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Something to Smile About

Find out how braces help keep your teeth healthy

January 16, 2023

By Andrew Klein

AS YOU READ, THINK ABOUT why it’s important for a person’s teeth to be correctly aligned.

If you have braces, you’re not alone. About 5 million Americans wear these dental devices—and about 70 percent of them are kids or teens. Braces correct problems that occur when teeth are out of place. The idea isn’t new: Dentists have been using braces to straighten teeth for the past 200 years!

The most common type of braces consists of metal brackets glued to teeth. These brackets are connected by a curved wire often made of nickel titanium. This alloy, or metal mixture, is flexible, so the wire can be bent to attach to each bracket. The alloy also reacts to the heat of a person’s mouth, causing the wire to slowly return to its original shape. This movement puts pressure on the teeth, gradually changing their position and that of the underlying jawbones they’re attached to. “The teeth are like a house and the bones are the foundation,” explains Dr. Brent Larson. He’s an orthodontist—a dentist who specializes in aligning teeth—and professor at the University of Minnesota. “To have a nice straight house, you need a good foundation underneath.”

When a person’s top and bottom sets of teeth don’t fit together, the teeth can wear down and lose enamel. Without this hard, protective outer layer, a person can develop tooth decay. Crooked or overlapping teeth can also be hard to brush and floss, which can lead to cavities and gum disease. That’s why braces aren’t just cosmetic. “The goal of having braces is to end up with a beautiful, healthy smile,” says Larson.

If you have braces, you’re not alone. About 5 million Americans wear these dental devices. And about 70 percent of them are kids or teens. When teeth are out of place, problems occur. Braces correct these problems. The idea isn’t new. Dentists have used braces to straighten teeth for 200 years!

Dentists can glue metal brackets to teeth. That’s the most common type of braces. A curved wire connects these brackets. The wire is often made of an alloy of nickel titanium. This metal mixture is flexible, so the wire can be bent to attach to each bracket. The alloy also reacts to the heat of a person’s mouth. That makes the wire slowly return to its original shape. This movement puts pressure on the teeth. Over time, it changes their position. It also changes the position of the jawbones connected to the teeth. “The teeth are like a house and the bones are the foundation,” explains Dr. Brent Larson, a professor at the University of Minnesota. He’s an orthodontist—a dentist who corrects the position of teeth. “To have a nice straight house, you need a good foundation underneath.”

Sometimes, a person’s top and bottom teeth don’t fit together. Then the teeth can wear down and lose enamel. This hard outer layer protects teeth. Without it, a person can develop tooth decay. Crooked or overlapping teeth can also be hard to brush and floss. That can lead to cavities and gum disease. So braces don’t just improve looks. “The goal of having braces is to end up with a beautiful, healthy smile,” says Larson.

Brackets

Small metal squares are glued to the surface of each tooth. They’re connected by a wire that runs through each bracket.

Arch Wire

The pulling force of tension in the arch wire puts pressure on the teeth, causing them to shift. As this happens, the wire loosens. Patients have the wire replaced or tightened every four to six weeks to ensure pressure is continually applied to teeth.

Ligatures

Elastic bands, which come in a variety of fun colors, wrap around each bracket to secure the arch wire in place.

Brackets

Small metal squares are glued to the surface of each tooth. They’re connected by a wire that runs through each bracket.

Arch Wire

Ligatures

Elastic bands, which come in a variety of fun colors, wrap around each bracket to secure the arch wire in place.

Mouth Remodeling

Teeth are anchored into a person’s underlying jawbone. As braces shift teeth, the jawbone around each tooth breaks down and then reforms to hold it in its new position. Here’s how it works.

Braces shift teeth, which applies pressure to the surrounding tissues.

The pressure causes osteoclast cells to release acids and proteins near the roots of shifting teeth. The substances break down the jawbone.

Osteoblast cells deposit minerals to rebuild the jawbone around teeth.

Mouth Remodeling

Teeth are anchored into a person’s underlying jawbone. As braces shift teeth, the jawbone around each tooth breaks down and then reforms to hold it in its new position. Here’s how it works.

Braces shift teeth, which applies pressure to the surrounding tissues.

The pressure causes osteoclast cells to release acids and proteins near the roots of shifting teeth. The substances break down the jawbone.

Osteoblast cells deposit minerals to rebuild the jawbone around teeth.

The Evolution of Braces

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2,500 B.C.

Egyptian mummies have been found with metal bands wrapped around their teeth. It’s unclear today whether the appliances were installed before or after death.

2,500 B.C.

Egyptian mummies have been found with metal bands wrapped around their teeth. It’s unclear today whether the appliances were installed before or after death.

1st Century A.D.

An ancient Roman medical writer named Aulus Cornelius Celsus documents attempts to shift teeth by applying pressure by hand at regular intervals.

1st Century A.D.

An ancient Roman medical writer named Aulus Cornelius Celsus documents attempts to shift teeth by applying pressure by hand at regular intervals.

SCIENCE SOURCE

1819

French dentist Christophe-François Delabarre invents the precursor to modern braces—a wire cage that fits over a row of teeth.

1819

French dentist Christophe-François Delabarre invents the precursor to modern braces—a wire cage that fits over a row of teeth.

ALAMY STOCK PHOTO

1900s

The term braces becomes widely used. Metal bands, often made of gold or silver, were wrapped around each tooth and wired together.

1900s

The term braces becomes widely used. Metal bands, often made of gold or silver, were wrapped around each tooth and wired together.

SPACEX

1979

Nickel titanium alloy, created by NASA for future applications in space, is used to make wires for braces.

1979

Nickel titanium alloy, created by NASA for future applications in space, is used to make wires for braces.

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1997

Invisalign aligners are invented as an alternative to braces. These clear plastic aligners slip over a person’s teeth to shift their position.

1997

Invisalign aligners are invented as an alternative to braces. These clear plastic aligners slip over a person’s teeth to shift their position.

The Evolution of Braces

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2,500 B.C.

Egyptian mummies have been found with metal bands wrapped around their teeth. It’s unclear today whether the appliances were installed before or after death.

2,500 B.C.

Egyptian mummies have been found with metal bands wrapped around their teeth. It’s unclear today whether the appliances were installed before or after death.