Hi...
Firstly we need to know when was this x-ray taken...
Is it recent or is it 3 months old.
If it is recent I can see some remaining infection in the tooth let your dentist know he may retreat the tooth.
And try to get your capping done after your tooth is treated completely and is pain free.
Next Steps
Consult your dentist again
Health Tips
Keep maintaining good oral hygiene and do warm saline rinses.