患者:许×,10岁,4个月前因前牙疼痛伴有面部肿胀,4～5天后在当地行脓肿切开,以后留有瘘管,时有脓液流出,无外伤史。检查:(?)松动Ⅰ°,牙冠完整,未见龋坏,无创伤(牙合),腭侧近牙龈缘处有二块釉质突起,中间有纵形沟裂,沟延至牙周袋,深约8mm,根尖处有一瘘管,探之有脓溢出。诊断:(?)牙内陷诱发牙周病并发慢性根尖周炎伴 Patients: Xu ×, 10 years old, 4 months ago facial pain accompanied by facial swelling, abercrombie, 4 to 5 days after the local abscess incision, after leaving a fistula, when pus outflow, no history of trauma. Check: (?) Loosen Ⅰ °, the crown is complete, no caries, no trauma (occlusion), near the gingival margin of the palatal there are two enamel protrusions, the middle longitudinal cleft rupture, ditch to the periodontal pocket, About 8mm deep, there is a fistula at the apical, exploration of the purulent overflow. Diagnosis: (?) Dental retraction induced periodontal disease complicated with chronic apical periodontitis