Abstract
The authors report the rare case of a granular cell lesion of the gingiva overlying a maxillary incisor tooth that was delayed in eruption in a 9-year-old Japanese boy. The lesion was composed of a nodular aggregation of ovoid-shaped cells with eosinophilic and granular cytoplasm, which was immunohistochemically positive for LDL, CD68, HLA-DR, cathepsin D and heparanase. These cells were neither positive for S-100 protein, vimentin, desmin nor myosin. The results suggested that this lesion is a sort of xanthoma, but neither granular cell tumor nor congenital epulis. The etiology of this lesion is unknown, but it seems to be associated with tissue remodeling processes of the pericoronal mesenchymal tissue during tooth eruption. Such an unusual pericoronal tissue containing a xanthomatous lesion may be one of the causes for delay in tooth eruption.