## Abstract Previous observations on polysaccharides used as viscoelastic agents in ophthalmic surgery suggest that the pseudoplasticity of solutions of hyaluronan (HA) and the low surface tension of hydroxypropylmethylcellulose (HPMC) solutions are physical properties that make these solutions use
Viscoelastic and adherence properties of dental relining materials
β Scribed by Buch, D. ;Wehbi, D. ;Roques-Carmes, C.
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 581 KB
- Volume
- 29
- Category
- Article
- ISSN
- 0021-9304
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β¦ Synopsis
The viscoelastic properties of three classes of soft relining materials (acrylic resins, silicones, and EVA copolymers) were studied comparatively. Their behaviors were investigated by in vitro tests at a frequency o = 1 Hz, which simulates the masticatory cycle. The experimental parameter was the temperature (T). Black graphs giving the variations of the stiffness K-proportional to the complex viscoelastic modulus E*(T),,,-according to the phase angle 6, were used for a predictive approach to increase the comfort of removable dentures. Cole-Cole diagrams, describing the variation of the loss modulus E ( T ) , in relation to the stor-age modulus E'(T), additionally provide quantitative data. The values obtained were related to the noninteger parameter h used for modelization of the viscoelastic behavior of the materials by means of nonlinear Zener models. An attempt was made to correlate the experimental data to the viscoelastic energy loss observed when instability of the prosthetic structure occurs. This attempt takes into account the formation of "cracks" (areas of inadaptation) between the prosthetic intrados and the mucosa.
π SIMILAR VOLUMES
The double-torsion technique has been used to determine critical stress intensity factor (K1,) values for a range of composites and glass ionomer cements used in restorative dentistry. From these values and determined elastic modulus ( E ) and tensile strength (cT) values, two other fracture propert
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