title: Immunohistochemical study of presence of T cells, B cells, and macrophages in periradicular lesions of primary teeth.
abstract: BACKGROUND
  The periapical lesion is the result of a local inflammatory reaction caused by bacteria and its products present on the root canal. The interaction between inflammatory cells and bacteria elicit both specific and non-specific immune responses.
  
  
  OBJECTIVE
  Due to the lack of studies evaluating the role of the immune system in periapical lesions of primary teeth and considering the potentially systemic effects that these infections can cause in children, especially because of the immaturity of their immune system, we sought to evaluate the presence of T cells, B cells and macrophages on periradicular lesions in primary teeth.
  
  
  METHODS
  14 periradicular lesions were analyzed. The immunohistochemistry technique was performed using CD45RO, CD20, CD68 monoclonal antibodies aiming to identify T cells, B cells and macrophages, respectively. Cells were quantified by microscopic analysis of histological sections.
  
  
  RESULTS
  Mean percentage of positive cells CD45RO was 11.76; CD20 was 5.25; CD68 was 10.92. Our results showed that T and B cells and macrophages comprise the majority of the inflammatory infiltrate.
  
  
  CONCLUSIONS
  We concluded that both humoral and cell mediated immune reactions take place in periradicular lesions of primary teeth. The immune system plays an important role on the periradicular inflammatory processes in primary teeth.
authors.affiliation: Department of Stomatology, Federal University of Santa Catarina, Brazil. michelebolan@hotmail.com
authors.forename: Michele
authors.initials: M
authors.lastname: Bolan
authors.forename: Daniele de Almeida
authors.initials: DA
authors.lastname: Lima
authors.forename: Cláudia Pinto
authors.initials: CP
authors.lastname: Figueiredo
authors.forename: Gabriella
authors.initials: G
authors.lastname: Di Giunta
authors.forename: Maria José de Carvalho
authors.initials: MJ
authors.lastname: Rocha