Dental fillings are one of those “quiet hero” treatments: they fix a problem, stop sensitivity, and let you chew normally again—then you basically forget they’re there. But fillings aren’t meant to last forever. They live in a tough environment (temperature swings, chewing pressure, grinding, acidic foods), and over time they can wear down, loosen, or develop tiny gaps that invite new decay.
If you’ve ever wondered how long your filling should last—or why a tooth that was “fixed” years ago is suddenly acting up—you’re not alone. This guide walks through realistic lifespan ranges for different filling materials, what makes them fail sooner, and the signs that it’s time to have one checked and possibly replaced.
One important note: the goal isn’t to scare you into treatment. Most filling issues are manageable when caught early, and a quick replacement is usually far easier (and less expensive) than waiting until you need a root canal or crown.
What a dental filling is actually doing day to day
A filling isn’t just “patching a hole.” It’s restoring the shape and function of a tooth after decay or damage has been removed. Ideally, it seals the tooth so bacteria can’t sneak back in, and it rebuilds the biting surface so the tooth can handle normal chewing forces.
That sealing job is where things get interesting. Your mouth is warm, wet, and full of bacteria. Food particles stick around, acids come and go, and the tooth itself expands and contracts with hot coffee and cold water. Meanwhile, you might be biting down with hundreds of pounds of force—especially on molars. Over years, that constant stress can create microscopic changes at the edges of a filling.
Even if you brush and floss well, the edge where filling meets tooth (the “margin”) is a common weak spot. If that margin opens up, bacteria can start a new cavity underneath or around the filling, sometimes without obvious symptoms until it’s advanced.
Average lifespan: how long fillings typically last by material
Fillings come in different materials, and each has its own strengths. Some are tougher under heavy chewing, some look more natural, and some are chosen because they work well for certain cavity shapes. The lifespan numbers below are general ranges—your personal results depend on your bite, habits, and oral hygiene.
Also, “last” can mean different things. A filling might still be intact but start to leak at the edges. Or it might look fine but have decay developing underneath. That’s why regular dental exams and X-rays matter: they can catch issues before you feel them.
Composite (tooth-colored) fillings
Composite resin fillings are popular because they blend in with natural tooth color. They bond directly to the tooth, which can help support the remaining tooth structure and allow for more conservative drilling compared to older approaches.
In many cases, composite fillings last around 5–10 years, and sometimes longer with excellent care and a low-stress bite. They can wear down faster on large chewing surfaces, especially if you grind or clench. Composites can also pick up stain over time, which doesn’t necessarily mean failure—but it can be a cosmetic concern.
One more nuance: composites are technique-sensitive. Moisture control, proper bonding, and correct curing all matter. A well-placed composite by a careful clinician can last significantly longer than one placed under less-than-ideal conditions.
Amalgam (silver) fillings
Amalgam fillings have been used for decades and are known for durability, especially on molars. They don’t bond to the tooth the same way composites do, but they can handle heavy chewing forces well.
It’s common to see amalgam fillings last 10–15 years, and many people have them for 20+ years. That said, older amalgams can develop cracks in the surrounding tooth structure, partly because metal expands and contracts with temperature changes at a different rate than enamel.
Amalgam can also corrode slightly over time. Sometimes that corrosion can “self-seal” small gaps early on, but later it can contribute to breakdown at the margins. If you have a very old silver filling, it’s worth having it monitored even if it doesn’t hurt.
Gold and other cast-metal fillings (inlays/onlays)
Gold restorations and cast-metal inlays/onlays are less common today, mostly due to cost and aesthetics, but they’re famously long-lasting. These are typically lab-made restorations cemented into place.
When done well, gold can last 15–30 years or more. It’s strong, wears similarly to enamel, and tends to fit precisely. Many dentists consider it one of the best materials purely from a longevity standpoint.
The tradeoff is visibility and price. Still, if you have one already, it’s a good sign—those restorations often outlive other types when cared for properly.
Glass ionomer and resin-modified glass ionomer
Glass ionomer materials are often used for small fillings, areas near the gumline, baby teeth, or situations where moisture control is difficult. One of their benefits is fluoride release, which can help reduce the risk of future decay around the restoration.
