title: Rare periodontal ligament drainage for periapical inflammation of an adjacent tooth: a case report and review of the literature.
abstract: Aim. To report a case with an unusual drainage route of periapical inflammation exiting through the gingival sulcus of an adjacent vital tooth and review probable factors determining the diversity of the discharge routes of periapical inflammation. Summary. An 18-year-old male patient presented with periodontal abscess of tooth 46, which was found to be caused by a periapical cyst with an acute abscess of tooth 45. During endodontic surgery, a rarely reported drainage route for periapical inflammation via the gingival sulcus of an adjacent vital tooth was observed for the first time. Complete periodontal healing of the deep pocket of tooth 46 and hiding of the periapical cyst of tooth 45 followed after root canal treatment and periapical surgery with Bio-Oss Collagen implantation on tooth 45. The drainage routes of periapical inflammation are multivariate and the diversity of drainage pathways of periapical inflammation is mainly related to factors such as gravity, barriers against inflammation, and the causative tooth itself.
authors.affiliation: Department of Periodontology, School of Stomatology, Shandong University, 44-1 Wenhuaxi Road, Shandong Province, Jinan 250012, China.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Guo
authors.affiliation: Department of Periodontology, School of Stomatology, Shandong University, 44-1 Wenhuaxi Road, Shandong Province, Jinan 250012, China ; Key Laboratory of Oral Biomedicine of Shandong Province, School of Stomatology, Shandong University, Jinan 250012, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Lu
authors.affiliation: Department of Periodontology, School of Stomatology, Shandong University, 44-1 Wenhuaxi Road, Shandong Province, Jinan 250012, China ; Key Laboratory of Oral Biomedicine of Shandong Province, School of Stomatology, Shandong University, Jinan 250012, China.
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Han
authors.affiliation: Key Laboratory of Oral Biomedicine of Shandong Province, School of Stomatology, Shandong University, Jinan 250012, China.
authors.forename: Shubo
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Periodontology, School of Stomatology, Shandong University, 44-1 Wenhuaxi Road, Shandong Province, Jinan 250012, China ; Key Laboratory of Oral Biomedicine of Shandong Province, School of Stomatology, Shandong University, Jinan 250012, China.
authors.forename: Pishan
authors.initials: P
authors.lastname: Yang