Histologically, cases were pigmented nuvus on the oral mucosa (8 cases with nevocellular nevus and cases with the com组织学观察，该组病例中口腔粘膜色素痣例（痣细胞痣8例，普通蓝痣 例），交界变例，口腔粘膜单纯雀斑样痣例，口腔黑斑 例。