title: Keratocystic odontogenic tumor arising at the mandibular ramus with an impacted tooth: a case report and mimic lesions.
abstract: OBJECTIVE
  To consider the biologic behaviors of keratocystic odontogenic tumors (KCOTs) and ameloblastomas and dentigerous cysts.
  
  
  METHODS
  A 63-year-old Japanese man presented with swelling and discomfort in the left cheek during jaw movement. Examination revealed a multilocular lesion within the mandible extending from the left second premolar to the left mandibular ramus and coronoid process; the lesion contained a deviated impacted tooth. The tumor had expanded beyond the bone and was invading the masseter and medial pterygoid muscles. Marginal mandibulectomy with a free iliac bone graft was performed.
  
  
  RESULTS
  No recurrence was observed during a 7-year follow-up.
  
  
  CONCLUSIONS
  The histopathological diagnosis of the lesion showed it was a KCOT. These tumors usually grow within the bone, causing bone expansion. However, this tumor had expanded beyond the bone and invaded surrounding muscles. Thus, KCOTs can, in rare cases, manifest themselves as described here. Evaluating preoperative images and histopathological findings is important to determine the optimal treatment strategy.
authors.affiliation: a Division of Dentistry and Oral Surgery, Department of Sensory and Locomotor Medicine, Faculty of Medical Sciences, University of Fukui , 23-3 Shimoaizuki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui 910-1193, Japan .
authors.forename: Takashi
authors.initials: T
authors.lastname: Kimura
authors.forename: Seigo
authors.initials: S
authors.lastname: Ohba
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Yoshimura
authors.forename: Shuichi
authors.initials: S
authors.lastname: Fujita
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Imamura
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Kitagawa
authors.forename: Kazuo
authors.initials: K
authors.lastname: Sano
mesh_terms: D000273:Adipose Tissue / Q000000981:diagnostic imaging / Q000473:pathology; D000564:Ameloblastoma / Q000473:pathology; D044466:Asian People; D001641:Bicuspid / Q000473:pathology; D016025:Bone Transplantation; D002610:Cheek; D003803:Dentigerous Cyst / Q000473:pathology; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D008339:Mandibular Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D063168:Mandibular Osteotomy / Q000379:methods; D008406:Masseter Muscle / Q000473:pathology; D008875:Middle Aged; D009807:Odontogenic Cysts / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D009808:Odontogenic Tumors / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D011626:Pterygoid Muscles / Q000473:pathology; D014057:Tomography, X-Ray Computed; D014095:Tooth, Impacted / Q000473:pathology*
keywords: Ameloblastoma; Dentigerous cyst; Impacted tooth; Keratocystic odontogenic tumor; Mandibular ramus