Effect of Repeated Use of Different Types of Scan Bodies on Transfer Accuracy of Implant Position.

Statement of the problem: Some components of implant treatment are reusable. Therefore, possible changes during fixation, removal, and sterilization process should be tested. Many studies have examined the reuse of implant parts, but the impact of repeated use of scan bodies on the accuracy of implant position has not been well investigated.

Purpose: The aim of this in vitro study was to compare the effect of repeated use of two different types of scan bodies on the accuracy of implant position.

Materials and method: In this in vitro experimental study, two acrylic resin maxillary models, each with two implant analogues inserted at the site of missing first and second molars were used. Two types of scan bodies including titanium and polyetheretherketone (PEEK) were used for digital impression. Then they were ten times removed and autoclaved for sterilization. The first scan was considered as a reference to be compared with the other next nine scans. Values of linear distance between two scan bodies, diameter changes of each scan body, and three-dimensional linear displacement (ΔR) were measured. These values were compared between the two types of scan bodies using t-test (α=.05).

Results: There was significant difference between titanium and PEEK scan bodies regarding inter-implant distance variation (p=.006) and diameter change (p< .001) in repeated use. However, for the ΔR, there was no significant difference between them (p= 0.759).

Conclusion: The results demonstrated that type of scan body could affect the accuracy of implant position transfer after repeated use. PEEK scan body performed better after 9 cycles of reuse in comparison with titanium scan body.