Visualization of x-ray microtomography data for a human tooth atlas

摘要

Three-dimensional x-ray microtomography is used in this work to assess the internal morphology and mineral density of human tooth specimens. Of particular interest is the demonstration of the character of the distal root canal morphology, which can be as small as 10 microns. Human teeth are individually embedded in a low atomic number material. Each tooth is then identically scanned on an advanced design bench-top cone-beam microtomography system under controlled conditions. The specimens are scanned using an 80 kVp technique and a CsI(Tl) scintillator mounted via a taper to a thermoelectrically cooled CCD camera with an overall nominal pixel size of 15 microns at the plane of the specimen. Scanning a ruby sphere phantom independently assessed the resolution of the system. The full width at half-maximum of the plane spread function is nominally 53 microns in the axial direction and 60 microns in the transverse plane. The visualization of the x-ray data consists of several complimentary techniques, including a three-dimensional stack of the reconstructed tomogram slices with 30 micron reconstruction voxel, a 360 degree rotating view of the tooth comprised from a sequence of projection images processed for detail contrast enhancement and edge restoration, and a surface model of each tooth. In total, 237 human teeth representing multiple samples of each of the varied tooth types have been individually scanned, analyzed, and visualized to date. The set of tooth data is being compiled into a comprehensive human tooth atlas, which is to be made available on CD for students and investigators as a resource for anyone studying tooth morphology and mineralization.