Tooth-colored vs silver fillings: which should you choose?

The short answer: composite looks better, amalgam can be tougher

Composite fillings are tooth-colored and bond to your tooth, so they blend in and need less drilling. Amalgam fillings are silver, very durable and usually cost less. For most people, composite is the better choice for teeth that show. For big fillings on back teeth, either one can work.

The right pick depends on the size and spot of the cavity, your budget and how much you care about looks.

Cavities do not heal by themselves, so the real question is not whether to fill the tooth but when and with what. The earlier a cavity is found, the smaller the filling and the better the choices.

What each filling is made of

Composite resin is a mix of plastic and fine glass particles. Your dentist places it in layers and hardens each layer with a blue light. It is matched to the color of your tooth.

Amalgam is a mix of metals, including silver, tin, copper and mercury. It has been used for over a century. It is soft when placed and hardens quickly in the tooth.

There are also other filling materials, such as gold and porcelain. They are used less often for simple cavities, and they are usually made in a lab and placed at a second visit. Your dentist can explain when they make sense.

How they compare

Here is a quick look at the main differences:

Insurance can change the math. Some plans pay for amalgam fully but pay only part of the cost of composite. Ask your plan before the visit, so you know your share.

• Looks: composite blends in, amalgam is silver and visible
• Strength: amalgam handles heavy chewing well, composite is good for small and medium repairs
• Tooth removal: composite bonds, so it usually needs less healthy tooth removed
• Time: composite takes longer, because the tooth must stay dry and each layer is hardened
• Cost: composite usually costs more, and some plans cover less of it
• Repairs: composite can often be fixed or added to with a small touch-up

How long they last, and the downsides

The American Dental Association's MouthHealthy site says composites give good durability and resist fracture in small to mid-size fillings. It also says some studies show composite fillings can be less durable and need replacing sooner than amalgam.

Estimates of how long they last vary. Different sources put composite fillings at roughly 5 to 10 years or more, and amalgam fillings at up to 15 years. Your habits matter as much as the material. Grinding your teeth, a sugary diet and skipping checkups shorten the life of any filling.

To get the most from any filling, treat the cause of the cavity as well as the cavity itself. Cut back on sipping sugary or acidic drinks through the day, brush with a fluoride toothpaste twice a day and floss. The ADA's MouthHealthy site says the best filling is no filling, which is why prevention matters.

Between visits, pay attention to how a new filling feels. A high spot can make the tooth sore when you bite, and it is a quick fix at the dentist. Do not wait for it to wear down by itself.

A few. They cost more, and the placement takes longer. In a big cavity on a back tooth, they may wear faster or can leak at the edge, which can lead to new decay under the filling.

Some people feel more sensitivity to hot and cold in the first days, especially with a deep filling. That usually settles in a few weeks. Tell your dentist if it does not, or if it gets worse.

Is amalgam safe? What about mercury?

This is a common worry. Amalgam does contain mercury, but once it is mixed with the other metals it is locked in the filling. The ADA has reviewed the evidence and considers amalgam safe for most people.

If you are pregnant, have a health condition or a known sensitivity to metals, talk with your dentist about your options. If you are concerned, ask for composite instead. It is your choice.

Many dentists now place far more composite than amalgam, mostly because patients prefer the look and because composite bonds to the tooth. That is a preference and a trend, not a finding that silver fillings are unsafe.

Which one is right for which tooth?

There is no single answer, but here are common guidelines:

Ask your dentist why they recommend a material. A good reason sounds like "this cavity is large and on a chewing surface," or "this tooth shows when you smile." Those are reasons you can weigh.

• Front teeth and visible spots: composite
• Small to medium cavities on back teeth: composite is a good choice
• Very large cavities on back teeth: your dentist may suggest an inlay, onlay or crown instead
• Hard-to-keep-dry spots, such as under the gum line: other materials may work better
• If you grind your teeth: ask about a night guard to protect any filling

Replacing old silver fillings

You do not need to replace a silver filling just because it is old or because of the look. If it is not cracked, leaking or decayed underneath, it may be better left alone. Each time a filling is replaced, a bit more of the tooth is removed.

Your dentist will check old fillings at your exams, using X-rays to see underneath them. Replace one only if there is a reason, such as a crack, a leak or new decay.

If you do choose to replace a silver filling, your dentist will use methods that limit the dust and vapor. Ask about the steps they take. Replacing fillings is a personal choice, and a good dentist will respect it while giving you honest advice about the tooth.

Tooth-colored fillings at KDA

At Kendall Dental Associates, we offer esthetic, tooth-colored fillings, plus porcelain inlays and onlays and crowns for bigger repairs. We use digital X-rays to find cavities early, when a small filling is enough.

If you have a sore tooth, a broken filling or a silver filling you are unsure about, call 305-271-1421 or come in at 8833 SW 107th Ave, Miami, in the Kendall Mall. Our hours are Monday to Friday, 8:00 AM to 5:00 PM, and emergency care is available 24/7. We accept most dental insurances and most Medicare supplemental plans, and financing is available.

Common questions

This article is general information, not medical advice. Your dentist will confirm what is right for you at your exam. General information checked against: mouthhealthy.org, mouthhealthy.org, ada.org.