Can Bone Grow Again After Square Jaw Surgery?

Hello. I am Dr. Jo Hyun-woo of Ipche Surgical Clinic.

Today, I would like to talk about something a little different, rather than a surgical explanation.

I think this is probably the question most people who have had, or are planning to have, facial contouring surgery are most curious about.

Can bone grow again after square jaw surgery?

To get straight to the point, the bone that has been cut away does not grow back.

Sometimes patients come in and ask, “After square jaw surgery, does the bone grow again? Can it return to its original state?”

Whenever I get that question, I answer firmly that no, that will not happen.

If we follow patients for 1 year, 2 years, or 3 years and take CT scans, in most cases the jawbone hardly changes at all.

After surgery, the cut surface of the removed bone becomes smoother and is covered over to some extent.

Recently, a patient who had square jaw surgery came to the hospital after 3 years, and while taking follow-up CT images, I came across a truly surprising case.

Before surgery

6 months after surgery

The first photo is the patient’s preoperative image, and the second photo is from 6 months after surgery.

But when I looked at the image taken 3 years after surgery, I saw that the bone had grown downward.

Square jaw surgery involves resecting the mandibular angle of the jaw, and at the same time, cortical osteotomy may be performed to reduce bone thickness.

In cases where the muscles are very developed or thick, masseter reduction surgery may also be performed at the same time.

At this time, after square jaw surgery, the muscles can redevelop in proportion to how often and how strongly they are used, but the resected bone does not grow back.

Bone does not literally “grow” in the way we think of tree sap.

Instead, growth factors in the bone, which are easier to imagine as something like sap, come from osteoblasts, and when we suffer a fracture or after cheekbone surgery, the cut bone surfaces join and fuse together.

3 years after surgery

The case above, where the bone appeared to have grown, was the first one I had seen in 15 years.

This patient did not come in because the newly grown bone was visible or caused discomfort.

The amount of bone growth was also very subtle, only about 2 to 3 mm.

After seeing this real case, I looked through many papers and case reports, but I could not find any similar examples.

I also searched extensively overseas on Google, but there was nothing written about this as an issue.

However, one thing is clear!! There is a possibility that the bone could grow again.

That said, even if it is only 0.1%, it may appear as though bone is protruding because of factors coming from the bone itself.

If you had square jaw surgery and the bone seems to protrude or feels noticeable, and this happened years later, it may be worth considering this possibility.

The chance of bone developing again after square jaw surgery is extremely low, but if you enjoy chewy and hard foods like gum or dried squid, or if you have a habit of clenching your teeth, the muscles may gradually become more developed after surgery.

In conclusion, the reason for changes in the bone is probably that the masticatory muscles attached to the square jaw area affect the jawbone when chewing, but nothing is completely certain.

I will study this a little more and gather more cases before sharing again.

Today, I talked about a patient whose bone grew again after square jaw surgery.

This is not something that applies to most patients at all, but I hope you can view it as one possible case.

Thank you.