Poisson's ratio of glass-polyalkenoate (“glass-ionomer”) cements determined by an ultrasonic pulse method
✍ Scribed by A. O. Akinmade; J. W. Nicholson
- Publisher
- Springer
- Year
- 1995
- Tongue
- English
- Weight
- 292 KB
- Volume
- 6
- Category
- Article
- ISSN
- 0957-4530
No coin nor oath required. For personal study only.
✦ Synopsis
Poisson's ratio has been determined for four glass-polyalkenoate cements; one experimental luting type, one experimental restorative type, one commercial restorative type (Chelon-Fil, ex. ESPE GmbH) and one cermet-reinforced cement EChelon-Silver, also ex. ESPE]. An ultrasonic pulse method was employed for the Poisson's ratio determinations. For the restorative materials, including the cermet-reinforced cement, the values obtained were all in the region of 0.3. For the luting cement, on the other hand, the values found were in the range of 0.35. This difference was consistent with the relatively increased water content and reduced glass content of the luting cement. The cements based on poly(acrylic acid) showed slight, but statistically significant, increases in Poisson's ratio up to 80 days, whereas the cements based on poly(maleic acid) showed no significant changes in Poisson's ratio with time.