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Updated: Jun 22, 2026

Single-stage Dynamic Reanimation of the Smile in Irreversible Facial Paralysis by Free Functional Muscle Transfer
Published on: March 1, 2015
Mouth movement disturbance as a sequela of bilateral Bell's palsy
Masahiro Komori1, Naoaki Yanagihara, Keiko Kashiba
1Department of Otolaryngology, Takanoko Hospital, Matsuyama, Ehime, Japan. komori@m.ehime-u.ac.jp
Objective:
Bell's palsy rarely recurs or arises bilaterally. We describe unique oral motor sequelae that manifest with bilateral facial palsy.
Patients:
Two rare patients with alternating bilateral Bell's palsy experienced compromised mouth movement, affecting eating, speaking, and air exchange, and reduced quality of life.
Interventions:
Rehabilitation programs.
Main Outcome Measures:
Electromyography and electroneuronography.
Results:
On electromyography study, little activity of the orbicularis oris muscle was seen in any mouth or eye movement in Case 1. In Case 2, the electromyography activity of the depressor anguli oris and depressor labii inferioris muscles was stronger than that of the orbicularis oris muscle. The 2 cases demonstrated different patterns of recovery after the same subsequent treatment.
Conclusion:
Different patterns of reinnervation occur in bilateral Bell's palsy. Mouth movement disturbances after bilateral Bell's palsy are most disabling when incomplete reinnervation (as suggested by electroneuronography) of the orbicularis oris muscle occurs. Misdirection of regenerating nerve fibers produces lesser levels of oral motor impairment.
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