Methods for testing solubility of hydraulic calcium silicate cements for root-end filling

Area of Science:

• Biomaterials Science
• Dental Materials
• Materials Testing

Background:

• Absence of regulatory testing standards for hydraulic cements in dentistry.
• Need for standardized methods to evaluate root-end filling materials.
• Existing methods may not accurately reflect clinical conditions.

Purpose of the Study:

• To develop a simple, reproducible solubility testing method for hydraulic root-end filling materials.
• To compare a novel method with existing ISO standards.
• To evaluate the influence of different testing media on solubility results.

Main Methods:

• Characterization of commercial and prototype hydraulic cements using SEM and XRD.
• Solubility testing via ISO 6876:2012, a modified ISO method with alternative media, and a new micro-CT based method.
• Intra-laboratory comparison involving three operators to assess reproducibility.

Main Results:

• Solubility data varied significantly based on the testing method employed.
• The standard ISO 6876 method detected significant differences in material solubility (p < 0.05).
• Modified ISO methods and the new micro-CT method showed less sensitivity to solubility differences and operator variability.

Conclusions:

• The choice of testing medium significantly impacts the solubility assessment of hydraulic cements.
• The proposed micro-CT method, while simple and mimicking clinical conditions, requires further refinement for robustness.
• Development of standardized, clinically relevant testing protocols for dental hydraulic materials is crucial.