Marionette lines run from the corners of the mouth downward toward the chin. They are caused by the depressor anguli oris (DAO) — a muscle that pulls the oral commissures downward — combined with progressive structural volume loss in the lower face. The result is a resting expression that appears sad, fatigued, or stern.
How Marionette Lines Form
The DAO is a triangular muscle originating from the mandible and inserting at the oral commissure. Its repeated downward pull, combined with the natural ptosis of lower facial soft tissue with age, produces deepening grooves and a downturned oral commissure — one of the most age-revealing features of the lower face.
Mild Downturn
Subtle downward pull at the oral commissure visible at rest. Highly responsive to DAO relaxation with minimal dosing.
Established Groove
A visible line extending from the commissure toward the chin. Treatment addresses the muscular component; structural support may be discussed.
Deep Fold
Significant volume loss and deep creasing. Combination approaches — neuromodulator plus structural augmentation — typically required for meaningful improvement.
Typical Dose
2–4 units per side; conservative dosing is essential given proximity to smile muscles
Duration
3–4 months; the high mobility of the lower face can shorten duration relative to upper face treatments
Commissure Lift
By reducing downward pull, the oral commissures adopt a more neutral — or subtly elevated — resting position
Treatment Approach
Botulinum toxin is injected into the DAO at the corners of the mouth. By reducing its downward pull, the corners of the mouth are allowed to sit in a more neutral position. A staged, conservative approach is always preferred — the DAO sits in close proximity to the muscles responsible for smiling and lip movement.
"Addressing marionette lines can restore a sense of restfulness and approachability to the lower face — without altering its fundamental character."
The DAO sits in close anatomical proximity to the zygomaticus major, depressor labii inferioris, and mentalis. Overly aggressive treatment or imprecise placement can cause asymmetric smiling, lip ptosis, or mental crease deepening. Conservative dosing and precise localisation are non-negotiable.
For patients with marionette lines driven primarily by volume loss rather than muscle activity, neuromodulator treatment alone may produce limited improvement.
A combination approach incorporating structural support can be discussed — the neuromodulator addresses dynamic downward pull, while structural support addresses the volumetric component of the fold.
Injection Depth — Critical Technique
Inject into the body of the DAO — intramuscular at moderate depth, angling slightly inferiorly. Avoid superficial injection (poor efficacy) and avoid deep injection near the mandibular periosteum, which risks the marginal mandibular branch of the facial nerve and can cause prolonged lip and chin weakness.
Aftercare Instructions
Remain upright for four hours following treatment.
Move your mouth normally — talk, smile and eat as usual to assist absorption.
Book a two-week review to assess symmetry and commissure position.
Play wind instruments or perform sustained lip movements for 4 hours post-treatment.
Apply pressure or massage around the mouth or chin area.
Exercise strenuously or expose the area to excessive heat for 12 hours.