Computerized restoration of nonhomogeneous deformation of a fossil cranium based on bilateral symmetry

Naomichi Ogihara, Masato Nakatsukasa, Yoshihiko Nakano, Hidemi Ishida

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

We developed a computerized method of correcting plastic deformation of a fossil skull, based on bilateral symmetry with respect to the midsagittal plane, and applied this method to reconstruction of a fossilized Proconsul heseloni cranium (KNM-RU-7290A). A three-dimensional (3D) model of the fossil was generated using consecutive cross-sectional images retrieved from computed tomography. 3D coordinates of anatomical landmarks that should be located on the midsagittal plane and pairs of landmarks that should be symmetrical with respect to this plane were acquired. These landmarks were then repositioned so that geometrical constraints were satisfied, while translated distances of landmarks were minimized. We adopted a thin-plate spline function to mathematically describe the 3D nonlinear volumetric transformation between acquired and repositioned landmarks. Using this function, the entire fossil shape was transformed, and the effect of reversing the deformation could be visualized. The results indicated that the proposed method was effective in eliminating nonhomogeneous deformation of the fossil skull. The antemortem appearance of the skull cannot be completely restored by this method alone, due to methodological limitations. However, the presented method has a role as an adjunct in complementing conventional restoration techniques on account of its objective nature.

Original languageEnglish
Pages (from-to)1-9
Number of pages9
JournalAmerican Journal of Physical Anthropology
Volume130
Issue number1
DOIs
Publication statusPublished - 2006 May
Externally publishedYes

Fingerprint

Skull
restoration
fossils
skull
methodology
Plastics
computed tomography
reconstruction
Tomography

Keywords

  • Computed tomography
  • Proconsul
  • Surface model
  • Thin-plate spline

ASJC Scopus subject areas

  • Agricultural and Biological Sciences (miscellaneous)
  • Anthropology

Cite this

Computerized restoration of nonhomogeneous deformation of a fossil cranium based on bilateral symmetry. / Ogihara, Naomichi; Nakatsukasa, Masato; Nakano, Yoshihiko; Ishida, Hidemi.

In: American Journal of Physical Anthropology, Vol. 130, No. 1, 05.2006, p. 1-9.

Research output: Contribution to journalArticle

Ogihara, Naomichi ; Nakatsukasa, Masato ; Nakano, Yoshihiko ; Ishida, Hidemi. / Computerized restoration of nonhomogeneous deformation of a fossil cranium based on bilateral symmetry. In: American Journal of Physical Anthropology. 2006 ; Vol. 130, No. 1. pp. 1-9.
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