Introduction: Root canal filling materials alter the flexural strength of dentine, leading to fracture under compressive loads. Therefore, root-filled teeth commonly undergo further tooth fracture. In this regard, Biodentine may offer an alternative to current conventional materials. Aims: This study aimed to evaluate the fracture resistance (compressive strength) of permanent teeth after filling the root canals with a calcium tri-silicate cement (Biodentine) and gutta-percha. Furthermore, the type of fracture in simulated permanent teeth when loaded to failure was recorded. Methodology: Twenty extracted mandibular first premolar teeth were randomised into two groups: Biodentine and gutta-percha. All teeth were prepared to size 70 K-file at the apex. In one group gutta-percha was placed as far as the cementoenamel junction; in the other, Biodentine was used to fill the canal to the CEJ. Both groups received composite as coronal restoration. To decide on the best method of determining the maximum compressive strength endured by each sample prior to fracture, a static loading test was used. An INSTRON machine was used to apply the force starting from zero Newtons to failure. This was used to measure whether the teeth fractured within the known range of the normal human bite-force. The test was applied to both groups. Results: There was no significant difference in the fracture resistance (compressive loading) between the Biodentine and gutta-percha groups. Crown fracture was the most common type of fracture in both groups. Conclusions: This study suggests that Biodentine should be further investigated in vitro in the treatment of non-vital teeth. Schlagwörter: Flexure strength, cementoenamel junction