Introduction Ropivacaine belongs to pipecoloxylidide group of local anesthetics. There are reports supporting the use of ropivacaine as a long acting local anesthetic in oral and maxillofacial surgical procedures, with variable data on the concentration that is clinically suitable. Materials and Methods A prospective randomized double-blind study protocol was undertaken to assess the efficacy of 0.5 and 0.75 % ropivacaine for inferior alveolar nerve block in surgical extraction of impacted mandibular third molars. A total of 60 procedures were performed, of which thirty patients received 0.5 % and thirty received 0.75 % concentration of the study drug. Results All the patients in both the study groups reported subjective numbness of lip and tongue. The time of onset was longer for 0.5 % ropivacaine when compared to 0.75 % solution. 90 % of the study patients in 0.5 % ropivacaine group reported pain corresponding to VAS >= 3 during bone guttering and 93.3 % patients reported pain corresponding to VAS > 4 during tooth elevation. None of the patients in 0.75 % ropivacaine group reported VAS > 3 at any stage of the surgical procedure. The duration of soft tissue anesthesia recorded with 0.75 % ropivacaine was average 287.57 +/- 42.0 min. Conclusion 0.75 % ropivacaine was found suitable for inferior alveolar nerve blocks in surgical extraction of impacted mandibular third molars.