Principle secretory cells found in the single layer outlining the pulp (Ourtermost zone of pulp)
Fibroblasts
Odontoblast
Ameloblast
Undifferentiated cells
The outermost odontoblast layer,(Single layer outlining pulp ) contains odontoblasts as principal secretory cells for Dentin while they also secrete Collagen Type 1 and type 5 collagen fibers