Ideally if your dentist
has advised you for the extractions of wisdom teeth, then its better to get them removed soon specially if they have cavities.
You need to eat before extraction if it will be done under local anesthesia
so that you dont feel uncomfortable or weak after the extraction as you will not be able to eat after it for a couple of hours. So to keep your strength up have healthy food before visiting your dentist. Also use cold
compress from outside in the area of extraction to reduce/avoid swelling.
After the extraction, when your dentist recommends, you should have cold food like ice creams and cold milk etc. After 24 hrs of extraction you should do warm saline gargles 3-4 times / day as it will help in healing.