3D Shape Measurement of Dental Casts Using Medical X-ray CT

Investigation of dosimetric characteristic of NIPAM polymer gel using x-ray CT

Introduction: Polymer gel dosimeters contain chemical materials sensitive to the radiation which are polymerized by the radiation as a function of absorbed dose. So information of spatial dose distribution can be extracted by imaging from irradiated gel. Among imaging techniques, computed tomography (CT) poses as an attractive method because of practical advantages such as acce...

Bayesian inversion method for 3D dental X-ray imaging

Diagnostic and operational tasks in dentistry require three-dimensional (3D) information about tissue. A novel type of low dose dental 3D X-ray imaging is considered. Given projection images taken from a few sparsely distributed directions using the dentist’s regular X-ray equipment, the 3D X-ray attenuation function is reconstructed. This is an ill-posed inverse problem, and Bayesian inversion...

3D X-ray CT for BGA/CGA Workmanship Defect Detection

Flexible 3D shape measurement using projector defocusing: extended measurement range.

A recently proposed flexible 3D shape measurement technique using a defocused projector [Opt. Lett. 34, 3080 (2009)] shows great potential because of its elimination of projector's gamma calibration. However, it cannot handle step-height surfaces. I present here a technique to extend its measurement range to an arbitrary shape by integrating a binary coding method. A computational framework is ...

Direct 3-D morphological measurements of silicone rubber impression using micro-focus X-ray CT.

Three-dimensional computer models of dental arches play a significant role in prosthetic dentistry. The microfocus X-ray CT scanner has the advantage of capturing precise 3D shapes of deep fossa, and we propose a new method of measuring the three-dimensional morphology of a dental impression directly, which will eliminate the conversion process to dental casts. Measurement precision and accurac...