What is tooth enamel?

Tooth enamel is the thin outer covering of the tooth and the strongest substance in the body. It's what makes your teeth white and it exists to protect the crowns of healthy teeth. Tooth decay is the destruction of tooth enamel.

When you eat or drink foods containing sugars or starches, the bacteria in plaque produce acids that attack tooth enamel. The stickiness of the plaque keeps these acids in contact with your teeth and after many such attacks, the enamel can break down and a cavity forms.

Tooth enamel is the white outer covering of a tooth. Its composition makes it the hardest material in the body. Enamel protects the inner part of the tooth, where the nerves are. Fractured, decayed, or severely worn enamel may cause the tooth to hurt or become sensitive to hot, cold, or sweet food/drink.
Tooth enamel is the outer layer of the crown of your tooth. It is a hard protective layer that can be resistant to cavities if cared for properly. When you brush with fluoride or drink fluoridated water the fluoride is incorporated into the enamel and makes it stronger.

Tooth enamel is the outermost layer of the portion of the tooth not surrounded by bone. It is the hardest material in the body, harder than even bone. It is made up of calcium hydroxyapatite crystals surrounding a mixture of various proteins. It is susceptible to degradation (demeralization) by acid. This acid comes from two major sources. The first is acid-producing bacteria that can inhabit the surface of the teeth (which causes tooth decay). The second is from external influences such as stomach acid (from frequent vomiting or esophageal reflux/heartburn) or acidic liquids like soda. If the enamel becomes too thin, the tooth can be weaker or sensitive to cold. 

Tooth enamel is the hard outer layer of the tooth. It can be damaged from plaque that accumulates on the tooth. The acids from the plaque can eat a hole into the tooth which is a cavity. Brushing and flossing helps to remove the plaque and protect the enamel.
Jonathan B. Levine, DMD
Tooth enamel is a thin layer of calcified material that covers the crown’s surface, and it’s responsible for that translucent glow that teeth have. Enamel is composed of enamel rods that look like, well, rods, but they're very tiny and there are hundreds of them threaded in there. Each rod is composed of a mineral called hydroxyapatite. The hydroxyapatite is made up of a matrix of calcium and phosphate crystals. The tighter the matrix’s structure, the harder the enamel is. The thing about enamel is that, no matter how “loose” its structure, it is always going to be the hardest substance in your entire body.
Smile!: The Ultimate Guide to Achieving Smile Beauty

More About this Book

Smile!: The Ultimate Guide to Achieving Smile Beauty

Renowned dentist and creator of the GoSMILE product line Dr. Levine offers this complete guide to getting a whiter, brighter smile. 15 photos & illustrations.
Enamel is the tough, hard, outer protective shell on our teeth. It is commonly in the range of 1.5 mm thick. When enamel is exposed to acids, most commonly those acids produced by decay-causing bacteria, the enamel gradually breaks down. The decay process then progresses into the next deeper layer of tooth structure, the dentin. Since dentin is not as hard as enamel, the decay progresses much more quickly in the dentin. Ideally, the decayed area of the tooth ("cavity") should be cleaned out and restored ("filled") before it reaches into the dentin. 

A dental exam ("check-up") twice/year will catch decay before it gets deeper, more costly, and more involved to restore.
Essentially, tooth enamel is what you see when you glance at your smile or at another person's smile. The natural outside covering of the crown of the tooth is the hardest naturally occurring substance in the human body. It is nearly all mineral with a small amount of organic binder. It is relatively thin -- 1.5 mm thick at its greatest dimension -- but remarkably strong and resistant to wear.

The greatest bulk of a natural tooth is made up of dentin, but it is the enamel that shows above the gums when you smile. Oddly enough, the quality of enamel is not opaque white, but rather translucent (allows light to pass through it). It is the combination of the natural color of the underlying dentin plus the translucency of the enamel that gives the tooth it's light appearance. Most teeth are more ivory or eggshell in color and not white.
Enamel is the hard outer shell of teeth. It is the hardest substance in the body, but is still subject to fracture and acid erosion.
Tooth enamel is the hard protective layer that covers the crown part of the tooth (the part of the tooth that is visible in the mouth). It is the hardest substance in the human body (!) and if it gets worn or damaged, it could have dire consequences for the health of the tooth. 

Of course, having healthy tooth enamel is very important in preventing tooth decay/cavities, but that's only part of the story. Interestingly, tooth enamel is one of the only body tissues that doesn't regenerate itself when it is damaged, which could indicate that it is supposed to last a lifetime---which means that there is no such thing as "normal" tooth wear. Worn tooth enamel could indicate a problem with the bite (i.e. the way the upper and lower teeth come together when biting or chewing) or could be a sign of clenching or grinding, especially if the enamel is worn at the gum line.
Healthy tooth enamel can also keep teeth from becoming sensitive. In areas where there has been gum recession, those teeth can be sensitive because the roots of the teeth (which were previously covered with gum tissue) don't have a protective enamel layer on them.

If any of your teeth are sensitive to heat or cold, or if you see signs of worn or damaged enamel (especially along the gum line or on your lower front teeth where the enamel is thinnest in many cases) be sure to see your dentist right away to have these areas checked. It could help you prevent more serious problems later! 

Tooth enamel is the hard outer shell of a tooth - it's generally smooth, strong, and even a little shiny when really clean. Think of the outer shell of a piece of Chiclet gum. It's also harder than any bone - in fact, it's the hardest substance in your body. But it's not impervious. In fact, over time, enamel will wear away from acids and bacteria/plaque, causing cavities (a hole in the enamel / tooth.) But we have tools to take care of your enamel - brush and floss - your beautiful tooth enamel will thank you.

Tooth enamel is the outer surface or coating of a tooth. Tooth enamel is made of a very hard substance that forms a shell, which protects a tooth's sensitive internal structures. However, tooth enamel is not indestructible. If you don't brush your teeth and floss daily, a sticky, bacteria-filled film called plaque can grow on teeth and destroy enamel.

Enamel is the hardest and the most mineralized substance in the human body. It is the outer most layer of the tooth that naturally protects the inner layers of the tooth. If the enamel softens with a caivity then it can no longer protect the tooth and the tooth can become sensitive. 



Continue Learning about Oral Health

Protect Your Teeth and Gums From Diabetes
Protect Your Teeth and Gums From Diabetes
"The bacteria that live in your mouth love sugar," explains William DeVizio, DMD. "People with diabetes often have higher levels of sugar in their bod...
Read More
Can I have gum disease and not know it?
American Dental AssociationAmerican Dental Association
You can have gum disease without any clear symptoms. That's why regular dental checkups and periodon...
More Answers
7 Worst Foods for Tooth Enamel Loss
7 Worst Foods for Tooth Enamel Loss7 Worst Foods for Tooth Enamel Loss7 Worst Foods for Tooth Enamel Loss7 Worst Foods for Tooth Enamel Loss
Find out the worst foods for tooth enamel loss and acid erosion in teeth.
Start Slideshow
Is Teeth Whitening Safe?
Is Teeth Whitening Safe?

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.