Objectives: The aim of this study was to evaluate the accuracy of measurements made on intraoral directly scanned 3D digital models compared to stone model measurements using two approaches (from occlusal and labial/buccal aspect).
Materials and methods: 3D intraoral digital models and stone models were made for each patient in a sample consisted of twenty randomly selected orthodontic patients. Mesiodistal teeth width and arch perimeter measurements on the digital models taken by occlusal and labial/buccal approaches were compared with those on the corresponding stone models.
Results: There was no statistically significant difference, regarding the mesiodistal width measurement of all the teeth, between digital and stone models when using both measuring approaches. However, there was a significant increase in digital measurements than manual measurements for maxillary posterior segments and for maxillary total arch perimeter only when measured by occlusal approach. While all arch perimeter measurements (segmented and total) showed a significant increase in digital measurements when compared those taken manually, in both arches, when measured by labial/buccal approach .
Conclusions: The mesiodistal width measurements of each tooth obtained with 3D intraoral chairside digital models and CEREC Premium software by using occlusal or labial/buccal approaches are considered both accurate and reliable. Regarding the arch perimeter measurements, the occlusal measuring approach is better and more reliable than the labial/buccal approach for both stone and 3D digital models. The digital models are clinically acceptable and may be used as an alternative to gold standard stone models.