title: Immunohistochemical analysis of Ki-67 in dental follicle of asymptomatic impacted third molars.
abstract: BACKGROUND
  Dental follicle (DF) is an ectomesenchymal tissue that surrounds the developing tooth germ and contains precursor cells for cementoblasts, periodontal ligaments and osteoblasts. Radiographically, the DFs are seen as semicircular radiolucencies around unerupted teeth. However, if the DFs are larger than 2.5 mm, they are considered to be a pathological change.
  
  
  OBJECTIVE
  The purpose of this study is to assess the cell proliferation activity of DF surrounding an asymptomatic impacted third molar teeth using the Ki 67 proliferation marker and to evaluate the variation of cell proliferation depending on the age factor.
  
  
  METHODS
  Forty-four specimens of DFs associated with impacted mandibular third molars fully covered by mucosa or bone were surgically removed from 44 patients. The patients were divided into 2 age groups. Twenty of forty-four DFs were between 18 and 29 years (Group 1) and 24 were 30 years and above (Group 2). Ki-67 immunostaining was evaluated in epithelial component of the DFs.
  
  
  RESULTS
  Ki 67 expression was found to be 60% in Group 1 and 75% in Group 2. Statistically significant differences were found among the two groups in both the basal layer and the supra-basal layer.
  
  
  CONCLUSIONS
  This study shows that DFs have more proliferative potential in older people as compared to the young and squamous metaplasia may be an early sign of developing lesions of odontogenic origin. Therefore, clinicians should be aware that histopathological changes could be found in DFs without clinical and radiographic alterations.
authors.affiliation: Department of Oral and Maxilofacial Surgery, Faculty of Dentistry, Selcuk University, Konya, Turkey.
authors.forename: Hasan
authors.initials: H
authors.lastname: Kucukkolbasi
authors.affiliation: Department of Oral and Maxilofacial Surgery, Necmettin Erbakan University, Konya, Turkey.
authors.forename: Alparslan
authors.initials: A
authors.lastname: Esen
authors.affiliation: Department of Pathology, Medical Faculty, Baskent University, Konya, Turkey.
authors.forename: Ozgur Hilal
authors.initials: OH
authors.lastname: Erinanc
keywords: Cell proliferation; Dental follicle; Ki-67