Bleach, please: The dark side of teeth whitening

When Lavania Rosie booked a teeth whitening session at a dental salon in Bali during her August 2024 holiday, she never imagined she would come to regret it so profoundly.

The 40-year-old dance instructor had seen an ad for a popular chain on Instagram, touting whitening services at a fraction of the price in Singapore. While whitening treatments in Singapore typically cost around $950 and take up to two and a half hours, salons in Bali charge just $100 for treatments that last only 45 minutes.

“I just went with it; they looked legit and had a big following on Instagram,” she recalls. It turned out to be a painful mistake.

“The treatment completely stripped my enamel. Everything I ate or drank after that hurt — I survived on smoothie bowls for the rest of my trip,” she says. “Even brushing was excruciating. The pain lasted for about a month, but I’m still traumatised to this day.”

The whiter, the better

Cosmetic dentistry — particularly teeth whitening — is booming, both globally and in Singapore. According to London-based market research firm Technavio, the global cosmetic dentistry market is projected to grow from US$22.97 billion ($29.4 billion) in 2024 to US$45.94 billion ($58.8 billion) by 2028. 

And judging by what people are willing to do for pearly whites, that number might just be conservative. 

Social media is overflowing with tips and “miracle” hacks, from questionable products to downright dangerous methods. 

Case in point? One viral TikTok trend involved scrubbing teeth with a Mr. Clean Magic Eraser, which is essentially a melamine foam that acts like sandpaper. Yes, someone looked at a household cleaning block and thought: “Perfect… for my molars.”

Dr Lynette Ng, clinical director at The Dental Studio, has seen a growing number of patients chasing the perfect smile — and suffering the consequences. 

“Unfortunately, we’ve seen cases of chemical burns, gum damage, and long-term sensitivity,” she says. “Some patients have even worn away parts of their enamel due to repeated use of harsh or unapproved substances.”

She’s not alone. 

Dr James Ho, founder of GPlus Dental Center and G Dental Center, says he’s treated many patients with complications. 

“While most people can live with uneven colouring from DIY treatments, enamel erosion that causes sensitivity or gum irritation severe enough to be painful — that’s what drives them to seek help finally,” he explains.

His biggest concern? Gum injuries. 

“Prolonged contact with bleaching agents can lead to redness, swelling, and in some cases, chemical burns,” he warns. “It’s critical to visit a dental clinic promptly. The pain doesn’t just go away — you need professional care to treat the damage and prevent it from getting worse.”

The dark side of smile hacks

Gum damage from DIY hacks is something that Quinn Chen knows all too well.

Now 28 and the managing director of Ice’s Secret and Dr Hair by IceSecret, Quinn recalls how her obsession with teeth whitening began as a teenager — and how it almost went too far.
“It probably started when I was 14 or 15,” she says. “I was always on stage for school events and performances, so I became very aware of how I looked under those bright lights.”

What followed was a years-long experiment with nearly every whitening method she could get her hands on — many of which were not dentist-approved. 

“I started with the usual teenage hacks. Strawberries and baking soda — which tasted awful, by the way — and then those brush-on pens where you had to freeze your smile like you were drying nail polish,” she says. 

“Later, I ordered take-home kits from the US, complete with syringes and boil-and-bite trays. But some of those gels would sting like crazy, especially if they touched my gums. Some sessions were really uncomfortable, but I powered through thinking, beauty is pain, right?”

However, experts warn that many of these “natural” hacks are not only ineffective but also downright harmful.

“I know there’s a move towards natural remedies, but from a clinical perspective, the ingredients commonly used in these viral trends are neither safe nor scientifically proven to be effective,” says Dr Ho.

Take baking soda, for instance. While mildly abrasive, he notes that overuse can wear away the enamel — the protective outer layer of your teeth — leading to thinning, sensitivity, and increased risk of cavities.

Lemon juice, another fan-favourite in the DIY crowd, poses a different but equally damaging risk. 

“Citric acid is highly corrosive to enamel,” Dr Ho explains. “Repeated exposure can weaken your teeth, making them more prone to decay and stains, not to mention irritation to your gums.”
Experts agree that social media has played a significant role in turning bright, white smiles into a beauty standard. 

Dr Ho notes that Medigy, a healthcare tech research platform, captured this shift well, highlighting how the desire for whiter teeth in Singapore often reflects deeper associations with appearance, confidence, and credibility.

But if you’re serious about whitening, your safest bet is to head to the dentist — or, at the very least, use a reputable at-home whitening kit formulated by dental professionals.

These days, a casual stroll through the supermarket — or a few taps on an app — will turn up dozens of over-the-counter (OTC) whitening options promising pearly whites in under 30 minutes.

