THE DENTAL PULP 213 



of the plexus form synaptic connexions with nerve-end cells 

 which are present in a distinct row among the odontoblast 

 cells on their pulp aspect (fig. 129). 



These cells are mostly stellate in form and associated 

 in groups. Each cell is provided with a distal process or 

 axon, which is unbranched and passes direct to the dentine, 

 where it enters the dentinal tube in company with the dentinal 

 fibril but forms no connexion with it. Other processes or 

 ' dendrons ' are given off from the peripheral portions of 



FIG. 128. Human pulp. Ground section (Weil process: iron and 

 tannin), b. Blood-vessel. Axis cylinder of medullated nerve expanding 

 in a brush -like form at crown of pulp. ( x 600.) 



the ' end cell ' (as it may for convenience be called), which 

 are branched, and pass to the odontoblast cells to form 

 a delicate network around them and communicate with the 

 dendrons of neighbouring ' end cells '. The dendrons from 

 one ' end cell ' do not become directly continuous with those 

 from neighbouring ' end cells ', but their communications 

 with these as with the fibres of the deep plexus (or plexus of 

 Raschkow) are synaptic (see fig. 129) ; for it has been shown 

 that throughout the nervous system each nerve with its 

 nerve-end body forms a separate and distinct neuron, and the 

 impulses which pass from cell to cell are passed across 



