Evaluation of Surface Microhardness of Silver and Zirconia Reinforced Glass-ionomers with and without Microhydroxyapatite
Statement of problem: Hardness of restorative materials like glass-ionomer is an important factor in the longevity of restoration. Objectives: The aim of this study was to evaluate the microhardness of glass-ionomer modified with different materials. Materials and Methods: Sixty disk-shaped specim...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Shiraz University of Medical Sciences
2017-12-01
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| Series: | Journal of Dental Biomaterial |
| Subjects: | |
| Online Access: | http://jdb.sums.ac.ir/index.php/jdb/article/view/238/162 |
| Summary: | Statement of problem: Hardness of restorative materials like glass-ionomer is an important factor in the longevity of restoration.
Objectives: The aim of this study was to evaluate the microhardness of glass-ionomer modified with different materials.
Materials and Methods: Sixty disk-shaped specimens were examined in six groups in this study, including conventional glass-ionomer (Shofu, Japan), zirconia-reinforced glass-ionomer (Zirconomer, Shofu, Kyoto, Japan), silver-reinforced glass-ionomer (HI-DENSE XP, Shofu, Kyoto, Japan) and mixture of these three types of glass-ionomer with 20 wt% of microhydroxyapatite (Sigma-Aldrich, St. Louis, USA). All the specimens were stored in deionized water for 24 hours. Then Vickers microhardness test was carried out and the results were analyzed by using two-way ANOVA test and paired t-test (P<0.05).
Results: Zirconia-reinforced glass-ionomer with microhydroxyapatite exhibited significantly higher microhardness in comparison with other groups (P<0.001). Conventional glass-ionomer with microhydroxyapatite showed the lowest microhardness (P<0.001). After incorporation of microhydroxyapatite in both conventional and silver-reinforced glass-ionomer groups, microhardness decreased significantly (P<0.001).The microhardness of top and bottom of all groups was significantly different. (P<0.001).
Conclusions: Incorporation of 20% microhydroxyapatite to zirconia-reinforced glass-ionomer can improve microhardness. |
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| ISSN: | 2383-3971 2383-398X |