Aims and objective: To evaluate the effect of various reinforcement techniques with polyethylene fibre and fibre post on the fracture resistance of endodontically treated teeth. Materials and methods: Forty intact maxillary premolars receiving endodontic treatment and MOD cavity preparation were divided into four groups: Group I - restored with resin composite; Group II - fibre post inserted into the palatal canal followed by resin composite restoration; Group III - polyethylene fibre inserted in the occlusal third of the MOD cavity followed by resin composite restoration; and Group IV - fibre post transfixed horizontally in a buccolingual direction within the MOD cavity, followed by resin composite restoration. Fracture resistance was evaluated using the Universal testing machine. Results: ANOVA statistical analysis showed no significant difference in the fracture resistance between Group 1 and Group 2, whereas, a significant difference was seen between Group 1 and Group 3 and also Group 1 and Group 4. The difference in mean fracture resistance was found to be statistically significant between Group 2 and Group 3 as well as between Group 2 and Group 4. No statistically significant difference was observed between Group 3 and Group 4 with respect to the mean fracture resistance (P > 0.05). Conclusion: Horizontally transfixed fibre post and polythelene fibre placed within the resin composite restoration showed improved fracture resistance. Parole chiave: fibre post, fracture resistance, polyethylene fibre