A Novel 3-Point Injection Technique for OnabotulinumtoxinA in the Upper Depressor Anguli Oris

Area of Science:

• Aesthetic medicine
• Neuromodulators
• Facial anatomy

Background:

• Downturned mouth, often caused by depressor anguli oris (DAO) hyperactivity, presents an aesthetic challenge.
• OnabotulinumtoxinA (ONA) is a widely used neuromodulator for cosmetic applications.
• Targeting the DAO muscle with ONA offers a potential solution for correcting oral commissure asymmetry.

Purpose of the Study:

• To evaluate the efficacy and safety of onabotulinumtoxinA (ONA) injections into the DAO muscle.
• To assess the improvement in downturned mouth appearance using a novel 3-point injection technique.
• To determine the duration of aesthetic improvement and patient satisfaction.

Main Methods:

• Prospective, placebo-controlled study involving 20 subjects (18-65 years).
• Administration of ONA or placebo via a novel 3-point technique in the upper DAO (1.5 U/injection site).
• Primary endpoint: 1-grade improvement on a DAO contraction scale; secondary endpoint: Global Aesthetic Improvement Scale (GAIS).

Main Results:

• Significant improvement in DAO scores observed in ONA-treated subjects at Weeks 4 and 12 (p < .001) compared to baseline.
• 100% of ONA subjects showed improvement at Week 4, and 90% at Week 12, per GAIS.
• Treatment was well-tolerated, with no significant difference in placebo subjects and sustained improvement in most ONA recipients.

Conclusions:

• OnabotulinumtoxinA injections to the DAO using a 3-point technique yield clinically meaningful improvements in facial aesthetics.
• The treatment is safe and well-tolerated, offering a durable solution for downturned mouth.
• Patient-reported outcomes align with clinical assessments, confirming the effectiveness of ONA for DAO.