Botulinum toxin A, more commonly known as Botox, isn’t just a cosmetic quick-fix in beauty-conscious adults. A new study finds it can be utilized in younger patients who have suffered facial paralysis, to help restore some symmetry to their smiles.

Published in JAMA Facial Plastic Surgery, the study builds on prior success with restoring the smiles of adults who have suffered facial paralysis. As treatment stands now, patients with severe malformations must undergo reconstructive surgery or, in milder cases, a process known as muscle transfer that is similar to a graft completed with skin, to reconstruct the damaged portions of their face. The new method offers a viable third option, the researchers claim, which has been shown safe and effective.

“This study represents the largest pediatric population, to our knowledge, treated with botulinum toxin A,” wrote the study authors, who are based out of multiple universities in the U.S. and Europe.

They looked at 18 patients in total, between 4 and 17 years old, as they received treatment for a period of nine years. Treatment needs varied slightly between patients. Some had only asymmetrical smiles due to one size of their face being paralyzed, while some had larger portions of their face damaged by paralysis and others struggled with a misfiring of their facial nerves, a condition called synkinesis, in which the muscles essentially get confused and contract involuntarily.

Prior research has found several causes may underlie facial paralysis, either in conjunction or separately. One literature review published in 2005 found middle ear infections (acute otitis media) to be the most common source of facial paralysis, followed by blunt-force trauma and bone fracture; iatrogenic causes, meaning those incurred as a result of some other treatment; congenital; Bell’s palsy; and relapsing from a prior treatment.

In the latest study, trauma and resultant paralysis from tumor resection were the most common causes. Following routine injections in the various muscles surrounding their cheeks, eyes, mouth, and neck, the subjects were evaluated with facial analysis software that could highlight improvements in facial symmetry. “We used the software to measure the difference in vertical aperture between the paralyzed and nonparalyzed sides of the lip,” explained the authors. “For each patient, outcomes were determined by the change in lip deviation before and after botulinum toxin A injection.”

Results showed the average subject enjoyed a 61 percent improvement in their facial symmetry, from 3.5 millimeters to 1.5mm. They also showed no complications resulting from the treatment up to two years after their last injection, the authors noted, adding that subsequent studies should still seek to ensure the long-term effectiveness of the treatment.

“As such and knowing the potential for plasticity,” they stated, “the introduction of this treatment in the pediatric population can prove to be more beneficial.”

Source: Haykal S, Arad E, Bagher S, et al. The Role of Botulinum Toxin A in the Establishment of Symmetry in Pediatric Paralysis of the Lower Lip. JAMA Facial Plastic Surgery. 2015.