Pull-off resistance of a screwless implant-abutment connection and surface evaluation after cyclic loading

J Adv Prosthodont. 2021 Jun;13(3):152-159. doi: 10.4047/jap.2021.13.3.152. Epub 2021 Jun 25.

Abstract

Purpose: The aim of this study was to investigate to what extent cyclic load affects the screwless implant-abutment connection for Morse taper dental implants.

Materials and methods: 16 implants (SICvantage max) and 16 abutments (Swiss Cross) were used. The screwless implant-abutment connection was subjected to 10,000 cycles of axial loading with a maximum force of 120 N. For the pull-off testing, before and after the same cyclic loading, the required force for disconnecting the remaining 6 implant-abutment connections was measured. The surface of 10 abutments was examined using a scanning electron microscope 120× before and after loading.

Results: The pull-off test showed a significant decrease in the vertical force required to pull the abutment from the implant with mean 229.39 N ± 18.23 before loading, and 204.30 N ± 13.51 after loading (P<.01). Apart from the appearance of polished surface areas and slight signs of wear, no visible damages were found on the abutments.

Conclusion: The deformation on the polished abutment surface might represent the result of micro movements within the implant-abutment connection during loading. Although there was a decrease of the pull-off force values after cyclic loading, this might not have a notable effect on the clinical performance.

Keywords: Dental implant; Dental implant-abutment connection; Morse taper dental implant-abutment connection; Wear.