Impregnation by dentine bonding agents into instrumented root-face dentine

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Restorative Dentistry

Background:

• Effective sealing of instrumented root canal dentine is crucial for successful endodontic treatment.
• Dentine bonding agents (DBAs) are utilized to improve the adhesion of restorative materials to dentine.
• Understanding resin penetration into root dentine is vital for predicting long-term restoration success.

Purpose of the Study:

• To evaluate the penetration depth and density of unfilled resin into instrumented root-face dentine.
• To compare the efficacy of five commercially available dentine bonding agents in facilitating resin penetration.
• To investigate the influence of dentine location (peripheral vs. near pulp chamber) on resin tag formation.

Main Methods:

• Utilized human third molar teeth, decoronated and instrumented.
• Applied five DBAs and resin composite to the root face per manufacturer instructions.
• Examined resin tag length and density via scanning electron microscopy (SEM) after demineralization and deproteination.

Main Results:

• DBA-treated specimens showed minimal resin penetration in peripheral root-face dentine.
• Significantly longer and denser resin tags were observed in dentine overlying the pulp chamber.
• A potential hybrid layer was noted with DBA use, absent in controls; resin tags were sparser in controls.

Conclusions:

• Resin tag penetration (length and density) is superior in dentine adjacent to the pulp chamber compared to peripheral root-face dentine.
• The findings suggest differential sealing capabilities of DBAs based on root dentine location.
• Clinical implications regarding the sealing efficacy of DBAs in endodontic restorations are discussed.