Filling Options for Cavities

Key Takeaway: When you have a cavity, your dentist removes decayed tooth structure and restores it with filling material. Learning more about Cost of Tooth Decay Prevention can help you understand this...

When you have a cavity, your dentist removes decayed tooth structure and restores it with filling material. Learning more about Cost of Tooth Decay Prevention can help you understand this better. You have choices: amalgam (silver), composite (tooth-colored), glass ionomer, or sometimes more complex options. Each has different costs, longevity, and appearance implications.

Cavity size determines complexity. Small cavities affecting one tooth surface are straightforward. Large cavities affecting multiple surfaces or requiring root canal treatment are complex and expensive. Location matters too—front teeth need aesthetic composite; back teeth might use amalgam or composite.

Amalgam Fillings: Durable and Affordable

Amalgam (mercury-silver alloy) fillings cost $150 to $300 per filling. A simple one-surface cavity costs toward lower end; large multi-surface cavities cost more. Amalgam is extremely durable, lasting 10 to 30 years. For large back-tooth cavities, amalgam is still unsurpassed for longevity and value.

The downside: amalgam is silver-colored and conspicuous on front teeth. Many patients don't want visible silver fillings for esthetic reasons. Amalgam also requires removal of slightly more tooth structure than composite. Some patients avoid amalgam due to mercury concerns (though scientific evidence supports safety at dental doses).

Tooth-colored composite fillings cost $200 to $600 per filling. They're tooth-colored, making them invisible cosmetically. Composite bonds to tooth structure, requiring slightly less tooth removal than amalgam. Composite works on front or back teeth.

The downside: composite lasts 5 to 10 years typically—shorter than amalgam. Composite can stain, chip, or fracture. You'll likely replace composite fillings multiple times over a lifetime. For small cosmetic cavities, composite's appearance benefit justifies the cost. For large back-tooth cavities, amalgam's superior longevity might be more cost-effective long-term.

Glass Ionomer: Moderate Option

Glass ionomer (tooth-colored, fluoride-releasing) costs $200 to $400 per filling. It releases fluoride, providing additional cavity protection. Glass ionomer bonds to tooth without etching enamel. It's less technique-sensitive than composite.

The downside: glass ionomer is less durable than composite or amalgam, lasting 5 to 7 years. It wears faster and stains more readily. Glass ionomer works for temporary restorations or situations where fluoride release is beneficial, but it's falling out of favor as composite improves.

Large Cavity Restoration: When Fillings Fail

When cavities are very large (affecting multiple tooth surfaces, more than half the tooth), simple fillings fail. These cavities need onlay (partial coverage) or crown (full coverage) restorations. An onlay costs $800 to $1,500. A crown costs $800 to $2,500.

Onlays and crowns require laboratory fabrication (1 to 2 weeks) and tooth preparation. They last substantially longer than fillings—10 to 15 years for crowns, providing superior longevity and strength for large cavities. For large cavities, investing in a crown now prevents extraction and implant costs ($4,000 to $8,000) later.

Root Canal Treatment: When Pulp is Involved

If decay reaches the nerve (pulp), you need root canal treatment. This costs $800 to $1,200 plus restoration. The tooth is then fragile and usually needs a crown ($800 to $2,000) for stability. Total cost: $1,600 to $3,200.

Preventing decay before it reaches the nerve is infinitely cheaper. Treating small cavities with simple fillings ($200 to $600) prevents progression to root canal and crown ($1,600 to $3,200). This underscores the value of prompt cavity treatment.

Cost-Effectiveness Over Time

Small one-surface cavity on back tooth:

  • Amalgam: $200 initially, potentially lasts 20 years = $200 total
  • Composite: $300 initially, replace every 7 years = $900 over 21 years

Large three-surface cavity on back tooth:
  • Amalgam: $400 initially, lasts 15-20 years = $400 to $600 total
  • Composite: $500 initially, replace every 7 years = $1,500 over 21 years
  • Crown: $1,500 initially, lasts 15 years = $1,500 total
Front tooth cavity (cosmetic is important):
  • Composite: $400 initially, replace every 7 years = $1,200 over 21 years
  • Veneer: $1,200 initially, lasts 12-15 years = $2,400 over 30 years

Tooth Preparation and Pain

Cavity removal is painless with local anesthesia. Your dentist numbs the tooth and surrounding area with injection. Once numb, you feel no pain—only pressure and vibration from the drill. The process takes 15 to 45 minutes depending on cavity size. Learn more about preventing cavities.

Replacement and Repair Costs

Composite fillings often need repair or replacement before they fail completely. Repair costs $75 to $150. Replacement costs $200 to $600. Over a lifetime, composite filling repairs accumulate. Amalgam rarely needs repair—it lasts or fails completely.

A cracked or failed filling requires immediate replacement to prevent further decay. Delaying replacement risks expanding cavity and potential root canal need. Address any loose or cracked restorations promptly.

Making Your Restoration Last

Once you've invested in a dental restoration, protect it to get the longest possible lifespan. Avoid chewing ice, hard candy, or other extremely hard foods that can crack fillings and crowns. If you grind your teeth at night, ask your dentist about a night guard—grinding can reduce filling lifespan by half.

Brush and floss carefully around restorations to prevent new decay at the margins where filling meets tooth. Attend regular dental checkups so your dentist can spot small problems like worn or cracked fillings before they become big problems requiring crowns or root canals. A $50 dental visit that catches a failing filling early can save you $1,000 or more in emergency treatment later.

For more information, see Bite Force and Teeth: Complete Guide.

Conclusion

For small cosmetic cavities: composite fillings ($200-$600) provide invisible restoration for 5 to 10 years.

For small functional cavities: amalgam ($150-$300) lasts 15 to 30 years with superior durability.

For large cavities: crowns ($800-$2,000) provide superior longevity and strength compared to fillings.

For cavities approaching nerve: prompt treatment prevents root canal ($800-$1,200) and crown costs.

> Key Takeaway: When you have a cavity, your dentist removes decayed tooth structure and restores it with filling material.