Delayed onset peripheral facial nerve palsy after dental extraction: a case report and literature review.

Peripheral facial nerve palsy (PFP) is a rare occurrence after dental extraction. Early onset PFP after the procedure can be caused by trauma and/or local anesthesia, whereas delayed onset PFP has more speculative etiologies. The latter has a certain affiliation to Bell's palsy and is therefore primarily treated with corticosteroids, and long-term follow-up is often warranted. This article reports a unique case of a 30-year-old woman developing a delayed onset right-sided PFP after local intraoral anesthetic injection for molar extraction. Facial nerve injury was identified with signs of denervation and neuritis and the patient was treated with nonsteroidal anti-inflammatory drug, corticosteroids, vitamin B supplements, and mime therapy. After 9 months, the patient showed an improvement of the facial muscle activity and went from a grade IV to a grade III on the House-Brackmann grading scale.