Evaluating Outcomes of Selective Myectomy of Depressor Anguli Oris, Buccinator, and Platysma in Facial Synkinesis

Abstract

Introduction

Selective myectomy has gained popularity for treating facial synkinesis.

Objectives and Hypotheses

We examined the combined effectiveness of depressor anguli oris (DAO), partial buccinator, and platysma myectomies.

Study Design

Retrospective case series.

Methods

Pre- and postoperative botulinum toxin-A (BTX-A) treatments of selective myectomy patients were collected. Facial photographs were analyzed using Emotrics + . Facial Asymmetry Index (FAI) and electronic facial paralysis assessment (eFACE) scores were calculated.

Results

Twenty patients underwent myectomies. Improvements (mean ± standard error) were seen in several smile metrics, including FAI by 2.80 ± 0.68 mm, nasolabial fold angle by 4.78 ± 1.83 degrees, and smile angle by 4.43 ± 1.18 degrees (all p < 0.05). Postoperative FAI was 2.79 mm. Total BTX-A decreased by 10.85 ± 4.48 units (p = 0.03). eFACE revealed improved oral commissure movement and platysmal synkinesis (p < 0.05 for both).

Conclusion

Combined myectomies of the DAO, partial buccinator, and platysma clinically and statistically improve smile in facial synkinesis.

Keywords

selective myectomy - facial synkinesis - platysmectomy - facial asymmetry - botulinum toxin

Publikationsverlauf

Eingereicht: 14. September 2025

Angenommen nach Revision: 05. November 2025

Accepted Manuscript online:
07. November 2025

Artikel online veröffentlicht:
25. November 2025

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