Square Jaw Surgery: What Are a Retracted Jaw and a Protruding Jaw?

Hello, I’m Dr. Jo Hyun-woo of 입체성형외과.

There are two major concerns for people who come in for square jaw surgery.

Some want to get rid of a square jaw that looks angular from the side, while others are worried about a jaw that looks wide from the front.

Of course, there are also many people who want both.

Today, I’d like to talk about how square jaw surgery should be approached in order to create the face you want.

First, the square jaw I’m referring to is one that looks angular from the side.

CT and side view of a patient whose square jaw angle is 90 degrees

As you can see in these photos, this patient’s square jaw is very prominent from the side.

As I mentioned before while reviewing a paper in the past,

it is said that the ideal square jaw angle is 120 to 130 degrees, and in cases like this, if you simply trim the jaw angle properly, it can be changed to an ideal angle from the side.

Case in which cheekbone surgery, square jaw surgery, masseter muscle resection, and chin surgery were performed for side and front effects

In fact, this kind of surgery is the basic set of procedures for square jaw surgery.

It produces dramatic results and has a high level of satisfaction.

When I first started performing surgery, there were many patients with such a pronounced square jaw, but these days, when I see people coming in for consultations, many of them hardly have any angle on the side.

They want to keep some angle on the side while becoming slimmer from the front.

This is where the concepts of a retracted jaw and a protruding jaw come in.

Let me show you two CT scans.

(Left) Retracted jaw, (Right) Protruding jaw

As you can see, when looking at the CT from the front, some people have the square jaw angle curling inward, while others have it extending outward a lot.

When trimming the angle of the square jaw, if you trim the angle in people with a protruding jaw, you can see a dramatic effect from the front as well.

Even though only the bone was cut, the face becomes much slimmer from the front.

Case in which a dramatic front-view effect was achieved with square jaw surgery and cortical bone shaving in a protruding jaw

However, as I mentioned earlier, these days there are many people whose jaw angle is not very pronounced.

Even if someone has a protruding jaw, there are cases where there is no angle that can be trimmed.

In such cases, surgeries used to create a front-view effect include cortical bone shaving, masseter muscle resection, and cheek fat liposuction.

This CT image is what is called a coronal view of the facial bones.

It is a cross-section created by cutting vertically from the front.

In this image, you can see the square jaw bone, the lateral cortex, the muscle in the gray area, and the dark gray fat layer at the outermost side.

Let me show you this patient’s 3D images.

Cases where almost no side angle can be trimmed

This is a square jaw with a slightly protruding feeling.

From the side, the angle that can be trimmed is really only 2 to 3 mm.

In such cases, you can perform surgery to remove the lateral cortex seen in the coronal view I mentioned earlier by shaving it down.

You can also perform masseter muscle resection to remove some of the masseter muscle surrounding the outside.

Case in which 230-degree 3D cheekbone surgery and cheekbone + cheek fat liposuction were performed for a front-view effect

Next, cheek fat liposuction can also be performed.

To achieve a front-view effect, it seems best to combine several procedures rather than relying on bone alone in order to maximize the result.

As I mentioned earlier, if someone has a protruding jaw and the side angle is about 90 degrees, square jaw surgery alone can produce a very dramatic effect.

If the jaw is retracted, even if the side angle of the square jaw can be reduced, the front-view effect will hardly change.

Therefore, when performing square jaw surgery, I think it is very important to carefully observe your square jaw bone and decide on the surgery that is right for you.

If you simply think that cutting only the bone for a square jaw will make the face slimmer, there is a high chance you may be dissatisfied with the results after surgery.

The shape of the bone, the amount of masseter muscle, and the amount of fat cannot actually be determined just by looking from the outside.

For those who want a smaller angle from the side and a slimmer look from the front, it may be more satisfying to get a CT scan and carefully analyze your face, even if it is a little inconvenient.

Thank you.