Getting a dental filling is one of the most common procedures in dentistry, and a straightforward one. Most fillings take under an hour from start to finish, with simple cavities done in as few as 20 minutes. Here’s what the full process looks like, from recognizing you need one to walking out of the office.
Signs You Might Need a Filling
Cavities don’t always announce themselves. In the earliest stage, you might notice small white, chalky spots on a tooth. These are areas where minerals are leaching out of the enamel, and at this point, the damage can sometimes be reversed with fluoride treatments rather than a filling.
Once decay moves past that early stage, actual holes form in the enamel, and those white spots may turn light brown. You still might not feel anything. It’s only when decay reaches the softer layer beneath your enamel, called dentin, that sensitivity kicks in. Hot coffee, ice cream, or sugary foods start to sting. The spots on the tooth darken to a deeper brown. This is the stage where most people realize something is wrong and where a filling is the standard fix.
If a cavity is already causing real pain, that typically means decay has reached the innermost tissue of the tooth. At that point, you may need more than a filling. You might also notice swelling in the gums around the tooth, or dark brown to black discoloration. Pain that radiates into your jaw or face can signal an infection at the root, which requires more involved treatment. The takeaway: the earlier you catch it, the simpler and cheaper the fix.
What Happens During the Appointment
The process follows a predictable sequence, and understanding each step can take a lot of the anxiety out of it.
Numbing
Your dentist starts by rubbing a topical numbing gel on the gum near the tooth. This dulls the area so you barely feel the anesthetic injection that follows. The shot itself produces a brief pinching or pressure sensation, sometimes with a feeling of cold liquid spreading through the tissue. After that, you wait a few minutes for the area to go fully numb. From this point on, you’ll feel pressure and vibration but not pain.
Removing the Decay
The dentist uses a high-speed drill to access the cavity and remove the bulk of the decayed material. For softer decay closer to the nerve, they switch to a slower, more precise handpiece that preserves as much healthy tooth as possible. Once all the decay is gone, the remaining cavity is cleaned and sterilized to eliminate bacteria before filling.
Placing and Shaping the Filling
The filling material is placed into the prepared space and molded to match the natural grooves and contours of your tooth. Getting the shape right matters because even a slightly off bite will feel uncomfortable. For composite (tooth-colored) fillings, the dentist applies the material in layers and hardens each layer with a blue curing light. Amalgam (silver) fillings are packed directly into the cavity and shaped while still soft. Once the filling is in place, your dentist checks your bite and makes adjustments, then polishes the surface smooth.
Composite vs. Amalgam Fillings
The two most common filling materials have distinct tradeoffs. Composite resin fillings are made of a plastic and glass mixture that can be color-matched to your tooth, making them nearly invisible. They bond directly to the tooth structure and work well for small to medium cavities, especially on visible front teeth. The downside: they don’t last quite as long as amalgam, and they cost more.
Amalgam fillings are a blend of metals including silver, tin, copper, and about 50% mercury. They’re stronger, last longer, and cost less. A cost analysis comparing the two found that amalgam restorations have a longer lifespan on average, and the tooth is less likely to eventually need a crown or extraction. The tradeoff is cosmetic: they’re silver-colored and noticeable.
Amalgam does release tiny amounts of mercury vapor, particularly when a filling is placed or removed, or during habits like teeth grinding. The FDA notes that studies have not found conclusive evidence of harm in the general population, but does recommend that certain groups avoid amalgam if possible. These include pregnant or nursing women, children under six, people with mercury allergies, and those with neurological or kidney conditions. For everyone else, existing amalgam fillings that are intact do not need to be removed.
How Much a Filling Costs
Without insurance, a filling runs roughly $200 to $600 on average, though simple amalgam fillings on one or two teeth can be as low as $50 to $200. Composite fillings for one or two teeth typically fall between $150 and $300, climbing to $200 to $550 for three or more surfaces.
Most dental insurance plans cover fillings and will typically pay up to 80% of the cost after you’ve met your annual deductible. Amalgam fillings generally get full coverage without question. Some plans cover composite fillings only up to the cost of an equivalent amalgam filling, leaving you to pay the difference.
Recovery and What You Can Eat
Composite fillings harden instantly under the curing light, so the filling itself is ready to use right away. The real limitation is the numbness. Most dentists use lidocaine, which keeps your mouth numb for one to three hours. Other anesthetics can last longer, up to six hours in some cases. Eating while numb is risky because you can bite your cheek or tongue without realizing it. Wait until the feeling returns.
Once numbness fades, you can drink cool water and eat soft foods. Hold off on hot drinks like coffee or tea for two to three hours with composite fillings. If you got an amalgam filling, the material takes up to 24 hours to fully harden, so the rules are stricter: wait at least an hour before drinking water, and a full 24 hours before hot beverages, soda, acidic juices, or alcohol. Regardless of filling type, skip soda and sugary drinks for 24 hours.
Some sensitivity to hot, cold, or pressure around the filled tooth is normal for a few days to a couple of weeks. If your bite feels off when you close your jaw, or if sensitivity persists beyond two weeks, call your dentist. The filling may need a minor adjustment.
Drill-Free Options
Some dental offices now offer laser cavity preparation as an alternative to the traditional drill. Lasers can target decayed tissue precisely without vibration, noise, or the heat buildup of a drill. They sterilize the area as they work, which reduces infection risk. In some cases, you won’t need anesthesia at all, which means no numbness and a faster return to eating normally. Recovery tends to be quicker too, often within a day or two.
Lasers do have limits. They work best on small cavities and soft tissue procedures. Large cavities, decay between teeth, removing old fillings, or preparing a tooth for a crown still require a drill. Laser treatments also cost more, and not every insurance plan covers them fully. Availability varies, particularly outside major metro areas. Even practices that offer lasers keep traditional tools on hand for cases where a laser can’t finish the job. Another drill-free option, air abrasion, uses a stream of fine particles to remove very small or shallow decay, though it’s limited to minor cavities.
When a Filling Isn’t Enough
If more than half of a tooth’s chewing surface is compromised by decay, fracture, or an existing large filling, a crown is typically the better option. A filling in that scenario wouldn’t have enough healthy tooth structure to hold onto and would be prone to cracking. Crowns cap the entire visible portion of the tooth and provide structural support that a filling can’t. They require a separate, longer appointment and cost significantly more, which is another reason to address cavities while they’re still small enough for a simple filling.