The truth about teeth whitening: what actually works

A brighter smile is one of the most common requests we hear at Impact Dental Centre. But with so many products and treatments available, it can be hard to know what actually works — and what's just marketing.

Why do teeth lose their whiteness?

Before diving into solutions, it helps to understand why teeth discolour in the first place. The most common causes include:

• Food and drinks — Coffee, tea, red wine, and berries contain pigments that cling to enamel over time.
• Tobacco use — Both smoking and chewing tobacco cause stubborn yellow-brown stains.
• Age — Enamel thins naturally as we age, revealing the yellowish dentin beneath.
• Medications — Certain antibiotics (like tetracycline) and antihistamines can cause internal staining.

Over-the-counter options: do they work?

Whitening toothpastes, strips, and LED kits are everywhere. Here's the reality:

Whitening toothpaste uses mild abrasives to remove surface stains. It can help maintain whiteness, but won't dramatically change your shade. Look for the CDA Seal of Recognition.

Whitening strips (like Crest Whitestrips) use a low concentration of hydrogen peroxide. They can produce noticeable results over 1–2 weeks, but the fit isn't custom, which can lead to uneven whitening or gum sensitivity.

LED whitening kits often make bold claims, but most consumer LED devices don't produce enough light energy to meaningfully accelerate the whitening process.

"The best whitening approach is one that's supervised by your dentist. We can customize the treatment to your teeth and address any sensitivity before it becomes a problem."

— Dr. Goli Khorsandian

Professional whitening: the gold standard

Professional whitening remains the most effective and safest option. At Impact Dental Centre, we offer two approaches:

In-office whitening

Done in a single appointment, in-office whitening uses a higher concentration of bleaching agent applied under careful supervision. Results are immediate — typically 3–8 shades lighter in about an hour.

Custom take-home trays

We create custom-fitted trays from impressions of your teeth, paired with professional-grade whitening gel. You wear them at home for 30–60 minutes daily over 1–2 weeks. The custom fit ensures even coverage and minimizes gum irritation.

What about sensitivity?

Tooth sensitivity during whitening is common but manageable. Here's what helps:

• Use a sensitivity toothpaste (with potassium nitrate) for two weeks before starting treatment
• Avoid very hot or cold foods during the whitening period
• Take breaks between sessions if sensitivity increases
• Talk to your dentist — we can adjust the concentration or treatment time

Things to avoid

We recommend steering clear of:

• Charcoal toothpaste — Overly abrasive, can damage enamel permanently
• DIY remedies (lemon juice, baking soda pastes) — The acidity erodes enamel
• Unregulated products — Some online products contain unsafe levels of hydrogen peroxide

Ready for a Brighter Smile?

If you're considering whitening, the best first step is a dental exam. We'll assess your oral health, identify the type of staining, and recommend the safest, most effective approach for your goals.