Pyogenic granuloma is one of the inflammatory hyperplasias seen in the oral cavity. This term is a misnomer because the lesion is unrelated to infection and in reality arises in response to various stimuli such as low-grade local irritation, traumatic injury or hormonal factors. It predominantly occurs in the second decade of life in young females, possibly because of the vascular effects of female hormones. Clinically, oral pyogenic granuloma is a smooth or lobulated exophytic lesion manifesting as small, red erythematous papules on a pedunculated or sometimes sessile base, which is usually hemorrhagic. The surface ranges from pink to red to purple, depending on the age of the lesion. Although excisional surgery is the treatment of choice for it, some other treatment protocols such as the use of Nd:YAG laser, flash lamp pulsed dye laser, cryosurgery, intralesional injection of ethanol or corticosteroid and sodium tetradecyl sulfate sclerotherapy have been proposed. Because of the high frequency of pyogenic granuloma in the oral cavity, especially during pregnancy, and necessity for proper diagnosis and treatment, a complete review of published information and investigations about this lesion, in addition to knowledge about new approaches for its treatment is presented.

Pyogenic granuloma of the oral cavity: comparative study of its clinicopathological and immunohistochemical features. Pathol Int. 2005 Jul;55(7):391-7.

There are two histological types of pyogenic granuloma (PG) of the oral cavity: the lobular capillary hemangioma (LCH) and non-LCH type. The aim of the present study was to examine and compare the clinical features, etiological factors, diameter of vascular elements and immunohistochemical features of LCH and non-LCH histological types of PG to determine whether they are two distinct entities. Thirty cases of LCH and 26 cases of non-LCH PG were retrieved and retrospectively studied. Clinically, LCH PG occurred more frequently (66.4%) as sessile lesion whereas non-LCH PG occurred as pedunculated (77%). Non-LCH PG was associated more frequently (86.4%) with etiological factors. The lobular area of the LCH PG contained a greater number of blood vessels with small luminal diameter than did the central area of non-LCH PG. In the central area of non-LCH PG a significantly greater number of vessels with perivascular mesenchymal cells non-reactive for alpha-smooth muscle actin and muscle-specific actin was present than in the lobular area of LCH PG. The differences found in the present study suggest that the two histological types of PG represent distinct entities.