Permeability of apical barriers.

Area of Science:

• Endodontics
• Dental Materials Science
• Biomaterials

Background:

• Root canal therapy aims to seal the entire root canal system.
• Apical barriers are crucial for preventing coronal leakage and promoting periapical healing.
• Evaluating the hydraulic conductance of potential barrier materials is essential for clinical success.

Purpose of the Study:

• To measure and compare the in vitro permeability (hydraulic conductance) of different root canal apical barrier materials.
• To assess the efficacy of autogenous dentin chips, calcium hydroxide, and durapatite as apical barrier materials.
• To validate a novel technique for evaluating the sealing properties of endodontic barrier materials.

Main Methods:

• Standardized apical openings were created in 30 extracted teeth.
• One-millimeter thick barriers of autogenous dentin chips, calcium hydroxide powder, or durapatite particles were placed.
• Teeth were mounted in a chamber to measure fluid flow under applied pressure (20 psi).
• Permeability was calculated as microliters per second per psi.

Main Results:

• Autogenous dentin chip barriers exhibited a mean permeability of 0.0010 µL/s/psi.
• Calcium hydroxide barriers showed a mean permeability of 0.0012 µL/s/psi.
• Durapatite particle barriers were significantly more permeable, averaging 0.0220 µL/s/psi.
• Dentin chip and calcium hydroxide barriers demonstrated significantly lower permeability than durapatite (p = 0.05).

Conclusions:

• The developed technique is effective for evaluating the hydraulic conductance of apical barrier materials.
• Autogenous dentin chips and calcium hydroxide are superior to durapatite particles for creating low-permeability root canal apical barriers.
• These findings support the use of dentin chips and calcium hydroxide in endodontic procedures requiring apical sealing.