Tooth Decay vs. Cavities: What’s the Difference?

young woman suffering from tooth pain

When you hear “tooth decay,” you probably think of a cavity. You may also think of cavities as an inevitable part of life, but they’re not. Cavity prevention is crucial to maintaining your oral health and avoiding any pain down the road. So what’s the difference between a cavity and tooth decay? Let’s break it down.

Everyone has a cavity at some point in their lives

When you have a cavity, it means that the enamel on your tooth has been damaged by tooth decay. The enamel is the hard white outer layer of your teeth (it feels smooth to the touch), and it protects the inner part of your tooth called dentin, which contains nerves and blood vessels. When these are exposed to bacteria in plaque on your teeth, they can trigger an infection in the pulp inside your tooth. This then causes pain when there’s a cavity.

If left untreated, a cavity can cause even more damage. Not only do you risk losing one or more of those vital nerves and blood vessels (which can lead to sensitivity), but also, as this decay spreads deeper into other parts of your tooth structure. For instance, root canals could threaten its ability to properly support itself for chewing food—and this could collapse altogether.

Tooth decay is the leading cause of cavities

The most common type of tooth decay is called a cavity. Cavities form when bacteria in dental plaque (a sticky film that forms on the teeth and gums) break down sugars in your mouth. The bacteria release acids, which eat away at the enamel that coats your teeth and expose the dentin below it—the layer just under your enamel.

This makes it easier for bacteria to continue eating away at the dentin and creating a hole, or cavity, in your tooth. You can treat cavities by filling them with restorative materials like composite resin, porcelain, or gold crowns.

Your mouth is full of natural bacteria

You have bacteria in your mouth. 99% of bacterias are harmless, and some bacteria benefit your health. However, if you don’t take care of your teeth or let that natural flora build up over time, it can cause problems. Bacteria can cause cavities and gum disease by producing acid that damages tooth enamel.

Small amounts of food and liquid are left behind on your teeth when you eat and drink. This acts as a “nourishment” for bacteria, which causes them to grow and multiply quickly. As more bacteria forms in your mouth over time, acid is produced, which can cause damage to the tooth structure. The result is cavities or holes in your teeth that need to be treated with fillings or crowns.

The only exception for cavities or tooth decay is when you have implant dentistry, as dental implants do not allow bacteria to form on them. This is because they are made of titanium, which is not a food source for bacteria. They can even last a lifetime if you take care of them properly.

Cavities are caused by decay, but not all tooth decay results in a cavity

close-up photo of open mouth during an oral checkup

While cavities are indeed caused by tooth decay, not every instance of tooth decay results in a cavity. In fact, many cases of tooth decay do not result in cavities at all.

In other words, your teeth can have been blackened due to bacteria and plaque build-up without causing any damage to the enamel or dentin layer beneath them. If this happens on its own without help (for example, if you have an autoimmune disease that causes gums and other tissue around your teeth to become inflamed), you will need no additional treatment beyond regular brushing and flossing.

How can you prevent tooth decay and cavities?

Tooth decay is a severe problem that can lead to various health issues, including pain and tooth loss. If you want to avoid the need for dental repair or replacement, you must take good care of your teeth from an early age. You can reduce your risk of cavities by brushing your teeth twice daily and flossing once daily.

Additionally, you should visit your dentist regularly for checkups and cleanings. The frequency of these appointments will depend on the condition of your teeth, but most adults should have a cleaning every six months to 1 year.

To Wrap Things Up

When it comes to tooth decay, your best bet is to talk with a dentist about how often you should be visiting them and what prevention measures they can recommend. It’s important to know that even though cavities are caused by decay, not every instance of tooth decay results in a cavity.


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