Traditionally, amalgam has been used for Class II restorations in primary teeth, but the use of amalgam has decreased in Scandinavia during the latest few decades, and now, amalgam has been banned in Norway and Sweden. Glass ionomer (GIC) adheres to tooth substance and has been a popular alternative to amalgam, but the traditional GIC products do not give as high longevity as amalgam in Class II restorations. As the traditional GIC has been improved (high viscous GIC), and GIC has been combined with resins (resin-modified GIC and polyacrylic acid modified composite resin), the longevity of restorations has improved. GIC containing materials are technique sensitive. The placing of materials containing resin should be done in steps when the thickness of the restoration exceeds 2 mm. Composite can be used as the top layer (“sandwich”). Uncured resin which may penetrate into the pulp and into the oral environment represents a potential risk for adverse effects although no scientific evidence exists so far. GIC contains fluoride which is released from the restoration. The clinical importance of this release has been disputed, but it is likely that this fluoride may have some caries preventive effect (secondary caries). Stainless steel crowns are recommended for restoring extensive carious lesions in primary molars.

Glassionomer – et velegnet fyllingsmateriale for primære tenner?
Espelid I, Dahl JE.
Aktuel Nordisk Odontologi 2014; Munksgaard Forlag 2014; 69-83