Accelerated Reversal of Mid-face Paralysis Caused by Accidental Botulinum Toxin with Photobiomodulation: A Clinical Case Series
Letícia Veloso Moreira Frange
Master Program, School of Dentistry, Ingá University Center, Maringá, Paraná, Brazil.
Josué Júnior Araújo
School of Dentistry, São Judas Tadeu University, São Paulo, São Paulo, Brazil and Instituto Orofacial das Américas, Piracicaba, São Paulo, Brazil.
Jussara Marinho Dias Frasson
Instituto Orofacial das Américas, Piracicaba, São Paulo, Brazil.
Aline Coelho Quezadas
School of Dentistry, São Judas Tadeu University, São Paulo, São Paulo, Brazil.
Ingrid Grazielle Sousa
Instituto Orofacial das Américas, Piracicaba, São Paulo, Brazil.
Dimorvan Bordin
Master Program, School of Dentistry, Ingá University Center, Maringá, Paraná, Brazil and School of Dentistry, São Judas Tadeu University, São Paulo, São Paulo, Brazil.
Renato Assis Machado *
Master Program, School of Dentistry, Ingá University Center, Maringá, Paraná, Brazil, School of Dentistry, São Judas Tadeu University, São Paulo, São Paulo, Brazil, Instituto Orofacial das Américas, Piracicaba, São Paulo, Brazil and Graduate Program in Oral Biology, School of Dentistry, University of Campinas (FOP-UNICAMP), Piracicaba, São Paulo, Brazil.
*Author to whom correspondence should be addressed.
Abstract
Aims: This study reports two clinical cases in which iatrogenic complications were treated with photobiomodulation (low-level laser therapy).
Study Design: Clinical case series.
Place and Duration of Study: Instituto Orofacial das Américas, Piracicaba, São Paulo, Brazil, in August 2025.
Methodology: Two patients presenting with botulinum toxin-related complications were treated with photobiomodulation. In Case 1, mid-face paralysis caused by accidental infraorbital injection was managed with low-level laser therapy (4 J per point, nine application points) administered over 30 days. In Case 2, palpebral ptosis following corrugator injection was treated with a single laser session (4 J per point, two application points). Clinical outcomes were assessed using standardised serial photographs and functional evaluations of facial symmetry and muscle recovery.
Results: In Case 1, progressive recovery resulted in near-complete restoration of facial symmetry after 30 days. In Case 2, marked improvement in palpebral ptosis was observed within 24 hours of a single treatment session. These findings suggest that photobiomodulation may accelerate neuromuscular recovery and improve aesthetic and functional outcomes following botulinum toxin-related complications.
Conclusion: Photobiomodulation appears to be a safe and promising adjuvant therapy for managing iatrogenic complications associated with botulinum toxin type A. However, as these findings are based on two clinical cases, larger controlled studies are required to confirm its efficacy and establish standardised treatment protocols.
Keywords: Botulinum toxin type A, photobiomodulation, facial paralysis, ptosis