Fracture Resistance and Stress Distribution of Weakened Bovine Roots Restored with Different Glass Fiber Post Systems

Background/Objectives: The restoration of structurally weakened roots remains a clinical challenge. This in vitro study evaluated the fracture resistance, failure pattern, and stress distribution of weakened bovine roots restored with two glass fiber post systems under different remaining root dentin thicknesses.

Methods

Sixty bovine incisor roots were divided into six groups (n = 10): G1, 2 mm of remaining root dentin without a post; G2, 3 mm without a post; G3, 2 mm with an Exacto post; G4, 3 mm with an Exacto post; G5, 2 mm with a Splendor-SAP post; and G6, 3 mm with a Splendor-SAP post. Specimens underwent root canal treatment and standardized restoration, followed by 1,200,000 mechanical cycles at 88 N and 3.8 Hz and fracture testing at 45°. Finite element models were subjected to an 88 N oblique load. Fracture resistance was analyzed using Welch's one-way ANOVA followed by Games-Howell post hoc comparisons, whereas failure patterns were analyzed using the Fisher-Freeman-Halton exact test.