Oral hyaline ring granuloma.

Hyaline ring granuloma is a rare oral lesion with an unclear and controversial etiology, characterized by the presence of rings of palely eosinophilic structureless material (the so-called hyaline rings) with multinucleated giant cells around and within the very same rings.Various theories have been proposed about the pathogenesis of hyaline ring granulomas. Many authors consider a vegetable origin, suggesting that it may represent a reaction to foreign material such as food (and in particular pulses). Instead, other authors deny this possibility, proposing that the hyaline rings might represent degenerated blood vessels, degenerated collagen, or fibrosed extravasated serum proteins.The aim of this article is to present a case of hyaline ring granuloma and to briefly review the literature.