Use of the Fractal Dimension to Differentiate Epithelium and Connective Tissue in Oral Leukoplakias

Abstract

Background: Oral leukoplakia (OL) is considered one of the most common potentially malignant oral disorders (OPMD), with a verified increased risk of developing oral cancer. The identification of the dysplasia grade (low-high) is the only consolidated factor used to evaluate this risk. The objective of this study was to verify the role of the fractal dimension (FD) in assessing this dysplasia. Methods: To begin, 29 OL and 10 normal oral mucosa (NOM) biopsies were retrieved for FD analysis of the epithelial (dime) and the connective (dimc) tissue. Results: In the OL group, the median value of dime is higher (1.67, IQR = 0.12) than for the NOM group (1.56, IQR = 0.08), with statistically significant differences (Wilcoxon test, p = 0.0031). There were no differences in relation to dimc. Significant differences were observed between the non-dysplasia vs. high-grade (p = 0.0156) and low-grade vs. high-grade (p = 0.0049) groups. No significant differences were identified in relation to dimc for the different degrees of dysplasia. For a cut-off point of 1.44 of dime, a specificity of 96.6% was obtained, a sensitivity of 100%, and an AUC = 0.819 (p = 0.003). Conclusions: FD at the level of the epithelium may be used as a diagnostic tool in OL.