Utilization of bone impedance for age estimation in postmortem cases

• The visual sagittal closure and its bone impedance was measured for age estimation.
• Bone impedance values increased with aging. But, it the decreased after the age of 64.5.
• In the visual analysis, the degree of closure varied greatly within age brackets.
• The bone impedance measuring technique may become a new method of age estimation.

In the field of Forensic Medicine the number of unidentified cadavers has increased due to natural disasters and international terrorism. The age estimation is very important for identification of the victims. The degree of sagittal closure is one of such age estimation methods. However it is not widely accepted as a reliable method for age estimation.In this study, we have examined whether measuring impedance value (z-values) of the sagittal suture of the skull is related to the age in men and women and discussed the possibility to use bone impedance for age estimation.Bone impedance values increased with aging and decreased after the age of 64.5.Then we compared age estimation through the conventional visual method and the proposed bone impedance measurement technique. It is suggested that the bone impedance measuring technique may be of value to forensic science as a method of age estimation.