Teeth may become mobile for a number of reasons. The only way to reverse the effects is to find out what the cause is.
The answer to this question is always “no”. Uncategorically. In some cases, there is no real problem and it is just the cement that holds the dental crown in place that has been dissolved or otherwise compromised, but the problem is, you need a trained medical professional to be able to determine why and how the dental crown fell off. But the crown may be damaged, the tooth may have decayed, and you may not be able to re-adhere the dental crown without causing damage. The best thing to do in these cases is to wait it out until you can go back to your dentist and get the dental crown put back by a professional.
Temporary dental crowns are the crowns that you wear while the dental laboratory is making your final, perfect dental crown. These are necessary only as a hold over, so that you are not toothless in the interim period between the time you lost a tooth or part of it, and the time you get your dental crown. This is usually about a week, but certain circumstances (holidays, illness, scheduling, locational problems, problems with the final crown that require more time to fix etc.) may extend this period of time. Temporary dental crowns fall off because they are not meant to last for a long period of time, but only a short one, and when they do, the best thing to do is to call the dentist to get another one.
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