Tooth pulp is the innermost layer of your tooth and it contains blood vessels, nerves, and connective tissues that reach the roots. The pulp handles three primary functions: Sensory function in response to hot and cold Formation of dentin (the hard secondary layer) Nourish the tooth via blood vessels Pulp does much for your tooth, however, it is not necessary to keep the tooth alive. Surrounding tissues can support the tooth even without the pulp.