An electron microscopic study of the regeneration of gingival epithelium following gingivectomy in the dog

Abstract

Regeneration of dog gingival epithelium following gingivectomy was studied electron microscopically. The wounds were sampled at 24 hour intervals until 14 days following the operation. From a relatively undifferentiated migrating epithelium the process of differentiation resulted in the following sequence of events. In areas where the cells made contact with the fibrin of the blood clot, a basal lamina and hemidesmosomes appeared, the number of cytofilaments increased as did the number of desmosomes and free ribosomes. Further differentiation in the masticatory epithelium was related to keratinization. The cytofilaments in the cells of the upper layers became grouped into bundles, membrane‐coating granules and keratohyalin granules appeared, the intercellular spaces in the superficial layers became narrowed and finally a stratum corneum was formed by the seventh day. In the epithelium lining the crevice a stratum corneum was not formed, the intercellular spaces in all the layers remained wide and the cells in the upper layers developed a relatively prominent Golgi apparatus and numerous membrane‐bound granules throughout their cytoplasm. The result of the differentiation in the regenerated gingiva was the formation of masticatory and crevicular epithelium which were ultrastructurally similar to the two epithelia originally present.

Histomorphometric study of the healing of human oral mucosa after gingivoplasty and low‐level laser therapy

“…According to Ramfjord [27], the epithelium migrates 0.5 mm/day from the borders to the center of the wound. Thus, reepithelization can last up to 14 days depending on the size of the lesion [28,29]. In the present study, reepithelization of the entire wound area was observed at 7 days after surgery in all patients, in agreement with other studies monitoring gingival healing in humans [30,31].…”

The present status of the gingivectomy procedure

“…Surface epithelialisation took 1-2 weeks, but complete healing of the sulcular epithelium required 4-5 weeks. Following this epithelial migration, differentiation occurred and the final ultrastructural appearance was similar to that of the original masticatory and crevicular epithelium (Innes 1970). A subsequent study using the electron microscope demonstrated that epithelial reattachment after gingivectomy occurred in 12 days, and that hemidesmosomes and basement lamina regenerated against both enamel and cementum surfaces (Listgarten 1972).…”

Ultrastructure of squamous epithelium during wound healing in palatal mucosa of guinea pigs

“…They occurred mainly in aggregates, which in tbe epitbeUal migratory lip cells assumed the character of short tufts and delicate bundles compared with tbe vigorou.s bundles seen in tbe cells after continuity bad been established (Figs. 9,13,14).…”

“…It is generally accepted tbat epithelial wound healing is followed by a transient reduction in the amount of tonofilameots (13,16,18,19). Recent quantitative data have confu-med a decrease in toDoIilament bundles relative to a unit volume of cytoplasm in migrating epithelium to be followed by a timely increase subsequent to wound closure (1), The latter event coincides with a relative increase in density of non-bundled tonofilaments ( Table 2).…”