Accuracy evaluation of dual-function scan body for recording complete arch implant-supported prostheses

Scan bodies that enable the reduction of prosthetic components while maintaining accuracy for digital framework planning are limited and require further investigation.

The purpose of this in vitro study was to evaluate the accuracy (precision and trueness) of a dual-function scan body in capturing the angulation and distances of multiple implants in completely edentulous arches.

Four implants (CM 4.3×10 mm) were placed in a 3-dimensionally (3D) printed mandibular model, from which a master gypsum cast was fabricated. This cast served as the basis for fabricating an interim prosthesis using conventional techniques. The master cast was scanned with a laboratory scanner using a commercial scan body (LS, control group) and a dual-function scan body in its intraoral configuration (B-IS), while the interim prosthesis was digitized via reverse extraoral scanning (B-RS). Interimplant distances and 3D angulations (X, Y, and Z axes) were evaluated using an inspection software program (GOM Inspect). Precision was descriptively assessed using standard deviation and coefficient of variation, while trueness was evaluated through directional delta values between laboratory and Bioscan scans using paired t tests (α=.05).

Interimplant distance measurements demonstrated comparable precision among scanning methods, with no relevant differences in variability. Trueness analysis revealed similar distance deviations between B-IS and B-RS scanning. Implant angulation measurements also exhibited comparable precision across the 3D axes. Regarding trueness, significant differences between B-IS and B-RS were observed for the X axis overall, as well as for the Z axis and angular planes (XZ and YZ) of one implant (P<.05).

The dual-function scan body demonstrated adequate precision and trueness in capturing implant distance and angulation, with localized limitations in the trueness of vertical and horizontal angulations.