Clinical and immunohistochemical characteristics of mucoceles.

BACKGROUND Mucoceles have diverse clinical and histological features. Their pathogenesis remains to be elucidated. OBJECTIVE To determine the structural and/or pathogenic differences between two clinically different types of mucoceles. METHODS Seventeen oral mucoceles were examined clinically and immunohistologically. The mucoceles were divided into two groups by their clinical manifestations: papular group (PG) and nodular group (NG). RESULTS Histologically, granulation tissue formed more frequently in the NG group, while CD4 and CD8 positive cells were more abundant in the PG group. There were no significant differences in the tumor necrosis factor-alpha or the matrix metalloproteinases (MMP)-2 and 9, between the two groups. CONCLUSION There were significant differences in the depth of the lesions, granulation tissue formation and infiltrating T lymphocytes between the PG and NP type of mucoceles. These findings suggest that the clinical manifestations may be influenced by the type of inflammatory response and extracellular matrix remodeling.