Material and Methods: Dental impressions were taken from the maxilla as well as from the mandible of 17 patients twice with a polyethergum impression-material, so each jaw was displayed two times. Stone replica impressions were analyzed by a computer-driven laser which created three-dimensional computerized surface models of the teeth. A standard computer algorithm was used to superimpose the corresponding model images. Each tooth was scanned separately from buccal, occlusal and oral. The percentage of agreement between the two measurements was taken as reliability.
Results: An overall agreement of 90,67±1,85% was achieved. There were no differences between the maxillary (90.09±3.10%) and the mandible (90.66±3.66%) nor between the buccal/lingual aspects of the teeth (90.81±2.64%) compared to the occlusal tooth surfaces (90.57±2.23%).
Conclusion: Although no specific aids were used to standardize the impression process and to support the matching process of the two digital 3D images, the agreement between the two measurements was higher than 90% for all tooth surfaces and locations.