Why Do My Teeth Feel Sensitive When Using Whitening Gels – But Some People Don’t?
Teeth whitening has become one of the most popular cosmetic dental treatments in the UK as many people now seek a brighter, whiter smile.
But if you’ve tried whitening, you may have noticed something: while your friends or family breeze through treatment without a problem, your teeth feel sensitive. You might experience a sharp twinge when drinking something cold, a dull ache during treatment, or a lingering discomfort after removing your trays.
So why does whitening sensitivity affect some people and not others? And, more importantly, what can you do about it? Let’s take a closer look.
How Whitening Gels Work
To understand sensitivity, it helps to know how whitening works. Whitening gels usually contain hydrogen peroxide or carbamide peroxide. These ingredients release oxygen, which penetrates the enamel and breaks down stains within the tooth.
This process doesn’t damage the tooth structure, but it does open tiny pathways in the enamel called dentinal tubules. These tubules connect to the inner part of the tooth, where the nerves live. When they’re exposed, cold, hot, or pressure changes can trigger sensitivity.
Why Do Some People Get Sensitive and Others Don’t?
Not everyone experiences the same level of sensitivity during teeth whitening. The reasons are a mix of individual biology, dental health, and lifestyle factors.
- Thickness of Enamel
People with naturally thinner enamel are more likely to feel sensitivity. Enamel is the protective outer layer of the tooth, and if it’s worn down or thin, the whitening gel penetrates more quickly to the sensitive dentine beneath.
- Pre-existing Sensitivity
If your teeth are already sensitive before teeth whitening treatment, you’re more likely to notice discomfort during treatment. Conditions like gum recession, worn enamel, or microscopic cracks can make teeth reactive.
- Concentration of Whitening Gel
Professional whitening gels come in different strengths. Some people tolerate higher concentrations of peroxide without issue, while others may need a lower-strength gel to reduce discomfort.
- Individual Pain Threshold
Just as some people feel the dentist’s drill more acutely than others, pain perception plays a role in whitening sensitivity. What feels like a mild tingle for one person may feel like a sharp ache for another.
- Dental Health and Gum Condition
Exposed root surfaces (from receding gums) or leaky fillings can increase sensitivity, as the gel reaches areas not protected by enamel.
- Lifestyle Factors
Habits such as frequent acidic food and drink consumption (like citrus fruits, wine, or fizzy drinks) can weaken enamel, making teeth more sensitive during whitening.
What Does Whitening Sensitivity Feel Like?
Patients often describe whitening sensitivity as:
- A quick, sharp “zing” or “twinge” in the teeth
- A dull, achy feeling that comes and goes
- Increased reaction to hot or cold food and drinks
- Sensitivity during the whitening process itself or shortly after removing trays
The good news is that sensitivity is temporary. It usually subsides once treatment is complete, or even within a few days of stopping whitening.
How to Manage and Prevent Whitening Sensitivity
If you’re worried about sensitivity – or you’re already experiencing it – there are many steps you can take to make whitening more comfortable and Inspired Dental Care is here to advise you on it:
- Use Desensitising Toothpaste
Switching to a toothpaste designed for sensitive teeth (such as Sensodyne, Colgate Sensitive Pro-Relief or specific paste provided with the teeth whitening system) a few weeks before whitening can reduce discomfort. These toothpastes block the tiny tubules in enamel, reducing nerve response.
- Apply Desensitising Gel
Some professional whitening systems (like
- Alternate arches in Whitening Sessions
If you experience sensitivity, try and apply gel to one arch only and alternate. Even alternating session can still achieve great results over time, it will just take longer.
- Take Breaks
It’s perfectly fine to skip a night or two if sensitivity is bothering you. Whitening results are cumulative, so taking a short break won’t ruin your progress.
- Avoid Cold Foods and Drinks
During whitening, avoid ice-cold drinks, frozen treats, or very hot foods, as these can trigger discomfort. Stick to lukewarm or room-temperature options.
- Check Tray Fit
Ill-fitting trays can leak gel onto gums, causing irritation and increasing discomfort. Custom-made trays from your dentist minimise this risk.
- Talk to Your Dentist
If sensitivity is severe, your dentist may recommend a lower concentration of whitening gel, a different system, or specific aftercare products.
Professional Whitening vs Over-the-Counter Products
It’s worth noting that professional whitening systems are designed with sensitivity management in mind. At Inspired Dental Care in Exeter, we only use dentist-approved systems such as Enlighten, which include desensitising gels and customised protocols.
Over-the-counter products, on the other hand, may use ill-fitting trays or strips, higher concentrations of peroxide systems that are not professionally prescribed are illegal as there is no control over the ingredients. These can increase the risk of sensitivity or even damage if used incorrectly.
When to Seek Help
While sensitivity is normal during whitening, you should contact your dentist if:
- The pain is severe and doesn’t improve after a break from treatment
- You notice gum irritation, burning, or sores
- A tooth feels persistently sensitive even weeks after finishing whitening
- You suspect an underlying dental issue, such as decay or a cracked filling
Your dentist can check whether whitening is the true cause of the problem or whether another issue needs attention.
How Inspired Dental Care Can Help
At Inspired Dental Care in Exeter, we understand that every smile – and every patient – is unique. Some of our patients breeze through whitening without a second thought, while others need a little extra support. Here’s how we can help:
- Comprehensive assessment: Before starting whitening, we’ll check your oral health, enamel thickness, and gum condition to predict whether sensitivity is likely;
- Tailored whitening plans: We use professional systems such as Enlighten, which come with a B1 shade guarantee and built-in sensitivity management;
- Supportive aftercare: We provide desensitising products and practical advice to help you stay comfortable throughout treatment;
- Adjustments as needed: If you experience sensitivity, we can alter your treatment plan – whether that’s shorter wear times, lower-strength gels, or a break in treatment;
Our goal is not just to give you a whiter smile, but to make sure you achieve it safely, comfortably, and with confidence.
Final Thoughts
Teeth sensitivity during whitening is common, but it doesn’t happen to everyone. Factors like enamel thickness, pre-existing sensitivity, lifestyle habits, and even individual pain thresholds all play a role.
If you do experience sensitivity, rest assured it’s temporary – and there are many ways to reduce it. With professional whitening systems, desensitising products, and guidance from your dentist, you can enjoy a brighter smile without unnecessary discomfort.
At Inspired Dental Care in Exeter, we’re here to guide you every step of the way – from preparing your teeth for whitening to managing sensitivity and achieving long-lasting results. Because a whiter smile should never come at the expense of your comfort.
