Ionomers are partially crosslinked ionomeric resins, and perform in peelable seal applications through delamination of the seal/seal interface.
Ionomers are polymers that contain a small number of ionic salt groups attached to hydrophobic organic backbone chains.
Seppa, "Studies on the effect of fluoride release by glass
ionomers in the oral cavity," Advances in Dental Research, vol.
Mount, "Glass
ionomers: a review of their current status," Operative dentistry, vol.
Early and long-term wear of conventional and resin-modifed glass
ionomers. J Dent Res, 1996; 75:1613-1619.
In fact, polymers containing ionic functionality in 15 mol% or less of the polymer repeat units have been defined as a unique class of polymers called
ionomers. (8) The unique properties of
ionomers which result from the aggregation of ionic groups into nanometer scale domains, typically referred to as multiplets, has resulted in the application of these materials in areas such as engineering thermoplastics, thermoplastic elastomers, packaging materials, and adhesives.
Ionomers, used in making the encapsulatnt sheets, are thermoplastic polymers.
* Total Petrochemicals in Houston has invented what it calls a "breakthrough resin technology," believed to be the first commercial styrenic
ionomer. Previous commercial thermoplastic
ionomers have all been based on ethylene, though styrene-based
ionomers are known in academic literature.
Sealants are generally either resin-based or glass
ionomers. Resin-based sealants, with their characteristics of flow ability and retentiveness, work exceptionally well and serve their function for many years when placed properly.
Glass
ionomers were introduced to the profession 25 years ago and have been shown to be a very useful adjunct to restorative dentistry.