An in Vitro Evaluation of a Carbon Fiber-based Post and Core System

Statement Of Problem: A self-contained post and core system, Composipost, comprising an epoxy-based carbon fiber post, a composite core material, and a low viscosity Bis-GMA bonding resin, has recently been marketed for the restoration of pulpless teeth.

Purpose: This study compared the in vitro performance and the failure characteristics of the Composipost system against existing post and core combinations.

Material And Methods: Using extracted human teeth, three post and core test groups and one control group were then tested to failure with an obliquely applied compressive load at 130 degrees in a Hounsfield testing-machine with a crosshead speed of 5 cm/minute.

Results: The mean stress values at failure (MNm.2) with standard deviations for each group were as follows: Composipost system 8.89, SD 2.40; stainless steel post and composite core 14.18, SD 3.49; cast gold alloy post and gold alloy core 15.25, SD 4.07; and endodontically treated tooth only 24.84 SD 4.58.

Conclusion: The specimens restored with the Composipost system exhibited inferior strength properties in comparison to the other post and core systems tested (p < 0.01). Teeth without post and core foundations tested significantly stronger than the other comparison groups (p < 0.01).