THE TEETH. 



643 





spokes. Whether the nerve-fibers directly inosculate with the dentinal fibers, 

 I am unable to say ; but I can positively maintain that an indirect connection 

 of the two is established by the intervening reticulum of living matter. (See 

 Fig. 280.) 



The results of my researches of normal pulp are as follows : 



1. The dental pulp is a variety of connective tissue termed myxomatous, rep- 

 resenting its embryonal form. Pulp-tissue, therefore, is a remnant of embryonal 

 tissue, and kindred to the formations termed " adenoid tissue." 



2. The myxomatous tissue of the pulp is intermixed with a delicate, fibrous con- 

 nective tissue in varying amount. Pulps 



entirely, or nearly, built up by fibrous 

 connective tissue are not to be considered 

 physiological. 



3. The pulp-tissue is traversed by a 

 system of blood-vessels viz. : arteries, 

 veins, and capillaries. Arteries, however, 

 are not invariably found. Lymphatics in 

 small numbers are also present. 



4. The pulp-tissue is richly supplied 

 with nerves, which as bundles of medullated 

 nerve-fibers traverse the myxomatous tissue. 

 Toward the periphery of the pulp they be- 

 come non-medullated, and terminate as 

 minute beaded fibrjllce in knobs or between 

 the odontoblasts. 



5. The odontoblasts, at the periphery 

 of the pulp, are rows of bioplasson forma- 

 tions, in part with nuclei i. e., medullary 

 corpuscles such as we see wherever a new 

 tissue arises from a former. 



6. The dentinal fibers originate between 

 the odontoblasts. Being formations of liv- 

 ing matter, they are in direct connection 

 with the reticulum of living matter ; first 

 of the odontoblasts, and afterward of the 

 basis-substance of the dentine. The con- 

 nection between ultimate nerve-fibrillm and 

 the dentinal fibers is very probably indirect. 



Pulpitis. I have examined a large num- 

 ber of specimens of pulpitis, but have 

 not met with this process unless in pulp- 

 chambers more or less reduced in their caliber by a new formation of secondary 

 dentine. If pulpitis occurs at all without the previous formation of secondary 

 dentine, this must be rare. Even where primary dentine is invaded by the 

 inflammatory process, traces of secondary dentine are visible scattered along 

 the pulp-chamber, and the probability is admissible that the secondary dentine 

 has been destroyed by the inflammation to a great extent before the primary 

 dentine was reached. 



The main characteristic of this process is the appearance of a large number 

 of inflammatory or medullary corpuscles in the pulp-tissue. These corpuscles 

 arise from the bioplasson formations as well as from the living matter hidden 



FIG. 280. PULP OF A TEMPORARY 

 MOLAR. STAINED WITH CHLO- 

 RIDE OF GOLD. 



M, myxomatous tissue ; O, rows of 

 medullary corpuscles so-called odonto- 

 blasts; D, dentine; F, dentinal libers ; N, 

 terminal non - medullated nerve - libers. 

 Magnified 1200 diameters. 



