If the pulp is damaged by deep tooth cavity, root canal treatment needs to be carried out.
The bacteria that has penetrated the tooth through the cavity can kill the pulp. A root canal treatment usually requires more than one dental appointment. At the first appointment all decay is removed and the root canal is opened to remove the dental pulp.
The root canal is then filled with an antibacterial agent. At the next appointment, the tooth is filled with a material that replaces the dead tissue. This it works in much the same way as a tooth filling. After a tooth has been root filled it needs a composite filling or a crown.