Best toothpaste for sensitive teeth: what the ingredients do

Why teeth get sensitive

Under your enamel is a softer layer called dentin. It’s full of microscopic channels that run toward the nerve. When enamel wears thin or gums pull back, those channels are exposed, and heat, cold, and acidic or sticky foods can reach the nerve.

The American Dental Association lists these causes:

• Worn enamel.
• Exposed roots, when gums pull back.
• Gum disease.
• A cavity, a cracked tooth or a worn filling.

The first two are what a sensitivity toothpaste is made for. The last two need a dentist, and no toothpaste will fix them. For more on telling them apart, see tooth sensitive to cold.

What the ingredients do

Every sensitivity toothpaste has an active ingredient listed on the label. A 2023 review cited by the ADA found that brushing twice a day with a paste containing stannous fluoride, potassium (with or without stannous), or arginine can be recommended to reduce sensitivity pain. Here’s how they differ.

Potassium nitrate

This is the most common one. It’s thought to calm the nerve inside the tooth so it responds less to cold and heat. One leading brand uses 5% potassium nitrate alongside sodium fluoride for cavity protection. Its label says it “builds increasing protection” against sensitivity, which is a fair warning that it isn’t instant.

Stannous fluoride

Stannous fluoride works differently. It leaves a thin layer over the dentin that plugs the open channels, so less reaches the nerve. It’s a fluoride too, so it also helps prevent cavities.

In one eight-week trial, stannous fluoride eased sensitivity sooner than potassium nitrate, with a difference in sensitivity to touch by day three. By week eight, both had worked well. That trial was funded by Procter & Gamble, which makes a stannous fluoride toothpaste, so treat the head-to-head result with some caution.

Arginine

Arginine is an amino acid used in some sensitivity toothpastes. The same 2023 review put it alongside the other two. If you choose one, the same rules apply: look for fluoride and the ADA Seal.

What to look for on the box

• A sensitivity active ingredient: potassium nitrate, stannous fluoride or arginine.
• Fluoride. Every toothpaste with the ADA Seal and a cavity claim must contain it.
• The ADA Seal of Acceptance. It means the company showed the ADA evidence that the paste is safe and does what it claims. The ADA also requires Seal toothpastes to be gentle enough on teeth, measured by a limit on abrasiveness.

Which ingredient is “best” matters less than using one every day. If one paste hasn’t helped after a few weeks, trying the other type is reasonable.

How to use it so it works

A sensitivity toothpaste only helps if it stays on your teeth long enough.

1. Brush twice a day, morning and night. The label on one leading brand says at least a 1-inch strip, for at least one minute, twice a day. Most people should aim for the full two minutes.
2. Use a soft-bristled brush and go gently. The label calls for a soft brush, and gentle brushing is easier on sensitive spots.
3. Spit, don’t rinse. The ADA recommends spitting out the extra toothpaste without rinsing with water. Leaving fluoride on your teeth helps enamel resist acid.
4. Give it a few weeks. The ADA notes it usually takes several brushings before sensitivity eases. The label allows four weeks, so judge it then, not after one night.
5. Keep using it while it helps. The label says twice a day, not just until the zing fades.

These pastes are labeled for adults and children 12 and older. For a younger child with sensitive teeth, ask a dentist first.

When sensitivity means see a dentist

The label on a leading brand is blunt about this. It says to stop and ask a dentist if sensitivity still persists after four weeks of use, or if it gets worse, because sensitive teeth may signal a serious problem.

See a dentist soon, rather than trying another tube, if:

• Pain from hot or cold lingers after the drink is gone.
• One tooth is getting steadily worse.
• It hurts to bite, or you see a chip, a crack or a dark spot.
• Your gums are swollen or bleed easily.

If a tooth is already throbbing, start with what to do for a toothache right now.

What a dentist can do, and what it costs

When a toothpaste isn’t enough, the ADA lists several in-office options:

• Fluoride gel to strengthen enamel and reduce sensitivity.
• Bonding, an inlay or a crown to fix a flaw or decay that’s causing the sensitivity.
• A gum graft to cover a root that has lost its gum.
• A root canal, only when sensitivity is severe, persistent and nothing else works.

The price depends on which of these you need, the tooth, where you live and your coverage, so ask for a written estimate first. If you don’t have dental insurance, a dental savings plan (a discount membership, not insurance) can lower the price at participating dentists.

How to keep it from coming back

• Keep brushing with the sensitivity toothpaste if it helps.
• Brush gently with soft bristles, twice a day. An electric brush with a pressure sensor warns you when you press too hard; see the best electric toothbrush.
• Clean between your teeth once a day to help keep gums healthy. See water flosser vs string floss.
• Cut back on sipping acidic drinks through the day.
• If you grind your teeth, ask your dentist about a night guard.
• Get regular checkups, so small problems are caught early.