What will the dentist do?

It depends on the severity of the pain, if it keeps you awake at night or the paiin does not go after a few mintues then it could be that the nerve has been damaged due to decay - the dentist will offer root canal treatment which usually consists of two visits, the first visit will remove the nerve from the tooth a temporary dressing is put in the tooth, the next appt will be within 5-10 days, if the tooth has not caused further problems, they will complete and fill the tooth. The reason that the tooth may need a crown especially if it is a back tooth is because the tooth will be weakened, please do not take any notice that the back teeth are not important, they are very important.....If the tooth is too bad the dentist may advise that the tooth should be taken out., either option will be upto you.