In general, these fillings don’t last as long under heavy chewing forces—often 3–7 years depending on location and size. They can be a smart choice in certain clinical situations, but they may not be ideal for large biting surfaces in adults.
Some modern versions are improved, and your dentist may choose them strategically—especially for patients with high cavity risk or exposed root surfaces.
Why fillings fail sooner than expected
Sometimes a filling doesn’t reach its “average” lifespan, and it’s not necessarily because anything was done wrong. Teeth are complex, and the mouth is a demanding place. Understanding the common reasons for early failure can help you protect your restorations and avoid repeat repairs.
Think of filling longevity like tire longevity: driving habits, terrain, and maintenance matter just as much as the tire itself.
Chewing pressure, grinding, and clenching
Grinding (bruxism) is one of the biggest filling killers. It adds intense, repetitive forces that can crack a filling, fracture the tooth around it, or flatten the biting surface faster than normal wear.
Clenching can be just as harmful, even if you don’t hear grinding sounds. Many people clench during stress or while sleeping and don’t realize it until a dentist points out wear facets or cracks.
If you’ve had multiple fillings break or you notice jaw soreness in the morning, a night guard can be a game-changer. It’s not glamorous, but it protects both fillings and natural teeth.
New decay around or under the filling
Recurrent decay (a new cavity forming at the edge of an existing filling) is extremely common. It can happen when plaque sits along the margin, when flossing is inconsistent, or when the filling margin becomes rough or open over time.
Diet plays a role too. Frequent snacking, sipping sugary drinks, or constant exposure to acids (including sports drinks and citrus water) can keep your mouth in a cavity-friendly state for hours.
The tricky part is that recurrent decay can be painless until it gets deep. That’s why routine checkups and bitewing X-rays are so valuable—they can spot decay hiding between teeth or beneath old restorations.
Large fillings and weakened tooth structure
The bigger the filling, the more tooth structure has been removed—meaning the remaining tooth walls may be thinner and more prone to cracking. A small filling can last a long time because the tooth is still mostly intact. A large filling in a molar is working much harder.
When a filling replaces a big portion of the tooth, the tooth can act like a hollow shell. Over time, chewing forces can cause the walls to flex and eventually fracture. This is one reason dentists sometimes recommend an onlay or crown instead of “just another filling” when the cavity is large.
If you’ve been told a tooth needs more than a filling, it’s often about protecting the remaining tooth—not upselling. A protective restoration can reduce the risk of a sudden crack that leads to emergency treatment.
Moisture control and bonding challenges
Tooth-colored fillings rely on bonding systems that work best when the tooth is clean and properly isolated from saliva. Some areas of the mouth are harder to keep dry, especially near the gumline or in back molars.
If moisture contamination occurs during placement, the bond can be weaker, which may lead to sensitivity, marginal leakage, or early failure. This is one reason dentists use rubber dams or careful isolation techniques when possible.
That said, even a well-placed filling can fail early if the tooth is under high stress or if decay risk is high. It’s usually a combination of factors.
Signs your filling may need replacement (and what they can mean)
Your tooth doesn’t always send a clear “replace me” message. Sometimes the first sign is subtle, like a rough edge you feel with your tongue. Other times it’s a sharp zing when you bite down. Paying attention to these early clues can help you address problems while they’re still small.
Below are common signs, along with what they might indicate. None of these automatically mean you need a replacement, but they do mean it’s worth getting checked.
Sensitivity to cold, sweets, or air
Some sensitivity right after a new filling can be normal, especially with composites, and it often resolves within a few days to a couple of weeks. But sensitivity that starts months or years later is a different story.
Cold sensitivity can suggest a gap at the margin, exposed dentin, or recurrent decay. Sweet sensitivity can also point to early decay or a compromised seal. If the sensitivity is brief and goes away quickly, it may be mild irritation—but it still deserves attention.
If the sensitivity lingers or intensifies, that can mean the nerve is becoming inflamed. At that stage, prompt evaluation can sometimes prevent the situation from escalating.
