Assessment of the effectiveness of intraoral scanning in patients with maxillary defects: a clinical study

The aim was to evaluate the accuracy of an intraoral scanner in obtaining digital scans of maxillary defects and adjacent tissues to fabricate obturator prostheses.

Ten randomly selected patients who required an obturator prosthesis after maxillary resection underwent both conventional and digital impressions. Conventional impressions were obtained using traditional methods, and cast models were prepared. The cast models were digitized using a reference scanner in STL format. For the digital impression group, an intraoral scanner (Trios 5; 3Shape) was used for digital scans and virtual models were created. The data of both groups were analyzed by superimposing predetermined points using reverse engineering software (Geomagic Control; 3D Systems).

No significant deviations from normality (P > 0.05) were found in the predetermined points of the residual hard tissue in the STL data. No interaction was observed between the hard tissue components and the impression techniques used. However, accuracy significantly varied between overlapped points in defect parts across the two impression methods (P = 0.028).

The use of an intraoral scanner for digitally scanning maxillary defects was less effective than conventional impression methods, performing adequately with shallow defects but facing challenges with deeper cavities. It is essential to advance these techniques and conduct clinical studies with larger patient groups to gain broader acceptance of digital impression methods for routine clinical use, particularly for deep defects.