Clinical Application of Botulinum Toxin Type A in the Management of Masseter Muscle Hypertrophy: A Narrative Review

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Published: Apr 28, 2026
Keywords:
Masseter muscle hypertrophy Botulinum toxin type A Temporomandibular disorders Facial esthetics Injection techniques

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Atapol Yongvikul
Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Bangkokthonburi University., Department of Oral and Maxillofacial Surgery, Masterpiece Plastic Hospital, Bangkok.
Thongnard Kumchai
Deanery office, Faculty of Dentistry, Bangkokthonburi University.

Abstract

Objective: To explore the clinical application of botulinum toxin type A (BTXA) in the treatment of masseter muscle hypertrophy (MMH), with emphasis on its mechanism of action, administration techniques, therapeutic outcomes, and potential adverse effects.


Materials and Methods: A narrative review was conducted by searching databases including ThaiJo, PubMed, Scopus, and Web of Science using keywords such as “botulinum toxin” “masseter muscle hypertrophy” “mechanism of action” “side effects” and “treatment outcomes” Studies published in English or Thai were included, while case reports and studies lacking sufficient data were excluded.


Results: BTXA has been shown to effectively reduce masseter muscle volume, enhance facial aesthetics, and alleviate symptoms associated with temporomandibular disorders (TMD). Despite its temporary effects requiring repeated injections, BTXA remains a minimally invasive, well-tolerated treatment with a low complication rate.


Conclusion: BTXA is a safe and effective non-surgical option for managing MMH. Optimizing injection protocols and understanding the pharmacodynamics of BTXA are essential for achieving favorable therapeutic outcomes and minimizing adverse effects.

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Yongvikul A, Kumchai T. Clinical Application of Botulinum Toxin Type A in the Management of Masseter Muscle Hypertrophy: A Narrative Review. Khon Kaen Dent J [internet]. 2026 Apr. 28 [cited 2026 Apr. 29];29(1):1-19. available from: https://he01.tci-thaijo.org/index.php/KDJ/article/view/280588
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Vol. 29 No. 1 (2026): Jan-Apr (in press)
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