Sensitive Teeth: 7 Common Causes and How Dentists Find the Real Issue

If drinking something cold, eating ice cream, or even running a toothbrush over your teeth causes a sharp twinge, you’re far from alone. Sensitive teeth are one of the most frequent issues patients raise with their dentist, and the discomfort can vary from a mild irritation to sudden, intense pain. What often catches people out is that sensitive teeth aren’t a condition on their own, they’re a sign that something else is going on. In some cases, the cause is straightforward and easily treated. In others, sensitivity can point to an underlying dental problem that needs professional care. In this guide, we’ll look at the seven most common reasons for sensitive teeth, how dentists identify the real cause, and what can be done to relieve the discomfort.

What Are Sensitive Teeth?

Sensitive teeth usually occur when the tooth’s natural protective layers stop doing their job properly. Under the enamel lies dentine, which contains microscopic tubules that connect directly to the tooth’s nerve. When dentine becomes exposed, everyday triggers such as hot drinks, cold foods, sugary treats, or acidic items can cause sudden pain.

It’s also worth knowing that sensitive teeth aren’t always caused by enamel wear alone. Gum health, how your teeth meet when you bite, older fillings, and even habits linked to stress can all contribute. That’s why persistent sensitivity should be properly assessed by a dentist, rather than relying on trial-and-error solutions at home.

The 7 Most Common Causes of Sensitive Teeth

1. Enamel Damage from Over-Brushing

Good oral hygiene is important, but brushing too firmly can actually contribute to sensitive teeth. Using a hard toothbrush or applying too much pressure can gradually wear down enamel and push the gums back, leaving vulnerable areas exposed.

This often happens to people who are keen to look after their teeth but haven’t been shown a gentle, effective brushing technique.

2. Receding Gums

As gums recede, the tooth roots can become exposed. Unlike the crown of the tooth, roots aren’t protected by enamel, which makes them far more reactive to hot, cold, and touch.

Gum recession can develop for several reasons, including brushing habits, gum disease, smoking, and age-related changes.

3. Teeth Grinding or Jaw Clenching

Grinding or clenching the teeth, known as bruxism, can slowly wear down enamel and place repeated stress on the teeth. Over time, this can expose dentine and irritate the tooth’s nerve, leading to sensitive teeth.

Many people don’t realise they grind their teeth until a dentist notices signs such as flattened edges or tiny cracks. Thankfully, there are effective treatment options available, including bite guards and BTX injections to reduce muscle activity.

4. Tooth Decay or Fine Cracks

Decay and hairline cracks can allow temperature changes and pressure to reach the nerve inside the tooth. Sensitivity caused by decay often begins subtly and becomes more noticeable over time, particularly when eating or drinking something sweet.

Cracks can be especially tricky, as they may not show up easily and can only cause discomfort when biting down or releasing pressure.

5. Acid Wear from Food, Drink, or Reflux

Regular consumption of acidic foods and drinks, such as fizzy drinks, citrus fruits, and sports beverages, can weaken enamel over time. Acid reflux and frequent heartburn can have a similar effect, particularly on the inside surfaces of the teeth.

Acid erosion often results in generalised sensitive teeth rather than pain isolated to one specific area.

6. Sensitivity After Dental Treatment

It’s very common to experience sensitive teeth following dental procedures such as fillings, crowns, whitening, or professional cleaning. In most cases, this sensitivity settles as the tooth and surrounding tissues recover.

If the discomfort doesn’t improve or worsens, it’s important to have it checked to rule out any underlying issues.

7. Ageing or Failing Dental Restorations

Over time, older fillings, crowns, and veneers can begin to loosen or develop microscopic gaps. These spaces allow bacteria and temperature changes to reach the tooth beneath, which can trigger sensitivity or pain.

This is one of the reasons regular dental check-ups remain important, even when everything appears fine on the surface.

Who Is Most Likely to Experience Sensitive Teeth?

Sensitive teeth can affect people of all ages, but they’re more commonly seen in:

• Adults between 20 and 50

• People with current or past gum disease

• Patients who grind or clench their teeth

• Those with acidic diets or acid reflux

• Individuals with multiple fillings or crowns

• People who brush too hard or use abrasive toothpaste

If sensitive teeth are starting to interfere with eating, drinking, or brushing, it’s a sign the issue shouldn’t be ignored. Addressing the cause early is far more likely to save discomfort, time, and expense than simply trying to mask the symptoms.

