title: Sterilizing elastomeric chains without losing mechanical properties. Is it possible?
abstract: OBJECTIVE
  To investigate the effects of different sterilization/disinfection methods on the mechanical properties of orthodontic elastomeric chains.
  
  
  METHODS
  Segments of elastomeric chains with 5 links each were sent for sterilization by cobalt 60 (Co60) (20 KGy) gamma ray technology. After the procedure, the elastomeric chains were contaminated with clinical samples of Streptococcus mutans. Subsequently, the elastomeric chains were submitted to sterilization/disinfection tests carried out by means of different methods, forming six study groups, as follows: Group 1 (control - without contamination), Group 2 (70°GL alcohol), Group 3 (autoclave), Group 4 (ultraviolet), Group 5 (peracetic acid) and Group 6 (glutaraldehyde). After sterilization/disinfection, the effectiveness of these methods, by Colony forming units per mL (CFU/mL), and the mechanical properties of the material were assessed. Student's t-test was used to assess the number of CFUs while ANOVA and Tukey's test were used to assess elastic strength.
  
  
  RESULTS
  Ultraviolet treatment was not completely effective for sterilization. No loss of mechanical properties occurred with the use of the different sterilization methods (p > 0.05).
  
  
  CONCLUSIONS
  Biological control of elastomeric chains does not affect their mechanical properties.
authors.affiliation: Universidade Estadual do Sudoeste da Bahia, Jequié, Bahia, Brazil.
authors.forename: Matheus Melo
authors.initials: MM
authors.lastname: Pithon
authors.affiliation: Universidade Estadual do Sudoeste da Bahia, Jequié, Bahia, Brazil.
authors.forename: Caio Souza
authors.initials: CS
authors.lastname: Ferraz
authors.affiliation: Universidade Federal da Bahia, Vitória da Conquista, Bahia, Brazil.
authors.forename: Francine Cristina Silva
authors.initials: FC
authors.lastname: Rosa
authors.affiliation: Universidade Federal da Bahia, Vitória da Conquista, Bahia, Brazil.
authors.forename: Luciano Pereira
authors.initials: LP
authors.lastname: Rosa
mesh_terms: D058491:Bacterial Load / Q000187:drug effects / Q000528:radiation effects; D003037:Cobalt Radioisotopes / Q000627:therapeutic use; D019551:Dental Disinfectants / Q000627:therapeutic use; D003764:Dental Materials / Q000737:chemistry* / Q000528:radiation effects; D004203:Disinfection / Q000379:methods; D004548:Elasticity; D020724:Elastomers / Q000737:chemistry* / Q000528:radiation effects; D000431:Ethanol / Q000627:therapeutic use; D005720:Gamma Rays / Q000627:therapeutic use; D005976:Glutaral / Q000627:therapeutic use; D006358:Hot Temperature; D006801:Humans; D008422:Materials Testing; D009967:Orthodontic Appliances / Q000382:microbiology; D010463:Peracetic Acid / Q000627:therapeutic use; D019275:Radiopharmaceuticals / Q000627:therapeutic use; D013242:Sterilization / Q000379:methods*; D013295:Streptococcus mutans / Q000187:drug effects / Q000528:radiation effects; D013314:Stress, Mechanical; D013997:Time Factors; D014466:Ultraviolet Rays
chemical_list: D003037:Cobalt Radioisotopes; D019551:Dental Disinfectants; D003764:Dental Materials; D020724:Elastomers; D019275:Radiopharmaceuticals; D000431:Ethanol; D010463:Peracetic Acid; D005976:Glutaral