the fracture resistance of anterior endodontically treated teeth prepared with a 2-mm ferrule, restored with glass fiber and zircon posts and composite resin cores or cast posts and cores.
Twelve matched pairs of teeth were obtained from 4 cadavers, and all were endodontically treated and prepared with a standardized 2-mm ferrule. According to a random number table, the 2 teeth from each matched pair were randomly divided into 2 groups. The test group consisted of 12 specimens restored with a glass fiber and zircon post (Fibio) and composite resin (Durafil) core. Twelve matching specimens restored with a nickel-chromium (NiCr) cast post and core served as the control. Specimens in both groups were cemented with resin cement (Panavia F). After cementation of cast NiCr complete crowns with zinc polycarboxylate cement (ShangChi), the specimens were loaded with an incremental static force at an angle of 135 degrees to the long axis of the root until failure occurred. A paired sample t test was used to compare the fracture resistance (N) of teeth restored with the 2 post-and-core systems (α=.05).
the teeth restored with glass fiber and zircon posts demonstrated significantly lower failure loads than those with cast NiCr post and cores. All specimens failed via root fractures.
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