男,20岁。因左侧上颌牙龈肿痛1年余,于1990年9月前来我科就诊。口腔检查:缺失,其牙槽嵴处有一约1.5cm长、0.5cm宽的暗黄色粗糙面暴露于口腔,无触痛,质地坚硬,不松动。颊侧及腭侧牙龈隆起,轻度水肿、充血,触之较硬,略有痛感。除缺失外均未见萌出,其它牙齿无异常。全身状态尚好,无外伤史,无传染病接触史。 Male, 20 years old. Due to the left maxillary gingivalgia more than 1 year, in September 1990 came to our department. Oral examination: missing, the alveolar ridge at about 1.5cm long, 0.5cm wide dark yellow rough surface exposed to the mouth, no tenderness, hard texture, not loose. Buccal and palatal gingival bulge, mild edema, congestion, the touches hard, a slight pain. Except for the absence of no outside eruption, no other teeth abnormalities. The body condition is still good, no history of trauma, no history of exposure to infectious diseases.