Tooth decay is people's top dental concern.
Find out the causes and risk factors of dental decay, and how fast it happens.
Already have it? Read about treatments.
So far, no tooth decay? Great - do review how to keep preventing it.
Causes of tooth decay
Acids & bacteria
To appreciate the causes of tooth decay, it helps to know what it is. Tooth decay is the result of acid washing and dissolving the tooth. A dental cavity (hole) is simply localized tooth decay.
Now, the acids causing tooth decay arise in two ways. Chiefly, acids arise from the mouth's bacteria, which naturally convert food (sugars and starches) into acid. Acids also arise from acidic drinks (orange or lemon juice, soda) and foods (kiwis, strawberries).
Triggers of causes
Factors in tooth decay are things, habits, or conditions that help oral bacteria put out acids. Factors include:
- Plaque - Plaque is a major factor in tooth decay. Since plaque on teeth contains bacteria, all their acid washes the teeth.
- Foods and drinks with sugars, starches, or acids - Sugars and starches are what oral bacteria convert to acid. These foods vary in cariogenicity, i.e. how badly their acid decays teeth. Worst are starches that are refined and cooked (cookies, pastries, cereals) and sucrose sugar (table sugar, hard candies). Sugars in milk, raw starches, and fruits are less cariogenic. Sticky foods are more cariogenic than non-sticky foods, because stickiness to teeth implies acids concentrate on teeth.
- Frequent snacking or lengthy sipping - Snacking frequently is also a factor in tooth decay. With each snack, a new bacteria-induced acid attack on teeth ensues. Sipping sugary drinks for long contributes to tooth decay, among them coffee, tea, and soda. The prime example among babies is falling asleep while sipping bottled milk.
- Insufficient saliva - Insufficient saliva speeds up tooth decay, because saliva counters tooth decay. It washes away food debris, starving bacteria of the input for their tooth-decaying acids. Plus, it contains calcium and phosphorus minerals that reverse tooth decay, a process known as remineralization.
- Cracked or loose fillings - Fillings that are cracked or loose invite draw food and bacteria inside, setting off tooth decay.
It takes several years in an adult for tooth decay to pass from the tooth's surface to the root, the stage where cavities are most damaging.
Tooth decay need not be permanent; small cavities can reverse and heal, or stabilize for years. So, upon detecting a small cavity, your dentist may note it, but not target it, and instead check it again at your next dental cleaning.
Root cavities do decay fast, and immediate action is ideal. However, being inside the tooth, root cavities are not apparent and often discovered only too late, making a root canal inevitable.