Please, Check grammar and correct

Hi,
Context:

There are five men in a room. The first is 15 years old. The second is 30. The third is 40.

So the first ask: ' What should a man at the age from 15 to 40 do to preserve his teeth in perfect condition until extreme old age?'
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Is my question correct?
What should men aged 15 to 40 do to preserve their teeth in

Clive, I've watched the video which was made by a famouse Russian dentist who have been living in Saint-Petersburg. He said that children aged 7-14 should use one brushes and toothpastes, children aged 15-18, the other, etc. So each of family members should use their own toothpaste, etc.

Hi,

So is there a question that you still need an answer for?

Clive

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There are a huge number of questions to which I had no answers.

For example,

What toothpaste and toothbrush are best for me? (mouthwash, flossing, etc).

You can tell me that It's very easy to find answers to these questions but I don't agree with you. I've read an interesting article in Russian Men's Health magazine about it, and I wa

Hi,

This is an Englsh Forum. You seem to need a Toothpaste Forum.

Clive