Pain when biting or chewing
Pain on biting is a classic sign of a crack in the tooth or a high spot on the filling. A high spot means the filling is slightly too tall, so it takes the first hit when you bite. That can bruise the ligament around the tooth and create a sharp, localized pain.
A cracked tooth can be harder to diagnose because the pain may come and go, and it can be triggered by certain foods or angles of pressure. Sometimes the crack is tiny and not visible without special tests.
Either way, don’t ignore biting pain. A simple adjustment might solve it, but if it’s a crack, early intervention can make the difference between a repair and a more involved treatment.
Roughness, chipping, or a new “edge” you can feel
If your tongue keeps finding a sharp or rough area, that’s often a sign the filling has chipped or the tooth next to it has fractured. Even a small chip can create a plaque trap that increases the risk of decay.
Roughness can also happen when a filling wears down unevenly. Over time, the surface can become pitted, especially with older materials or in patients who grind.
This is one of those signs that’s easy to dismiss because it doesn’t always hurt—but it’s worth fixing before it becomes a bigger structural issue.
Visible cracks, dark lines, or staining around the filling
Not all staining means decay. Composite fillings can stain at the margins from coffee, tea, red wine, or smoking. But a dark line at the edge can also be a sign of leakage or recurrent decay.
Cracks in the tooth near a filling are especially important. Teeth with large fillings are more prone to cracking, and sometimes the crack extends below the gumline.
If you notice a dark shadow under a tooth-colored filling or a change in the tooth’s color, it’s worth getting evaluated. X-rays and an exam can help clarify what’s happening.
Food getting stuck or floss shredding between teeth
If floss starts shredding in one spot, it can indicate a rough margin, overhang, or a chipped edge. Food trapping can also happen when a filling loses its proper contact with the neighboring tooth.
That contact point is important. When it’s open, food packs between teeth and irritates the gum tissue, increasing the risk of gum inflammation and cavities between teeth.
These issues are often fixable, but they shouldn’t be ignored. A small adjustment or replacement can prevent gum problems and new decay.
When it’s not “replace the filling” but “upgrade the restoration”
Sometimes a filling keeps failing because the tooth has outgrown what a filling can reasonably do. If you’ve had the same tooth refilled multiple times, or if the filling is very large, your dentist may recommend a different type of restoration that protects the tooth more effectively.
This can feel like a big step, but it’s often the most conservative long-term move because it prevents future fractures and deeper problems.
When a crown makes more sense than another large filling
A crown covers the tooth like a helmet, protecting weakened cusps (the pointed parts of molars) from cracking. If a tooth has a large filling and the remaining walls are thin, a crown can reduce the chance of a sudden break that turns into an urgent situation.
People often ask, “Do I really need a crown, or can I just do a filling?” The honest answer depends on how much tooth is left, whether there are cracks, and how much force that tooth takes in your bite.
If you’re curious about how crowns work, what the process looks like, and when they’re recommended, you can visit our page for a deeper overview. (And yes—crowns are much more comfortable and natural-looking today than many people expect.)
Inlays and onlays for “in-between” situations
Inlays and onlays sit between a filling and a full crown. They’re often used when damage is too extensive for a simple filling but not so extensive that the whole tooth needs to be covered.
Because they’re typically lab-made, they can fit very precisely and restore strength well. Onlays, in particular, can cover one or more cusps and protect them from fracture.
This option can be ideal for people who want something stronger than a filling while preserving more natural tooth structure than a crown might require.
When cosmetic concerns are part of the decision
Sometimes the filling itself is fine functionally, but the tooth’s appearance becomes the bigger issue—especially with front teeth. You might have bonding that keeps staining, a filling that’s visible when you smile, or edges that chip repeatedly.
In those cases, a cosmetic upgrade can be both aesthetic and practical. For example, veneers can cover discoloration, reshape teeth, and create a more consistent look—while also protecting the outer surface.
If you’ve been exploring cosmetic options that preserve more natural enamel, minimal prep veneers are one approach that may be worth learning about, depending on your bite and goals.
