Dental bridges and (artificial) crowns are fixed dentures – in contrast to partial and total dentures which can be removed. A “crown” is the sheeting of a still existing but (extremely) damaged tooth while “bridge” describes a process where a lost tooth is completely replaced.
The decision whether to use crowns or bridges is determined by the answer to the question if only the (natural) dental crown or also the root has been damaged. The (natural) dental crown is the part of the tooth, that protrudes out of the gums, while the root anchors the tooth in the jaw and is generally not at all or only slightly visible. If only the natural dental crown is damaged, but the root is still in good order, the natural dental crown is whetted and the artificial crown is mounted. If the natural dental crown has already been reduced in an extent that the artificial crown would not find enough stability a so-called pivot crown is inserted. In this case the crown is anchored to the tooth root by a metallic pivot. However, this requires a previous – or already realized – root canal treatment.
But if also the root is damaged and has to be removed the gap is closed by a bridge. In this case, artificial crowns are placed on the teeth neighbouring the gap (the so-called pillar teeth) and the denture replacing the lost tooth is mounted as kind of an intermediate link, so that a complete row of teeth is achieved. As an alternative to bridges a single dental implant, an artificial replacement of the lost root, can be inserted. Then the artificial crown is placed upon the implant. Crowns and bridges are either made of ceramics or of a metal-ceramics-alloy.