1. A delta fibers - myelinated fast conducting, larger diameter, associated with Sharp pain
2. C fibers - unmyelinated slow condiction, smaller diameter, assiciated with Dull, Diffusepain.
-As approach coronal portion of pulp, myelinated nerved lose myelin sheaths.
-Some go up dentinal tubules and play a role in sensitivity
-No synapses with nerves and o-blast process