Distinctive molecular composition of human gingival interdental papilla.
BACKGROUND
Gingiva is composed of attached and marginal (free) gingiva and interdental papilla. Increasing esthetic demands in dentistry have created a need to restore all parts of the gingiva. However, the interdental papilla has limited regeneration potential compared to other parts of the gingiva. It also is more susceptible to gingival overgrowth, suggesting that it has distinct cellular and molecular properties from other parts of the gingiva. Very little is known about the possible differences in the molecular composition of different parts of the gingiva.


METHODS
We compared the expression of a set of key molecules in interdental papilla and marginal gingiva from seven healthy subjects by immunohistochemical staining.


RESULTS
In the interdental papilla, immunoreactivity for integrin alphavbeta6 and cytokeratin 19 in the oral epithelium was significantly higher than in marginal gingiva. Expression of type I procollagen, extra domain A (EDA) and extra domain B (EDB) fibronectin isoforms, tenascin-C, transforming growth factor-beta (TGF-beta), connective tissue growth factor (CTGF), and the signaling molecule son-of-sevenless (SOS)-1 also were increased in the interdental papilla. The expression of small leucine-rich proteoglycans decorin, biglycan, fibromodulin, and lumican in the interdental papilla was partially different from the marginal gingiva.


CONCLUSIONS
Molecular composition of the interdental papilla is distinct from marginal gingiva. Increased expression of molecules normally induced in wound healing (alphavbeta6 integrin, fibronectin-EDB and -EDA, tenascin-C, type I procollagen, TGF-beta, CTGF, and SOS-1) suggests that the cells in the interdental papilla are in an activated state and/or inherently display a specific phenotype resembling wound healing.
Csiszar
Andrea
A
Faculty of Dentistry, Department of Oral Biological and Medical Sciences, Laboratory of Periodontal Biology, University of British Columbia, Vancouver, BC.
Wiebe
Colin
C
Larjava
Hannu
H
Häkkinen
Lari
L
D000328:Adult; D000368:Aged; D003239:Connective Tissue Cells / Q000737:chemistry; D005260:Female; D005353:Fibronectins / Q000096:biosynthesis; D005881:Gingiva / Q000737:chemistry* / Q000166:cytology* / Q000378:metabolism; D006133:Growth Substances / Q000096:biosynthesis; D006801:Humans; D007150:Immunohistochemistry; D016023:Integrins / Q000096:biosynthesis; D053539:Keratin-19 / Q000096:biosynthesis; D008297:Male; D008875:Middle Aged; D012038:Regeneration; D020664:Son of Sevenless Proteins / Q000096:biosynthesis
D005353:Fibronectins; D006133:Growth Substances; D016023:Integrins; D053539:Keratin-19; D020664:Son of Sevenless Proteins