Fatigue and microgap behaviour of a three-unit implant-fixed dental prosthesis combining conventional and dynamic abutments

Abstract

This is an in vitro study composed by a fatigue test followed by an optical microscopy analysis. Dynamic abutments concept, recently introduced on screw-retained implant dental prosthesis, consists on the screw channel customisation according to the individual needs of each rehabilitation. Geometry and tightening torque differences advise the assessment of their mechanical performance. Clarify whether the combination of dynamic and conventional abutments in a three-unit implant-fixed prosthesis has detrimental effects either on the mechanical performance under cyclic loading or on the implant-abutment microgap dimensions. The fatigue test was performed in agreement with the ISO standard 14801. Then on the samples that resisted 5 million cycles, the implant-abutment microgap was measured on dynamic and conventional abutments using optical microscopy. Two unloaded samples were used as control group. The samples supported a load of 1050 N. The implant-abutment microgap measurement did not show statistically significant differences (p = .086) between loaded and unloaded groups, but the loaded conventional abutments showed a significant lower implant-abutment microgap (p = .05) than the loaded dynamic abutments. The combination of conventional and dynamic abutments do not seem to produce a decrease in fatigue resistance to a level below the mastication forces or an increase in the joint dimensions.

Keywords:

• Dynamic abutments
• fatigue test
• microgap

Acknowledgements

The authors gratefully acknowledge the Avinent® Implant Company for their collaboration in providing the specimens tested.

The authors also acknowledge the INEGI for the preparation of the necessary tailor-made solutions to respect the ISO standard 14801.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The study was supported in part by SciTech - Science and Technology for Competitive and Sustainable Industries, and the R&D project was cofinanced by the North Portugal Regional Operational Program [NORTE2020] and the European Regional Development Fund (FEDER).