title: Effect of chemical disinfection and accelerated aging on color stability of maxillofacial silicone with opacifiers.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the color stability of MDX4-4210 maxillofacial elastomer with opacifier addition submitted to chemical disinfection and accelerated aging.
  
  
  METHODS
  Ninety specimens were obtained from Silastic MDX4-4210 silicone. The specimens were divided into three groups (n = 30): Group I: colorless, Group II: barium sulfate opacifier, Group III: titanium dioxide opacifier. Specimens of each group (n = 10) were disinfected with effervescent tablets, neutral soap, or 4% chlorhexidine gluconate. Disinfection was conducted three times a week for 2 months. Afterward, the specimens were submitted to different periods of accelerated aging. Color evaluation was carried out after 60 days (disinfection period) and after 252, 504, and 1008 hours of accelerated aging, using a reflection spectrophotometer. Color alterations were calculated by the CIE L*a*b* system. Data were analyzed by three-way ANOVA and Tukey test (α= 0.05).
  
  
  RESULTS
  Group II exhibited the lowest color change, whereas Group III the highest (p < 0.05), regardless of the chemical disinfection and accelerated aging periods.
  
  
  CONCLUSIONS
  Opacifier addition, chemical disinfection, and accelerated aging procedures affected the color stability of the maxillofacial silicone.
authors: Department of Dental Material and Prosthodontics, Faculty of Dentistry of Araçatuba, UNESP-Univ Estadual Paulista, Brazil. goiato@foa.unesp.br
authors: Marcelo Coelho
authors: MC
authors: Goiato
authors: Marcela Filié
authors: MF
authors: Haddad
authors: Aldiéris Alves
authors: AA
authors: Pesqueira
authors: Amália
authors: A
authors: Moreno
authors: Daniela Micheline
authors: DM
authors: Dos Santos
authors: Lisiane Cristina
authors: LC
authors: Bannwart
mesh_terms: D001466:Barium Sulfate; D003116:Color; D003287:Contrast Media; D004129:Dimethylpolysiloxanes; D004202:Disinfectants / Q000737:chemistry; D004203:Disinfection / Q000379:methods; D008422:Materials Testing; D008447:Maxillofacial Prosthesis; D017797:Prosthesis Coloring; D012826:Silicone Elastomers; D013056:Spectrophotometry, Ultraviolet; D013997:Time Factors; D014025:Titanium
chemical_list: D003287:Contrast Media; D004129:Dimethylpolysiloxanes; D004202:Disinfectants; C020964:MDX 4-4210; D012826:Silicone Elastomers; C009495:titanium dioxide; D001466:Barium Sulfate; D014025:Titanium