Getting a filling causes little to no pain during the actual procedure for most people. The numbing injection beforehand is typically the most uncomfortable part, and even that lasts only a few seconds. Afterward, you can expect some sensitivity that peaks in the first day or two and fades over one to two weeks.
What the Procedure Actually Feels Like
Once the anesthetic kicks in, you shouldn’t feel pain from the drilling or filling itself. You’ll feel pressure, vibration, and the sensation of water spraying inside your mouth, but the sharp nerve signals are blocked. Small surface cavities can be filled in under 30 minutes with minimal discomfort. Deeper cavities take longer and sit closer to the nerve inside the tooth, which means there’s more potential for sensitivity even through the numbing.
The depth of your cavity is the single biggest factor in how much you’ll feel. A shallow cavity on the biting surface of a tooth is a straightforward fix. A deep cavity that extends close to the pulp (the soft tissue housing the nerve) requires more drilling to remove decayed material, and the closer the work gets to that nerve, the more likely you are to notice moments of sensitivity during the procedure.
The Numbing Injection
Most people dread the needle more than the filling itself. Your dentist will typically apply a topical gel to your gums first, though interestingly, a controlled trial published in Anesthesia Progress found that 20% benzocaine gel performed no better than a placebo at reducing injection pain. The good news: the injection itself is brief, and the sting fades within seconds.
Local anesthesia works well for fillings. Failure rates are higher for more complex procedures like root canals, where inflammation and infection can interfere with numbing. For a standard filling, the odds are strongly in your favor. That said, a few things can make the anesthetic less effective: teeth on the lower jaw are harder to numb due to the bone density around them, active inflammation or infection around the tooth can lower the local pH and reduce how well the anesthetic works, and high stress levels can amplify pain perception. If you’ve had trouble getting numb in the past, letting your dentist know ahead of time helps them adjust their approach.
Numbness in your lips, cheek, and tongue typically lasts three to five hours. The two most common anesthetics used in dentistry produce soft tissue numbness averaging about four and a half hours, so plan on feeling puffy and clumsy with that side of your mouth for a good chunk of your day.
Pain After the Filling
Post-filling sensitivity is normal and follows a predictable pattern. Discomfort peaks in the first 24 to 48 hours, with noticeable improvement by days three to five. Most people with shallow to moderate fillings feel completely normal within two weeks. Deep fillings near the pulp can take three to four weeks to fully settle down.
During this recovery window, you’ll likely notice sensitivity to hot and cold foods, a mild ache when biting down, or a twinge when air hits the tooth. These are signs of temporary inflammation in the pulp caused by the drilling, and they resolve as the tissue calms down.
One factor worth knowing: filling material matters. A study comparing amalgam (silver) and composite (tooth-colored) fillings found that amalgam restorations caused post-operative sensitivity in 18.1% of cases, while composite fillings caused it in just 9%. Most dentists now use composite resin for the majority of fillings, which works in your favor.
Signs Something Isn’t Right
A “high” filling is the most common fixable problem after the procedure. If your filling sits even slightly too tall, your bite won’t close evenly, and that one tooth absorbs more force than it should every time you chew. The symptoms are distinct: your teeth feel like they don’t fit together properly, you get a dull pressure or sharp pain when biting, and you may develop jaw soreness, headaches, or even earaches as your muscles compensate. The fix is simple. Your dentist shaves down the high spot in a painless adjustment that takes a few minutes.
Watch the trajectory of your pain rather than just the intensity. Mild sensitivity that gradually decreases is normal healing. But if your pain starts improving and then worsens again after three to four days, that reversed pattern can signal complications like pulp inflammation, bacterial contamination, or an undetected crack. Persistent, unchanged sensitivity beyond four weeks also warrants a call to your dentist.
Managing Discomfort at Home
Over-the-counter ibuprofen (400 mg) is the first-line recommendation for dental pain, based on current clinical practice guidelines. You can combine it with 500 mg of acetaminophen for stronger relief. This combination works well enough that prescription pain medication is rarely needed for fillings. If you can’t take ibuprofen due to stomach issues or other reasons, acetaminophen alone at 1,000 mg is the alternative.
Beyond medication, sticking to lukewarm foods and drinks for the first few days helps avoid triggering sensitivity. Chewing on the opposite side gives the tooth time to settle. Most people find that by the end of the first week, they’ve stopped thinking about the filling entirely.