Whitening Sensitivity

Why It Happens

To lighten a tooth, the peroxide in whitening gel has to pass through the enamel and reach the stain inside. Enamel is slightly porous, and beneath it lies dentine, a softer layer criss-crossed by microscopic fluid-filled channels running towards the nerve. During a whitening session those channels become more responsive, so cold air, a cold drink or even brushing can trigger a quick, sharp twinge that passes in seconds. Some people also feel brief, random zings in a tooth or two, mostly in the first few days.

None of this damages the tooth. The enamel is not being worn away and the nerve is not being injured; the tooth is more responsive than usual for as long as the gel is at work, then returns to its usual self when the course ends.

How Long It Lasts

For most people, only for the duration of the course, easing within a few days of the last session. A session can leave a few hours of sensitivity behind, often at its worst the following day, which is why the second or third day of a course tends to feel the most noticeable. Across two to three weeks of Boutique, or the two home weeks of Enlighten, it can wax and wane. After the final session it dies away, and nearly everyone is back to normal within days.

A later top-up may bring it back briefly. The same measures help, and top-ups are short, usually just a few nights.

Who Is More Prone to It

Anyone can feel it, but people who already have sensitive teeth are more likely to. The usual reasons are gum recession, which exposes root surfaces that have no enamel covering; enamel worn down over years by scrubbing too hard, clenching or acidic drinks; hairline cracks; and old fillings whose edges have broken down. Untreated decay and gum disease make whitening uncomfortable, so we treat those beforehand.

That is precisely why your teeth and gums are examined before you whiten. If Dr Pei spots a likely cause of sensitivity, the plan can allow for it, by treating the cause, starting a sensitivity toothpaste early or adapting how you whiten. A single tooth that is already sharply sensitive before you begin needs looking at in its own right, because whitening will not cure it and may aggravate it. Our sensitive teeth guide goes through the causes.

What Helps

• Switch to a sensitivity toothpaste a fortnight ahead and keep using it through the course. After brushing, spit but do not rinse, which leaves the active ingredient in place, and dab a little onto any tender area before bed.
• Wear the trays for less than the maximum time at first, increasing it once your teeth are comfortable.
• Skip a night or two after a session that felt uncomfortable. Alternate nights take longer but reach the same place.
• Hold off on ice-cold food and drink for the time being, and drink through a straw.
• Do not brush straight after a session. Rinse with water, and brush gently with a soft brush roughly an hour later.
• Remove any excess gel that oozes from the trays rather than letting it sit against the gums.

On a bad evening, your usual headache painkiller is fine, taken as the pack directs. We can also apply a desensitising treatment at the practice, £15. For most people, one or two of these changes does the job.

Sore Gums Are Something Else

Gel left against the gum produces a separate kind of discomfort: a sore or whitened patch where it made contact. It can look alarming, but it normally clears within a few hours of the gel being wiped off. The cause is too much gel or a tray that does not fit well. Because our trays are made from an iTero Element scan of your own teeth, the gel stays on the enamel, and that is why we do not use generic trays. Stick to the amount of gel you were shown, remove any that escapes, and use slightly less if your gums felt tender last time. A patch that lingers, or gums that bleed, mean you should stop and get in touch.

When to Get in Touch

The normal kind of sensitivity is sharp, brief, triggered by cold and gone in seconds. Contact us if:

• It is strong enough to wake you or put you off eating
• A few days after stopping, it has still not settled
• A single tooth is much worse than the others, or is painful to bite on
• The ache carries on for minutes once the cold has gone
• Your gums look white, feel sore or bleed

Any of these may mean a cracked tooth, decay or an inflamed nerve, which would need its own treatment whether or not you were whitening. WhatsApp us on 07515 676150 or call 020 8788 6688 and we will tell you whether to carry on, change the routine or come and see us; call before 9.30am if you need to be seen that day, and for severe pain out of hours, ring NHS 111. Pausing costs nothing: the trays are yours, and you carry on where you left off.

Whitening If Your Teeth Are Already Sensitive

Usually possible, with some adjustments. For mild sensitivity, the toothpaste routine, briefer sessions and whitening on alternate nights are normally enough, and you reach the same shade, just a little later. If a particular tooth is sensitive for its own reason, perhaps an exposed root or a failing filling, dealing with that first usually makes the whitening easier too.

Dr Pei will assess you, explain what to expect and keep an eye on you as you go. Boutique home whitening is £350, or £315 for plan members, and Enlighten is £650; Boutique also comes with all our Invisalign and composite bonding packages.² If you would like to ask about sensitivity first, message us on WhatsApp.

Questions

This guide explains the options in general terms. Only an examination can tell you which of them suits your own teeth.