Effect of different irrigant activation protocols on push-out bond strength

Area of Science:

• Endodontics
• Dental Materials Science
• Biomaterials Engineering

Background:

• Effective smear layer removal and irrigant activation are crucial for optimal adhesion in endodontic post restorations.
• Various activation techniques exist, but their comparative efficacy on fiber post bond strength requires further investigation.

Purpose of the Study:

• To evaluate and compare the push-out bond strength of fiber posts using different final irrigant activation protocols.
• To determine the most effective irrigant activation method for enhancing the bond strength of fiber posts to dentin.

Main Methods:

• Thirty-two human maxillary central incisors were instrumented, obturated, and post-space prepared.
• Roots were divided into eight groups, subjected to different final irrigant activation protocols including conventional syringe irrigation, passive ultrasonic irrigation, apical negative pressure, and various laser activations (Diode, Nd:YAG, Er:YAG, PIPS™).
• Fiber posts were luted, specimens sectioned, and push-out bond strength was tested and analyzed.

Main Results:

• Smear layer removal significantly increased bond strength compared to the control group.
• The Photon-Induced Photoacoustic Streaming (PIPS™) laser-activated irrigation group exhibited the highest push-out bond strength.
• Higher bond strength was observed in the coronal root region compared to the apical region.

Conclusions:

• Photon-Induced Photoacoustic Streaming (PIPS™) laser-activated irrigation is a highly efficient final irrigant activation protocol.
• This technique significantly improves the push-out bond strength of fiber posts, offering a promising approach for endodontic treatment.
• The coronal region of the root demonstrates superior bond strength compared to the apical region.