Introduction
A root-filled tooth has often lost much of its crown to caries, old fillings and the access cavity. Too little is left to hold a crown, and the tooth is more likely to fracture. A post and core rebuilds the missing crown from inside the root, ready for a separate crown on top.
Before you start
The root filling must be sound:
- Good apical seal on the radiograph.
- No pain to pressure or at the apex; no exudate, fistula or active inflammation.
A poor root filling is redone first. The two deciding factors are the type of tooth and, most important of all, how much coronal tooth is left.
Parts
- Post (dowel): sits in the prepared root canal and gives retention.
- Core: rebuilds the lost crown and is prepared like a normal tooth to receive the crown.
One-piece post-crowns are now only of historical interest. Today the post and core is made first, and a separate complete crown is placed over it.