Volumetric dimensional change of six direct core materials
| Autor: | Michael A. Cochran, B. Keith Moore, Jeffrey A. Platt, Supattriya Chutinan |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Analysis of Variance
Absorption (acoustics) Materials science Crowns Resin composite Silicones Glass ionomer cement Mixing (process engineering) Water Core (manufacturing) Composite Resins Statistics Nonparametric Silicone oil Absorption chemistry.chemical_compound Distilled water chemistry Glass Ionomer Cements Mechanics of Materials General Materials Science Dimethylpolysiloxanes Desiccation Composite material General Dentistry Shrinkage |
| Zdroj: | Dental Materials. 20:345-351 |
| ISSN: | 0109-5641 |
| DOI: | 10.1016/s0109-5641(03)00127-1 |
| Popis: | Summary Objectives. This study evaluated the influence of water on the volumetric dimensional change of six direct placement core build-up materials by using Archimedes’ principle. Methods. The effect on dimensional change due to the setting reaction was determined through the use of a silicone oil storage medium. The materials used were two dual-cured resin composites (CoreStore and Build-It FR), two chemically activated resin composites (CorePaste and Ti-Core), one metal-reinforced glass ionomer cement (Ketac-Silver), and one resin-modified glass ionomer (Fuji II LC Core). Using the manufacturers’ instructions for each material, cylindrical specimens were prepared with dimensions of 7 ^ 0.1 mm in diameter and 2 ^ 0.1 mm in height. Each material had four groups ðn ¼ 5Þ based on storage conditions; silicone oil at 23 and 37 8C and distilled water at 23 and 37 8C. A 0.01 mg resolution balance was used to determine volumetric dimensional change using an Archimedean equation. Measurements were made 30 min after mixing, and at the time intervals of 1, 14, and 56 days. Results. All materials exhibited dimensional change. Ketac-Silver had the most shrinkage in silicone oil and Fuji II LC showed the highest expansion in distilled water. The glass ionomer materials showed more change than did any of the resin composite materials. Significance. Current direct placement core materials show variation in the amount of volumetric dimensional change seen over a period of 56 days. Q 2003 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved. |
| Databáze: | OpenAIRE |
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