AH Plus (Pack: $4 \text{ ml} + 4 \text{ ml}$) – A Two-Component Epoxy-Amine Resin Cement for the Permanent Obturation of Root Canals

Features high sealing ability, biocompatibility, and volume stability.

AH Plus (Dentsply) - Epoxy Resin-Based Root Canal Sealer

AH Plus is one of the most famous and most researched two-component sealers (paste/paste) for the permanent obturation of root canals, developed by Dentsply Sirona. It is based on an epoxy-amine resin system that provides unmatched sealing ability, stability, and biocompatibility.

Technology and Composition

AH Plus is a sealer that sets through a polyaddition reaction between two pastes:

• Paste A (Epoxy): Contains epoxy resins (Bisphenol-A and Bisphenol-F), which are the basis of the polymer network. It also includes radiopaque fillers (calcium tungstate, zirconium oxide) and pigments.

• Paste B (Amine/Catalyst): Contains various types of amines (e.g., dibenzyl diamine), which act as catalysts, initiating the polymerization reaction. It also includes radiopaque fillers.

Key Technological Features:

• Epoxy-Amine Matrix: This type of resin creates a highly stable and strong polymer network upon setting, which is key to long-term sealing.

• Minimal Shrinkage: Unlike many other sealers, AH Plus exhibits extremely low polymerization shrinkage (often less than $1\%$), which is critical for preventing the formation of micro-gaps between the sealer and the dentin walls.

• Self-Adhesive Properties: The sealer has the ability to self-adhere to the root canal dentin ($\approx 6.5 \text{ MPa}$), which improves adaptation and sealing.

Key Advantages

• Exceptional Sealing Ability: Due to minimal shrinkage and adhesion, AH Plus provides one of the best seals in endodontics, as confirmed by numerous studies.

• Outstanding Dimensional Stability (3D): The set material is chemically stable, does not dissolve in tissue fluids, and maintains its shape over a long period.

• High Radiopacity: Provides excellent visibility on radiographs (up to $13.6 \text{ mm/mm Al}$), allowing for accurate monitoring of obturation quality.

• Biocompatibility: The material is recognized as biologically inert after setting, demonstrating low cytotoxicity, which is important for periapical tissues.

• Optimal Working and Setting Time:

  • Working Time (at room temperature): At least 4 hours, allowing for comfortable work even in complex cases.

  • Setting Time (at $37^{\circ} \text{C}$): A minimum of 8 hours, which ensures ideal penetration into the dentinal tubules and lateral ramifications.

• Compatibility with Obturation Techniques: Suitable for use with both cold (points, lateral condensation) and warm gutta-percha (e.g., vertical condensation technique or the ThermaFil system).

Application

AH Plus is used for the permanent obturation of root canals in combination with a core material (most often gutta-percha points).

Due to its properties, it serves as the gold standard sealer in many clinical studies and is the No. 1 choice for many endodontists worldwide.