Influence of Abutment Design on Biomechanical Behavior to Support a Screw-Retained 3-Unit Fixed Partial Denture

Area of Science:

• Biomaterials Science
• Dental Implantology
• Biomechanics

Background:

• Dental implants are crucial for supporting fixed partial dentures.
• Abutment selection impacts the biomechanical behavior of implant-supported prostheses.
• Morse taper implants offer a stable connection, but abutment design variations warrant investigation.

Purpose of the Study:

• To compare the biomechanical performance of Morse taper implants with CMN abutments versus miniconical abutments.
• To evaluate stress and strain distribution in screw-retained 3-unit fixed partial dentures supported by different abutments.
• To validate finite element analysis (FEA) models using in vitro strain gauge data.

Main Methods:

• In vitro testing using polyurethane blocks with Morse taper implants and either CMN or miniconical abutments.
• Strain gauge measurements were taken under a 300 N axial load.
• 3D finite element analysis was performed to simulate static structural behavior.

Main Results:

• In vitro strain gauge analysis showed no statistically significant difference in microstrain between CMN (645.3 ± 309.2 με) and MC (639.3 ± 278.8 με) groups (p = 0.879).
• FEA results also indicated no significant difference in microstrain between CMN (605.1 ± 358.6 με) and MC (598.7 ± 357.9 με) groups (p = 0.932).
• Computational models demonstrated good agreement with experimental data, validating the FEA approach.

Conclusions:

• Both CMN and miniconical abutments demonstrate comparable biomechanical behavior when supporting a 3-unit fixed partial denture on Morse taper implants.
• The choice between CMN and miniconical abutments may not significantly affect the mechanical stability of such restorations under optimal conditions.
• These findings support the clinical indication of both CMN and miniconical abutments for screw-retained fixed partial dentures in favorable scenarios.