Dynamic fatigue resistance of implant–abutment junction in an internally notched morse‐taper oral implant: influence of abutment design

Abstract

Purpose: To compare dynamic fatigue resistance of one- and two-piece abutments connected to internally notched morse-taper oral implants. Material and methods: Sixteen synOcta® ITI® implants were tightened into two metal models. SynOcta® abutments for cement-retained restorations and solid abutments were divided into two equal groups and were torque-tightened into the implants. Each implant received a cement-retained crown. Cyclic dynamic axial and lateral peak loads of 75±5 N were applied on the implants for a duty of 500,000 cycles at 0.5 Hz, and at an angle of 20°. Prior to the experiments and at each 100,000 cycles of loading, periotest values (PTVs) were measured. Removal torque values (RTVs) of the abutments were also measured with a custom-made torque device at the termination of the experiment. Results: All abutments and implants were clinically immobile and without any signs of mechanical failure. The final PTVs for both abutments were similar and the difference between groups was insignificant (P>0.05). The RTVs of solid abutments were significantly higher than synOcta® abutments (P<0.05). Conclusion: Predictable long-term clinical results can be achieved with solid abutments and synOcta® abutments for cement-retained restorations. Solid abutments possess higher removal torque resistance than synOcta® abutments when connected to synOcta® ITI® implants.