A cavity is a small hole in your tooth caused by tooth decay. Over time, bacteria in your mouth create acids that wear down your tooth enamel (the hard, protective outer layer). Once that enamel is weakened, decay can sneak in and form a cavity.
Cavities can happen to anyone — in fact, about 90% of adults have had at least one cavity by the age of 20.
Cavities develop when harmful bacteria form plaque around your teeth which then digest the food we eat and form acids that damage the tooth surface. Plaque does the most damage when it has frequent access to sugary foods, drinks, and other carbohydrates.
If this "acid attack" happens often, and you’re not brushing and flossing regularly, the enamel weakens, and a cavity begins to form.
Plaque is especially harmful when it stays on your teeth too long. Brushing twice a day and flossing daily helps break up that bacteria before it can do damage.
Some cavities don’t cause pain right away — that’s why regular dental checkups are so important. But there are warning signs you can look for:
Sudden tooth pain or aching
Sensitivity to hot, cold, or sweet foods
Pain when chewing or biting
A visible hole or dark spot on your tooth
White spots on the tooth (early sign of enamel breakdown)
Not sure what you’re feeling? When in doubt, get it checked out.
Cavities are not all the same, and some are more noticeable than others. Without a regular oral health routine, they can occur anywhere on your teeth — on the biting surfaces, between teeth, and at or below the gum line.
Your dentist will most likely notice early decay and cavities before you do, especially if the problem is located between your teeth, which may only be visible on an X-ray. This is one reason why regular checkups are so important. Small cavities are easier to treat, and in the early stages of decay, the process may even be reversed with early intervention.
Can cavities get worse over time?
Yes, cavities start small but can grow deeper if they’re left untreated. Here are the 5 stages of a cavity:
Demineralization: The acid in plaque breaks down minerals in your tooth enamel. Remineralization may be possible at this stage.
Enamel decay: The acid has removed enough tooth structure to form a hole in the enamel, your tooth’s outermost layer. Once a hole has formed, you will need to work with your dentist to repair.
Dentin decay: The decay process may accelerate as acids begin to affect the softer layer of dentin under your enamel.
Pulp damage: Once enough dentin is destroyed, the bacteria may infect the pulp. Treatment for pulp damage requires a root canal.
Abscessed tooth: If the infected pulp is left untreated, then it can cause an abscess at the end of the root and into the bone. To treat this, your dentist may drain the abscess, perform a root canal, or possibly even remove the infected tooth.
The type of cavity you have will depend on where it forms on your tooth, which can influence methods of prevention and treatment. Types of cavities include:
Smooth surface cavities form on the smooth, flat surfaces on the sides of your teeth. They usually develop slowly, which gives you time to prevent or even reverse the decay process before it creates a cavity. Fluoride from tap water, toothpaste, rinses, and varnishes or gels from your dentist will help prevent or reverse early smooth surface decay.
Pit and fissure cavities are most common in children and form in the pits and grooves on your back teeth. These cavities typically progress faster than smooth surface cavities. Dental sealants help prevent them from forming.
Root cavities are on the roots of your teeth and develop when gum recession leaves your teeth roots exposed, making those root surfaces more vulnerable to acid released by dental plaque and are most common among older adults, who are more likely to have receding gums. Once formed, root cavities can be difficult to treat.
Recurrent cavities form at the margins of existing fillings or crowns, often from bacteria that leaks through a gap between the tooth and the filling.
Each type may require a different approach, but your dentist will help you choose the right treatment.
Unfortunately, no — once a hole forms in your tooth, it won’t heal naturally. But here’s the good news: early signs of decay can sometimes be reversed with fluoride treatments, good oral hygiene, and diet changes.
It’s all about consistency. Here’s how to protect your teeth:
Brush twice a day with fluoride toothpaste
Floss daily to clean between teeth
Cut back on sugary snacks and drinks
Drink tap water (it often contains protective fluoride)
Visit your dentist every 6 months
Sealants and fluoride treatments can also help, especially for kids or those more prone to decay.
If you are concerned that you have a cavity, then visit your dentist as soon as possible so they can diagnose the problem and discuss treatment options. Addressing the problem early will help you avoid advanced tooth decay, tooth abscesses, and tooth loss.
Cavities develop slowly, and you can proactively prevent them by attending your regularly scheduled dentist appointments and maintaining a daily brushing and flossing routine.
1Cavities. (2021, January 25) from https://www.cdc.gov/oralhealth/fast-facts/cavities/index.html