Sensitive after whitening? Why it happens and what helps

Feeling a twinge when you sip something cold after whitening is very common, and for most people it fades within a few days. Understanding why it happens makes it less worrying, and a few simple steps can make the next day or two more comfortable. Here’s what usually helps, and when it’s worth a call.

Why whitening can cause sensitivity

Whitening gels use peroxide to break down stains inside the tooth. To do that, the gel passes through the enamel into the layer beneath, called dentin. Dentin contains tiny channels that lead toward the nerve, and while the peroxide is working, it can temporarily make the nerve more reactive.

The result is usually a short, sharp feeling with cold air, cold drinks or sometimes sweet foods. Some people also notice brief twinges that come and go without any obvious trigger. For most people it settles once whitening stops and the tooth has had a little time to calm down.

Sensitivity tends to be more likely if your teeth were already sensitive, if you have receding gums or exposed roots, if there are small cracks or worn areas in the enamel, or if whitening products are used more often or for longer than directed.

This kind of sensitivity is different from the ongoing sensitivity some people have from worn enamel or exposed roots, although whitening can make an existing problem more noticeable for a while. Gums can also become irritated if gel touches them, which usually shows up as soreness or pale patches that fade within a day or so.

For most people, sensitivity after whitening is a passing reaction, not a sign of harm.

What eases it at home

• Brush with a toothpaste made for sensitive teeth, ideally starting before whitening and continuing for a while afterward.
• Avoid very hot, very cold and very acidic foods and drinks for a day or two.
• Let cold drinks warm up a little, or use a straw to keep them away from the most sensitive teeth.
• Brush gently with a soft brush and lukewarm water.
• If you’re using an at-home kit, take a break or space sessions further apart until things settle.
• An over-the-counter pain reliever you normally take without problems may help, used as the label directs.

Toothpastes for sensitive teeth often contain potassium nitrate, which helps calm the nerve, or ingredients that help block the tiny channels in dentin. They usually work best with regular use over several days or weeks rather than as a one-off. Your dentist may also suggest a fluoride product applied to the teeth.

Making the next round more comfortable

If whitening left you uncomfortable, that doesn’t necessarily mean you can’t whiten again. It often helps to use a lower-strength gel, to keep sessions shorter or less frequent, or to pause for a few days between treatments. Follow the instructions for any product exactly, and don’t leave gel on longer in the hope of faster results. It rarely speeds things up and often makes sensitivity worse.

Before starting, it’s worth having a checkup. Whitening on top of untreated decay, a leaking filling or receding gums is more likely to be uncomfortable, and those problems are worth addressing anyway. A dentist can also tell you whether your type of staining is likely to respond, which saves trying a product that won’t help.

Over-the-counter strips and gels vary in strength and fit. Trays that don’t fit well can let gel spread onto the gums and cause irritation. If you’ve had trouble with one product, it’s worth talking to a dentist before trying another.

When to call the practice

Mild, short-lived sensitivity is expected and usually needs nothing more than patience and the steps above. It’s worth giving the practice a call if:

• Sensitivity lasts more than a few days after you’ve stopped whitening.
• The pain is severe or throbbing, or it keeps you awake at night.
• One tooth hurts much more than the others, which can point to a crack, decay or a problem with a filling.
• Your gums look white, sore or irritated where the gel touched them and don’t settle within a day or two.

If you’re partway through a course of whitening and sensitivity keeps building, it’s usually better to pause and ask than to push on and hope it passes.

If you’re unsure whether what you’re feeling is normal, a quick call is always fine. Reach Artistic Dentistry at (610) 779-0911, describe what’s going on, and we’ll help you decide on the next step.