[Are Ag-points, gutta percha and amalgam still useful as apical filling materials?]

Nowadays Ag-points, gutta percha and amalgam are widely used as orthograde or retrograde root canal filling materials. The biocompatibility of these materials however remains debatable. Ag-points are easy to manipulate and when used together with an appropriate cement, offer an adequate seal. Yet an important disadvantage is the susceptibility to corrosion resulting in argyrosis and inflammatory reaction. Tissue cultures proved these corrosion by products to be highly cytotoxic. Other investigations, reported that the inflammatory tissue response seen with gutta percha, may be due to small amounts of additives included in gutta percha. Equally, there is no unanimity concerning the biocompatibility of amalgam, and the extent of corrosion and inflammatory reaction is possibly related to the composition of the amalgam used. Nevertheless in vivo studies demonstrated that, when freshly mixed amalgam, gutta percha or Ag-points are implanted in the femur of rats, mature bone was formed in direct contact with these materials.