You’ve got your custom trays, your whitening gel, and you’re ready to start. Now, how do you actually get the best out of this?

There’s a difference between following the basic instructions and genuinely optimising your whitening experience. Here’s what I tell my patients to get the most out of their treatment.

Start on a Good Day

This might sound oddly simple, but timing matters. I recommend patients start their whitening course on a Thursday or Friday evening. Why? Because the first couple of sessions are when you’re most likely to notice any sensitivity, and having the weekend to rest from whitening (if needed) without disrupting your week is genuinely useful.

Don’t Skip the Prep

If I’ve recommended you use a sensitivity toothpaste before starting, use it. Consistently, for at least two weeks beforehand. Brush and floss before each whitening session to ensure the tray fits cleanly against the tooth surface. Gel needs direct contact with the enamel to work.

Fill the Trays Correctly

A common mistake: using too much gel. You only need a small amount, a tiny dot per tooth space in the front section of the tray. The trays are designed to hold the gel against the tooth; you don’t need to fill the tray. Overfilling leads to gel overflow onto the gums and wasted product.

Day vs Night Whitening: Which Is Right for You?

Most professional home whitening systems offer two options:

• Night whitening: Lower concentration gel worn for a longer period (typically 6–8 hours, overnight). Generally well-tolerated and convenient for people who prefer wearing trays while they sleep.
• Day whitening: Higher concentration, shorter wear time (45–90 minutes during the day). Better for people who can’t comfortably sleep in their trays, or who want more control over timing.

Neither is universally “better”, it depends on your preference and sensitivity level. I’ll always recommend what I think suits you best.

What to Eat (and Avoid) During Your Whitening Course

During active whitening, stick to lighter-coloured foods as much as possible. Avoid the “chromogenic” foods: coffee, tea, red wine, dark berries, tomato sauce, soy sauce, and turmericheavy foods. Smoking significantly reduces whitening efficacy and stains resin quickly.

After your whitening course, you can relax the dietary restrictions, but being mindful of staining habits will help your results last longer.

How to Maintain Your Results

Professional whitening results typically last 1–3 years. The simplest maintenance approach: a “topup” week of whitening every 6–12 months using your existing trays and a new tube of gel. This is very affordable compared to a full whitening course, and it keeps your shade consistent.

Your hygienist can also help maintain the surface brightness of your teeth with professional polishing at your regular appointments.

When Results Are Less Than Expected

If after completing your full whitening course you haven’t achieved the results you hoped for, it may be that a longer course or higher concentration is needed, or that some types of staining (particularly tetracycline staining) are more resistant to whitening and may require a different approach.

Don’t be disheartened, book a follow-up conversation. We’ll look at what else can be done.