Hahn W
MMW Munch Med Wochenschr. 1979 Nov 30;121(48):1605-7.
Extraoral fistulas, whether primary or as the residue of an abscess, have different causes. According to case reports in the literature and from clinical experience the dentogenous cause is the more frequent. For this reason a possible tooth involvement should be ruled out before therapy, loss of dental pulp of various origin and periodontal diseases should be excluded, otherwise the treatment must begin with the cause, after which further intervention is usually superfluous.
口外瘘管，无论是原发性的还是脓肿残留所致，其病因各不相同。根据文献中的病例报告以及临床经验，牙源性病因更为常见。因此，在治疗前应排除牙齿受累的可能，排除各种原因引起的牙髓丧失及牙周疾病，否则治疗必须从病因入手，之后通常无需进一步干预。
