title: Jaw cysts diagnosed in an Italian population over a 20-year period.
abstract: BACKGROUND
  Cysts of the jaws (JCs) are an important topic of oral pathology, but few epidemiological data are present in the literature, in particular about the potential of recurrence. The aim of this study was to describe a case series of JCs from a single institution, evaluating the frequency, the site, the age distribution, and the percentage of recurrence of all types of JCs.
  
  
  METHODS
  All JCs present in the histological records of the Section of Anatomic Pathology of the University of Bologna at Bellaria Hospital from 1992 to 2012 were retrieved.
  
  
  RESULTS
  A total of 1136 jaws cysts were obtained, of which 1117 (98.3%) were odontogenic and 19 (1.7%) were nonodontogenic. About odontogenic cysts (OCs), the most frequent was the radicular cyst (538 cases), followed by parakeratinized keratocystic odontogenic tumor (pKOT, 193 cases) and dentigerous cyst (120 cases). Among pKOT, 21 out of 193 cases (10.89%) showed a recurrence after a mean time of 4.5 years (range, 1-12 years). During follow-up (mean 11 years, range 1-19 years), all 3 cases of botrioid cysts, 12 out of 46 cases of unicystic ameloblastoma (26.09%), 2 out of 20 cases of calcifying OCs (10%) and 2 out of 538 cases of radicular cyst (0.37%) showed a recurrence.
  
  
  CONCLUSIONS
  Our study confirms that the distribution pattern of JCs in Italy is relatively similar to other studies worldwide and emphasizes the importance of recognizing the different histological types of JCs for their potential local aggressive behavior.
authors.affiliation: Bellaria Hospital, University of Bologna, Bologna, Italy giacomo.delcorso@unibo.it.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Del Corso
authors.affiliation: Rizzoli Hospital, Bologna, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Righi
authors.affiliation: Bellaria Hospital, University of Bologna, Bologna, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Bombardi
authors.affiliation: Bellaria Hospital, University of Bologna, Bologna, Italy.
authors.forename: B
authors.initials: B
authors.lastname: Rossi
authors.affiliation: Bellaria Hospital, University of Bologna, Bologna, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Dallera
authors.affiliation: Bellaria Hospital, University of Bologna, Bologna, Italy.
authors.forename: G A
authors.initials: GA
authors.lastname: Pelliccioni
authors.affiliation: Policlinico S. Orsola, University of Bologna, Bologna, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Marchetti
authors.affiliation: Bellaria Hospital, University of Bologna, Bologna, Italy.
authors.forename: M P
authors.initials: MP
authors.lastname: Foschini
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007558:Italy; D007570:Jaw Cysts / Q000453:epidemiology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009807:Odontogenic Cysts / Q000453:epidemiology* / Q000473:pathology; D015995:Prevalence; D012008:Recurrence; D012189:Retrospective Studies; D055815:Young Adult
keywords: jaw cysts; keratocystic odontogenic tumors; odontogenic tumors