Intraoral Administration of Botulinum Toxin for Continuous Dentoalveolar Neuropathic Pain: A Case Series

Aims: To examine the analgesic effect, safety, and tolerability of intraoral administration of onabotulinum toxin A (BoNT/A) in patients suffering from intractable continuous dentoalveolar neuropathic pain. Methods: Eight patients (six women and two men) of ages ranging from 21 to 73 years (mean [standard deviation] 52.4 [16.1] years) suffering from continuous dentoalveolar pain for a mean duration of 5.8 (4.4) years received a submucosal injection of 10 to 25 units of BoNT/A into the vestibular mucosa surrounding the painful site. Pain intensity levels were recorded using a verbal rating scale (VRS). Safety and tolerability of BoNT/A were measured based on patient self-report, including any adverse effects reported by the patient at the injection site. Results: Five of eight patients reported positive pain reduction. In this group, mean pain intensity on a 0-10 VAS was 4.8 (2.2) at baseline and 2.6 (2.1) at postinjection. The analgesic effect was maximal between 7 and 14 days postinjection and lasted for 1 to 8 weeks before subsequently returning to the pre-injection levels. No adverse effects were reported at the injection sites. One patient noted transient partial hemifacial paralysis. Conclusion: These results suggest the potential therapeutic benefit of BoNT/A in the management of continuous dentoalveolar neuropathic pain. Further investigations conducted via well-controlled studies in the area of orofacial pain are warranted. Keywords: chronic pain, continuous neuropathic pain, dentoalveolar neuropathic pain, onabotulinum toxin A, orofacial pain