I had dental work done to put in a replacement crown last week, and now my mouth is full of sores. why is this?

Trama: Having dental work performed like the procedure to replace a crown can cause some local trama resulting in an outbreak in mouth sores. This can be from the injection sites, medicaments used, manipulation of tissues, drying of area, etc. This a reaction by your body to this trigger which cause ulcerations and gingival inflammation. These lesions will go away within the week. Gentle care only.

Canker sores: There are variety causes of canker sores including stress, a weakened immunity system, allergies, hormones and vitamin deficiencies and dental treatment. It will probably heal on its own in a week or so. You can rinse with warm salt water to ameliorate the pain. Res.: if your canker sore is extremely sore or doesn't begin to heal within a few days, contact your dentist.