Filling a cavity is one of the most common dental procedures, taking about 20 minutes for a simple filling and up to an hour for larger or more complex ones. The process involves numbing the area, removing decayed tooth material, packing the hole with a filling material, and shaping it to match your bite. Here’s what actually happens at each stage and what to expect before, during, and after.
What Happens During the Procedure
The process follows a straightforward sequence. First, your dentist numbs the tooth and surrounding gum with a local anesthetic, usually delivered by injection. You’ll feel pressure but shouldn’t feel pain once the area is fully numb, which takes a few minutes.
Next, the dentist removes all the decayed or damaged tissue from inside the tooth using a small drill or other specialized instruments. This is the part most people dread, but with proper numbing you’ll mainly hear the sound and feel vibration. Once the decay is cleared out, the dentist cleans the cavity to remove bacteria and debris, then fills the hole with the chosen material. If you’re getting a tooth-colored composite filling, the dentist hardens it in layers using a blue UV curing light. Silver amalgam fillings harden on their own over time and don’t need light curing.
Finally, the dentist polishes the filling, smooths any rough edges, and checks your bite by having you close your teeth together. If anything feels high or uneven, they’ll adjust it on the spot. The whole appointment typically runs an hour or less.
Types of Filling Materials
The material your dentist uses affects cost, appearance, and how long the filling lasts. The most common options are composite resin and silver amalgam, though a few others exist for specific situations.
- Composite resin is tooth-colored and blends in with your natural teeth. It’s the most popular choice for visible teeth and is hardened instantly with a curing light. It costs between $173 and $439 per tooth.
- Silver amalgam is a metallic alloy that’s been used for decades, especially on back teeth. It’s the least expensive option at $108 to $256 per tooth, though its silver-gray color makes it noticeable.
- Glass ionomer is another tooth-colored option, often used for fillings near the gum line or on baby teeth. It costs $116 to $285 per tooth.
- Gold and porcelain ceramic are premium materials. Gold runs $361 to $817 per tooth, while porcelain ranges from $755 to $1,774. These are less common for standard cavities.
The size of the cavity also affects cost. Larger cavities need more material and more time, and deeper ones may require additional steps to protect the nerve inside the tooth.
How Long Each Type Lasts
Amalgam fillings generally outlast composites, though both can last many years with good care. A large analysis of longevity data found a median survival time of 12.8 years for amalgam fillings compared to 7.8 years for composites. Other studies report longer numbers: one found amalgam lasting a median of 22.5 years and composites lasting 16.7 years. In a general dental practice setting, composite fillings in back teeth lasted a median of 16 years over a 17-year observation period.
The range is wide because longevity depends on where the filling is in your mouth, how large it is, your chewing habits, and how well you maintain your teeth. Back teeth take more force, so fillings there wear down faster. A small filling on a front tooth could easily last decades.
When a Filling Isn’t Enough
Not every cavity can be fixed with a filling. 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 crown covers the entire visible portion of the tooth and provides structural support that a filling alone can’t offer when too much natural tooth is gone. Your dentist will assess this before starting treatment.
What Recovery Feels Like
Some sensitivity after a filling is normal, particularly to hot, cold, or pressure. This typically fades within a few days to a few weeks. The sensitivity comes from several factors: the process of drilling into the tooth, how the filling material bonds to the tooth surface, and minor changes in how the tooth responds to temperature. It usually presents as a sharp, brief pain that goes away quickly.
If sensitivity persists beyond a month, or if your bite feels off when you close your teeth, contact your dentist. A filling that sits even slightly too high can cause ongoing discomfort, and the fix is a quick adjustment. Persistent sensitivity can also signal a problem with the seal between the filling and your tooth, which allows saliva and bacteria to seep underneath. Left unchecked, that can lead to new decay forming around the filling.
Eating and Drinking After Your Filling
Your aftercare timeline depends on which material was used. Composite fillings are fully hardened before you leave the office, so you can eat right away in theory. However, if your mouth is still numb from the anesthetic, it’s worth waiting at least 2 hours before chewing on that side to avoid accidentally biting your cheek or tongue.
Amalgam fillings take about 24 hours to fully harden and reach maximum strength. Your dentist will likely recommend avoiding chewing on that side for a full day. Stick to soft foods and chew on the opposite side during that window. For both types, avoid extremely hot or cold foods for the first day or two if you’re experiencing sensitivity.
Cost and Insurance
Dental filling costs range from $108 to $1,774 per tooth, with the material being the biggest variable. Most people getting a standard composite filling on a back tooth will pay somewhere in the $200 to $400 range before insurance. Silver amalgam runs roughly half that. Larger cavities cost more because they require additional material and time.
Most dental insurance plans cover fillings as a basic procedure, typically at 70% to 80% after your deductible. Some plans only cover amalgam for back teeth and require you to pay the difference if you choose composite. Check your specific plan before your appointment so the cost doesn’t catch you off guard.