A cap is almost most of the time compulsory to be placed post-RCT to increase the longetivity of the RCT treated tooth and ease of eating anything. The amount of tooth reduction depends upon the various cap which are available and the amount space available and required for a cap to be placed comfortably. Do not worry.
Next Steps
wait for the cap to be placed
Health Tips
follow pos-cap placement instructions. doing gum massage around the cap area will help prevent any gap issues between gums and tooth