Shear bond strength between veneering composite and PEEK after different surface modifications

Area of Science:

• Biomaterials Science
• Dental Materials
• Surface Engineering

Background:

• Polyetherketone (PEEK) is a high-performance polymer used in dental applications.
• Achieving durable bonds between PEEK and dental composites is crucial for restoration longevity.
• Various surface treatments exist, but their efficacy on PEEK bonding requires detailed investigation.

Purpose of the Study:

• To evaluate the impact of diverse surface treatments and conditioning protocols on the shear bond strength (SBS) between PEEK and composite materials.
• To determine the optimal surface preparation methods for enhancing PEEK-composite adhesion.

Main Methods:

• 570 PEEK surfaces underwent treatments: untreated, etching, air-particle abrasion, or silica-modified alumina oxide activation.
• Surface roughness was quantified. Composite cylinders were polymerized onto treated PEEK surfaces.
• Shear bond strength (SBS) was tested after 24 hours, 90 days of water storage, and 12,000 thermal cycles (5°C/55°C).

Main Results:

• Surface treatments significantly altered roughness, with etching causing the most substantial increase (up to 6.76 μm).
• SBS values varied widely (0.0–23.2 MPa at baseline).
• After aging (water storage or thermal cycling), several systems maintained SBS > 5 MPa, with some exceeding 10 MPa, indicating improved durability.

Conclusions:

• Surface cleaning and roughening are essential for successful PEEK-composite bonding.
• Surface conditioning prior to bonding is critical for achieving optimal adhesion.
• Combining surface treatments with opaque application can further enhance SBS.