The present study aimed to compare the number of un occluded dentinal tubules and the diameter of un-occluded dentinal tubules with 940 nm diode laser with, or without graphite and desensitizing agent. Materials and methods: This in-vitro study consisted of three groups. Cross sectional slice of single rooted teeth (premolar) extracted for orthodontic purpose was used for the study. Group 1 (n=5) teeth coated with graphite and irradiated with 940 nm diode laser. Group 2 (n=5) teeth irradiated with 940 nm diode laser. Group 3 (n=5) teeth treated with desensitizing agent. Then SEM analysis using 2500 X magnification was done to analyse number of un occluded dentinal tubules and diameter of remaining dentinal tubules .Statistical analysis was done using Mann- Whitney test and Kruskal-Wallis test. Results: Results concluded that there was no statistical difference between the three groups - diode laser with graphite group, diode laser and desensitizing agent in the remaining number of un occluded dentinal tubule occlusion. Diode laser with Graphite group (1.40±1.949) showed reduced number of un occluded dentinal tubules. There was statistical difference between three groups in diameter of remaining open dentinal tubules after the usage of Diode laser with graphite (0.2760±0.39068) compared to diode laser group and desensitizing agent group.