137(S-06-5) Restoration of fossil crania using reference database

Correct assembly of fossil fragments into the original antemortem position is crucial for morphological analyses of fossil crania. Towards this, we have developed a computerized system to aid assembling isolated cranial fragments based on local shape information, i.e., surface smoothness of cranium. However, anatomically correct assembly of isolated cranial fragments based solely on local shape information may not necessarily yield satisfactory result. To realize globally consistent assembly of cranial fragments, exploitation of both local and global shape information seems necessary. Therefore, we started to assemble a cranial reference database to probabilistically represent global cranial morphology. Specifically, modern human crania were CT scanned to generate 3D cranial models and anatomical landmarks were digitized. We calculated shortest paths connecting pairs of the landmarks to represent surface morphology in-between the landmarks. Distributions of cranial morphology were described using geometrical and statistical methods. By exploiting both local shape information of individual fragments and global shape information of cranial shape complied in the database, we aim to realize anatomically consistent assembly of cranial fragments.