Differential changes in epithelial thickness of oral and pathological odontogenic epithelia in response to inflammatory cell infiltrate

Abstract

Background; Oral and odontogenic epithelia do not always fulfill the known histological features to be diagnosed as specific entities due to many factors including infection. Objectives: This study investigated the changes in thickness of buccal epithelium, the epithelium of dentigerous cysts and the epithelium of keratocystic odontogenic tumours in relation to varying degrees of infiltration by inflammatory cells. Methods: Histological preparations of biopsies of the buccal mucosa from 22 volunteers were compared with those from 23 dentigerous cysts and 18 odontogenic keratocysts for inflammatory cell infiltrate and epithelial thickness. Results: Epithelia in dentigerous cysts showed an increase in thickness from a mean of 64.6 ± 8.2 μm to 178.2 ± 11.3 μm in tissues presenting with low and severe inflammatory cell infiltrate respectively. Likewise, epithelial thickness in keratocystic odontogenic tumours showed an increase from a mean of 69.3 ± 9.9 μm to a mean of 148.3 ± 11.3 μm in tissues presenting with low and severe inflammatory cell infiltrate respectively. In both cases, the change in epithelial thickness correlated with the degree of inflammatory cell infiltrate. Conclusions: Inflammatory cell infiltration induces increased thickness of pathological odontogenic epithelia and this could present challenges to histological diagnosis of these conditions.