患儿，男，8岁，因左上前牙区出现膨隆4月余就诊。膨隆渐大，无疼痛、溃破、出血，压之疼痛，曾口服抗生素无效。体检：左上唇膨胀，日内十’处齿龈膨胀，界尚清，有压痛，似有乒乓球感，直径Icm左右，跨侧无异常。辅助检查：牙片示个根尖阴影，有致密白线，但未显示全貌。因条 Children, male, 8 years old, due to bulging left upper anterior teeth more than 4 months treatment. Bulging, no pain, ulceration, bleeding, pain pressure, oral antibiotics have been ineffective. Physical examination: upper left lip swelling, ten days at the gingival expansion, the sector is still clear, there are tenderness, it seems a sense of ping-pong, the diameter of about Icm, no abnormality across the cross. Auxiliary examination: tooth shows a pointed shadow, dense white line, but did not show the whole picture. Due to the article