Erythematous and reticular forms of oral lichen planus and oral lichenoid reactions differ in pathological features related to disease activity.
BACKGROUND
Common clinical forms of oral lichen planus (OLP) and oral lichenoid reactions (OLR) are erythematous (ERY) or reticular (RET). The purpose of this study was to find histopathological changes that differ between these forms.


METHODS
Epithelial thickness, epithelial proliferation rate, apoptosis, and HLA-DR expression were compared among 10 reticular and 12 erythematous lesions, and 11 normal oral mucosa samples (NOM).


RESULTS
The epithelium in ERY was thinner than in NOM, whereas RET showed values between ERY and NOM. Cell proliferation increased significantly in ERY as compared with RET and NOM, with no difference between RET and NOM. Relative numbers of epithelial cell nuclei displaying visible chromatin condensation were reduced in ERY form.


CONCLUSIONS
The markedly increased cell proliferation in ERY supports the notion that this form displays a higher disease activity as compared to RET. It can therefore be important to study each disease form separately.
Karatsaidis
Andreas
A
Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway. akaratsa@odont.uio.no
Schreurs
Olav
O
Helgeland
Kristen
K
Axéll
Tony
T
Schenck
Karl
K
D001706:Biopsy; D004277:DNA, Single-Stranded / Q000378:metabolism; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology*; D004848:Epithelium / Q000378:metabolism / Q000473:pathology*; D006684:HLA-DR Antigens / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D017676:Lichen Planus, Oral / Q000145:classification / Q000378:metabolism / Q000473:pathology*; D009061:Mouth Mucosa / Q000378:metabolism / Q000473:pathology
D004277:DNA, Single-Stranded; D006684:HLA-DR Antigens; D019394:Ki-67 Antigen