Conservative caries removal has become an integral part of minimally invasive dentistry (MID). Polymer and Cera burs are two feasible MID methods. The aim of the study was to compare the efficiency of Polymer, Cera, and Tungsten carbide bur in dentin caries excavation of mandibular primary molars. 45 children in the age group of 6-8 years with dentin caries, not involving pulp in the second mandibular primary molars, were selected for the study. The three burs compared were polymer bur, Cera bur, and Tungsten Carbide bur. The excavation of carious lesion was performed with each burs using a slow-speed handpiece with 500-1000rpm. Caries removal efficiency was evaluated using the Visual-Tactile method and confirmed Dye detection method. The time taken to complete the caries removal was measured using a stopwatch. The patient's pain perception was assessed using the Wong-Baker Faces Pain Rating Scale. The intergroup comparisons based on time, dye, and Wong-Baker Faces Pain Rating Scale (WBFPRS) were arrived at using Mann-Whitney and Fisher Exact tests at P < 0.0001. A statistical significance between the three groups on the time taken for caries removal at P < 0.0001. No statistical significance was observed between the three groups for caries removal efficiency and pain perception using the dye and WBFPRS scores at P > 0.001. Cera burs had shown high caries removal efficiency, which had taken less time in the excavation, with reduced pain perception followed by Tungsten Carbide bur and the polymer bur in mandibular primary molars. © 2024 Elsevier B.V., All rights reserved.