Influence of multiple use of titanium and PEEK scan bodies on scan precision after sterilization and thermal...

We evaluated the influence of multiple uses of scan bodies after reprocessing cycles-steam sterilization and thermal disinfection-on the precision of implant position transfer.

Six mandibular models with two implants in regions 34 and 36 were fabricated. The implants were scanned with an intraoral scanner using pairs of titanium (SB_T_Pr) and polyether ether ketone (PEEK) (SB_P_Pr) scan bodies according to the manufacturers' recommendations. The scan body group underwent up to 15 standardized reprocessing cycles. The unreprocessed titanium group (SB_T_NPr) served as a control. Three-dimensional deviations (R) between the implant positions were calculated from the scanned STL datasets and statistically analyzed (P < 0.05).

A preliminary investigation demonstrated that 15 cycles of screwing in and out of the titanium or PEEK scan bodies did not influence subsequent measurements (P = 0.129, P = 0.215). The mean ΔR values were 38.9 ± 18.7 µm for SB_T_NPr and 42.6 ± 19.5 µm for SB_T_Pr. No significant differences in precision were found between the unprocessed and reprocessed titanium scan bodies within 15 cycles (P = 0.174). The mean ΔR value for SB_P_Pr was 27.1 ± 12.5 µm. In contrast, the PEEK scan bodies consistently showed significantly lower deviations than the titanium scan bodies (P < 0.001).

PEEK scan bodies demonstrate higher precision but may be limited by lower mechanical stability and their single-use concept. Titanium scan bodies, although slightly less precise, have proven to be mechanically robust and suitable for multiple reuses after the conducted reprocessing. Further clinical studies with extended re-processing cycles are required to confirm these findings.