Push-out Bond Strength of Fiber Posts in Long-Term Hypobaric Pressure Changes

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Endodontics

Background:

• Fiber post restorations are crucial in endodontics.
• Understanding cementation techniques is vital for long-term restoration success.
• Environmental pressure changes can impact dental material performance.

Purpose of the Study:

• To evaluate the bond strength of fiber posts.
• To compare different resin cement mixing methods.
• To assess insertion techniques under simulated hypobaric pressure changes.

Main Methods:

• 42 decoronated teeth were used.
• Fiber posts were cemented with hand-mixed and auto-mixed resin cements.
• Cementation involved endodontic files, dual-barrel syringes, or root canal tips.
• Samples underwent 90 cycles of hypobaric pressure exposure.
• Push-out bond strength was measured using a Universal Testing Machine.

Main Results:

• Auto-mixed resin cement with a root canal tip yielded the highest bond strength.
• Hypobaric pressure significantly reduced bond strength compared to ambient pressure.
• Adhesive failure between dentin and cement was the most common failure mode.

Conclusions:

• Auto-mixed resin cements combined with a root canal tip provide optimal fiber post retention.
• Clinicians should consider cementation techniques for patients exposed to hypobaric conditions.
• Further research into biomaterial behavior under environmental stress is warranted.