We have always been advised by our dentist to brush our teeth twice a day – right after we get up and right before we sleep. But how many of us actually follow it? Not many.

Though all of us brush our teeth in the morning but the rule of brushing at night is something we conveniently skip, because it isn't considered sacrosanct unlike brushing in the morning.
If you are nodding your head in guilt, this article is for you.
The bacteria that reside in your mouth feasts upon the food that you eat. These bacteria later excrete waste material, which is highly acidic and can break the tooth enamel leading to cavities and tooth decay.
When you sleep without brushing, the plaque starts to calcify and harden your teeth. And it gets worse with time because the calcified plaque is impossible to remove with brush or floss. The plaque build-up can lead to bad breath, gum infection, gum bleeding and swollen gums.
Why brushing at night is more important
If you do not brush your teeth before sleeping, you allow the plaque to grow and mature undisturbed overnight, which can even lead to colonization of the acid producing bacteria.
Brushing before bed does these three good things

1. Reduces acid build up

Your mouth is constantly building acid. The saliva in the mouth neutralises the acid with the calcium present in it. But during nighttime, since the saliva production is low, the acids gets accumulated. By brushing your teeth at night, you ensure that saliva secretion does not fall by the fluoride present in the toothpaste. This prevents your teeth from getting corroded.

2. Reduces bacteria multiplication

The saliva reduces the bacteria from multiplying. Thus, keeping your saliva secretion maintained by brushing before bed is very important.

3. Reduces food particles decay

The tiny food particles get stuck in your mouth rot overnight. It is best to hit the bed with a clean mouth to prevent decayed food particles playing foul in your mout

Source: indiatimes.com