Visualization of junctional epithelial cell replacement by oral gingival epithelial cells over a life time and after gingivectomy

Abstract

Junctional epithelium (JE), which is derived from odontogenic epithelial cells immediately after eruption, is believed to be gradually replaced by oral gingival epithelium (OGE) over a lifetime. However, the detailed process of replacement remains unclear. The aim of the present study was to clarify the process of JE replacement by OGE cells using a green fluorescent protein (GFP)–positive tooth germ transplantation method. GFP-positive JE was partly replaced by OGE cells and completely replaced on day 200 after transplantation, whereas there was no difference in the expression of integrin β4 (Itgb4) and laminin 5 (Lama5) between JE before and after replacement by OGE cells. Next, GFP-positive JE was partially resected. On day 14 after resection, the regenerated JE consisted of GFP-negative cells and also expressed both Itgb4 and Lama5. In addition, the gene expression profile of JE derived from odontogenic epithelium before gingivectomy was partly different from that of JE derived from OGE after gingivectomy. These results suggest that JE derived from the odontogenic epithelium is gradually replaced by OGE cells over time and JE derived from the odontogenic epithelium might have specific characteristics different to those of JE derived from OGE.

Junctional epithelium and hemidesmosomes: Tape and rivets for solving the “percutaneous device dilemma” in dental and other permanent implants

“…Further investigation showed a slow-cycling population of Wnt-responsive cells in the base of the JE as a repository of stem cells, which was indeed hinted at by earlier work [ 307 ]. This supports a model whereby quiescent and active stem cells coexist in the JE [ 315 ].…”

Formation and regeneration of a Wnt‐responsive junctional epithelium

“…Is the JE a separate entity, or is it an adaptation of the OE? Recent data argue that it is an adaptation because the OE eventually contributes cells to the JE (Kato et al, 2019). Our data support the first part of this model, in which the JE and its Wnt-responsive status are established at its origin from the REE (Figure 1).…”

“…The historical literature states that the JE can regenerate, and more recent studies suggest that it does so via contributions from the adjacent OE (Kato et al, 2019;Nakamura, 2018). The OE and JE, however, are histologically distinct since the former is keratinized and the latter is not (Figure 3 On post-gingivectomy (GV) day 3, a dense cellular infiltrate occupied the injury site (Figure 3(c)).…”

“…It is generally thought that the JE is gradually replaced by cells from the OE (Yajima-Himuro et al, 2014) and that following its surgical removal, the JE can rapidly reform from the OE (Kato et al, 2019;Listgarten, 1967Listgarten, , 1972Masaoka et al, 2009;Wazen et al, 2015).…”

Uremia causes dysbiosis-mediated periodontal disease

“…The histological changes caused by uremia are similar to those caused by other forms of periodontal disease, including replacement of specialized junctional epithelium [19] with proliferating epithelium with deep sulcal folds, which appears similar to the pocket epithelium seen in humans with periodontal disease [20]. We also demonstrated aberrant bone formation in the alveolar bone crest adjacent to in amed periodontal structures.…”