Ans.Tooth decay is also called as cavity. And nobody likes cavity. It is the most common problem of the teeth faced by children and adults both. Its starts with pin point discolouration of the tooth, and leads to infection in the pulp chamber and the root. The bacteria present in the mouth make acid by reacting with some food substances and this acid causes the demineralization of enamel, then the dentine and eventually infection goes on and spreads to the root.

The tooth decay is a process that occurs over the time. It is caused by combination of some factors like bacterial plaque, food habits, time of the food consumption and neglected oral hygiene. Some factors that increase the risk of tooth decay are:

• Food and beverages: certain food and drinks, which contain high amount sugar and starch and processed ingredients, which increase the risk of cavity . these food items include sugar, ice cream, soda, cake, biscuits, chips, juice, and candies etc.
• Frequency of snacking: more the frequent snacking, more is the acid formation by the bacteria and higher is the risk of demineralization of teeth leading to cavities.
• Oral hygiene: inadequate brushing and cleaning causes more plaque formation that is one of the main causes of tooth decay.
• In infants, bedtime feeding: when babies have a bottle milk at bed time, the sugar content in it causes the decay, which is called as rampant caries.
• Fluoride insufficiency: fluoride is a mineral, which is helps prevent the decay. That’s why a particular amount of fluoride is added in public water and is also the main ingredient of toothpaste and mouthwash.
• Dental prosthesis: sometime wearing the prosthesis may restrict the cleanliness of that area, thus causing cavity.