Abstract:

Objective　To develop a computer assisted CTscanning system for 3D dental cast measurement and to study its re- liability.Methods　20 dental stone castswere scanned by helical CTand captured a series digital sliced radiographs of them.The program which was developed byVisual C 6.0 language and run underthe Windows surroundings rebuiltthe 3D graphics and mea- sured the coordinate of the dental cast. These dental castswere scanned and measured totestthe reliability of the system, contrast- ingwith manual measurement.Results　There was no significant difference between 3D CT scanning and manual measurement (P>0·05).Conclusion　The system is a valuable computer assisted systemfor clinical diagnosis and treatment ofmalocclusion.

Key words: dental cast, computed tomography, three-dimensional measurement