Facial muscle is different from skeletal muscle
Most muscles in the body extend between two bones and move the bones. Facial muscles are not like that. Many originate from bone but their other end attaches directly to the skin. When they contract, they move the skin, not the bone. This is why what we call facial expressions occur: the skin wrinkles, lines form.
The aesthetic result of the muscle model attached to the skin is this: every mimic line is a projection of the vector of the underlying muscle. Vertical lines usually result from muscles pulling horizontally, and horizontal lines from muscles pulling vertically. This logic is the essence of clinical reasoning that determines how much dose to give to which muscle.
Elevator and depressor duo
It is practically useful to divide facial muscles into two main groups: elevator muscles (lifting upwards) and depressor muscles (pulling downwards). The frontalis (forehead muscle) is an elevator — it lifts the eyebrows upwards. The orbicularis oculi and procerus are depressors — they pull the eyebrows and eyelid downwards. Suppressing an elevator muscle directs the face downwards; suppressing a depressor muscle "lifts" the face upwards.
In the clinic, most complaints of "my eyebrow dropped" are due to excessive suppression of the forehead muscle. The solution is not to lock the entire forehead; instead, target the glabellar (between eyebrows) and orbicularis depressors, while preserving the frontalis elevator force. This is precisely the "lifting" logic in Botox — silencing the depressor muscle to make way for the elevator.
Elevator muscles
- Frontalis — forehead, lifts eyebrows
- Levator palpebrae — upper eyelid
- Zygomaticus major — pulls corner of mouth up in a smile
- Levator anguli oris — lifts corner of lip
Depressor muscles
- Procerus — pulls down between eyebrows
- Corrugator — "frown" movement
- Orbicularis oculi — closes eyelid
- Depressor anguli oris (DAO) — pulls corner of mouth down
- Platysma — neck muscle, pulls jawline down
Three phases of mimic lines
Every mimic line is divided into three phases: dynamic, static, and structural. A dynamic line is visible only when making an expression; the skin is not yet damaged, only folded. A static line is permanent even at rest because repeated muscle contraction has disrupted the collagen network. A structural line, on the other hand, is due to changes in bone and fat compartments — Botox alone is not enough.
Botox works best in the dynamic phase. For lines that have progressed to the static phase, Botox will lighten the line but not completely erase it; here, supports such as skin boosters, microneedling, or peels are needed. In the structural phase, volume/architectural interventions such as fillers and threads come into play. So Botox is not a magic eraser; it is the right tool at the right stage.
Clinical note:In patient examination, I first work with the "make an expression, then rest" sequence. Botox is a good solution for lines that appear with expression and disappear at rest. If there are lines that remain at rest, a plan is not made without discussing fillers/skin treatments with the patient.
Why is it wrong to silence every mimic?
Facial expression is the balanced cooperation of muscles. Completely shutting down a mimic also silences the emotional feedback that feeds that expression. The human brain briefly mimics the other person's expression when empathizing; if this mimicry is not possible, communication weakens. In other words, a heavily suppressed face, even if it seems to "correct" the patient's appearance, expensively disrupts their social communication.
My clinical goal is never to "remove your mimic"; it is always to "reduce the production of your mimic, maintain balance." This principle will reappear in every region from section 6 onwards.
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