FRACTAL DIMENSIONS OF THE EPITHELIAL CONNECTIVE-TISSUE INTERFACES IN PREMALIGNANT AND MALIGNANT EPITHELIAL LESIONS OF THE FLOOR OF THE MOUTH

Irregularity of the shape of epithelial-connective tissue interfaces i s a well-recognized feature of malignant and premalignant epithelial l esions, yet few attempts have been made to assess it objectively. The fractal dimension (as a measure of irregularity of shape) of the epith elial-connective tissue interface of premalignant, malignant and norma l epithelial tissues of the floor of the mouth was measured using box counting and boundary trace methods. The lowest value found was 0.99 ( a normal mucosa using the box method) and the highest 1.61 (a carcinom a using the trace method). Analysis of the values against the histopat hologic diagnoses (normal, keratosis with mild dysplasia, keratosis wi th moderate/severe dysplasia and squamous cell carcinoma) showed no si gnificant difference between normal epithelium and that from keratosis with mild dysplasia, but these were significantly different from the two other diagnoses, which were significantly different from each othe r. The study illustrated the potential of fractal analysis for providi ng objective diagnostic information about irregular shapes in histopat hology.