title: Evaluation of biocompatibility of sodium perborate and 30% hydrogen peroxide using the analysis of the adherence capacity and morphology of macrophages.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the biocompatibility of the most used bleaching materials for pulpless teeth, sodium perborate and 30% hydrogen peroxide, in an experimental model of macrophages, through analysis of the adherence index and the cellular morphology.
  
  
  METHODS
  Inflammatory macrophages were obtained from peritoneal washed of Wistar rats. The evaluation of the adherence capacity of these cells to the plastic surface was conducted in Eppendorf tubes containing RPMI, after treatment with the bleaching agents diluted in 1:10, 1:100 and 1:1000 for 15 and 30 min, and incubation at 37 degrees C and humidified atmosphere of 5% CO(2) in air. The cellular morphology was verified after incubation of the cells treated with the bleaching agents in culture plaques and compared with normal cells in culture medium.
  
  
  RESULTS
  Results showed that sodium perborate neither increased the adherence index, nor altered the cellular morphology when compared to the control group. The distribution, cellular morphology, cytoplasmatic and nuclear characteristics, reproduced the aspects observed in normal macrophages. However, the treatment with 30% hydrogen peroxide presented an increase in adherence index when compared to the control group (RPMI), in all dilutions, according to Mann-Whitney test (n=08 and p=0.001 for dilutions 1:10 and 1:100, and n=08 and p=0.004 for dilution 1:1000). The morphology of the cells treated with this product presented structural alterations proportionally greater, depending on the dilution of this bleaching agent, and even in the highest dilution (1:1000) the cells presented very evident alterations.
  
  
  CONCLUSIONS
  This irreversible cellular damage as well as the elevation of the adherence index, characterizes the aggressive potential of 30% hydrogen peroxide, regardless of its dilution. Sodium perborate, on the other hand, showed biocompatibitity, since, no morphological nor functional alteration was observed in macrophages.
authors.affiliation: Departamento do Odontologia Restauradora, Faculdade de Odontologia de Pernambuco, Universidade de Pernambuco, Av. Gen. Newton Cavalcanti, 1650, 54753-220 Camaragibe, Pernambuco, Brazil. kka@hotlink.com
authors.forename: Kattyenne Kabbaz
authors.initials: KK
authors.lastname: Asfora
authors.forename: Maria do Carmo Moreira da Silva
authors.initials: Mdo C
authors.lastname: Santos
authors.forename: Marcos Antonio Japiassú Resende
authors.initials: MA
authors.lastname: Montes
authors.forename: Célia Maria Machado Barbosa
authors.initials: CM
authors.lastname: de Castro
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000008:administration & dosage / Q000494:pharmacology*; D001881:Borates / Q000008:administration & dosage / Q000494:pharmacology*; D002448:Cell Adhesion / Q000187:drug effects; D002467:Cell Nucleus / Q000187:drug effects; D002478:Cells, Cultured; D003593:Cytoplasm / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006861:Hydrogen Peroxide / Q000008:administration & dosage / Q000494:pharmacology*; D017737:Macrophages, Peritoneal / Q000166:cytology / Q000187:drug effects*; D008297:Male; D016877:Oxidants / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D014073:Tooth Bleaching
chemical_list: D001672:Biocompatible Materials; D001881:Borates; D016877:Oxidants; D006861:Hydrogen Peroxide; C027707:sodium perborate