The main factors that contribute to tooth decay is bacteria and a diet high in sugar and starch. There are over 500 different types of bacteria that are normally present in the mouth. These bacteria combine with food and saliva to form a sticky substance called plaque that attaches to teeth. Foods rich in starches add to the stickiness of the plaque, which begins to get hard if it remains on the teeth after a couple of days, and turns into tartar or calculus. Bacteria in the plaque convert sugar into acid that dissolves the tooth structure causing holes, or cavities, often requiring a filling.
What is a filling?
Dental filling is described as a way to restore a tooth which is damaged by decay back to its normal shape and function. When your dentist gives you a filling, they will first remove the decayed material, clean your affected area and fill out the cleaned cavity with a filling material. Through closing off those areas where bacteria may enter, a filling will also prevent further decay.