Oral squamous cell carcinoma misinterpreted as reaction to chronic mechanical trauma: report of two cases and critical review of the literature.

Traumatic and reactive lesions of the oral mucosa, caused unintentionally by mechanical, thermal, or chemical irritation, may develop either acutely or chronically. In most cases, traumatic ulcerations heal within two weeks once the causative irritant is removed. However, persistent irritation can lead to chronic hyperkeratosis or mimic oral potentially malignant disorders (OPMDs). According to the World Health Organization (WHO), OPMDs such as leukoplakia, erythroplakia, proliferative verrucous leukoplakia, and oral submucous fibrosis carry an increased risk of malignant transformation into oral squamous cell carcinoma (OSCC). Clinically, reactive and potentially malignant lesions often present with overlapping features, rendering biopsy with histopathological evaluation essential for accurate diagnosis. This article presents two clinical cases that were initially misdiagnosed as lesions resulting from chronic mechanical trauma (CMT). Histopathological examination revealed high-grade epithelial dysplasia (carcinoma in situ) in one patient and a moderately differentiated OSCC in the other. These cases highlight the importance of a structured diagnostic approach—including removal of mechanical irritants, histopathological assessment, and regular clinical follow-up—to ensure early detection and appropriate management of suspicious lesions of the oral mucosa.