•Conventional multi-unit abutments: Evidence was obtained from finite element analyses, stress distribution studies, and clinical reports assessing prosthesis success and biomechanical load transfer.

•Adjustable multi-unit abutments (Omnibut™): Regulatory documentation, including FDA 510(k) clearance (K242064), was reviewed regarding mechanical testing and safety evaluation.

•The Omnibut™ system was assessed using ISO 14801 dynamic fatigue testing, retention testing, and laboratory evaluation under simulated functional conditions.

•Range of angulation correction.

•Abutment selection requirements and efficiency of clinical procedures.

•Prosthesis fit and stress distribution.

•Range of clinical application and prosthetic system integration.

Results

•Conventional multi-unit abutments provide a single-piece gold standard design with fixed angulations (0°, 15°–17°, 30°); greater angulation increases stress concentration in implant components and cortical bone, while requiring multiple abutment selections and complex clinical procedures.

•Adjustable multi-unit abutments (Omnibut™) employ a two-component design permitting continuous correction up to 30°, demonstrate ISO 14801 fatigue equivalence, provide stable retention, reduce abutment selection demands. However, clinical outcome evidence remains limited.

Discussion

•Adjustable abutments enable clinical adjustment, support real-time correction and broaden application in compromised bone, divergent implant placement, and full-arch rehabilitation. However, clinical performance and possible complications remain uncertain.

•The need for a proprietary prosthetic screw for the final prosthesis may increase prosthesis cost compared to a standard prosthetic screw for conventional MUA’s.

Conclusion

 

References: 

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