How long does it take for a tooth that has just dentin with no enamel to get extracted if you don't look after it properly?

Extraction of tooth: The amount of time it would take to extract a tooth depends on which tooth is involved, and how much of tooth structure is still remaining. Usually 30 to 45 minutes.

Question: You should be able to maintain your tooth for a long time even with the enamel missing. Sugar is the main cause of decay so If you limit your sugar intake and brush and floss regularity you may be able to keep it for your entire life. Putting a crown in this tooth would benefit it as well. The crown would take the place of the missing enamel. Hope this helps :).

Not long: How long your tooth lasts depends on how well you look after it. See a dentist for treatment. Do not delay.

????: There is no way to answer that question over the internet, sight unseen, without an x-ray and knowledge of your oral hygiene, eating and drinking habits, etc. See a dentist to discuss your treatment options and how best to maintain a healthy mouth.

Variable: Variable. If the tooth is kept clean it may never decay. Ask your dentist for advice.