Intraoral Botulinum Toxin Injection in Mental Foramen Site in the Treatment of Trigeminal Neuralgia

BACKGROUND Botulinum toxin type-A (BTX-A), has been used successfully in trigeminal neuralgia treatment. In this research, a novel method is proposed to assess the effectiveness of the BTX-A injection to the mental nerve. The present study aimed to evaluate BTX-A injection effectiveness in the mental nerve of trigeminal neuralgia (TN) patients who had a trigger zone in the mental nerve distribution. METHODS In this quasi-experimental, pre-and post-test design without control group research, 50 units of BTX-A was injected into the mental foramen site in 20 patients. Pain frequency and Visual Analog Scale (VAS) was evaluated prior to the treatment and in the first week, the second month, the sixth month, and the first year after treatment. Responders were those patients with a decrease of 50 percent in the score of mean pain in the second and sixth month. RESULTS The study included 20 patients. Pain intensity and attack frequency was decreased significantly by BTX-A. Ninety-five percent of patients reacted to therapy in the first year. After an average period of 165 +/- 31.6 (44 - 235) days, 50 percent of patients encountered recurrence and, for a second time, received treatment. CONCLUSIONS Injection appears to be a very successful technique in the mental foramen site; the attack frequency and pain severity are reduced after each injection. Based on the present research, intraoral injection of BTX-A to the mental foramen site is an efficient and safe treatment. In TN and possibly other similar disorders, BTX-A can be a beneficial treatment technique. A fast and long-term advantage is provided by BTX-A, without systemic effects.