Mentolabial fold: what it is and how to assess it

The mentolabial fold is the horizontal crease that separates the lower lip from the chin. It is part of the normal contour of the lower third and helps define where the lip ends and the chin begins. What draws attention in the assessment is when it is very deep, very shallow or out of proportion with the rest of the profile.

Why does the mentolabial fold deepen?

The causes usually add up. The position of the chin weighs a lot: a retruded or poorly projected chin tends to accentuate the crease, because the lower lip sits ahead of the bony base. Hyperactivity of the mentalis muscle, which lifts and projects the chin, also marks the area, sometimes together with an "orange peel" look in the skin.

With age, volume loss and bone resorption of the jaw can make the fold more visible. Dental and occlusal factors also influence the position of the lower lip, which is why the region should be assessed together with the smile and the bite.

How does it enter the assessment?

The mentolabial fold is assessed mostly in profile. Its depth is read together with chin projection, lip volume and the overall facial profile. Treating only the crease, without looking at the position of the chin, may not solve the concern.

Depending on the case, the professional may consider restoring chin projection or toxin in the mentalis muscle, along with referral when the cause is skeletal or occlusal. Indication, product and volume are decisions for the qualified professional, after assessment. When hyaluronic acid is used, hyaluronidase must be on hand.

In Harmy

The Chin point appears in Harmy's marking. Projecting the chin with different volumes helps show the patient how a change in the chin alters the reading of the fold and the profile.

Also called: labiomental fold, mentolabial groove.