Research Information System
European Association for Osseointegration, Geneve, Switzerland, 29 September - 01 October 2022, vol.33, pp.9-10
Emre Diker1,*; Hakan Terzioğlu1; Diogo Gouveia2; Jeremy Seidt3; Burak Yılmaz4
1Department of Prosthodontics, Ankara University Faculty of Dentistry, Ankara, Turkey; 2Division of Restorative and Prosthetic Dentistry, The Ohio State University College of Dentistry; 3Department of Mechanical and Aerospace Engineering, The Ohio State University College of Engineering, Columbus, USA; 4Department of Reconstructive Dentistry and Gerodontology, University of Bern, School of Dental Medicine, Bern, Switzerland
Background: Digital impressions for single implants have shown to be comparable with traditional impressions and are comfortable for patients because they eliminate the need for traditional impression materials. As the scanner technologies have improved, the design of scan bodies has evolved and their use has increased. Intraoral scan bodies can be made of monolithic materials or by a combination of different materials, such as titanium, PEEK, aluminum alloy and various resins.
Aim/Hypothesis: To evaluate whether 3-dimensional displacements occur with scanbodies during screw tightening when different materials (Ti and PEEK) and torque values are used, and after sterilization, using digital image correlation analysis.
Material and Methods: Two implants (MPS, Medentika, Straumann, DE) were clamped to a table. PEEK (Zimmer Biomet, USA) and Ti (MPS, Medentika, Straumann, DE) scan bodies (n = 10) were initially tightened with 5 Ncm torque by using a torque measuring instrument to ensure that the target torque was transmitted and controlled, and the first displacement measurements were made simultaneously and recorded by using Digital Image Correlation (DIC) analysis. The displacement measurements (initial) were repeated after 10 and 15 Ncm torque were applied. Scanbodies were ultrasonically cleaned and sterilized 25 times (Statim 5000S, CA) at 134 °C for 3.5 mins. Then, 10 and 15 Ncm torque were re-applied and displacements were remeasured (after sterilization). Data were processed by IBM SPSS version 26. Mann-Whitney U test was used to compare Ti and PEEK groups and Wilcoxon Signed Ranked test was used for the values before and after the processes.
Results: For displacements in mesiodistal direction, significant differences were found between Ti and PEEK groups (p < 0.001). When initial and after sterilization values were compared, no difference was observed within Ti groups (p > 0.05), but significant differences were seen in PEEK groups (p = 0.028 for 10 Ncm and p = 0.002 for 15 Ncm).
In vertical direction, a significant difference was found between Ti and PEEK groups with 15 Ncm torque (p = 0.033 and p = 0.001). When initial and after sterilization values were compared, significant difference was found in 10 Ncm groups (p = 0.019), and in 15 Ncm in PEEK group (p = 0.028).
In buccolingual direction, significant effect of material was found when 10 Ncm (initial) (p = 0.001) and 15 Ncm (both initial and after sterilization) torque were applied (p = 0.015). When initial and) and after sterilization were compared, significant differences were found in PEEK groups (p = 0.044 for 10 Ncm and p = 0.351 for 15 Ncm).
Conclusion and Clinical implications: Material and sterilization made a difference in axial displacements of scan bodies. One-piece Ti scan body or scan bodies with Ti implant connections should be preferred instead of scan bodies made of entirely PEEK for lower scanbody displacements.
Care should be taken when selecting a scan body, as axial displacement may affect the occlusal and proximal contacts of implant crowns.