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 δ) 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 δ and G′ provides the most optimum masticatory function for patients requiring the provision of soft liners on their dentures.

Get full access to this article

View all access options for this article.

References

Ferry JD -1980-. Viscoelastic properties of polymers. 3rd ed. New York: John Wiley & Sons Inc.

Glantz P-O, Jones DW, Strandman E, El Ghazali S -1988-. Influence of tissue conditioners on the clinical deformation of maxillary complete dentures. Dent Mater4:8–14.

Hidaka O, Iwasaki M, Saito M, Morimoto T -1999-. Influence of clenching intensity on bite force balance, occlusal contact area, and average bite pressure. J Dent Res78:1336–1344.

Inoue K, Arikawa H, Fujii K, Shinohara N, Kawahata N -1985-. Viscoelastic properties of oral soft tissue. A method of determining elastic modulus of oral soft tissue. Dent Mater J4:47–53.

Jones DW, Sutow EJ, Hall GC, Tobin WM, Graham BS -1988-. Dental soft polymers: plasticizer composition and leachability. Dent Mater4:1–7.

Kalachandra S, Minton RJ, Taylor DF, Takamata T -1995-. Characterization of some proprietary soft lining materials. J Mater Sci Mater Med6:647–652.

McCabe JF -1976-. Soft lining materials: composition and structure. J Oral Rehabil3:273–278.

McCabe JF -1998-. A polyvinylsiloxane denture soft lining material. J Dent26:521–526.

Murata H, McCabe JF, Jepson NJ, Hamada T -1996-. The influence of immersion solutions on the viscoelasticity of temporary soft lining materials. Dent Mater12:19–24.

10.

Murata H, Hamada T, Djulaeha E, Nikawa H -1998-. Rheology of tissue conditioners. J Prosthet Dent79:188–199.

11.

Murata H, Taguchi N, Hamada T, McCabe JF -2000-. Dynamic viscoelastic properties and the age changes of long-term soft denture liners. Biomaterials21:1421–1427.

12.

Murayama T, Bell JP -1970-. Relationship between the network structure and dynamic mechanical properties of a typical amine-cured epoxy polymer. J Polymer Sci8-A-2-:437–445.

13.

Nielsen LE, Landel RF -1994-. Mechanical properties of polymers and composites. 2nd ed. New York: Marcel Dekker Inc.

14.

Seymour RA, Simpson JM, Charlton JE, Phillips ME -1985-. An evaluation of length and phrase of visual analogue scales in dental pain. Pain21:177–185.

15.

Waters M, Jagger R, Williams K, Jerolimov V -1996-. Dynamic mechanical thermal analysis of denture soft lining materials. Biomaterials17:1627–1630.

16.

Wright PS -1984-. The success and failure of denture soft-lining materials in clinical use. J Dent12:319–327.