Accuracy (trueness and precision) of 3-dimensional virtual patients: An in vitro investigation of different facial scanners and digital integration techniques.

OBJECTIVES

To investigate the influence of different facial scanners and integration approaches on the accuracy of virtual dental patients (VDPs).

METHODS

Forty VDPs were generated using a head mannequin and two facial scanners: 1) an industrial scanner and 2) a smartphone scanner. For each scanner, two integration methods were applied: 1) integration by virtual facebow scan and 2) integration by nose-teeth scan. This resulted in four VDP groups, with ten repetitions for each group (n = 10). A cone beam computed tomography (CBCT) scan of the mannequin served as the reference. The linear deviations of the maxillary arches at teeth #16, #21, and #26, as well as the angular deviations of the occlusal planes, were measured to assess accuracy.

RESULTS

No significant trueness differences were found between the scanners (p = 0.78 for tooth #16, p = 0.84 for tooth #21, p = 0.35 for tooth #26, p = 0.18 for angular deviations) or between the integration techniques (p = 0.42 for tooth #16, p = 0.29 for tooth #21, p = 0.76 for tooth #26, p = 0.61 for angular deviations). In terms of precision, the industrial facial scanner demonstrated superior outcomes (p < 0.001 for teeth #16, #21, #26, and angular deviations). No significant precision differences were found between the two integration techniques for teeth #16 (p = 0.17) and #26 (p = 0.25), or for angular deviations (p = 0.27); however, the nose-based integration technique showed higher precision for tooth #21 (p = 0.01).

CONCLUSIONS

The smartphone-based facial scanner exhibited trueness comparable to that of the industrial facial scanner, though with reduced precision. The nose-based integration technique demonstrated better accuracy compared to the virtual facebow-based technique.

CLINICAL SIGNIFICANCE: The smartphone-based facial scanner achieves trueness comparable to the industrial facial scanner for VDP integration. Additionally, the nose-based integration technique offers a viable alternative to the virtual facebow-based approach, with a simplified scanning and integration process.