Although age estimation upon death is important in the identification of unknown cadavers for forensic scientists, to the best of our knowledge, no study has examined the utility of deep neural network (DNN) models for age estimation among cadavers. We performed a postmortem computed tomography (CT) examination of 1000 and 500 male and female cadavers, respectively. These CT slices were converted into 3-dimensional images, and only the thoracolumbar region was extracted. Eighty percent of them were categorized as training datasets and the others as test datasets for both sexes. We fine-tuned the ResNet152 models using the training datasets. We conducted 4-fold cross-validation, and the mean absolute error (MAE) of the test datasets was calculated using the ensemble learning of four ResNet152 models. Consequently, the MAE of the male and female models was 7.25 and 7.16, respectively. Our study shows that DNN models can be useful tools in the field of forensic medicine.

A studio arson attack in Japan caused 36 deaths. Dentists obtained dental findings from 33 unidentified bodies immediately after the attack and autopsy. The dental findings before autopsy were obtained on the day of the incident and the next day. Dental findings after autopsy were obtained at 1 week from the day after the incident. We examined issues associated with collecting these dental findings. Other findings recorded were CT images, autopsy findings, and various blood and pathological examinations. Among the 33 unidentified bodies, for 30 bodies, the number of teeth from which the dental findings were obtained was significantly higher after autopsy than before autopsy. The dental findings of the remaining three bodies were not obtained before or after the autopsy. Five percent of anterior teeth and 28.7% of molars had differing pre-autopsy and post-autopsy findings. This discrepancy can be attributed to various factors. One of the major influencing factors was the carbonization of the facial surface muscles and skin along with limited mouth opening due to thermocoagulation. For the scientific identification of an individual based on dental findings, it is mandatory to examine the teeth in all quadrants. The collection of dental findings solely from anterior teeth may not be adequate to establish identity. The present article describes the challenges faced by the dentists while identifying charred bodies in an arson attack.

(1) Background: While decreasing bone mineral density (BMD) with age in living people has been well documented, a correlation between age and bone mineral density in deceased people has only been reported in a few studies. A correlation between age and BMD in deceased people was investigated as an objective tool for age estimation of unidentified remains. (2) Methods: The Bone Area Ratio (BAR) was measured in 402 autopsy cases (143 females and 259 males over the age of 20). (3) Results: The correlation coefficient in the females was r = −0.5476, and the correlation coefficient in the males was r = −0.2166, indicating a stronger correlation in females than in males. A comparison of the BAR values in the deceased females for each age group with that in live females found no significant differences in the BAR values. BAR values in the deceased were similar to in live individuals, and this did not change with duration of the postmortem interval. (4) Conclusions: Measuring the BAR value based on bone mass using ultrasonic waves is rapid and easy, even for those lacking forensic training, and may be used to estimate the age of an individual and the likelihood of fracture due to trauma.

A woman in her seventies living alone was found dead on the floor of her living room. A blue-green swelling was found from her right cheek to her anterior neck and an autopsy was performed. The autopsy revealed subcutaneous abscesses from the right cheek to the anterior neck, posterior pharyngeal abscesses, mediastinal abscesses, pleuritis, and pericarditis. The cause of death was diagnosed as sepsis due to a retropharyngeal abscess caused by extensive severe periodontitis. The presence of a dentist at the autopsy allowed for a rapid diagnosis of periodontal disease, which was the cause of the posterior pharyngeal abscesses and septic shock. Therefore, the participation of a dentist in a forensic autopsy is important not only for personal identification but also for the rapid diagnosis of the cause of death.

Ketoacidosis is one of the common diseases that sometimes result in death. In forensic autopsy cases, the measuring of ketone bodies, especially β-hydroxybutyrate (BHB), is useful in diagnosing postmortem ketoacidosis as a cause of death. However, increased BHB values are not always indicative of ketoacidosis. Other causes of death, such as hypothermia, are known to increase BHB values. In addition, sometimes, we experience cases of increased BHB values that are unlikely to be associated with the pathophysiology or the cause of death resulting in an increase in BHB values. In this study, autopsies were performed to determine the relationship between blood BHB values and the postmortem interval (PMI). The patients were divided into four groups: PMI ≤ 24 h, PMI ≤ 48 h, PMI ≤ 72 h, and PMI > 72 h. The BHB values for each group were then compared. Based on the analysis, patients with a PMI ≤ 72 h and those with a PMI > 72 h had significantly higher BHB values than patients with a PMI ≤ 24 h. In conclusion, there remains a possibility that the BHB values increase after death. Forensic pathologists should consider PMI when diagnosing ketoacidosis as the cause of death.