Effects of the intraoral scanner and implant library on the trueness of digital impressions in the full-arch implant scan: A comparative in vitro study.

OBJECTIVE

To evaluate the effect of intraoral scanners (IOSs) and implant libraries (ILs) on the trueness of digital impressions for the fabrication of implant-supported full-arch (FA) prostheses.

METHODS

A stone cast of an edentulous maxilla with 6 implant analogues and cylindrical scanbodies (IPD ProCam®, Matarò, Barcelona, Spain) was probed using a coordinate measuring machine to capture a reference model (RM). The cast was mounted on a mannequin and scanned with 3 different IOSs (iTERO Element 5D Plus®, Align Technologies, San José, CA, USA; IS 3800®, Dexis, Quackertown, PN, USA; and i-700®, Medit, Seoul, South Korea). Ten scans were performed by an experienced operator using each IOS, first capturing only the occlusal surfaces, then the buccal and finally the palatal surfaces (less than 45 s per scan). In each scan, the meshes of the SBs were replaced by the corresponding IL file, with and without increment, to obtain the best correction for the mesh growth. The positions of the SBs in each file were compared with those in the RM, to evaluate the linear and cross distances between them. The final outcome was the trueness of the different IOSs, evaluating the effect of using different ILs on the quality of the impressions.

RESULTS

Significant differences were found between the different IOS scans and the RM, and among the different IOSs, in the different segments. The correction of the mesh growth through incremental ILs did not affect the final trueness of the IOS scans.

CONCLUSIONS

Different levels of trueness were found among the IOSs evaluated, in the different scan segments, but with the cylindrical SBs used herein, the correction of the mesh growth with incremental ILs did not affect the final quality of the digital impressions.

STATEMENT OF CLINICAL RELEVANCE

There are still errors with IOS in the FA impressions. IOS have an effect on the quality of the digital impressions, and apparently the library has not, with purely cylindrical SBs: further studies are needed to confirm this aspect.