Buccinator muscle: A new target for botulinum toxin injections in the treatment of facial paralysis sequelae

Facial paralysis can cause aesthetic and functional sequelae such as spasms and synkinesis. Botulinum toxin injection is one of the key treatments for these sequelae. Its use is widely reported in the literature for many muscles of the face but little for the buccinator muscle. However, its hyperactivity can be disabling, generating chewing and smile disorders in particular. The aim of this prospective study is to report the effects of botulinum toxin using a questionnaire specifically for the buccinator muscle. The study was conducted on 13 patients. The facial paralysis was of various origins. The questionnaire consisted of 10 questions each assessing a facial mimic involving the buccinator muscle. The rating scale ranged from -10 (major deterioration) to 10 (major improvement) for each question. The evaluation was done at 1 and 4 months after the injection. We found an improvement for all the mimics and gestures evaluated (0 to 7.38 at 1 month and 0.15 to 6.62 at 4 months). This improvement was greater at 1 month than at 4 months. Few side effects were reported. Botulinum toxin injections are an effective, safe therapeutic solution for the treatment of the facial paralysis sequelae of the buccinator muscle through a new specific questionnaire. Subsequently, it would be interesting to carry out an evaluation on a larger population and to compare it with other recognized scores in facial paralysis.