Sensitive Teeth: Why They Hurt and What to Do

The pain from sensitive teeth is unmistakable — a sharp, sudden jolt triggered by something cold, sweet, or as simple as breathing in cool air. It spikes and fades, and most people learn to work around it. What’s less well known is that sensitivity is a symptom, not an inevitable part of having teeth, and most causes are treatable once identified.

What Is Tooth Sensitivity?

Sensitive teeth hurt because the pain comes from the dentine underneath the enamel. The dentine contains thousands of tiny tubules that lead directly to the nerve in the middle of the tooth.

Under normal conditions, enamel or gum tissue insulates these tubules. When that insulation is compromised, external stimuli reach the nerve more easily — producing the sharp, brief response that characterises sensitivity.

Cold is the most common trigger, but heat, sweet foods, acidic drinks, cold air, and sometimes direct pressure can all produce the same response. Pain that spikes and fades within seconds is typical.

Pain that lingers beyond 30 seconds after the trigger is removed, or that’s present without any obvious cause, suggests something more than simple dentine sensitivity.

Why Are My Teeth Sensitive?

Enamel erosion

Acid wears enamel down over time. Dietary acids — soft drinks, citrus, sports drinks, vinegar-based foods — are the most common source.

Stomach acid from reflux causes the same damage, often more severely, affecting the inner surfaces of the teeth. Enamel doesn’t grow back, so unchecked erosion leads to worsening sensitivity over time.

Gum recession

When gum tissue pulls back, the root surface is exposed. The root has no enamel — only a thin, minimally protective layer called cementum. Root sensitivity is typically sharp and localised, and more pronounced than sensitivity on the crown of the tooth.

Cracked tooth

A crack allows stimuli direct access to the nerve. Sensitivity from a crack is usually concentrated in one specific tooth and may also be triggered by biting pressure. If sensitivity is sharp and localised, a crack is worth ruling out.

Teeth grinding

Bruxism wears enamel down steadily, often without the patient realising. Sensitivity from grinding tends to be diffuse — affecting multiple teeth rather than one — and is often accompanied by morning jaw soreness or flattened tooth surfaces.

Worn or failing fillings

Old fillings develop cracks or gaps at their margins over time, exposing the dentine beneath. Sensitivity that appears around an existing restoration, particularly an older one, is a reason to have the filling assessed.

Recent dental work or whitening

Sensitivity following a filling, scale and clean, or whitening treatment is common and usually temporary. The tooth settles over days to weeks. If it worsens rather than improves, or persists beyond a month, it should be reviewed.

Home Care That Can Help

Home care helps manage mild sensitivity and slow progression. It doesn’t fix structural problems — a crack, active decay, or ongoing gum recession needs professional treatment.

Desensitising toothpaste

Products containing potassium nitrate or stannous fluoride are the most evidence-backed option. Potassium nitrate calms the nerve; stannous fluoride blocks the dentinal tubules.

Results build over four to six weeks of consistent use. Applying a small amount directly to the sensitive area after brushing — rather than rinsing it off — improves the effect.

Soft-bristled toothbrush

Switch from a medium or hard brush if you haven’t already. Firm bristles wear enamel at the gumline and accelerate recession. Use gentle circular brushing motions rather than scrubbing back and forth. It’s better at cleaning your teeth and helps protect your gums and enamel.

Diet adjustments

Reduce how often you consume acidic foods and drinks — frequency of exposure matters more than quantity. Rinse with water after consuming something acidic and wait at least 30 minutes before brushing.

Managing grinding

If bruxism is suspected, reducing caffeine and alcohol in the evening can decrease grinding activity. A nightguard fitted by your Casula dentist is the effective long-term solution.

When to See a Dentist

Mild, generalised sensitivity that responds to desensitising toothpaste within a few weeks can often be managed at home. These situations need professional assessment:

• Sensitivity in a specific tooth — localised sensitivity suggests a structural cause, such as a crack, cavity, or failing restoration, that home care won’t resolve.
• Sensitivity that’s getting worse — progressive sensitivity indicates an ongoing cause that needs to be identified and stopped.
• Pain that lingers after the trigger is removed — sensitivity that persists beyond 30 seconds points to nerve involvement beyond simple dentine hypersensitivity
• Sensitivity triggered by heat as well as cold — heat sensitivity is a stronger indicator of pulp inflammation and needs prompt assessment
• Sensitivity with swelling, visible cracks, or a darkened tooth — these signs alongside sensitivity indicate something that needs clinical attention, not more desensitising toothpaste

Don’t wait for pain to become severe. The earlier the cause is identified, the more straightforward the treatment.

Treatment Options

Fluoride application

Professional fluoride varnish applied directly to sensitive areas strengthens enamel and seals exposed dentinal tubules more effectively than home fluoride products—a simple, non-invasive first step for generalised sensitivity.

Bonding agents

For localised sensitivity from enamel loss or exposed root surfaces, a bonding agent seals the dentine and provides a physical barrier between the nerve and external stimuli—more durable and targeted than home desensitising products.

Nightguard

For patients with bruxism, a custom-fitted nightguard absorbs the force of grinding during sleep, preventing further enamel wear. Combined with fluoride treatment, it reduces sensitivity over time.

Gum graft

Where recession has exposed significant root surface and caused persistent sensitivity, a gum graft covers the exposed area with tissue, reducing sensitivity and stopping further recession at the site.

Treating the underlying cause

Where sensitivity is driven by decay, a crack, or a failing filling, restoring the tooth removes the pathway to the nerve and resolves the sensitivity at its source.

Frequently Asked Questions

Why are my teeth sensitive even though I brush regularly?

Brushing doesn’t protect against enamel erosion, gum recession, or grinding — all common causes of sensitivity that develop regardless of brushing habits. The cause needs to be identified before the right treatment can be applied.

Can sensitive teeth get worse over time?

Yes, if the underlying cause isn’t addressed. Enamel erosion and gum recession are progressive. Untreated decay advances toward the nerve. Sensitivity that’s worsening rather than stable is a reason to book an appointment.

How long does desensitising toothpaste take to work?

Four to six weeks of consistent daily use. Applying it directly to sensitive areas after brushing and leaving it on — rather than rinsing — improves effectiveness. No improvement after six weeks is a signal to seek professional assessment.

Is tooth sensitivity the same as a toothache?

Not quite. Sensitivity is typically sharp, brief, and triggered by a specific stimulus. A toothache is usually a dull, persistent ache that may throb and isn’t necessarily triggered by anything external. Pain that lingers after a stimulus or wakes you at night is more consistent with a toothache and needs prompt attention.

Can children have sensitive teeth?

Yes. Children’s enamel is thinner than adult enamel, making teeth more susceptible to sensitivity from acidic foods and drinks. Newly erupted permanent teeth can also be temporarily sensitive while the enamel matures. Consistent sensitivity in a child warrants a dental check.

Sensitive Teeth Treatment in Casula

If sensitivity is affecting how you eat, drink, or go about your day, it’s worth finding out what’s causing it.

At Casula Dental Care, we welcome patients from Casula and the surrounding areas of Liverpool, Prestons, Lurnea, and Moorebank.

Call us on (02) 9199 9695 or book online. You’ll find us at Shop 17A, Casula Mall, 1 Ingham Drive in Casula.