title: Lateral periodontal cyst: a case report and literature review.
abstract: BACKGROUND
  The lateral periodontal cyst is considered a developmental odontogenic cyst with unusual occurrence. In most cases it is preliminary diagnosed as a radiographic finding, presenting as well circumscribed or as a round or teardrop-shaped radiolucent area. Due to its location it can easily be misdiagnosed as a lesion of endodontic origin. Final diagnosis should be based on histopatological examination. The purpose of this paper is to report a classic case of lateral periodontal cyst located in the anterior region of mandible and to review the relevant literature which describes the clinical, radiological and histopathological features of lateral periodontal cysts.
  
  
  METHODS
  A 50 years female patient complained of an asymptomatic gingival swelling in the region between the left mandibular lateral incisor and canine. Radiographic examination revealed a well circumscribed radiolucency with approximately 0.5 cm diameter with a radiopaque margin between the roots of the left mandibular lateral incisor and canine. The adjacent teeth had vital pulp.
  
  
  RESULTS
  A total enucleation of the lesion was performed, and intraoperative examination showed a single lesion with no communication between the cyst's cavity and the oral environment. Histological examination revealed that the lesion was "lateral periodontal cyst of developmental origin". There was no recurrence or complications for 24 months follow-up.
  
  
  CONCLUSIONS
  The lateral periodontal cyst can be considered in the differential diagnosis when a radioloucent lesion appears adjacent to the roots of vital teeth. The treatment of choice is surgical removal and subsequent histological evaluation to confirm the diagnosis. Relapses are infrequent.
authors.affiliation: Postgraduation Program in Oral Biopathology, São José dos Campos Dental School, São Paulo State University - UNESP, São José dos Campos, São Paulo, Brazil and Postgraduation Program in Nanosciences and Advanced Materials, Federal University of ABC Santo André, São Paulo Brazil.
authors.forename: Luis Felipe das Chagas E Silva
authors.initials: LF
authors.lastname: de Carvalho
authors.affiliation: Postgraduation Program in Oral Biopathology, São José dos Campos Dental School, São Paulo State University - UNESP São José dos Campos, São Paulo Brazil.
authors.forename: Celina Faig
authors.initials: CF
authors.lastname: Lima
authors.affiliation: Department of Biosciences and Oral Diagnosis, São José dos Campos Dental School, São Paulo State University - UNESP São José dos Campos, São Paulo Brazil.
authors.forename: Luiz Antonio Guimarães
authors.initials: LA
authors.lastname: Cabral
authors.affiliation: Department of Biosciences and Oral Diagnosis, São José dos Campos Dental School, São Paulo State University - UNESP São José dos Campos, São Paulo Brazil.
authors.forename: Adriana Aigotti Haberbeck
authors.initials: AA
authors.lastname: Brandão
authors.affiliation: Department of Biosciences and Oral Diagnosis, São José dos Campos Dental School, São Paulo State University - UNESP São José dos Campos, São Paulo Brazil.
authors.forename: Janete Dias
authors.initials: JD
authors.lastname: Almeida
keywords: apical periodontal cyst; jaw cysts.; odontogenic cysts; radicular cyst