How Dentists Fix Cavities: A Step-by-Step Guide to Dental Fillings

That sinking feeling when your dentist gently says, “Well, it looks like you have a cavity…”—it’s one most of us know all too well. Maybe you’ve felt a sharp twinge when sipping something sweet. Or maybe you just saw a dark spot in the mirror and now you have all sorts of questions:

How does a dentist fix a cavity? Will it hurt? What should I expect during and after the visit?

If this sounds like you, you’re in the right spot. Cavities (also called dental caries) are very common—kids, adults, pretty much anyone with teeth get them. Knowing exactly what goes on during a dental filling can help you relax and feel ready.

In this guide, we’ll walk you through all about how dentists fix cavities. You’ll learn:

• What happens during a filling
• The different types of filling materials (yes, you have choices!)
• How pain is handled
• What happens after the filling
• And how to stop cavities before they start

Let’s get started (and yes, pun intended)—and help you feel ready and calm for your next appointment.

What We’ll Cover:

• What Is a Cavity and Why Fix It?
• Diagnosis: How Dentists Spot Cavities
• Step-by-Step: The Cavity Filling Process
• Types of Dental Fillings: Your Options Explained
• What to Expect After a Filling—and How to Care for Your Tooth
• Prevention: Keeping Cavities at Bay
• Key Takeaways and Next Steps

What Is a Cavity and Why Fix It?

Why did my dentist say I have a cavity? Is this usual?

Don’t worry—you’re not the only one. The CDC says about 90% of adults will get at least one cavity in their lives, and almost half of kids have one by kindergarten.

A cavity is just a tiny hole that shows up in your tooth when germs (bacteria) eat sugars in your mouth and make acid that eats away the outer part of your tooth (enamel). If you don’t fix it, it just gets bigger, going deeper into the tooth—this can cause pain, infection, or you might even lose the tooth.

Think of it like a pothole in the road: At first, it’s small and easy to cover. But if you leave it, the hole gets bigger, rougher, and a lot harder (and more expensive) to fix! That’s why dentists say to fix it right away.

Why can’t I fix a cavity at home?

Once the hole breaks through your tooth’s outer layer, you can’t just “brush it away.” Your body can’t grow that hard layer back. A dentist has to clean out the bad bit and fill in the space.

What’s the point of a filling?

A dental filling is like a super patch kit:

• It takes away the bad part (the decay)
• Makes the tooth whole again
• Closes up the spot to stop more decay
• Stops your tooth from hurting or getting infected

If you don’t fix it, the cavity just keeps getting worse.

Diagnosis: How Dentists Spot Cavities

Before a dentist can fix a cavity, they have to find it—which isn’t always easy! Many new cavities are hidden and don’t hurt at all.

How Do Dentists Find Cavities?

1. Looking in Your Mouth:

Dentists use a small mirror and a bright light to look for dark spots or rough places—usually in the grooves of your back teeth.

2. Dental Tool (Explorer):

This thin, pointy tool pushes gently on places that look “off.” If it feels soft or sticky, it might be a cavity.

3. Dental X-rays:

X-rays help dentists find cavities hiding between teeth or under old fillings—places a mirror can’t see.

Most of the time, dentists find cavities early, before you feel anything at all. That’s why checkups matter!

What Happens Next?

When your dentist finds a cavity, they’ll talk to you about:

• How big it is and where it is
• What your choices are (like what filling they can use)
• The price and if your insurance helps

Worried or have questions? Ask away! Dentists are used to it—they want you to understand what’s happening.

Step-by-Step: The Cavity Filling Process

Here’s what most people really want to know:

What really happens in the dentist’s chair when they fix a cavity?

Here’s the step-by-step, so you know what to expect.

Step 1: Numbing the Area

First, your dentist gets your tooth numb—usually with a shot that stings for a second, then goes away fast.

• How does it feel?

Most people say it’s just a little pinch, and soon everything’s numb.

• How long will I be numb?

Usually 1–3 hours—enough time to finish the work. Try not to bite your cheek or lip while you wait for it to wear off!

Don’t worry too much about pain—modern numbing works really well. Most people feel nothing but a weird vibration or some pressure.

Step 2: Keeping the Tooth Dry

The dentist keeps your tooth dry, because fillings need a dry spot to stick right.

• Dental Dam: A little rubber blanket covers the area.
• Cotton Rolls & Suction: These help soak up spit.

Step 3: Taking Away the Decay

Now the dentist takes out the bad part—usually with a tiny, loud drill that sprays water to keep the tooth cool.

• Does the drill hurt?

Not with the numbness—you’ll just feel the vibration, not pain.

• Why do they drill more than just the dark part?

So the filling stays in place and all the decay is gone.

Suction hoses suck away bits and water as the dentist works. The sound or feeling might be a little annoying, but it’s over fast.

Step 4: Getting the Tooth Ready (For Tooth-Colored Fillings)

If you’re getting a white filling (composite), they’ll:

• Put on a special gel: This makes the tooth tiny and rough, so the filling holds.
• Wash and dry: Makes a clean, dry surface.
• Add bonding glue: This sticky stuff helps hold the filling on. They set it with a blue light.

Step 5: Putting in the Filling

Now comes the main part:

• The dentist puts in the filling material (composite or another type).
• For white fillings, it goes in thin layers—each one is made hard with a blue light.

This helps it fit tight and look nice.

Step 6: Shaping and Polishing

When it’s hard:

• The dentist shapes the filling so your bite feels normal.
• You may bite down on some colored paper—this finds high spots.
• Then they smooth and shine it.

That’s it! The whole thing usually takes 20–60 minutes per tooth. Small cavities can be even quicker.

