title: Expansive focal cemento-osseous dysplasia.
abstract: OBJECTIVE
  To present a case of expansive focal cemento-osseous dysplasia and emphasize the importance of differential diagnosis.
  
  
  BACKGROUND
  Cemento-osseous dysplasia is categorized into three subtypes on the basis of the clinical and radiographic features: Periapical, focal and florid. The focal type exhibits a single site of involvement in any tooth-bearing or edentulous area of the jaws. These lesions are usually asymptomatic; therefore, they are frequently diagnosed incidentally during routine radiographic examinations. Lesions are usually benign, show limited growth, and do not require further surgical intervention, but periodic follow-up is recommended because occasionally, this type of dysplasia progresses into florid osseous dysplasia and simple bone cysts are formed.
  
  
  METHODS
  A 24-year-old female patient was referred to our clinic for swelling in the left edentulous mandibular premolarmolar region and felt discomfort when she wore her prosthetics. She had no pain, tenderness or paresthesia. Clinical examination showed that the swelling in the posterior mandible that was firm, nonfluctuant and covered by normal mucosa. On panoramic radiography and computed tomography, a well defined lesion of approximately 1.5 cm in diameter of mixed density was observed. The swelling increased slightly in size over 2 years making it difficult to use prosthetics and, therefore, the lesion was totally excised under local anesthesia, and surgical specimens were submitted for histopathological examination. The histopathological diagnosis was focal cemento-osseous dysplasia.
  
  
  CONCLUSIONS
  In the present case, because of the increasing size of the swelling making it difficult to use prosthetics, young age of the patient and localization of the lesion, in the initial examination, cemento-ossifying fibroma was suspected, and the lesion was excised surgically; the histopathological diagnosis confirmed it as focal cemento-osseous dysplasia.
  
  
  CONCLUSIONS
  We present a case of expansive focal cemento-osseous dysplasia. Differential diagnosis is essential because ossifying fibroma is a real neoplastic entity.
authors.affiliation: Department of Maxillofacial Surgery, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Emel Uzun
authors.initials: EU
authors.lastname: Bulut
authors.forename: Aydan
authors.initials: A
authors.lastname: Acikgoz
authors.forename: Bora
authors.initials: B
authors.lastname: Ozan
authors.forename: Ayse Zeynep
authors.initials: AZ
authors.lastname: Zengin
authors.forename: Omer
authors.initials: O
authors.lastname: Gunhan
mesh_terms: D002485:Cementoma / Q000175:diagnosis*; D003475:Curettage; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008339:Mandibular Neoplasms / Q000175:diagnosis*; D011862:Radiography, Panoramic; D014057:Tomography, X-Ray Computed; D055815:Young Adult