When a tooth is damaged, broken or decayed and restoration (filling) is not good enough to make tooth functional then extra -coronal- restoration (cap or crown) is advisable.
Fabrication of crown is two step procedure.
At the first step the tooth that needs a crown is cut all around the tooth in a certain manner giving it a specific shape with a highly precise technique.
It’s impression is sent to lab along with the shade.
The prepared tooth is covered temporarily with a temp crown.
In about a week, crown comes back from Lab, temp crown is removed and new crown is inserted and checked.