title: Latex and non-latex orthodontic elastic force loss due to cyclic temperature.
abstract: The purpose of this study was to compare the force loss of 1/4 inch (6.35mm) 3.5oz (99g) medium latex elastics from Ormco Corp. to non-latex elastics from ClassOne Orthodontics and Phoenix after being cycled between different temperatures. Elastics were stretched to 1.57 inches (40mm) on jigs and cycled in water baths for 4 minutes at 5 degrees C and 37 degrees C, 21 degrees C and 37 degrees C, 5 degrees C and 50 degrees C, 37 degrees C and 50 degrees C, and a control group was held at 3 degrees 7 degrees C. The force produced by new elastics and elastics after incubation was measured using a Mini 44 Instron.
  
  
  RESULTS
  All elastics experienced increased force loss that correlated with increased temperatures with the exception of Ormco latex elastics. The latex elastics had the greatest force loss upon cycling between 5 degrees C and 50 degrees C while the non-latex elastics had the greatest force loss while cycling between 37 degrees C and 50 degrees C. All elastics were strongest when cycled between 5 degrees C and 37 degrees C.
  
  
  CONCLUSIONS
  This study suggests that hot liquids reduce the force of latex and non-latex elastics even when cycled between hot temperatures for brief periods of time.
authors.affiliation: University of Texas School of Dentistry, Houston, USA. sebastian.z.paige@uth.tmc.edu
authors.forename: Sebastian Z
authors.initials: SZ
authors.lastname: Paige
authors.forename: Jeryl D
authors.initials: JD
authors.lastname: English
authors.forename: Gary N
authors.initials: GN
authors.lastname: Frey
authors.forename: Harry I
authors.initials: HI
authors.lastname: Bussa
authors.forename: Kathleen R
authors.initials: KR
authors.lastname: McGrory
authors.forename: Randy K
authors.initials: RK
authors.lastname: Ellis
authors.forename: Joe C
authors.initials: JC
authors.lastname: Ontiveros
mesh_terms: D003799:Dental Stress Analysis; D004548:Elasticity; D020724:Elastomers; D006358:Hot Temperature; D006801:Humans; D007840:Latex; D008422:Materials Testing; D009967:Orthodontic Appliances; D013314:Stress, Mechanical
chemical_list: D020724:Elastomers; D007840:Latex