Aim
The aim of this study was to evaluate the diode laser effect on root canal disinfection, fracture resistance, root canal cleanliness, and the bond strength of resin sealer to root canal dentin.

Materials and Methods
A total of 160 single rooted teeth were selected for this study, Samples were divided into 2 groups (n=80), Group A samples were finally irrigated using 980 nm diode laser. Group B samples were finally irrigated using NaOCl/EDTA. Samples from each group were evaluated for canal disinfection using the colony forming unit count, and Polymerase chain reaction. Samples were placed under scanning electron microscopic to evaluate the smear layer removal. A universal testing machine was used to measure the fracture resistance of teeth. Samples evaluated for the push-out test bond strength were obturated with resin based sealer, and mounted on a universal testing machine was used.
Results
The diode laser group showed higher bacterial reduction and better removal of smear layer than NaOCl/EDTA group. The diode laser group presented higher fracture resistance than NaOCl/EDTA group. The diode laser group showed better value of push out bond strength than NaOCl/EDTA group.
Conclusion
Diode laser is an efficient tool in bacterial reduction and removal of smear layer when used during final irrigation procedure, compared to NaOCl/EDTA.