Clinical and histopathological evaluation of collagen fiber orientation in patients with oral submucous fibrosis

BACKGROUND: Oral submucous fibrosis is a chronic debilitating disease of oral mucosa and is characterized by generalized fibrosis of the oral soft tissues which tends to present itself clinically as palpable vertical fibrous bands. Hence, this study was conducted to evaluate histopathologically the collagen fiber bundle orientation in relation to epithelium and to find the reason for unidirectional orientation of clinically palpable fibrous bands. MATERIALS AND METHODS: The study included 33 cases of oral submucous fibrosis and 8 cases of normal tissue. RESULTS: Histologically most of the collagen fibers were parallel to the epithelium, and there was a statistically significant difference in orientation between oral submucous fibrosis and control groups in both buccal mucosa and labial mucosa. CONCLUSION: The reason for unidirectional alignment of clinical fibrous bands could be due to chronic stimulation of oral mucosa by the irritants leading to change in the orientation of collagen fiber bundles, which might result in scar formation similar to that of wound healing, where the collagen fibers are oriented parallel to the epidermis.