title: Dynamic viscoelasticity of soft liners and masticatory function.
abstract: Soft denture liners are used for edentulous patients to cushion functional forces. We hypothesized that the application of soft liners having viscoelastic properties would lead to the most marked improvement in masticatory function. The shear storage modulus (G'), shear loss modulus (G''), and loss tangent (tan delta) were determined for 6 materials by means of a dynamic viscoelastometer. Masticatory function of ten subjects was evaluated by measurements of maximum bite forces and chewing times and frequencies for 2 food samples, and by the use of visual analogue scales. The acrylic materials exhibited viscoelastic behavior, while the silicones exhibited elastic behavior. The improvement in masticatory function compared with hard resin was found to be in the order: acrylic permanent materials > silicone > acrylic temporary materials. The results suggest that the use of materials with higher tan delta and G' provides the most optimum masticatory function for patients requiring the provision of soft liners on their dentures.
authors.affiliation: Department of Prosthetic Dentistry, Hiroshima University Faculty of Dentistry, Japan. hmurata@hiroshima-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Murata
authors.forename: N
authors.initials: N
authors.lastname: Taguchi
authors.forename: T
authors.initials: T
authors.lastname: Hamada
authors.forename: M
authors.initials: M
authors.lastname: Kawamura
authors.forename: J F
authors.initials: JF
authors.lastname: McCabe
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001672:Biocompatible Materials / Q000737:chemistry*; D001732:Bite Force; D003822:Denture Liners; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D004548:Elasticity; D005502:Food; D005782:Gels / Q000737:chemistry; D006801:Humans; D008409:Mastication / Q000502:physiology*; D008768:Methylmethacrylates / Q000737:chemistry; D017060:Patient Satisfaction; D012212:Rheology; D012826:Silicone Elastomers / Q000737:chemistry; D013223:Statistics as Topic; D018709:Statistics, Nonparametric; D013314:Stress, Mechanical; D013997:Time Factors; D014783:Viscosity
chemical_list: D000180:Acrylic Resins; D001672:Biocompatible Materials; D004129:Dimethylpolysiloxanes; D005782:Gels; C020964:MDX 4-4210; D008768:Methylmethacrylates; D012826:Silicone Elastomers; C069456:Hydro-Cast dental tissue conditioner; C076423:Coe Super-Soft