Abstract:

Objective The purpose of this study was to observe the morphological changes of toothmarks in pocket limbs and to explore the durative development of bitemarks. Methods Firstly a toothmark model was established by using a universal testing machine and a self- made incisor nod which was pressed particularly on pocket limbs. The changes of toothmarks were observed on alive and dead animals with time elapsing. The scopes of bruise and inden were analyzed by soft on digital photos. The depth data of inden were collected by three dimensional laser measurement. Results The changes in the alive group were faster than that in dead group. There was no obvious fadeaway of bruise during 24 h. The scopes of inden were decreased remarkably in 1 h, while the decrease slowed down in the following hours. Conclusion The changes of indent are fast in pocket limb. It implies that bitemark evidence should be collected as fast as possible in cases.

Key words: toothmark, forensic medicine, three- dimensional measurement