Does abutment preparation affect abutment screw joint stability? An in vitro study.

Area of Science:

• Dental Implantology
• Biomaterials Science
• Prosthodontics

Background:

• The stability of abutment screw joints is crucial for dental implant success.
• The impact of abutment preparation on screw joint stability remains unclear.

Purpose of the Study:

• To investigate the effect of laboratory-simulated abutment preparation on the reverse torque value (RTV) of dental implant abutment screws.
• To compare the stability of abutment screw joints between two different implant manufacturers after preparation.

Main Methods:

• Sixty implants and abutments from two manufacturers were divided into groups based on remaining wall thickness (control, 0.4 mm, 0.6 mm).
• Abutments were torqued, prepared using a milling system, re-torqued, and then tested for RTV.
• Statistical analysis included ANOVA and t-tests; scanning electron microscopy examined screw designs.

Main Results:

• A significant difference in RTV was observed between manufacturers (BioHorizons vs. NucleOSS).
• For NucleOSS implants, preparation significantly reduced RTV, particularly with a 0.6 mm wall thickness.
• Manufacturer and preparation showed a significant relationship with RTV.

Conclusions:

• Abutment preparation does not compromise the screw joint stability of BioHorizons implants.
• Abutment preparation can negatively affect the screw joint stability of NucleOSS implants.
• Differences in screw head and thread design between manufacturers may influence stability.