Retrospective study of tapered, smooth post systems in place for 10 years or more

Post and core systems, refinements to tooth preparation and cementation

“…17 Unfortunately, Sorensen and Martinoff (1984) 16 could not comment on the type of coronal tooth preparation carried out, but in a ten-year study of 138 teeth with a tapered cast post and cores only a 6.5% failure rate was recorded, with only two root fractures. 18 The lower failure rate and fewer root fractures was attributed to the presence of an adequate ferrule and careful tooth preparation. 18 Attention has also been drawn to the fact that the higher failure rate 16 may be due to the fact that nearly half of the posts were shorter than recommended from the literature (Fig.…”

Crowns and extra-coronal restorations: Endodontic considerations: the pulp, the root-treated tooth and the crown

“…Tapered posts such as the PD system have a good record of clinical success. 36 Concerns have often been raised over the generation of wedging stresses by tapered (including customised cast) posts, and the tendency to promote root fracture. However, such forces are not active in the same way as those generated by self-tapping screw systems, and it may be that many cases of root fracture associated with tapered posts reflect the type of cases in which such posts are often used, ie the wide, thin-walled tapered canal.…”

Development of a new direct core build-up method using a hollow fiber-reinforced post

“…However, it has been reported that teeth restored using a cast metal post and core or a metal post occasionally have to be extracted due to fracture of the root canal 3,4) . In the 1990s, a construction method using a carbon fiber post in combination with a resin core having an elastic modulus similar to that of dentin was invented 5) .…”