Wisdom teeth: when they need to come out, and when you can keep them

Wisdom teeth are the last teeth to come through, usually between 17 and 25, one in each corner of the mouth. For some people they arrive without trouble and stay for life. For others there isn't room, they grow at an angle or stay half under the gum, and that's when the problems start.

The question we hear most is simple: “Does it need to come out?” The honest answer is: it depends. Here's why.

When you can keep it

A wisdom tooth can stay if:

• it has come through fully and stands upright, in line with the other teeth;
• it bites normally against the tooth on the opposite jaw;
• you can clean it well with a brush and floss;
• it has no decay and the gum around it is healthy.

In that case a wisdom tooth is a tooth like any other. We keep an eye on it at your usual check-ups and treat it if needed, just like the rest.

When it's better out

Extraction is usually recommended in these situations:

• Repeated inflammation of the gum around it (pericoronitis). Gum partly covering the tooth traps food and bacteria, swells and hurts, and the episode keeps coming back.
• Decay in the wisdom tooth or the tooth in front of it, hard to treat because the area is hard to clean and reach.
• A tilted tooth pushing on or hitting the molar in front and putting its root at risk.
• Cysts or other changes in the bone around a tooth that stayed in the bone.
• Lack of space before orthodontic treatment, on the dentist's advice.

Once one of these problems appears, it usually doesn't go away. And an extraction done in time, before a big infection, is simpler and heals more easily.

How we tell

We don't decide by eye. At the consultation we look at the gum and how your teeth bite, then take a panoramic X-ray, which shows all four wisdom teeth, their position and their roots. For lower ones, especially when they're close to the nerve that gives feeling to the lip, we also take a CBCT scan, which shows in three dimensions how close the roots are to the nerve.

On these images we show you what we see and tell you honestly whether an extraction makes sense now, later or not at all.

How the extraction goes

It's done under local anaesthetic, so you feel pressure, not pain. A fully erupted wisdom tooth usually comes out like any other tooth, in a few minutes. An impacted one, partly or fully in the bone, needs a small procedure: we open the gum and sometimes divide the tooth into pieces, to remove it with as little pressure on the bone as possible. We usually finish with a few stitches.

We tell you every step beforehand. If you're nervous, tell us at the start: fear of extractions is one of the most common reasons patients put treatment off, and putting it off usually makes things harder.

Recovery

The first two or three days are the least pleasant. It's normal to have:

• cheek swelling that peaks on the second or third day;
• some difficulty opening wide for a few days;
• discomfort that eases with the recommended painkiller.

The first day matters most for healing: keep the gauze pressed, don't rinse, spit, smoke or drink through a straw, so the clot stays in place. If the pain eases and then comes back stronger after the second or third day, it may be a dry socket: call us, it's easily treated. Everything, day by day, is in Recovery after a tooth extraction.

Plan a quieter day or two after an impacted wisdom tooth. We remove the stitches at a check-up, usually after about a week.

The risks, plainly

The most common complication is a dry socket, and following the first-day instructions makes it less likely. With lower wisdom teeth, the roots can be close to the nerve of the lip, and rarely there is numbness of the lip or chin, usually temporary. That's why we plan on the X-ray and tell you beforehand if the risk is higher in your case.

Common questions

Does wisdom tooth removal hurt?

Not during the extraction: we work under local anaesthetic. Once it wears off there's some discomfort for a few days, which eases with the recommended painkiller.

Do all four have to come out at once?

Not necessarily. We remove the ones causing problems. Sometimes it makes sense to take out two on the same side in one visit, so you can chew on the other side while it heals.

At what age is it best to remove them?

When it's needed, healing is usually easier when you're younger, because the roots aren't fully formed. But we don't remove a tooth with no problems just in case.

If a wisdom tooth is bothering you, or you'd like to know what position yours are in, a consultation and an X-ray give you the answer. More at Extractions and wisdom teeth.