title: Effect of different methods of polymerizing ocular prosthesis acrylic resin on a human conjunctival cell line.
abstract: BACKGROUND
  Ocular prosthesis acrylic resins should be biocompatible regardless of the polymerization method. The authors are unaware of a study that evaluated the biocompatibility of ocular prostheses.
  
  
  OBJECTIVE
  The purpose of this in vitro study was to evaluate the cytotoxicity of different methods of polymerizing ocular prosthesis acrylic resin. This was accomplished by analyzing the cell proliferation, production of proinflammatory cytokines, and expression of extracellular matrix proteins related to tissue remodeling and repair of a human conjunctival cell line.
  
  
  METHODS
  Nine acrylic resin specimens were divided into 3 groups: polymerization in a water bath, by microwave, or by autopolymerization. Eluates (prepared for 72 hours) were exposed to cells for 72 hours. A medium without specimens served as negative control (nonstimulated group). The tetrazolium dye MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay was performed to evaluate the cytotoxic effect, and an enzyme-linked immunosorbent assay was executed for analysis of interleukin 1 β (IL1β), IL6, tumor necrosis factor α (TNFα), and CCL3/MIP1α production. Also, real-time reverse transcriptase (RT)-PCR was performed for analysis of mRNA expression of type IV collagen (COL IV), TGFβ, and MMP9, and data were tested using ANOVA with Bonferroni post hoc test (α=.05).
  
  
  RESULTS
  Microwave-processed resin showed slight cytotoxicity due to a significant reduction in cell proliferation and an increase in IL6 quantity. Higher levels of mRNA expression of COL IV, MMP9, and TGFβ were verified in water bath-processed resin, which were similar to those in the nonstimulated group.
  
  
  CONCLUSIONS
  Microwave-processed resin showed a significant reduction in cell proliferation and an increase in IL6 quantity. Heat-polymerized resin exhibited a higher mRNA expression of COL IV, MMP9, and TGFβ; this result was similar to that in the nonstimulated group.
authors.affiliation: Postgraduate student, Department of Dental Materials and Prosthodontics, Aracatuba Dental School, São Paulo State University, São Paulo, Brazil.
authors.forename: Emily Vivianne Freitas
authors.initials: EV
authors.lastname: da Silva
authors.affiliation: Professor, Department of Dental Materials and Prosthodontics, Aracatuba Dental School, São Paulo State University, São Paulo, Brazil. Electronic address: goiato@foa.unesp.br.
authors.forename: Marcelo Coelho
authors.initials: MC
authors.lastname: Goiato
authors.affiliation: Professor, Department of Dental Materials and Prosthodontics, Aracatuba Dental School, São Paulo State University, São Paulo, Brazil.
authors.forename: Daniela Micheline
authors.initials: DM
authors.lastname: Dos Santos
authors.affiliation: Postgraduate student, Department of Dental Materials and Prosthodontics, Aracatuba Dental School, São Paulo State University, São Paulo, Brazil.
authors.forename: Liliane da Rocha
authors.initials: LD
authors.lastname: Bonatto
authors.affiliation: Graduate student, Department of Basic Sciences, Aracatuba Dental School, São Paulo State University, São Paulo, Brazil.
authors.forename: Victor Gustavo Balera
authors.initials: VG
authors.lastname: Brito
authors.affiliation: Professor, Department of Basic Sciences, Aracatuba Dental School, São Paulo State University, São Paulo, Brazil.
authors.forename: Sandra Helena Penha
authors.initials: SH
authors.lastname: de Oliveira
mesh_terms: D000180:Acrylic Resins; D002460:Cell Line; D003228:Conjunctiva / Q000166:cytology; D003819:Denture Bases; D005137:Eye, Artificial; D006801:Humans; D008422:Materials Testing; D058105:Polymerization
chemical_list: D000180:Acrylic Resins