208 MICROSCOPIC ANATOMY OF THE TEETH 



Sometimes more than one dentinal fibril arises from 

 a single odontoblast, but in many cases, especially where 

 shrivelled odontoblasts are represented, these appearances 

 are deceptive, several cells with their processes being seen 

 groupad together. 



A dentinal tube is sometimes seen to terminate in a clear 

 space in the matrix between the surrounding tubes, and end 

 in numerous fine terminal branches (fig. 124). 



Vessels of the Pulp 



The blood-vessels of the tooth-pulp enter the apical 

 foramen in one or more arterial branches. They traverse 

 the pulp in company with the nerve trunks (figs. 125 and 127), 

 branch frequently, and ultimately form a vascular plexus 

 beneath the odontoblast layer. While, however, the capil- 

 lary vessels which arise from them for the most part form 

 loops in this situation, many pass across the odontoblast 

 region and are se3n in contact with the forming dentine in 

 developing teeth. 



According to Guido Fischer (6) the capillary vessels in 

 transverse section are seen in two forms one in which there 

 is a distinct adventitia, and smaller ones in which only the 

 endothelial coat is visible. The veins are apparent as open 

 spaces in the connective tissue of the pulp, with very delicate 

 walls. The vessels are in intimate relation with the nerve 

 trunks in the pulp, the latter often partially surrounding the 

 blood-vessels (fig. 126). 



Lymphatics. It has usually been considered that the dental 

 pulp contains no lymphatics, but recent researches appear 

 to have demonstrated that a lymphatic system is present. 

 G. Fischer, writing in 1909 (6), says that lymph vessels, 

 although found around the roots of teeth, are not present 

 in the pulp, but he describes peri vascular lymph spaces as 

 being present, especially around the odontoblasts. Dewey and 

 Noyes, in a recent study of the lymphatic vessels of the dental 

 pulp, describe the work of Schweitzer on this subject and 

 consider that the recent date of this investigation is the 

 reason why it is not sufficiently known, and the statement that 

 there are no lymph vessels in the dental pulp still maintains its 