After the success of its Invisible Whitening Strips, homegrown dental tech brand Zenyum launched its new ZenyumBright Series, a curated line of Smile Cosmetics, in September 2024. Meanwhile, legacy smile brand Colgate went viral that same year with the launch of its Optic White Purple toothpaste, a colour-correcting formula designed to neutralise yellow tones from the very first brush.

Trust the professional

While over-the-counter options may be convenient and cost-effective, Dr Ng says there’s a reason professional whitening remains the gold standard.

“Professional whitening treatments are carried out under controlled conditions using peroxide-based gels,” explains Dr Ng. “These gels release oxygen that penetrates the enamel to break down stains within the tooth structure. The key is that they’re neutral in pH and don’t erode the tooth surface when used correctly.”

In a clinic setting, dentists use high-concentration peroxide (often around 25 per cent) and take protective measures to shield the gums and soft tissue from exposure. Some treatments may also use light or laser to accelerate the whitening process, all while being closely monitored by trained professionals.

“At-home options can also be safe and effective if they come from credible sources and are used properly,” adds Dr Ho. “The main difference is that OTC products contain lower concentrations of peroxide, which may deliver milder results, but they’re still useful for maintenance or those with minimal staining.”

However, for stains that run deeper, often caused by ageing, smoking, or long-term neglect, he emphasises that professional treatments are usually the more effective — and safer — route. 

He also adds, “One thing is certain: if you have concerns about tooth sensitivity, gum health, or the potential impact of whitening on existing dental work like fillings or veneers, you should always consult a dentist first.”

He cautions against salon services that claim to offer professional-level whitening.
Unless a licensed dentist is involved, they legally shouldn’t be using high-strength peroxide,” Dr Ho warns. “That’s why these treatments carry significant risks — especially when untrained personnel are applying chemicals close to your gums.”

Trust the professional

Before even signing up for a whitening treatment, Dr Ng urges consumers to do their homework. “Check the credentials of the provider and ensure a licensed dental professional is involved,” she advises. 

“Ask what type of product is being used, whether an examination is done beforehand, and what aftercare is provided. Whitening may not be suitable for everyone, especially those with crowns, veneers, or underlying dental conditions. An informed decision is the safest decision.”

Dr Ho adds that there’s another often-overlooked factor to consider: the alignment of your teeth.
“Many people don’t realise that the position of your teeth — whether they’re straight, crowded, or slightly rotated — can significantly affect the whitening process,” he explains.

According to him, misaligned or overlapping teeth can lead to uneven whitening because the surface area exposed to the whitening agent isn’t uniform.

“When teeth are crowded or overlap, some areas may not receive enough gel or light exposure during treatment,” he says. “That means you might end up with patchy results — whiter on the outer surfaces and duller or stained in the areas that were shielded.”

And if whitening is already part of your routine, Dr Ng advises watching out for a few clear warning signs that it’s time to hit pause.”

“If you’re experiencing persistent sensitivity, sharp pain, or notice white patches or burns on your gums, that’s definitely a red flag. Your teeth might also appear uneven in colour or look glassy and translucent — signs that enamel erosion may have started,” she warns. “These symptoms often mean the product was too strong, misapplied, or used too frequently.”

At some point, Quinn made a quiet decision: she was done.

“A couple of years after my whitening phase, I thought about doing it again — just a little touch-up,” she recalls. “But this time, the dentist told me something unexpected: my teeth were already at their natural whitest.”

The suggestion surprised her. The dentist explained that pushing beyond that point would mean turning to veneers — and she strongly advised against it.

“That moment really stuck with me. It was the first time someone reminded me that it’s okay to stop chasing ‘whiter’ and start appreciating what I already have,” says Quinn. “Thankfully, I hadn’t done any serious damage. I think I was lucky to have met someone who gave me honest advice instead of selling me a procedure.”

Today, she’s shifted her mindset.

“I used to think a beautiful smile was all about brightness and symmetry. Now, I believe it’s more about energy and expression. The most beautiful smiles are the ones that come from joy,” she says.

Perhaps it’s time we rethink our obsession with gleaming, uniform, Hollywood smiles — and take a cue from a growing number of celebrities who are redefining beauty on their own terms. British actress Aimee Lou Wood has spoken candidly about loving her “wonky little teeth”, while Wicked star Cynthia Erivo proudly rocks her gap-toothed grin.

These women — and many others — remind us that imperfection can be a powerful force. In an age of hyper-optimised aesthetics, where even teeth have to audition for approval, there’s something oddly radical about choosing to leave them alone.

And if someone insists you could look better with a bit of bleaching, you could always flash them a smile and politely show them the door, with enamel intact.