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Just wanted to tell you that you can brush your teeth any damn time of the day, actually. Can't be arsed right before bed because you only realised you're sleepy when you got sleepy? Busy or hate life in the morning?
Go to bed, get up to brush them later when you can't sleep anyway! Brush them when the terrors awaken you in the middle of the night! Brush them whenever!

As long as you don't do it when the tooth enamel is still soft, you are not beholden to time!