What happens during a filling replacement (and why it’s usually straightforward)
The idea of “redoing” dental work can sound stressful, but replacing a filling is often simpler than the original cavity treatment—especially if the issue is caught early and the decay hasn’t spread deep.
Knowing what to expect can take a lot of the anxiety out of the appointment.
Assessment: checking the margins, bite, and decay risk
First, your dentist will look at the filling’s edges, check for cracks, and evaluate symptoms. X-rays are commonly used to see if there’s decay underneath or between teeth. If biting pain is involved, they may do special tests to check for cracks or nerve inflammation.
They’ll also check your bite. A filling that’s slightly too high can cause pain and may not need full replacement—sometimes it just needs to be adjusted and polished.
This assessment step matters because it determines whether you need a simple replacement, a different type of restoration, or treatment for the nerve.
Removing the old filling and any decay
If replacement is needed, the dentist will numb the area, remove the old filling material, and clean out any decay. If the tooth is healthy underneath, that’s great—replacement can be quick.
If there’s deeper decay than expected, your dentist may recommend additional steps, like a protective liner or (in more advanced cases) root canal therapy. This isn’t common for routine replacements, but it can happen when decay has been silently progressing.
Once the tooth is cleaned and shaped, the new filling is placed, shaped, and polished so it feels natural when you bite.
Aftercare: what’s normal and what’s not
Mild sensitivity for a few days can be normal, especially to cold. Your tooth has been worked on, and the nerve can be temporarily irritated. Using a toothpaste for sensitive teeth and avoiding extreme temperatures for a short time can help.
What’s not normal is intense pain, swelling, or sensitivity that worsens after the first week. Those symptoms should be checked promptly.
It’s also normal to need a bite adjustment. If the filling feels “tall” or you hit it first when chewing, call your dentist—an adjustment can be quick and can prevent future problems.
How to make your fillings last longer in real life
You can’t control everything (like genetics or how your teeth are shaped), but you can absolutely stack the odds in your favor. The best strategies are simple, consistent habits—not complicated routines.
Think of this section as “filling insurance” you can do at home.
Brush and floss like you’re protecting the margins (because you are)
Fillings often fail at the edges, so your daily goal is to keep plaque from sitting along those margins. Brush twice a day with fluoride toothpaste, and focus on the gumline and the areas where teeth meet.
Flossing matters even more when you have fillings between teeth, because recurrent decay often starts where your toothbrush can’t reach. If floss is tough for you, try floss picks, interdental brushes, or a water flosser—whatever you’ll actually use consistently.
If you’re cavity-prone, ask your dentist about prescription fluoride toothpaste or fluoride varnish. Extra fluoride can slow down or stop early decay before it becomes a filling replacement.
Reduce frequent sugar and acid exposure (frequency beats quantity)
It’s not just how much sugar you eat—it’s how often. Every time you snack on something sugary or sip something acidic, your mouth shifts into an “acid attack” phase that can last 20–40 minutes or more.
If you’re constantly grazing, your teeth don’t get much recovery time. Try to keep snacks to set times, drink water between meals, and avoid slowly sipping sweetened coffee or soda over hours.
Chewing sugar-free gum with xylitol after meals can help stimulate saliva, which naturally buffers acids and supports remineralization.
Protect your teeth if you grind or play sports
If you grind at night, a custom night guard can protect both fillings and tooth enamel. Over time, grinding can cause microcracks that lead to broken fillings or fractured teeth.
If you play contact sports, a mouthguard is a must. A hard hit can chip teeth or pop out fillings instantly, even if everything felt fine beforehand.
These protective tools are often cheaper than repeated dental repairs—and they help prevent the kind of sudden tooth damage that becomes urgent and painful.
When a filling problem becomes urgent (and what to do next)
Some filling issues can wait a week or two for a normal appointment. Others shouldn’t wait. Knowing the difference can save you from a long night of pain—or from turning a fixable problem into a bigger one.
If you’re unsure, it’s always okay to call a dental office and describe your symptoms. They can help you decide how quickly you need to be seen.
