Mechanical properties of glass ionomers under static and dynamic loading.

Abstract

OBJECTIVES:

This study evaluated the mechanical properties under static and cyclic loading conditions of various types of glass ionomers used for bases and core build-ups under restorations.

METHODS:

Compressive strength and three-point flexural strength of two different glass ionomers and two metal-reinforced glass ionomers were determined 1 d after the start of mixing. The flexural fatigue resistance of these materials was measured in the load range of 650 g to 1050 g using a three-point bending machine, and fractured surfaces of the specimens were examined using SEM.

RESULTS:

All the glass ionomers exhibited similar compressive and flexural strengths. The results analyzed by Cox' proportional hazard model demonstrated that the admixed-type metal-reinforced glass ionomer had the highest fatigue resistance, while the water-hardening glass ionomer had the lowest fatigue resistance among the materials examined (p<0.5).

SIGNIFICANCE:

There was no significant improvement in the static mechanical properties from incorporating metal particles into the glass ionomers. However, the addition of metal particles as in the admixed-type metal-reinforced glass ionomer produced a material with increased fatigue resistance.

• Authors: H Nakajima, J H Watkins, K Arita, K Hanaoka, T Okabe
• Journal: Dental materials : official publication of the Academy of Dental Materials (Dent Mater) Vol. 12 Issue 1 Pg. 30-7 (Jan 1996) ISSN: 0109-5641 [Print] England
• PMID: 8598248 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Cermet Cements
• Glass Ionomer Cements
• Glass Ionomer Core Material
• Shofu Hybond
• Miracle Mix
• Silver

Topics

• Cermet Cements (chemistry)
• Chi-Square Distribution
• Dental Stress Analysis
• Glass (chemistry)
• Glass Ionomer Cements (chemistry)
• Materials Testing (methods)
• Microscopy, Electron, Scanning
• Pliability
• Proportional Hazards Models
• Regression Analysis
• Silver (chemistry)
• Statistics, Nonparametric
• Stress, Mechanical
• Surface Properties