A retrospective comparative study on clinico‑pathologic features of oral lichen planus and oral lichenoid lesions

Introduction: Oral Lichen Planus (OLP) and Oral Lichenoid Lesions (OLLs) are clinically and histopathologically similar lesions but with different etiologies and treatment plan, thus differentiating these two has been the center of many researches. Studies in different populations have been performed on clinical and histopathologic features of OLP and OLLs. Thus aim of the present study was to evaluate and also compare the clinical and histopathologic features of these two diseases in a 10‑year period in Esfahan. Materials and Methods: This descriptive–analytic study was based on retrospective survey of 232 records with clinical and histopathologic diagnosis of OLP and OLLs available from archive of oral pathology, Esfahan dental school 2000-2010. Data was statistically analyzed by use of independent t‑test, Fisher exact, and Chi‑square. Results: Involvement of lip was the only clinically significant difference between OLP and OLLs, most seen in OLLs. Band‑like inflammatory infiltrate mainly composed of lymphocyte, saw toothed rete ridges, Max Joseph space, and atrophic epithelium was significantly seen in OLP. While hyperkeratosis, deep connective tissue infiltrate composed of eosinophil, neutrophil, and plasma cell were seen in OLLs. Conclusion: Involvement of lip was the only clinically significant difference between OLP and OLLs. Histopathologically strict band like infiltration, atrophic epithelium, saw toothed rete ridges, and Max Joseph space are reliable criteria for differentiation of OLP as deep connective tissue infiltration and hyperparakeratosis are for diagnosis of OLLs.