What is the difference between a cavity and a filling?

The former is the problem, latter the solution.

A cavity is defined as “an empty space within a solid object, in particular, the human body”.

Our bodies have many cavities. The mouth is called the oral cavity, our stomach is housed in the abdominal cavity, etc.

Your tooth having a cavity literally translates to a “hole” in the solid tooth. This is the result of the bacteria in your mouth fermenting the food, under specific conditions, to dissolve the minerals present in your enamel and dentin.

We need the following elements for a cavity to form -

• Host – Tooth structure

• Substrate – Food

• Bacteria – naturally present in saliva

• Time

The normal pH of saliva is 6.7. When certain foods/beverages/medications cause the pH of the saliva to drop below 5.5, bacteria are activated to start the process of forming cavities. When the pH goes above 5.5 again, the process halts and only resumes when it drops again.

This is why certain foods/beverages are bad for your teeth and others that are better.

This is also why the mechanical action of tooth brushing and flossing + the chemical action of using toothpaste and mouthwash, can be so useful. It helps break the cycle of bacteria at work!

What is a filling?

A filling is essentially the material that is packed in the cavity after it has been cleaned out, i.e., made free of bacteria, infected tooth structure, food debris, and other unwanted particles.

The filling material that dentists use is supposed to replace the missing tooth structure and allow the tooth to return to its normal form (shape) and function (chewing/biting).

There are mainly two kinds of fillings your dentist can recommend. Sometimes, they will recommend a crown. Next week we will talk about the different kinds of filling materials and also discuss what a dental crown is and does.

Till then,