained by surface area of canine's apices, gender and status of the root development (open/closed apices). However, ethnicity did not contributed to the fit of age estimation model. Female showed advanced development as compared to male. Mean absolute error values indicated that this newly developed 3D surface area analyses of canine apex can be used as a reliable method for age estimation among Malaysian children.