Dr. M. Vamsi Krishna

BACKGROUND Oral submucous fibrosis (OSF) is a potentially malignant disease that primarily affects any part of the oral cavity and sometimes the pharynx. The disease is chronic, insidious and progressive in nature. It causes mucosal rigidity resulting in discomfort, burning and limitation of opening of the mouth. Blanching of the oral mucosa is an important clinical feature seen in the early stage of OSF. The present study had been undertaken to correlate the clinical staging of mouth opening with histopathological grading in OSMF patients. We wanted to morphometrically quantify the histopathological changes in oral submucous fibrosis and to correlate them with grading and clinical severity of trismus. METHODS 78 patients diagnosed clinically were subjected to biopsy of the lesions from their periphery and compared with the normal areas. The criteria proposed by Pindborg and Sirsat (1966), who described four consecutive stages based upon sections stained with haematoxylin and eosin were used. The stages were classified as: 1) Very early stage: Characterized by fine collagen dispersed with marked oedema, prominent fibroelastic response dilated and congested blood vessels and inflammatory cells (mainly polymorphs and eosinophils). 2) Early stage: Early hyalinization in juxta epithelial area with thickened separate bundles of collagen and clumps of young fibroblasts in moderate number. 3) Moderately advanced stage: Moderately hyalinized collagen, the amorphous change starting from the juxta-epithelial basement membrane. RESULTS Among 78 patients with OSF, 57 were males (73.07%) and 21 were females (26.92%). Among them, histologically 19 (24.35%) were of very early stage, 27 (34.61%) of early stage and 22 (28.20%) of moderately advanced stage and 10 (12.82%) patients were in advanced stage. Collagenization was observed in 17/22 of moderately severe OSF and 10/10 of severely affected OSF. The thickness of the epithelium and subepithelial collagen showed no statistically significant differences between the different stages. However, blood vessel density was indirectly proportional to the histological stages. Histological stages directly correlated the frequency of trismus, but the severity of trismus showed no relation to the epithelial thickness or collagenization. CONCLUSIONS The thickness of the epithelium and subepithelial collagen should not be included in the histological staging criteria of oral submucous fibrosis. Probably the degree of hyalinization of collagen fibres and involvement of muscle fibres are more important in causing trismus, rather than a simple increase in the subepithelial collagen thickness.