Epulis

Epulis (epulis), connective tissue growths located on the alveolar processes of the jaws; they originate from tissues surrounding the necks and roots of teeth and are functionally connected with the latter. In guides to pathological anatomy and private surgery, E. are considered in the section on tumors of the oral cavity and are classified as fibromas and giant-cell sarcomas (e. sarcomatosa). However, the nature of the latter always seemed unclear, since their benign clinical course was in contradiction with their histological characteristics. Based on histological structure, three groups of E. can be distinguished. The first group includes those forms that represent granulation tissue in various stages of fibrous transformation (Fig. 1). In the process of organization of granulation tissue, areas of bone substance often arise among bundles of collagen fibers through metaplasia; subsequently, these are surrounded by osteoblasts and, through appositional growth, form true calcified bone trabeculae. The second group includes those forms that differ from E. of the first group only by a greater number of blood vessels. Usually these are vessels with a wall of endothelium, partly rounded, and a small amount of connective tissue; sometimes they are so wide and distended with blood that only thin layers of fibrous tissue remain between them, i.e., the tissue as a whole resembles cavernous tissue. In other cases, a picture similar to the so-called angioma hypertrophicum is observed. But in all these E., the main tissue in which the vessels are embedded has the character of granulation tissue, and in many cases one can also verify its gradual fibrous transformation; at the same time, the walls of the vessels thicken, become sclerotic, and their lumens decrease, partly due to the proliferation of the intima (Fig. 2 and 3). The third group includes forms characterized by the presence of giant cells (Fig. 4). In the development of giant-cell E., the primary moment is the proliferation of elements of the vascular walls with the formation of giant cells and the usual cellular forms of granulation tissue; as a result of such "productive destruction" of vessels, as a secondary moment, free blood appears among the tissue elements; blood circulation, although very slow, nevertheless continues. In the process of tissue differentiation of giant-cell E., the giant cells themselves also participate; they break down (discomplex) into separate mononuclear elements of the fibroblastic series (Fig. 5). Thus, the disappearance of giant cells occurs not through their degeneration, but in the process of further differentiation. The discomplexation of giant cells is manifested by the presence among the elements of organizing tissue of cells varying in size, number of nuclei, and contours, which may give the impression of polymorphism, which is in fact apparent, false (Fig. 6). Parallel to the maturation of the tissue of giant-cell E., with its transformation into fibrous tissue, and the restoration of the blood vessels, the masses of blood remaining outside the new vessels undergo organization; as a rule, accumulations of hemosiderin are formed, located along the course of the new vessels, especially at their branching points. Thus: 1) all forms of E. are formations whose tissue is built from typical elements and undergoes a certain cycle of development, ending in the organization of mature tissue; 2) the structure of connective tissue formations appearing as a result of the organization of tissue of any form of E. almost coincides. According to histological structure, therefore, E. belong to granulomas, which are divided into three groups: 1) E. of the simple granuloma type, 2) E. of the vascular granuloma type (angiogranulomas), 3) E. of the giant-cell granuloma type. E. of the simple and vascular granuloma types are inflammatory proliferations of the superficial, supra-alveolar parts of the paradentium. According to histological structure and pathogenesis, many of them are closely related to hypertrophic gingivitis (see). Giant-cell epulides are reactive proliferations of the granulation tissue type, originating from the deep intra-alveolar parts of the paradentium (spongy substance of the alveolar socket and the cambium layer of the periosteum), and in the underlying parts of the alveolar process, changes characteristic of the so-called fibrous osteitis are often found (see Fibrous osteitis).