Lower Face and Neck Toxin Injection Techniques and Complications

Conclusions

• Botulinum toxin can be used effectively in the lower face and neck, but most of these applications are off-label and require careful patient selection and consent.
• Successful treatment depends on precise anatomy, matching dose to muscle mass, and injecting superficially into the correct muscle belly while avoiding unintended spread.
• Preserved saline, topical anesthesia, small-gauge needles, and careful post-injection measures can improve comfort and reduce bruising.
• Treating perioral muscles such as the orbicularis oris, DAO, mentalis, and depressor septi can improve aesthetic balance, but over-treatment can impair speech, eating, kissing, and lip competence.
• The levator labii superioris alaeque nasi and nasalis muscles can be useful targets for gummy smile, bunny lines, and nasolabial fold blunting, but they carry trade-offs such as lip ptosis or altered lip shape.
• Depressor anguli oris treatment can lift downturned mouth corners and soften a sad expression, but it must be done carefully to avoid the depressor labii inferioris and unwanted asymmetry.
• Mentalis toxin can reduce chin dimpling and mental crease appearance, though filler may be better for etched-in lines.
• Masseter reduction can slim a square jaw and help bruxism or TMJ symptoms, but too much toxin may interfere with chewing.
• Platysma toxin can improve neck bands and create a sharper cervicomental angle, while décolleté and trapezius treatments may offer additional aesthetic benefits in selected patients.
• The overall conclusion is that lower-face and neck toxin works best as part of combination therapy, with pre-treatment photographs, thorough counseling, and caution because complications in this region are often more functional and harder to manage.