What is a cavity?
Cavity comes from the word “cavus”, whose Latin origin means hollow. Therefore a cavity is a hollow opening, or “cave”, in the tooth.
Certain bacteria that live in the mouth cause damage to teeth when in the presence of fermentable carbohydrates (sugars). When these carbohydrates are not cleaned away, the bacteria convert them into acid in as few as 20 minutes. Within hours, the bacteria, acid, food particles and saliva form a sticky, invisible film on teeth called plaque. As long as plaque remains, the acid lingers and attacks the tooth’s hard, outer enamel surface. Tiny holes in the enamel result and this is the start of a cavity.
Once through the enamel, bacteria and acid reach the next layer of tooth, called dentin. This layer is softer and less resistant to breakdown than enamel and the decay process speeds up. Left untreated, the bacteria will eventually reach the middle layer of tooth, called pulp. This is where the nerve and blood vessels supplying the tooth are located. As a cavity advances to the pulp, you will start to feel sensations ranging from a mild discomfort to severe pain. Once bacteria have entered the pulp, a filling is no longer sufficient to solve the cavity problem and root canal therapy is indicated.
How do I get a cavity?
Decay often begins in hard-to-clean areas where you cannot easily remove the plaque layer. Examples are the pits and grooves of the chewing surfaces of back teeth, the contact points between teeth and along the gumline of teeth. Cavities are one of the most common worldwide problems and everyone who has teeth is at risk of getting them.
“Recurrent” decay occurs when a new cavity forms around the borders of an old filling or crown. It is still necessary to brush and floss existing restorations daily along with all of the other teeth since bacteria can nest in the tiny microscopic openings along their edges. If the bacteria succeed in breaking down the tooth structure again, the restoration must be replaced.
Risk factors for cavities
- Genetic predispositions / high natural acids in mouth
- Frequent consumption of foods or liquids high in acid (i.e. soda, white wine, lemon-sucking, dried fruit snacks, etc.)
- Lack of daily brushing and flossing
- Poor brushing and flossing techniques
- Regular consumption / frequent snacking of foods and beverages high in sugar (ie. soda, gum, candy, mints, cough drops)
- Non-fluoridated drinking water
- Receding gums
- Dry mouth (sometimes a side effect of medications)
- Eating disorders
- Heart burn or acid reflux
- Old and failing restorations (crowns and fillings)