Good morning. I think you are mentioning the 6th tooth , the molar. It is the main teeth for chewing and grinding your food. Without the 1st molar you chewing efficiency drastically decreases.
Additionally a fractured tooth in the mouth is a source of infection, and more often than not it leads to abscess and swelling and pain later on.
Next Steps
Get the tooth piece extracted and opt for an implant or crown and bridge.
Health Tips
Kindly do not avoid such treatment till you don’t have pain