OBJECTIVE: The present research aims to examine the effectiveness of 980 nm Diode Laser and Twin Kleen irrigant individually in addition to the combo for removing the smear layer from tooth canals in single-rooted teeth. MATERIALS AND METHODS: 60 single-rooted mandibular premolar teeth were chosen and inspected clinically and by radiography. Protaper was employed to prepare teeth up to F4. Irrigation with 5.25% sodium hypochlorite followed each consecutive instrument. The collected, prepared teeth were distributed at random to four distinct groups of fifteen teeth each: (a) Group I: Normal saline
(b) Group II: Twin Kleen
(c) Group III: Diode Laser
(d) Group IV: Diode Laser in combo with Twin Kleen. Scanning Electron Microscope evaluation was performed. The topography of the surfaces of the 4 groups was studied, and the results were photographed. Microscopy images captured under 1000x. Using the Guttman grading methodology, the smear layer scores have been determined in the cervical, mid and apical root areas. RESULTS: Smear layer removal scores in the cervical area were least in Group III and highest in Group I. Smear layer removal scores in the middle area were least in Group III and highest in Group I. Smear layer removal scores in the apical area were least in Group IV and highest in Group I. CONCLUSION: It is determined that the diode laser, in combination with Twin Kleen, improves smear layer elimination, particularly from the apical region. 980 nm diode laser can be employed as an irrigant activating technique that allows for improved absorption into restricted root canal locations.