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第33巻 第1号 >

Construction method of a tooth crown model using data generated by micro-focus CT ― Voxel models of anterior and premolar teeth ―

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Please use this identifier to cite or link to this item:http://hdl.handle.net/2115/52156

Title: Construction method of a tooth crown model using data generated by micro-focus CT ― Voxel models of anterior and premolar teeth ―
Authors: Ueda, Yasuo Browse this author
Kobayashi, Yuya Browse this author
Takamichi, Osamu Browse this author
Ohata, Noboru Browse this author
Keywords: Voxel Model
CAD/CAM
Micro-CT
Shape Measurement
Issue Date: Sep-2012
Publisher: 北海道歯学会
Journal Title: 北海道歯学雑誌
Volume: 33
Issue: 1
Start Page: 17
End Page: 23
Abstract: Currently, a number of dental CAD/CAM systems are in operation in Japan. Many of them adopt a non-contact optical system using a CCD camera and light patterns to measure the model teeth. One disadvantage of this method is that it is difficult to measure the parts in the shade. However, this problem can be solved if we can carry out measurements using 3D CT. In this study we have examined how to construct a 3D model of a tooth crown shape using micro-CT data. An R_mCT2 micro-CT manufactured by Rigaku Corporation was used under maging conditions of FOV10(φ10 mm×H10 mm), 90 kV tube voltage and 160 μA tube current. Basic study models manufactured by KaVo Dental GmbH were used in the imaging, which was carried out in two phases, as the size of the artificial teeth was greater than that of the FOV. The image data was output in 512 slices in the form of DICOM files, and transferred to a personal computer. We examined the CT values of all the voxels of all images using software we developed ourselves. Based on the results, we determined the threshold by comparing the distribution of the CT values of the artificial teeth area with those of the remaining area in each image, and extracted the shape of the artificial tooth by binarizing the image. The separate image data was aligned by detecting the location of the closest number of pixels to the binarized image. Artifacts included in the images were removed manually and the completed voxel data output in DICOM format. Shape was confirmed using free DICOM viewer software(OsiriX). As a result, the margin of error for superimposing the contour shape of the split image data is approximately one voxel(± 20 μm). Artifacts were seen in 20 to 50 slices of the binarized images but because they were minor, we were able to process the images quickly and easily. In this study we were able to construct a high-resolution model of artificial teeth with relative ease. In future, if we can success in realizing low-cost, higher performance dental cone-beam CT, we will be able to use it to measure abutment teeth.
Type: article
URI: http://hdl.handle.net/2115/52156
Appears in Collections:北海道歯学雑誌 = Hokkaido Journal of Dental Science > 第33巻 第1号

Submitter: 上田 康夫

 

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