Abstract | OBJECTIVE: The purpose of this study was to investigate the effect of the applied load in a rolling-ball device on the surface contact fatigue of two dental filling materials: a microfilled composite (FA) and a glass ionomer (GFII). METHODS: Disk specimens 10 mm diameter by 1.5 mm thick were set into cavities cut in plates of PMMA. After setting, the specimens were ground and polished using wet- carborundum paper followed by 1 microm alumina and then stored for 24 h in water at 23 degrees C. The surface fatigue test was carried out using loads ranging from 100 to 500 gf through a ruby ball 2 mm diameter using a rolling-ball device. The ball was set to rotate at 720 rpm and a surface profile was determined on impressions recorded at regular intervals. Fatigue life was defined as the number of cycles to produce a track 5 microm deep and was determined by interpolation. Data were statistically analyzed by ANOVA and t-tests at a significance level of 0.05. RESULTS: At loads ranging from 200 to 500 gf the fatigue life was 0.7-10.6 x 10(5) cycles for FA, and 0.7-4.8 x 10(3) cycles for GFII. For both materials the fatigue life was reduced significantly by increasing the test load (p<0.05). The surface contact fatigue life for FA was at least 100 times greater than that for GFII at all loads. SIGNIFICANCE: The rolling ball device was confirmed as a simple and meaningful device for the study of surface contact fatigue. A microfilled composite is very much more resistant to contact fatigue than a glass ionomer.
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Authors | Koichi Fujii, Thomas E Carrick, Robert Bicker, John F McCabe |
Journal | Dental materials : official publication of the Academy of Dental Materials
(Dent Mater)
Vol. 20
Issue 10
Pg. 931-8
(Dec 2004)
ISSN: 0109-5641 [Print] England |
PMID | 15501321
(Publication Type: Journal Article, Validation Study)
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Chemical References |
- Composite Resins
- Filtek A110 composite resin
- Glass Ionomer Cements
- Fuji glass-ionomer lining cement
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Topics |
- Composite Resins
- Dental Restoration Wear
- Dental Restoration, Permanent
- Dental Stress Analysis
(instrumentation)
- Friction
- Glass Ionomer Cements
- Materials Testing
- Surface Properties
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