Effect of Ferrule Placement on the Fracture Strength of Cyclically Loaded Bovine Teeth Restored with Cemented Cast Post-Cores and Crowns

This experiment investigated the effect of a ferrule on the strength and fracture resistance of bovine teeth restored with cemented cast post-cores and crowns, compared to crowns alone or to crowns over non-ferrule cores. Thirty restored bovine teeth were subjected to 4 x 10(5) cycles from 20 N to 120 N at 10 Hz, followed by fracture testing. Crowns alone were weaker than post restored teeth. There was no difference in fracture strength between ferrule and non ferrule teeth restored with crowns. All of the fractured teeth were subsequently unrestorable. Conclusions: Fracture resistance was not enhanced by 2 mm ferrule height.