Clinical Evaluation of a Hyperbolic Paraboloid Triple-Abutment on Morse Taper Dental Implants

This prospective clinical study aims to evaluate the clinical and radiographic performance of an innovative triple-abutment (TA) system with hyperbolic paraboloid geometry installed on Morse taper dental implants. The abutment system is designed to support three adjacent crowns on a single implant through a fully curved, passive, non-welded configuration, with the objective of optimizing biomechanical load distribution and preserving peri-implant tissue stability. The concept is based on principles of mechanobiology, mechanotransduction, and biotensegrity, integrated within the framework of Optimized Biodynamic Peri-Implant Tissue (BOPiT).

Thirty systemically healthy adult participants presenting with three adjacent missing teeth will be enrolled. Implant placement will be performed following conventional surgical protocols. After surgery, a healing period of approximately three months will be allowed to achieve osseointegration prior to prosthetic loading. Subsequently, metal-ceramic fixed prostheses will be cemented over triple-abutment components. All surgical and prosthetic procedures will be conducted by a single experienced operator to ensure standardization.

Clinical and radiographic evaluations will be performed at two predefined follow-up timepoints: T1, corresponding to 3-4 months after prosthetic loading, and T2, corresponding to 12-18 months after prosthetic loading. The primary outcome measure will be marginal bone level change, assessed on standardized periapical radiographs obtained using the parallel technique with controlled calibration, and measured at the mesial and distal aspects of each implant.

Secondary outcome measures will include probing depth, bleeding on probing, plaque index, keratinized mucosa height, and patient-reported satisfaction assessed using a visual analog scale (VAS). Clinical maintenance visits will be scheduled every four months between T1 and T2 to monitor peri-implant health and prosthetic performance.

Statistical analyses will be conducted using parametric methods appropriate for repeated measures, with strategies to account for potential within-subject correlation in participants receiving more than one implant. Adverse events and biological or prosthetic complications will be recorded throughout the study period. The risks associated with participation are minimal and comparable to those of conventional implant-supported rehabilitations. In the event of complications, the triple-abutment system may be replaced by conventional abutments according to clinical judgment.

This study seeks to provide clinical evidence regarding the biomechanical and biological behavior of the triple-abutment system when applied to Morse taper implants, potentially supporting a more conservative and cost-effective rehabilitative approach by enabling the restoration of three adjacent teeth with a single implant while maintaining peri-implant tissue stability.

Inclusion criteria

• Adults aged ≥ 18 years.
• Systemically healthy as determined by medical history and clinical assessment.
• Non-smokers (no tobacco use).
• Able and willing to comply with study visits and maintenance program, and provide written informed consent.

Exclusion criteria

• diabetes mellitus (any type) or uncontrolled systemic disease.
• current or recent tobacco/nicotine use
• bisphosphonates or other antiresorptives,
• immunosuppressive therapy,
• osteoporosis
• pregnancy or lactation.