Brief Answer:
Brushing/cleaning teeth before going to bed, after getting up

Detailed Answer:
Thanks for your query. I have gone through your query.
As far as the washing your teeth is concerned, It is better to brush your teeth soon after eating anything in the night time and before eating anything in the morning.

The reason for cleaning the teeth following eating(in night time) is, after eating the food debris will get adhered to the teeth surfaces, if you fail to clean these debris, this will form a hardened deposit called the calculus. This calculus contains microorganisms and they produce acid which dissolves the teeth and bone resulting in decayed tooth and gum infection respectively. The functions of saliva will be less since the salivary secretions are less during night time because of the lack of stimulus.
The reason for brushing your teeth before eating anything or after getting up from the bed is, there will be growth of microorganisms during night time due to lack of functions of saliva.
So i advise to brush your teeth just before going to bed and after getting up from bed. I also advise you to rinse your mouth soon after eating anything.
I hope i have answered your query. If any queries are there reply me back. Take care.

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