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Updated: Jun 28, 2026
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Published on: April 11, 2025
Rotational Load Fatigue Performance of Implants with Cylindrical and Conical Internal Cam-Groove Connections
Summary
Narrow CAM implants showed significantly poorer rotational load fatigue performance. Failures occurred below the bone level, posing clinical retrieval challenges.
Area of Science:
- Biomaterials Science
- Dental Implantology
- Mechanical Engineering
Background:
- Dental implant-abutment complexes have evolved, with brands refining designs over time.
- Understanding the mechanical performance of different implant-abutment configurations is crucial for long-term success.
Purpose of the Study:
- To investigate the rotational load fatigue performance of narrow, regular, and wide diameter implants.
- To compare cylindrical (CAM) and conical (CNL) internal cam-groove configurations under fatigue loading.
Main Methods:
- Six groups of implant-abutment assemblies (CAM and CNL, narrow/regular/wide diameters) were tested (n=5 per group).
- A rotational load fatigue machine applied a 35Ncm bending moment at 12 Hz until failure or 5x10^6 cycles.
- Failures were analyzed using SEM to determine fracture patterns.
Main Results:
- Only the narrow diameter cylindrical CAM implants (CAM33) experienced failures (5 out of 30 samples).
- Failures in CAM33 occurred below the anti-rotational features, affecting abutments, screws, and implants.
- All other groups, including regular/wide CAM and all CNL implants, reached the fatigue limit without failure.
Conclusions:
- The CAM33 group demonstrated significantly poorer rotational load fatigue performance compared to other tested configurations.
- Failures below the simulated bone level in CAM33 implants present potential clinical difficulties for retrieval and replacement.
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