Maximum dislodging forces of implant overdenture stud attachments.

Area of Science:

• Dental Implantology
• Prosthodontics
• Biomaterials Science

Background:

• Implant-supported overdentures are increasingly used for patient rehabilitation.
• Various attachment systems are available, each with unique retentive properties.
• Understanding attachment performance is crucial for successful treatment outcomes.

Purpose of the Study:

• To compare the retention and stability of six different implant attachments.
• Evaluate Nobel Biocare standard ball (NBS), Nobel Biocare 2.25-mm-diameter ball (NB2), Zest Anchor (ZA), Zest Anchor Advanced Generation (ZAAG), Sterngold ERA orange (SEO), and Sterngold ERA white (SEW) attachments.
• Determine the most retentive attachment under simulated functional forces.

Main Methods:

• A test model with two Brånemark System implants was used.
• Attachments were tested in a denture-like housing subjected to dislodging tensile forces.
• Forces were applied vertically, obliquely, and anterior-posteriorly using an Instron machine.
• Peak load measurements determined the maximum dislodging force for each attachment.

Main Results:

• The ZAAG attachment demonstrated the highest retention under vertical forces (37.2 ± 5.5 N).
• Under oblique forces, ZAAG was also the most retentive (27.2 ± 4.2 N).
• For anterior-posterior forces, NBS showed the highest retention (34.6 ± 18.8 N), not statistically different from NB2 and ZAAG.

Conclusions:

• Attachment selection for implant-retained overdentures can be guided by desired retention levels.
• The ZAAG and NBS attachments exhibit superior retentive properties in specific functional directions.
• This study provides empirical data to aid clinicians in choosing appropriate implant attachments.