How We Diagnose the Real Problem

Dental care shouldn’t rely on guesswork. When it comes to sensitive teeth, the key is understanding why the discomfort is happening and addressing the cause rather than simply treating the symptoms. That’s why our approach focuses on careful assessment followed by a clear, personalised plan.

How We Identify the Cause of Sensitive Teeth

1. Understanding your symptoms We start by talking things through. You’ll be asked when the sensitivity occurs, what triggers it, how intense it feels, and whether it has changed over time.

2. Thorough dental examination Your dentist will assess the condition of your enamel and gums, check your bite, and review any existing dental restorations that could be contributing to sensitive teeth.

3. Targeted sensitivity checks Gentle tests, such as controlled airflow or temperature changes, help identify exactly which teeth are affected and how severe the response is.

4. X-rays where appropriate If needed, X-rays allow us to look beneath the surface for signs of decay, cracks, or problems under fillings that may not be visible during a routine exam.

5. Bite and grinding review We assess how your teeth meet and look for indicators of grinding or clenching, which are common but often overlooked causes of sensitive teeth.

6. Clear explanation and next steps Once the cause is confirmed, we explain everything in straightforward terms and outline a treatment plan tailored to your specific needs and goals.

This structured approach helps ensure treatment is precise, effective, and focused on long-term comfort, not temporary fixes.

Treatment Options for Sensitive Teeth

Treatment depends entirely on what’s causing the sensitivity. Depending on your assessment, options may include:

• Specially formulated toothpaste or in-clinic desensitising treatments

• Fluoride applications or protective sealants

• Gum care treatments and brushing technique advice

• Bite guards for grinding or clenching

• Repair or replacement of worn or leaking fillings

• Early treatment of decay

• Dietary guidance to reduce acid-related enamel wear

Once the underlying issue is addressed, many cases of sensitive teeth improve noticeably within a few weeks.

Why Proper Diagnosis Matters

Correctly diagnosing sensitive teeth offers several long-term benefits, including:

• Relief that lasts, rather than short-term masking

• Reduced risk of further tooth damage

• Greater comfort when eating and drinking

• More predictable treatment outcomes

• Conservative solutions that preserve natural teeth

• Reassurance that serious problems haven’t been missed

What Results Can You Expect at M Dental?

For straightforward cases, improvement in sensitive teeth can often be felt within days or weeks. More complex situations, such as grinding or gum recession, may require treatment in stages, but most patients experience steady progress once the cause is controlled.

Our aim is always to restore comfort while protecting your teeth for the future.

Additional Information

Sensitivity assessments are usually carried out as part of a routine dental examination, and appointments can be booked directly through our website.

Treatment costs vary depending on the findings of your assessment and your individual needs. This will be fully discussed during your consultation, along with a personalised treatment plan. Finance options are also available and can be explored via our website.

A Real Patient Experience

“I assumed I just had sensitive teeth and needed a different toothpaste. After my appointment, it turned out I was grinding my teeth in my sleep and wearing them down. Once everything was explained and I was fitted with a night guard, the sensitivity settled within weeks. I only wish I’d booked sooner."

Connor, Canary Wharf

If sensitive teeth are affecting your everyday comfort, don’t ignore it. Book a consultation with M Dental and let us identify the real cause. Early assessment often means simpler treatment, better results, and a healthier, more comfortable smile.

Are sensitive teeth permanent? In most cases, no. Once the underlying cause of sensitive teeth is identified and treated, the discomfort often reduces significantly or disappears altogether.

Can sensitive toothpaste solve the issue by itself? Sensitive toothpaste can ease symptoms, but it doesn’t fix deeper problems such as tooth decay, grinding, or gum recession that may be causing sensitive teeth.

Why do I only have one sensitive tooth? Sensitivity affecting a single tooth often suggests a localised problem, such as a small crack, cavity, or a filling that’s no longer sealing properly.

Does tooth sensitivity mean I need a root canal? Not usually. The majority of cases involving sensitive teeth don’t require root canal treatment. A thorough examination helps determine whether more advanced treatment is needed.

Can teeth whitening make sensitive teeth worse? Teeth whitening can cause temporary sensitivity in some people, but this typically settles within a few days once treatment is complete.

Is it possible to reverse gum recession? Gum recession can’t usually be reversed, but it can be managed and prevented from worsening with the right care and treatment.

Should I avoid cold foods and drinks if I have sensitive teeth? Avoiding triggers may help in the short term, but identifying and treating the cause of sensitive teeth is the most effective long-term solution.

When should I see a dentist about sensitive teeth? If sensitivity lasts longer than a week, becomes more intense, or starts affecting daily activities, it’s best to book a dental appointment sooner rather than later.