title: Dynamic mechanical thermal analysis of maxillofacial elastomers.
abstract: BACKGROUND
  Maxillofacial prosthetic materials should simulate the oral tissues as much as possible and therefore have a similar flexibility and resilience. In light of the oral tissues constantly moving, the dynamic deformation properties of maxillofacial materials would seem the most relevant.
  
  
  OBJECTIVE
  In this study, dynamic mechanical thermal analysis was used to evaluate the deformation properties of five silicone rubber materials used to construct facial prostheses. The technique involves the application of a sinusoidally oscillating stress to a material and analyzes how the material elastically or viscoelastically responds to the stress. The dynamic mechanical thermal analysis can operate at a fixed frequency or range of frequencies over a specific temperature range and also isothermally as a function of time.
  
  
  RESULTS
  Cosmesil and A-2186 materials were the most resilient materials and Silbione had the greater energy absorption capacity, which was particularly noticeable at the higher frequencies. Silbione also had a lower shear modulus (G'), which indicated it was more flexible than the other materials.
  
  
  CONCLUSIONS
  The dynamic mechanical thermal analysis proved to be a rapid, reliable, and convenient method for the determination of viscoelastic properties of maxillofacial materials.
authors.affiliation: Department of Basic Dental Science, University of Wales College of Medicine, Dental School, Cardiff, United Kingdom.
authors.forename: M
authors.initials: M
authors.lastname: Waters
authors.forename: R
authors.initials: R
authors.lastname: Jagger
authors.forename: G
authors.initials: G
authors.lastname: Polyzois
authors.forename: K
authors.initials: K
authors.lastname: Williams
mesh_terms: D000704:Analysis of Variance; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D004548:Elasticity; D006801:Humans; D008422:Materials Testing; D008447:Maxillofacial Prosthesis; D009061:Mouth Mucosa / Q000502:physiology; D009068:Movement; D018583:Pliability; D015203:Reproducibility of Results; D012826:Silicone Elastomers / Q000737:chemistry*; D012828:Silicones / Q000737:chemistry; D013314:Stress, Mechanical; D013696:Temperature; D013718:Tensile Strength; D013816:Thermodynamics; D014783:Viscosity
chemical_list: C076788:A 2186; D004129:Dimethylpolysiloxanes; C027899:Mollomed; D012826:Silicone Elastomers; D012828:Silicones; C044914:cosmesil