Reviving the dinosaur: virtual reconstruction and three-dimensional printing of a dinosaur vertebra.

PURPOSE To demonstrate the feasibility of using computed tomography (CT) to confirm the identity of an unprepared fossil and to use the CT dataset to separate the fossilized bone from its surrounding sediment matrix and produce a three-dimensional (3D) print. MATERIALS AND METHODS The examined object was a plaster jacket containing an unprepared fossil. CT was performed with a 320-section multidetector unit. A marching cube-based method was used to transform the voxel CT dataset into triangle-based, editable geometry. Then, a comprehensive postprocessing step was performed to isolate the geometry of the vertebra from its surrounding fossilized matrix. Finally, the resulting polygon mesh describing only the vertebra was used for a physical 3D reconstruction by using a selective laser sintering machine. RESULTS The CT examination provided enough data to assign the fossil to the genus Plateosaurus. In addition, much valuable information about the fossil has been gained-in particular the visualization of multiple fractures and the destruction of the anterior rim of the vertebral body. Finally, the results show that the 3D print generated, including the fractures and the anterior destruction, may be considered an accurate copy of the bone with the unprepared fossil. CONCLUSION The authors demonstrated the feasibility and potential utility of combining CT with 3D printing, providing a nondestructive method to future paleontologists.