Long-Term Influence of Endodontic Irrigants on In Vitro Dentin Biomimetic Remineralization

Area of Science:

• Biomaterials Science
• Endodontics
• Dental Mineralization

Background:

• Endodontic irrigants are vital for dentin biomimetic remineralization, preparing the collagen scaffold for calcium phosphate infiltration.
• Understanding irrigant effects on dentin's mineral and organic phases is crucial for optimizing regenerative endodontic protocols.

Purpose of the Study:

• To investigate the short-term effects of various endodontic irrigants on dentin physicochemical properties.
• To assess the long-term impact of these irrigants on dentin remineralization potential under simulated clinical conditions.
• To correlate molecular-level changes with the capacity for dentin biomineralization.

Main Methods:

• Root dentin discs were exposed to sodium hypochlorite (3%), EDTA (17%), citric acid (10%), chlorhexidine (2%), and an experimental citric acid/surfactant formulation.
• Samples were aged in Hank's Balanced Salt Solution (HBSS) at 37°C for three months.
• Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy was used to analyze collagen and apatite modifications, assessing mineralization and carbonate content.

Main Results:

• Chlorhexidine (CHX) and EDTA treatments resulted in the highest degree of dentin remineralization after aging.
• Sodium hypochlorite (NaClO) impeded remineralization due to significant collagen degradation.
• The experimental irrigant induced initial demineralization but facilitated substantial remineralization via citrate-collagen binding and surfactant action.

Conclusions:

• Irritant selection significantly impacts long-term dentin remineralization potential in regenerative endodontics.
• CHX and EDTA show promise for enhancing biomimetic remineralization, while NaClO is detrimental.
• The experimental irrigant demonstrates potential for promoting dentin biomineralization, warranting further investigation.