I was first led to the histologie examination of pulp hypertrophy by the desire to find the conditions of the nerve supply in this so highly-altered pathologic tissue; in the study of the nerves I found not only what I expected—partly complete absence of nerves and partly marked decrease of nerve fibers, thus explaining the great difference in sensitiveness—but also some other very interesting discoveries which I believe are new.
Pulp hypertrophy is to be considered as a new tissue formation due to chronic pulpitis from exposure through more or less complete destruction of the overlying protective tissues. This new growth consists of a comparatively coarse granulation tissue in which three layers can be distinguished. The outer layer consists of a thick stratum of white blood or pus corpuscles beginning to break down, then follows a somewhat wider zone consisting of a proliferation of endothelial cells and capillary vessels
RÖMER O. PULP HYPERTROPHY OF THE TEETH.. JAMA. 1904;XLII(5):304-305. doi:10.1001/jama.1904.92490500024001h