-From the point of view of pathogenesis, the basis for the appearance of giant-cell E. is a long-term increase in functional irritation (mainly mechanical, in the form of pressure and traction) of the paradentium elements by the roots of teeth. When attempting to more precisely determine the place of giant-cell E. among formations arising in the order of pathological growth, based on histological research, the idea of their sarcomatous nature is first excluded (and clinically they never coincided with this concept); they can be distinguished as a separate form of localized fibrous osteitis with a special pathogenesis, which is determined by the special anatomophysiological conditions of this area. Regarding the nature of E., there is no unity of opinion: many continue to consider them as true blastomas, and some, recognizing the transition of giant-cell forms into fibrous ones, classify both types of E. as tumors with the character of osteofibroma, while others even consider it possible to retain the term giant-cell sarcoma. The latter view currently has almost no supporters. Clinically, E. are generally painless, slowly growing neoplasms, reaching the size of a hazelnut or larger; they are located mainly on the outer surface of the alveolar process, more often in the area of frontal teeth and premolars, situated either on a broad base or as if on a stalk; their consistency and color depend on the histological structure, degree of blood filling and pigment content (hemosiderin) in the tissue; thus, E. in the stage of fibrous transformation have a dense-elastic consistency, increasing depending on the degree of ossification, and a pale pink tint; E. of the angio-granuloma type are distinguished by their soft consistency and dark red color. For giant-cell E., a cyanotic with a brownish tint color is characteristic, associated with abundant blood filling with slow circulation and with the deposition of hemosiderin; this color is especially noticeable on the surface of a section through E., where it is often located in the form of separate spots (Fig. 4); and in this respect, this group of E. completely corresponds to the so-called brown tumors (braune Tumoren) observed in fibrous osteitis. Surface ulcerations are usually observed in E. that have reached significant size, in areas subjected to trauma from antagonist teeth. E. are most often observed between the ages of 20 and 40 years and predominantly in women: the ratio of the number of E. in women to men is 3.1:1. In childhood, they are relatively rare: according to Gruener (Grimer), out of 474 cases, 40, i.e., 8.44%, belonged to children under 11 years old (out of 70 cases by A. Ryvkind, there were 7 cases in children from 8 to 14 years; all 7 cases were of the giant-cell type). It is important to note the appearance of E. in women, mainly of the angio-granuloma type, during pregnancy, and some authors describe their independent regression after childbirth. E. of all three groups have a tendency to resorb surrounding hard tissues (bone and tooth roots) and often recur; in the stages preceding fibrous transformation, the tissue of E. is very prone to bleeding, which is naturally most strongly expressed in the angio-granuloma group. Treatment is surgical, with mandatory excision of the periosteum area adjacent to the base of E. and resection of the corresponding, usually small, part of the bone. The roots of destroyed teeth are removed. The removal of still functional teeth in the area of which E. is located should be resorted to only in cases of persistent recurrences.

A. Ryvkind. ERB Wilhelm (Wilhelm Erb; 1840-1921), an outstanding German neurologist. He studied medicine at various German universities (Heidelberg, Munich, Erlangen); in 1864 in Munich he defended his dissertation on picric acid, its physiological and therapeutic effects. In 1875-80, E. was a privat-docent in Heidelberg and an assistant in Friedreich's clinic, from 1880 for 3 years he was a professor in Leipzig, and from 1883 he held the chair in Heidelberg, succeeding Professor Friedreich. His 40-year scientific activity was concentrated almost exclusively on the clinic of nervous diseases: he wrote extensive guides on diseases of the spinal cord and peripheral nerves (1874) and on electrodiagnostics and electrotherapy (1886), which brought him world fame and were translated into Russian. In addition, E. wrote numerous major studies on muscle atrophies (he distinguished new forms among the general chaos of muscle diseases), on tabes dorsalis (E. was one of the first to emphasize the connection of this disease with syphilis), on Thomson's disease, on spinal paralysis, tetany, angiospastic dysbasia, etc. Erb significantly deepened the doctrine of the electrical reaction of muscles and nerves: the so-called reaction of degeneration and myotonic reaction are associated with his name. In addition, E. distinguished the 'bulbar symptom complex', later described by Strümpel and Oppenheim; he also distinguished the 'combined paralysis of the arm and forearm' and was the first in Germany to describe cases of myxedema. E. was one of the founders of the Society of German Neurologists and for a long time was the editor of the official organ of this society ('Deutsche Zeitschrift fur Nervenheilkunde').