Pre-Emptive Analgesia with Ketamine for Relief of Postoperative Pain After Surgical Removal of Impacted Mandibular Third Molars

Purpose: In this study we assessed the clinical efficacy of sub-mucosal injection of ketamine at sub-anesthetic dose of 0.5 mg/kg on post-operative pain, swelling and trismus following surgical extraction of impacted mandibular third molars. Methods: Forty bilaterally symmetrical impacted mandibular third molars in 20 patients who required surgical removal were included in the study. Within the same individual, one of the sites received a test medication whereas the other site was used as control. All patients received nerve blocks with local anesthetic (2 % lignocaine hydrochloride with 1:80,000 adrenaline); the Test group received sub-mucosal infiltration of 0.5 mg/kg of ketamine hydrochloride (without preservative) around the impacted mandibular third molar and along the incision line, while the Placebo group received normal saline infiltration, 10 min before placement of the incision. Results: The pain scores on VAS at 30 min, 1, 4, 12 h and 1 day post-operatively was significantly lower in the Test group than in the Placebo group (p < .05). With respect to facial swelling and mouth opening the Test group and Placebo group showed overall no statistically significant difference (p > .05) on the 1st, 3rd and 7th post-operative days. Conclusion: The sub-mucosal injection of 0.5 mg/kg ketamine administered before surgical removal of impacted mandibular third molars was found to be effective in significantly reducing post-operative pain for the first 24 h. © 2015, The Association of Oral and Maxillofacial Surgeons of India.