Red flags that deserve prompt attention
Seek care quickly if you have swelling, a pimple-like bump on the gum, fever, or worsening pain that doesn’t respond to over-the-counter medication. Those can be signs of infection.
Also treat a cracked tooth seriously, especially if a piece breaks off and you’re left with a sharp edge or exposed dentin. The tooth can become very sensitive, and the crack can spread with chewing.
If a filling falls out completely, the tooth may be vulnerable to further fracture or rapid decay. Even if it doesn’t hurt, it’s best to get it restored soon.
What “temporary fixes” help (and what to avoid)
If you lose a filling, over-the-counter temporary dental repair kits can help cover the area for a short time. They’re not a substitute for treatment, but they can reduce sensitivity and protect the tooth until you’re seen.
Avoid chewing on that side, and skip sticky or very hard foods. If the area is sharp, dental wax (often sold for braces) can prevent it from cutting your cheek or tongue.
Try not to self-medicate by placing aspirin directly on the gum or tooth—it can cause a chemical burn. If pain control is needed, follow label directions for common OTC pain relievers unless your physician has advised otherwise.
Getting help fast when you need it
When pain is intense or a tooth breaks unexpectedly, you don’t want to wait and hope it improves. That’s when emergency dental care can make a big difference—whether you need a quick evaluation, a temporary stabilization, or same-day treatment to stop the pain.
Even if the final restoration (like a crown) happens later, urgent care can protect the tooth and keep the situation from spiraling.
The main takeaway: if your symptoms feel “bigger than a normal toothache,” trust that instinct and get checked.
Common questions people have about filling replacement
Fillings are so common that it’s easy to assume everyone knows what to expect—but most people still have the same practical questions. Here are a few that come up all the time, with real-world answers.
If you’re trying to decide whether to book an appointment, these can help you gauge what’s normal and what’s worth checking.
Does replacing a filling hurt more than getting the first one?
Usually, no. Many replacements are similar to the original experience, and sometimes easier if the cavity is small and the tooth isn’t sensitive. Local anesthetic keeps things comfortable.
Where it can feel more intense is when the decay is deeper, the tooth is cracked, or the nerve is already irritated. In those cases, the tooth may be more sensitive, and your dentist may take extra steps to keep you comfortable.
If dental anxiety is part of the equation, tell your dentist. Small changes—like more numbing time, breaks, or calming techniques—can make a big difference.
Can a filling be repaired instead of replaced?
Sometimes. If a small piece chips or a margin is slightly rough, your dentist may be able to smooth, polish, or add material to repair it. This depends on the type of filling, the location, and whether there’s decay.
If there’s recurrent decay, replacement is usually the better option because the decay needs to be removed and the seal restored. If the filling is old and the tooth is weakened, upgrading to an onlay or crown may be the most protective choice.
The best approach is individualized: the “right” fix is the one that keeps the tooth healthy and stable for the longest time.
How do dentists know if decay is under an old filling?
They use a combination of visual exam, tactile checks (gently exploring margins), and X-rays. Bitewing X-rays are especially useful for spotting decay between teeth and under restorations.
Sometimes decay is obvious, and sometimes it’s subtle—especially in early stages. That’s why comparing current X-rays to older ones can be helpful, since changes over time can reveal a developing problem.
If you have symptoms but nothing shows clearly, your dentist may monitor the tooth, adjust the bite, or recommend additional imaging or tests.
How long should you wait before checking a suspicious filling?
If you have a mild, new sensitivity that’s not getting worse, it’s reasonable to schedule a normal appointment soon—especially if it’s been a while since your last exam. If you can point to one tooth and say, “Something feels different here,” that’s enough reason to have it evaluated.
If you have pain when biting, a visible crack, a missing chunk of filling, swelling, or pain that wakes you up at night, don’t wait. Those are the scenarios where quick care can protect the tooth and prevent complications.
Most importantly: fillings don’t fail on a neat timeline. Some last decades; others need attention sooner. The best plan is to keep up with regular dental visits so small issues are caught early—while the fix is still simple.