Crown vs Filling: What Is the Difference?
A filling replaces a small section of tooth lost to decay. The dentist removes the cavity, then packs the space with a filling material such as composite resin or amalgam. The rest of the tooth stays intact and continues to support the filling.
A crown replaces the entire outer shell of the tooth above the gum line. The dentist reshapes what remains of the tooth into a smaller core, then cements a custom-made cap over it. The crown becomes the new outer surface of the tooth, protecting the weakened structure underneath.
When a Filling Is Enough
A filling is the right choice when the cavity is small to moderate and most of the natural tooth is still healthy. The tooth must have enough remaining wall structure to hold the filling in place and withstand normal chewing forces.
- The cavity affects less than one-third of the tooth surface
- No cusps (the raised points on a back tooth) are missing or cracked
- The tooth has not had a root canal
- The tooth is not under heavy biting force, such as a molar in someone who grinds their teeth
When a Crown Is Needed
A crown is recommended when the tooth has lost too much structure for a filling to hold. Without full coverage, the remaining walls of the tooth can flex under chewing pressure and crack.
- More than half the tooth structure is damaged or missing
- One or more cusps are broken or weakened
- The tooth has had root canal treatment, which removes the blood supply and makes it more brittle
- A large existing filling has failed, leaving even less tooth to work with
- The tooth has a vertical crack that a filling cannot stabilize
How Your Dentist Decides: Crown or Filling
The decision between a crown and a filling comes down to structural risk. Your dentist evaluates how much tooth is left, where the damage is, and what forces the tooth will face over the next 10 to 20 years.
Teeth in the back of the mouth absorb far more chewing force than front teeth. A moderate cavity on a front tooth may do fine with a filling, while the same amount of damage on a molar may call for a crown. Your bite pattern matters too. People who grind or clench their teeth put significantly more stress on restorations.
Tooth Location and Bite Force
Molars handle the heaviest chewing forces. A large filling on a molar is more likely to fail than the same filling on a premolar or front tooth. Dentists factor in the tooth's position when recommending a crown vs a filling.
Front teeth generally handle fillings well because they experience shearing forces rather than heavy compression. However, front teeth with significant cosmetic damage may benefit from a crown for appearance and durability.
Previous Restorations and Repeat Repairs
Each time a filling is replaced, the dentist removes a small amount of additional tooth structure. After two or three rounds of filling replacement, the remaining tooth may be too thin to support another filling. At that point, a crown protects the tooth from splitting.
If you have a tooth with a large filling that keeps breaking, your dentist may recommend upgrading to a crown rather than placing another filling that is likely to fail again.
Cost Comparison: Crowns vs Fillings
Fillings cost significantly less upfront than crowns. However, the long-term cost depends on how many times a filling needs to be replaced over the life of the tooth.
Filling Costs
A composite (tooth-colored) filling typically costs $150 to $400 per tooth, depending on the size of the cavity and where you live. Amalgam (silver) fillings are slightly less expensive but are used less frequently today. Most dental insurance plans cover fillings at 70% to 80% after the deductible. Costs vary by location and provider.
Crown Costs
A dental crown typically costs $800 to $1,500 per tooth. Porcelain, ceramic, and zirconia crowns tend to cost more than metal or porcelain-fused-to-metal options. Most dental insurance plans cover crowns at 50% after the deductible, classifying them as a major procedure. Costs vary by location, provider, and the material used.
While a crown costs more upfront, it may be the less expensive option over time if the alternative is replacing a large filling every few years.
How Long Do Crowns and Fillings Last?
Longevity depends on the material, the tooth's location, your oral hygiene, and habits like grinding or clenching.
Filling Lifespan
Composite fillings typically last 5 to 10 years. Amalgam fillings can last 10 to 15 years or longer. Small fillings in low-stress areas often exceed these averages. Large fillings on molars tend to fall at the shorter end of the range.
Fillings can fail by cracking, wearing down, or developing new decay around the edges. Regular dental checkups catch these problems before the tooth cracks or infection develops.
Crown Lifespan
Dental crowns typically last 10 to 15 years, and many last 20 years or more with good oral hygiene. Zirconia and gold crowns tend to be the most durable. Porcelain crowns on front teeth can chip if you bite into hard objects.
A crown can fail if decay develops at the margin where the crown meets the natural tooth, if the cement washes out, or if the tooth underneath fractures. Wearing a night guard can extend the life of a crown significantly if you grind your teeth.
What Happens When a Filling Fails
A failed filling does not always mean you need a crown, but it often points in that direction. When a filling cracks, falls out, or develops decay around it, the dentist must remove the old filling and the new decay. This leaves less tooth structure than before.
If enough tooth remains, a new, larger filling may work. If the walls are thin or a cusp is compromised, a crown is the safer option. Placing a filling in a tooth that really needs a crown can lead to a fracture that makes the tooth unsaveable.
Signs that a filling may be failing include sensitivity to hot or cold, a rough or sharp edge you can feel with your tongue, visible cracks around the filling, or a dark line at the edge of a tooth-colored filling.
Pros and Cons of Crowns vs Fillings
Both crowns and fillings have clear strengths and limitations. The best option depends on your specific situation, not on one being universally better than the other.
Fillings: Pros and Cons
Fillings preserve more natural tooth structure, cost less, and require only one appointment. They work well for small to moderate cavities. However, fillings have limits. They cannot protect a weakened tooth from cracking, they wear out faster than crowns, and large fillings on molars are more likely to fail.
Crowns: Pros and Cons
Crowns provide full coverage protection, last longer than fillings, and can restore both strength and appearance. They are the standard of care after root canal treatment on back teeth. However, crowns require removing more tooth structure during preparation, cost more, and typically need two appointments (unless your dentist uses same-day CAD/CAM technology).
Getting a Second Opinion on a Crown
If your dentist recommends a crown and you are not sure it is necessary, getting a second opinion is a reasonable step. This is especially true if the tooth does not hurt, the current filling seems fine, or the cost is a concern.
A prosthodontist is a dental specialist trained specifically in restoring damaged teeth. They can evaluate whether a crown is truly needed or if a more conservative option would work. Prosthodontists complete 3 years of additional residency training beyond dental school, focused on crowns, bridges, dentures, and complex restorations.
When seeking a second opinion, ask the new dentist to explain what they see on the X-ray and what risks you face with each option. A good clinician will explain the trade-offs clearly and let you decide.
When to See a Prosthodontist
Most crowns and fillings are placed by general dentists. However, a prosthodontist can be especially helpful in certain situations.
Consider seeing a prosthodontist if you need crowns on multiple teeth, if a previous crown has failed, if you have complex bite issues, or if you want to discuss options for a tooth that other dentists have said cannot be saved. Prosthodontists are also the specialists to see when you need a combination of crowns, bridges, or implants to restore your smile.
Find a Prosthodontist Near You
Every prosthodontist on My Specialty Dentist has verified specialty credentials. Search by location to find prosthodontists in your area, compare their experience, and schedule a consultation.
Search Prosthodontists in Your Area