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This study aimed to examine the applicability of Willems' and Lee's methods in a Japanese population and to find the differences in teeth development between Japanese and Korean children by comparing the accuracy of their estimated age using the two methods. The developmental status of the lower left permanent teeth in 1,475 orthopantomograms of Japanese children were evaluated based on Demirjian's criteria, and the ages were estimated using Willems' and Lee's methods. The errors in estimated ages were calculated and compared with equivalent Korean population data. The accuracy of both methods for estimating the age of the Japanese population was similar to that in the Korean population except for that of Lee's method used in Japanese males. The results showed that there might be differences in teeth development between the Japanese and Korean boys. To increase the accuracy of the dental age estimation, the method that is derived from their own population data should be applied in forensic practice.

The present study of two case reports of the victims of the Great East Japan Earthquake demonstrates the effectiveness and limitations of using dental cone-beam computed tomography (CBCT) imaging of cremains as a means of identification. In case 1, identification was assisted by further expanding the age range of the cremains evaluated on macroscopy by obtaining CBCT images of the cremated maxilla. The findings of case 2 presented the possibility that the deceased and the candidate were the same person by superimposing the CBCT images of the cremated patella on the X-ray of the candidate. However, since cremated bones are deformed to varying degrees, it is clear that the images obtained before, rather than after, cremation are more effective in comparing post-mortem and ante-mortem images. Thus, it is necessary to collect extensive and diverse data on the deceased before cremation.

Age-related changes of protein carbonylation due to oxidative damage in human vitreous humors were analyzed. The vitreous samples were collected from 51 autopsied bodies (male: 27, 13-87 years-old, female: 24, 18-80 years-old) whose postmortem interval was less than 4 days. Total protein carbonyl content was assessed by colorimetry using 2,4-dinitrophenylhydrazine and particular carbonylated proteins were identified by immunostaining of vitreous proteins resolved by SDS-PAGE and MALDI-TOF MS with peptide mass fingerprinting. No significant correlation was found between total protein carbonyl content and biological age. However, two major proteins, albumin and transferrin, were found to be heavily carbonylated in the samples from individuals age 40 or over. Furthermore, an immunostained cluster of proteins at 50-60 kDa was discernible in the samples of aged individuals, and it was revealed to contain alpha enolase, pigment epithelial differentiating factor, type 2 keratin subunit protein, and S-arrestin. The results of this study suggest that some retinal proteins detected in the vitreous humor sample would be markers of age-related oxidative stress and biological age.