Introduction: The use of temporary restorations in the treatment of patients who need dental prostheses is considered as one of the necessary steps. Flexural strength is important as a key indicator in the selection of materials for temporary restorations, especially in the anterior and long areas. The present study was conducted with the aim of investigating the bending strength of temporary restorations made with milling and 3D printing in comparison with the conventional method.
Methods: The main model of the temporary restoration was designed and produced using milling and 3D printing techniques. Three-unit restoration samples were subjected to post-processing processes after fabrication and preserved in artificial saliva. Then, the samples were subjected to thermocycling and the three-point bending test was performed on them. The results showed that the highest average bending strength was related to the samples printed with an angle of 45 degrees, and statistically, they showed a significant difference compared to other groups. On the other hand, the restorations produced by the traditional method had the lowest bending strength. Data were analyzed using SPSS24 statistical software and ANOVA and LSD tests.
Results: A significant difference was observed between different groups, so that the 3D printer method with an angle of 45 degrees has significantly higher bending strength than other methods (P<0.05). 
Conclusion: These findings show the effect of different manufacturing methods on the mechanical properties of restorations and emphasize the use of advanced technologies such as 3D printing in dentistry. The use of these technologies can help improve the performance and durability of temporary restorations and improve the quality of dental treatment.