Squamous cell carcinoma (SCC) is the most common malignant lesion of the oral cavity. One important diagnostic problem involves differentiating histopathologically between SCC and pseudo-epitheliomatous hyperplasia (PEH) of the covering epithelium present in granular cell tumour (GCT) (a benign tumour), mimicking the invasive patterns of SCC. The complexity of the epithelial connective tissue interface (ECTI) in 84 profiles from normal oral mucosa, SCC and GCT-PEH cases was analyzed using both global and local fractal dimensions. Segmentation of the epithelial compartments into theoretical cell areas was performed using a space partition procedure and the morphological properties of these "cells" were analyzed. The complexity of the GCT-PEH ECTI profiles was marginally but significantly higher than that of SCC, which was significantly higher than normal ECTI profiles. The combined fractal and cell morphology data allowed up to 100%, and 96% correct discrimination between SCC and normal oral mucosa and between SCC and GCT-PEH respectively. In conclusion, we found that the architectural features of SCC, normal oral mucosa and GCT-PEH show differences that, when quantified, could be used for aiding in the diagnostic process.