No conclusive evidence favouring cast over direct post and core preparations

Abstract

Data sources English, French or German articles were identified in Medline and EMbase, and in the reference lists of retrieved articles. Study selection The in-vitro studies were of single rooted teeth (no resin analogues) and load angles of 130–135°. In-vivo studies were of ⩾3 years’ duration. These included teeth that could be identified separately with complete crown restoration including fixed partial denture abutments and detectable information regarding success or failure. Data extraction and synthesis For in-vitro studies, primary outcome was load-to-failure. For in-vivo studies, failure was defined as a need for recementing, a new restoration of any kind, or tooth extraction. A qualitative synthesis of all included in-vitro and in-vivo studies was performed along with a meta-analysis of four in-vitro studies. Results Ten in-vitro and six in-vivo studies were included. The meta-analysis of four in-vitro studies revealed no significant difference in fracture load. There was also little difference in the mode of fracture across the 10 in-vitro studies. For three of the in-vivo studies it was possible to construct a life table that indicated the survival rate for cast posts was between 87 and 88% and for direct posts was 86% at 72 months. Conclusions There is no conclusive evidence favouring cast over direct post and core preparations or vice versa. The literature on the clinical success of post-retained cores is scare and randomised controlled trials are needed.