Jawline and chin filler: what hyaluronic acid can and cannot do

Why the jawline fades

As elsewhere on the face, several layers change at the same time:

• Bone. With age, the lower jaw loses height and length, and its angle opens. These changes contribute to the aged appearance of the lower face.
• Fat. The fat along the jaw shrinks, and a fibrous partition that held it along the bone gives way. Jowls appear.
• Skin. It loosens, the tissues descend along the jaw, and the chin may look less projected.

Angle, jaw, chin: one contour

People now readily talk about the "jawline". In practice, the contour is treated at several points: the angle of the jaw below the ear, the edge of the bone, the small hollow that forms in front of the jowls, and the chin. We only treat what is missing, based on the measurements of your face.

The aim is not to draw a jaw that is not yours. A wide jaw caused by a very developed masseter muscle is a different situation altogether: adding gel would widen it further.

Jawline filler: firmer gels, placed deeper

To redefine a contour, two properties of the gel matter most. Its elasticity, meaning its firmness and its ability to regain its shape when pressed. And its cohesivity, meaning its tendency to stay in one piece rather than spread. For the facial contour, we generally choose firm, highly elastic gels, different from those used for the lips or under the eyes.

At the chin and the angle of the jaw, the gel is most often placed deep, in contact with the bone, to mimic its shape. Along the edge of the jaw, the plane can be more superficial: it depends on what is missing. At the practice, the gel is chosen from one of the two ranges used, Restylane or Hyafilia, according to the area.

Larger quantities

A small area usually needs about 1 ml. For the facial contour, 2 to 3 ml are usually needed, since we support a contour along its whole length, on both sides. This is one more reason to proceed in stages: the first time, we always do less, and we add if needed at the day-fifteen check-up.

More product is not necessarily better. Overfilling the hollow in front of the jowls, for example, can widen the chin.

The chin and the balance of the profile

The chin matters a great deal in the balance of a face. A classic guide is that, in profile, it reaches roughly the level of the lower lip. It is only a guide: we also look at the nose, the lips and the neck, from the front and in profile, on standardised photographs.

For the chin, hyaluronic acid has been assessed in randomised trials conducted with the manufacturers of the gels tested. In one of them, in adults with a mildly or moderately receding chin, 83% of treated people had a chin improved by at least one grade at three months, compared with 11% without treatment, and the difference persisted at one year. For the jawline, another trial found improved definition at six months in 69% of treated people, compared with 38% without treatment; treated people were then followed up to one year, with no comparison group beyond six months. At the practice, we expect six to eighteen months depending on the area and the person.

When a different approach is needed

• Significant skin laxity. Hyaluronic acid is mainly suited to mild to moderate loss of contour and laxity; beyond that, surgery is often more appropriate.
• Excess skin or fat in the neck. The gel supports a bony contour; it does not tighten the skin of the neck.
• A severely receding chin. Chin surgery then gives a more stable result over time.
• An asymmetry of bony or dental origin.

Safety

Along the jaw, no major vessel or nerve runs just under the skin, but the facial artery and vein, a branch of the facial nerve and the parotid gland are close by. At the chin, a small artery, the ascending mental artery, supplies the upper part of the chin: it enters on average 6 mm from the midline and 4 mm under the skin, with wide variation from one person to another, and blocking it can damage the tissues.

The injection point and depth are chosen according to these courses. No technique removes this risk: hyaluronidase and the emergency protocol are always at the practice, and the warning signs are explained in the article on the reversibility of hyaluronic acid.