The short version: tooth-colored (composite) fillings are the standard choice today for most cavities because they blend with the tooth, preserve more tooth structure, and bond directly to enamel and dentin. Silver (amalgam) fillings, the traditional option that has been used for well over a century, are still durable and safe, but are used much less often now, mostly on back teeth or in specific clinical situations.
Dr. Zack Finnegan, DMD at Magnolia Smiles in Woodstock, GA places tooth-colored fillings for almost all new restorations. This guide covers the honest differences, why the modern preference has shifted, and when replacing older silver fillings makes sense.
What each material actually is
Silver (amalgam) fillings
A mix of silver, tin, copper, and mercury. Compressed into the tooth after the decay is removed. Strong, durable, and inexpensive. Been in use for more than 150 years.
Tooth-colored (composite) fillings
A blend of resin and fine glass or ceramic particles. Applied to the tooth in layers, sculpted to shape, and hardened with a light. Bonds directly to the tooth.
Both materials repair decayed or damaged teeth. They just do it in different ways.
Head-to-head comparison
Appearance
- Composite: matches the natural color of the tooth. Nearly invisible.
- Amalgam: silver-gray. Visible in the mouth, especially on lower teeth or when laughing.
Bond to the tooth
- Composite: bonds chemically to enamel and dentin. Reinforces the tooth.
- Amalgam: held in mechanically by the shape of the preparation. Does not bond.
Tooth preservation
- Composite: can be placed in smaller preparations because it bonds. More natural tooth structure preserved.
- Amalgam: requires more tooth structure to be removed to create a mechanical lock.
Durability
- Composite: modern composites last 7 to 15 years or longer in appropriate placements. Not ideal for very large restorations or heavy grinders.
- Amalgam: commonly lasts 10 to 20 years or longer, especially in large back-tooth restorations under heavy chewing force.
Sensitivity
- Both can cause short-term sensitivity after placement. Composite sensitivity usually resolves within a few weeks.
Repair
- Composite: can often be repaired or added to.
- Amalgam: typically requires full replacement if it fails.
Cost
- Composite: slightly higher per filling.
- Amalgam: less expensive per filling.
Insurance
- Most dental plans cover composite fillings at the same rate as amalgam. A minority still pay less for composite on back teeth. The office verifies this before treatment.
Are silver fillings dangerous?
The mercury in amalgam is bound with other metals into a stable alloy. Regulatory bodies (FDA, WHO, ADA) consider amalgam safe for most patients. The current guidance is:
- Do not remove amalgam fillings just for mercury concerns if the fillings are intact.
- Certain populations (pregnant patients, children under six, patients with certain kidney conditions) should discuss placement of new amalgam with their dentist. New amalgam is uncommon anyway.
- Improper removal (drilling without proper isolation and air filtration) exposes patients and staff to mercury vapor briefly. A modern removal protocol handles this safely.
When to replace an old silver filling
Replacement is not automatic. It is a decision based on the tooth, not the material.
Replace when:
- The tooth around the filling is cracked or broken.
- New decay is visible at the margin.
- The filling has fractured, chipped, or fallen out.
- The tooth is sensitive in a way that points to a leaking filling.
- The tooth has grown darker, suggesting stain from the amalgam has crept in.
- A tooth is aesthetically important to you (a visible tooth in your smile) and you prefer tooth-colored.
Leave alone when:
- The filling and surrounding tooth are stable.
- There is no decay at the margin.
- The tooth is asymptomatic.
- You are comfortable with how it looks.
Removing a sound amalgam just because it is old often means unnecessary drilling and slightly weaker tooth structure afterward. Learn more about replacing old silver fillings in Woodstock, GA if you have specific concerns.
What Magnolia Smiles does
- Places tooth-colored composite for essentially all new fillings.
- Reviews existing silver fillings at each recall for margin integrity and cracks in the tooth.
- Recommends replacement only when clinically indicated.
- When replacement is needed, uses proper isolation and air-clearance techniques.
Learn more about restorative dentistry at Magnolia Smiles.
Frequently asked questions
Should I replace all my old silver fillings?
No. Replace only what is failing or where the tooth around the filling shows problems.
Do composite fillings cost more than silver?
Slightly, per filling. Most dental plans cover composite fillings.
Do composite fillings last as long as silver?
In appropriate placements, yes. Very large restorations under heavy grinding may do better as a crown than as either material.
Are silver fillings still used?
Rarely, and mostly for large back-tooth restorations in specific situations.
How long does it take to place a composite filling?
Usually 30 to 60 minutes per tooth. Multiple fillings can often be done in one appointment.
Will a composite filling stain?
Composite can pick up some surface stain over years, especially at the margin. Cleanings help. Older, discolored fillings can be replaced.
Ready to review your fillings?
If you are unsure whether an old filling should be replaced or left alone, a short exam gives you a clear answer. Contact Magnolia Smiles to book.
Reviewed by Dr. Zack Finnegan, DMD. Magnolia Smiles, Woodstock, GA. This article is for general education and does not replace an in-person exam.