Polyether (PE) impression material is an elastomeric substance used by dental professionals to create precise molds of teeth and surrounding oral structures. This material is essential for creating custom-fitted restorations, such as crowns, bridges, and implant components. Polyether’s chemical structure provides distinct advantages, making it a preferred choice for intricate restorative procedures. These qualities ensure the production of accurate molds, leading to better-fitting final dental restorations.
Performance in Moist Environments
A defining characteristic of polyether impression material is its compatibility with moisture, known as hydrophilicity. Unlike materials that repel water, polyether naturally interacts with liquids in the mouth, including saliva and blood, through a low wetting angle. This property allows the material to flow into moist areas and wet the tooth surface effectively, minimizing the chance of trapping air bubbles that compromise accuracy.
This moisture tolerance is beneficial when capturing details around the gum line (subgingival margins), where maintaining absolute dryness is nearly impossible. The material’s ability to remain stable and flow accurately despite this moisture ensures the impression captures the complete shape of the prepared tooth.
Accuracy and Fine Detail Reproduction
Polyether is engineered with excellent flow properties, meaning it has low viscosity when dispensed. This allows it to move into the smallest crevices of the tooth preparation. This fluidity, combined with its ability to wet the tooth structure, permits the material to capture minute anatomical details, such as the precise finish line of a crown preparation. The superior flow ensures the final mold is a high-resolution replica of the oral structures.
Once the polyether sets, it gains significant rigidity, or stiffness, which contributes to its accuracy. This rigidity helps the impression resist deformation when removed from the mouth, especially when pulling away from undercuts or tight spaces between teeth. The material’s strength prevents fine details, like preparation margins, from tearing or distorting during removal, preserving the integrity of the captured mold.
Long-Term Reliability and Stability
Polyether demonstrates excellent dimensional stability, meaning the mold maintains its size and shape over time. This is a practical advantage for dental laboratories, as the impression does not need to be poured immediately with gypsum to create the final model. Polyether impressions can typically be stored for an extended period, often for one to two weeks, without significant changes in dimension.
This stability allows for reliable transport to a remote dental lab and provides flexibility in scheduling the pouring of the model. Even with minor polymerization shrinkage after setting, the overall dimensional change is very small, which is well within acceptable limits for producing an accurate restoration. This reliability helps reduce the risk of distortion and ensures the final restoration fits accurately.