My tooth is sensitive after a filling. Which patterns need follow-up?

The short answer

Mild sensitivity after a filling is common, and most of it settles on its own. A tooth that twinges briefly with cold, with a breath of air or with something sweet, and then stops within seconds, is behaving the way a recently treated tooth often behaves. The signal that matters is the trend: sensitivity that is a little better each week is usually settling, while sensitivity that is unchanged or worse after a few weeks deserves a look.

Four patterns deserve a call to the office rather than more waiting:

• Pain when you bite or chew on the new filling that is not improving.
• Cold pain that lingers for many seconds or minutes after the cold is gone.
• Pain that starts on its own, wakes you, or throbs.
• Swelling of the gum next to the tooth or of the face.

These mean an examination is the right next step, because the causes range from a bite that sits slightly high to a nerve that is more inflamed than expected, and the fix is different for each.

Why a freshly filled tooth can be sensitive

Several things happen during a filling appointment that can leave the tooth reactive for a while:

• The tooth was cut and dried. Removing decay and shaping the cavity exposes dentin, the layer under the enamel. Dentin is riddled with microscopic fluid-filled tubules that run toward the nerve. When cold, air or sugar moves that fluid, the nerve registers it as a sharp, short pain. This is the same mechanism behind ordinary sensitive teeth, and it often calms over time as the tooth settles and the exposed dentin becomes less reactive.
• The material sits close to the nerve. The deeper the decay, the thinner the dentin left between the filling and the pulp (the tooth's nerve), and the more easily the nerve is irritated. If the decay was deep, the tooth may take longer to settle.
• The nerve was already irritated. Dental work can temporarily inflame the pulp. Dentists call the mild, recoverable form reversible pulpitis: the tooth reacts to cold but the pain stops within a few seconds once the cold is removed.
• The bite may be slightly high. Numbness makes it hard to judge your bite at the end of an appointment. If the new filling meets the opposing tooth a fraction earlier than its neighbors, every bite loads that tooth harder than usual, and it can ache or feel bruised. This is a common reason for pain on biting after a filling, and often a simple adjustment corrects it.
• Bonded materials are placed differently. Tooth-colored composite is bonded to the tooth with an adhesive and hardens in place, which makes its placement more technique-sensitive than amalgam (silver) fillings, which are packed rather than bonded. The quality of the bond, the dryness of the field and how the material is layered can influence how the tooth feels afterward. The material choices are explained in tooth-colored filling materials: the questions worth asking.

Pattern and urgency: reading what your tooth is telling you

A printable version of this table accompanies this guide. Three questions do most of the work: what sets the pain off, how long it lasts after the trigger is gone, and whether it is improving week to week.

Two companion guides go deeper: cold sensitivity that lingers and why one tooth hurts when you bite.

Why "lingering" is the key word

A short, sharp reaction to cold that stops as soon as the cold is gone is usually a nerve that is irritated but recovering. A reaction that keeps aching after the stimulus is removed, or that heat sets off, is the pattern dentists associate with a nerve that may not recover. Timing how long the ache lasts after a cold drink is a useful observation to bring to the office.

Why biting pain gets its own row

Pain on biting after a filling often has a mechanical cause rather than a nerve cause: the filling meets the opposing tooth first, there is a small gap at the margin where the filling meets the tooth, or a crack in the tooth was present before the filling and is now flexing. A crack can produce a sharp pain on release of biting pressure and may not show on an X-ray, so the dentist relies on how the tooth responds to biting on individual points.

What a follow-up visit checks

A follow-up for post-filling sensitivity is usually systematic:

• The bite. Marking paper shows whether the new filling contacts the opposing tooth harder than its neighbors. A high spot can usually be smoothed at the same visit, often without numbing; if biting pain does not ease afterward, the dentist looks for another cause.
• The margins. The dentist examines where filling meets tooth for a gap, a rough edge or a ledge that could be trapping fluid or food.
• A cold test. A cold stimulus is applied to the filled tooth and to a neighboring tooth for comparison. How quickly the pain starts and how long it lingers helps classify the nerve's condition.
• Tapping and bite tests. Tenderness to tapping, or to biting on one specific point of the tooth, points toward inflammation around the root tip or a crack.
• An X-ray if indicated. Radiographs are taken when the examination raises a question they can answer, such as the depth of the filling relative to the pulp or changes around the root tip, not routinely.

The adjustments that follow depend on what is found. A high bite is smoothed. A margin problem may mean polishing, sealing or redoing part of the filling. A tooth that shows signs of lingering nerve inflammation may be watched for a defined period, or the dentist may discuss further treatment. If the filling replaced an old amalgam, that appointment is described in what does an amalgam replacement appointment involve. Patients with a new crown rather than a filling have a parallel guide: why a new crown can feel different.

Safe self-care while you wait

• Chew on the other side and favor softer foods for a few days if biting is uncomfortable. If you cannot avoid the tooth without real effort, that is itself a reason to call.
• Use a toothpaste for sensitive teeth. These contain ingredients that calm the nerve response or block the dentin tubules, and they often take a couple of weeks of regular use to make a difference.
• Keep brushing the area gently with a soft brush so the filling margin stays clean.
• Limit very cold, very hot or very sweet items for a short time if they are the trigger, but keep eating normally otherwise.
• Over-the-counter pain relievers, used exactly as directed on the label, can help with aching; the ADA's guidance for acute dental pain favors non-opioid options. If you take other medications or have medical conditions, check with a pharmacist or physician first. Needing pain relief for more than a day or two is a reason to call rather than to keep taking it.

When emergency care comes first

A filling does not usually lead to an emergency, but the signs of a spreading infection should not wait for a dental appointment or an online form. Call 911 or go to the nearest emergency department if you have:

• difficulty breathing or swallowing;
• swelling of the face or neck that is spreading quickly;
• fever together with facial swelling;
• uncontrolled bleeding or a severe injury to the mouth or jaw.

These are medical emergencies first. Dental follow-up comes afterward.

How to describe the pattern when you call

The office can triage far better with specifics than with "it hurts." Call during office hours, Monday to Thursday 8:00 am to 5:00 pm, or use the appointment request page for anything that is not urgent; a request is not a confirmed appointment and the team follows up. When you call, be ready to say:

• which tooth was filled and when;
• what sets the pain off (cold, heat, sweet, biting, nothing);
• how long it lasts after the trigger is gone, in seconds or minutes;
• whether it is better, the same or worse than the week before;
• whether there is any swelling, a bad taste or a feeling that the tooth is higher than the others;
• what you have already tried.

Ask the office whether a bite check for a recent filling is scheduled differently from a regular visit, and what to do if the pattern changes before you are seen. The practice's check-up and emergency care services are listed on the services page.