Oral vegetable granuloma: ultrastructural and histological study

An unusual giant‐cell granulomatous inflammatory oral lesion is characterised by the presence of hyaline rings and by a lack of agreement on their nature, opinions ranging from their being hyaline degenerative blood‐vessels to remains of leguminous cells. Ten such lesions and a variety of vegetables have been examined in the present investigation. Light‐microscopical examination of the lesions revealed the hyaline rings surrounded by inflamed granulation tissue with associated multinuclear giant cells. Electron‐microscopical examination showed them to consist of a material similar to that of vegetable cell walls, sometimes with an associated superficial layer of collagen. The observations indicate that the lesions consist of vegetable remains with an associated foreign‐body type of inflammatory response.