In a research project for the testing of dental wear in connection with the introduction of new dental materials (financed by the Norwegian Directorate for Health and Social Welfare), SINTEF was asked to build a measurement device for determining the 3D shape of dental impressions, comparing impressions of the same tooth taken at different times, and determining the wear. The SINTEF solution was chosen ahead of commercial laser scanning instruments because it could readily be adapted to give the micrometer precision that characterises dental wear. 

The instrument has since found application in studying the reproducibility of chair-side procedures for preparing dentures, again an application requiring high precision.

The chosen method, structured light projection, allows fast and robust shape measurements with a high resolution and accuracy. The method can be applied to a wide variety of objects in different sizes. In this project, SINTEF designed and built a device based on a data projector and video camera, with a special manipulator for the impressions to be measured. The measurements are controlled by the HoloVision software.

Download fact sheet for more information about structured light projection.