Some say the eyes are the window to the soul. But if you really want to know what someone’s about, check their smile. A welcoming show of pearly whites makes a great first impression, while a tight-lipped smile or whiff of bad breath does the opposite.

Read on for tips on how to make sure you’re giving your teeth the care they deserve.

Brush your teeth for two minutes, twice a day, says the American Dental Association (ADA). This will keep your teeth in top form. Brushing your teeth and tongue with a soft-bristled toothbrush and fluoride toothpaste cleans food and bacteria from your mouth. Brushing also washes out particles that eat away at your teeth and cause cavities.

The mouth is 98.6ºF (37ºC). Warm and wet, it’s filled with food particles and bacteria. These lead to deposits called plaque. When it builds up, it calcifies, or hardens, on your teeth to form tartar, also called calculus. Not only does tartar irritate your gums, it can lead to gum disease as well as cause bad breath.

Be sure to brush in the morning to help get rid of the plaque that’s built up overnight.

If you brush more than twice a day, for longer than four minutes total, you could wear down the enamel layer that protects your teeth.

When tooth enamel isn’t there, it exposes a layer of dentin. Dentin has tiny holes that lead to nerve endings. When these are triggered, you might feel all sorts of pain. According to the Centers for Disease Control and Prevention, almost 20 percent of American adults have experienced pain and sensitivity in their teeth.

It’s also possible to brush too hard. Brush your teeth like you’re polishing an eggshell. If your toothbrush looks like someone sat on it, you’re applying too much pressure.

Enamel is strong enough to protect teeth from everything that goes on inside your mouth, from eating and drinking to beginning the digestive process. Children and teens have softer enamel than adults, leaving their teeth more prone to cavities and erosion from food and drink.

Want to avoid minimal scraping at your next checkup? Flossing loosens the particles that brushing misses. It also removes plaque, and in so doing prevents the buildup of tartar. While it’s easy to brush plaque away, you need a dentist to remove tartar.

You finally have an answer to the age-old question: “Which comes first, flossing or brushing?” It doesn’t matter, according to the ADA, as long as you do it every day.

Sip All Day, Get Decay” is a campaign from the Minnesota Dental Association to warn people of the dangers of soft drinks. It’s not just sugar soda, but diet soda, too, that harms teeth. The acid in soda attacks teeth. Once acid eats away at enamel, it goes on to create cavities, leaves stains on the tooth surface, and erodes the inside structure of the tooth. To avoid drinking-related tooth decay, limit soft drinks and take good care of your teeth.