Types of Dental Fillings: Your Options Explained

This is where you can help pick what’s best for you—because not all fillings are the same.

Composite Resin (White Fillings)

What is it?

A mix of strong plastic and glass bits, made to look like your real tooth.

Pros:

• Blends in—super hard to spot
• Sticks right to your tooth
• Works anywhere in your mouth

Cons:

• Costs more than silver fillings
• Might stain or wear out faster if the filling is big

Lasts: 5–10 years (with care)

Amalgam (Silver Fillings)

What is it?

A mix of metals (mostly silver, tin, copper, and a tiny bit of mercury), used for a long time.

Pros:

• Very strong—good for back teeth where you chew
• Cheaper

Cons:

• Easy to spot (silver color)
• Has mercury (ADA says it’s safe)
• Can be sensitive to hot or cold

Lasts: 10–15 years or more

Gold Fillings

What is it?

Special gold fillings, often for molars.

Pros:

• Super strong—lasts a really long time
• Easy on other teeth

Cons:

• Expensive
• Gold color stands out (some people like it, some don’t)
• Usually takes two visits

Lasts: 15–30 years

Ceramic (Porcelain) Fillings: Inlays & Onlays

These are high-quality fillings, often made at a lab, and glued onto the tooth.

Pros:

• Looks just like your tooth
• Doesn’t stain and is tough

Cons:

• Costs more
• Can chip more easily than gold
• Usually takes at least two visits

Glass Ionomer Fillings

What is it?

A white filling that lets out fluoride slowly.

Pros:

• Fluoride can help stop more decay
• Good for kids or areas where you don’t bite hard

Cons:

• Not as strong as other kinds
• Often used for baby teeth or as a short-term filling

How do you choose?

Ask your dentist! They’ll help you pick based on where the hole is, how big it is, your budget, and what your insurance covers. Sometimes, only one type really fits your tooth or bite.

What to Expect After a Filling—and How to Care for Your Tooth

Ever wonder, “Will my tooth ache after a filling?” or “When can I eat?”

Here’s what usually happens right when you get home and later on.

Right After: What’s Normal?

Still Numb

• Your lip, cheek, and tongue may feel puffy or tingly. That goes away in a few hours.
• Don’t eat chewy or hot foods until you feel normal—so you don’t bite yourself.

Soreness or Sensitivity

• Your tooth might be a little sore or feel funny, especially if the filling was deep.
• Some people get a little ache when biting or with hot/cold for a day or so.
• Most times, regular pain meds (like Tylenol) help.

When Should I Call My Dentist?

Call your dentist if you notice:

• Pain that gets worse or doesn’t go away
• Swelling or a pimple on your gums
• A high spot or weird bite (sometimes the filling just needs a little shaping)
• A filling that’s loose, broken, or falls out

How to Make Fillings Last

• Brush and floss every day. Cleaning around your filling keeps new holes from forming.
• Don’t bite hard things like ice, pens, or your nails.
• See your dentist for checkups every 6 months.
• Eat less sugar and soda. These make more acid and can hurt fillings at the edges.
• Fillings won’t last forever. They may need fixing or replacing if they wear down, chip, or if more decay starts along the sides.

Prevention: Keeping Cavities at Bay

Good news: Most cavities can be stopped before they start. A few habits can keep your teeth healthy and limit the number of fillings you’ll ever need.

How to Stop Cavities

• Brush twice a day with fluoride toothpaste for at least two minutes.
• Floss daily to clean between teeth.
• Cut down on sugar and drinks like soda or juice.
• See the dentist for regular cleanings and x-rays.
• Sealants are a great option. Easy coating for back teeth—great for kids and adults who get lots of cavities.
• Ask about fluoride treatments. Extra fluoride can help make teeth tougher against cavities.

If you or your child have special tooth needs—like a dry mouth, braces, or soft enamel—ask your dentist what else you can do.

Key Takeaways and Next Steps

To sum up:

• Getting a cavity is normal—almost everyone will need a filling at some point.
• Getting a filling is simple, shouldn’t hurt, and brings your tooth back to normal.
• You have filling choices—just ask your dentist which is best for you.
• Keep your mouth clean—brush, floss, and see your dentist—to help fillings last.
• Don’t worry about your next dental visit. Knowing these steps can help you feel calm and ready.

What should you do next?

If you want to know about the cool side of dental work, fillings and crowns are often made by techs at great labs. For top results, check out expert places like a china dental lab, digital dental lab or crown and bridge lab.

Frequently Asked Questions

Q: Can a small cavity go away on its own?

A: Once a hole forms in the tooth, it won’t fix itself. Very early “white spots” might stop or get better with fluoride, but real cavities need a dentist to repair them.

Q: How long do fillings last?

A: Based on the filling type and how you care for them:

• Amalgam: 10–15+ years
• Composite: 5–10 years
• Gold: up to 30 years
• Ceramic: 10–15 years

Q: I’m scared of pain. Will it hurt?

A: With modern numbing and gentle dentists, getting a filling is almost always pain-free. If you’re nervous, tell your dentist—they can help even more, or offer medicine to help you relax.

Q: How much does a filling cost?

A: Most times, $50–250 for silver, $90–450 for white fillings, depending on how big the hole is, which tooth it’s on, and your insurance.

Taking care of a filling is just like your natural teeth. Good habits save you pain, time, and money!

If you’re overdue for a checkup or want a second opinion, book with your trusted dentist today.

Your future self—and your smile—will be glad you did.

Sources & More Reading

• American Dental Association: Fillings
• Centers for Disease Control and Prevention: Oral Health
• World Health Organization: Oral Health Fact Sheet

Keep smiling—you’ve got this!