Unusual denture-associated oral squamous papilloma with koilocytosis: a case report and literature review

Background: Oral squamous papilloma (OSP) is a benign epithelial proliferation commonly linked to human papillomavirus (HPV) and usually affects the palate, tongue and lips. Anterior mandibular alveolar mucosa involvement is uncommon, and overlap between koilocytic HPV-suggestive change and chronic denture-related trauma is rarely documented. A review of the literature indicates limited documentation of such overlapping clinicopathological features at this anatomical site. Case presentation: A 49-year-old non-smoking male with absence of alcohol consumption history, presented with a 12-month painless, slowly enlarging papillary mass on the anterior mandibular alveolar mucosa beneath a poorly maintained removable denture. Intra-oral examination showed firm papillary folds of near-normal color and an adjacent traumatic ulcer at the denture-contact point. Excisional biopsy showed hyperplastic stratified squamous epithelium forming fingerlike papillary projections over narrow fibrovascular cores, with parakeratosis, basilar hyperplasia, regular mitotic activity, koilocytes in the spinous layer, and chronic lymphocytic stromal inflammation, with absence of dysplasia or invasion was confirmed. The diagnosis was squamous papilloma with koilocytic change suggestive of HPV cytopathic effect and chronic denture-associated inflammation. These findings supported a diagnosis of squamous papilloma with HPV-suggestive cytopathic effect in the setting of chronic denture-associated irritation. Management and outcomes: The lesion was completely excised, followed by denture adjustment and reinforcement of oral hygiene measures. Healing was uneventful at one-month review; longer-term follow-up is ongoing. Conclusions: This case highlights a rare oral squamous papilloma at an atypical mandibular alveolar site, demonstrating overlapping reactive denture-induced and HPV-associated epithelial changes. Histopathological evaluation, particularly koilocyte identification, is essential for diagnosis. Supported by the literature, this case underscores that chronic denture irritation does not preclude an HPV-related etiology, and clinicians should maintain a broad differential for papillary lesions at prosthesis-bearing sites.