Abstract
Background: Bulk-fill resin composite has been introduced, their manufacturers claimed that they can be applied in bulks of 4mm, without necessitating a prolonged curing time, or a light curing unit with increased irradiance. Thus, this study was conducted to evaluate the effect of resin thickness and curing time on the micro-hardness of two bulk -fill resin composites: Tetric Evo-Ceram [TE], and X-trafil [XF]. Material and Methods: 120 cylindrical specimens were prepared and divided into 24 groups (n=5/group), representing the two bulk-fill resin composites, three different material thicknesses (2, 3 and 4 mm) and the four curing times used in the study (10, 20, 40, and 60 seconds). The specimens were light-cured from the top surface only. Specimens were stored in light proof containers in complete darkness at 37°C for 24 hours. Micro-hardness test was conducted on both top and bottom surfaces using Vickers micro-hardness tester with 500 g load and a dwell time of 15 seconds. Data were statistically analyzed by Four-way ANOVA of Variance. The significance level was set at P = 0.05. Pearson Correlation used to determine significant correlations between mean micro-hardness (top) and (bottom) surfaces. Results: Four way-ANOVA shows that different tested materials produce a statistically significant effect on mean micro-hardness (VHN) at p=0.001, while thickness, curing time, and surface revealed statistically non-significant effect on mean micro-hardness (VHN) at p=0.05. [XF] (92.01±3.15 VHN) showed statistically significant higher mean micro-hardness than [TE] (54.13±4.96 VHN). Pearson Correlation revealed that there was a significant direct correlation between micro-hardness (bottom) and mean micro-hardness (top) (mm), r = 0.985, p (2-tailed) =0.001. Conclusions: Within the limitations of this study, the bulk-fill resin composites used in this study can be placed and cured properly in the 4 mm bulk.
Recommended Citation
S. M. Nagi et al., "Effect of Resin Thickness, and Curing Time on the Micro-Hardness of Bulk-Fill Resin Composites," Journal of Clinical and Experimental Dentistry, vol. 7, no. 5, pp. e600 - e604, Spanish Society of Oral Surgery, Jan 2015.
The definitive version is available at https://doi.org/10.4317/jced.52536
Department(s)
Chemical and Biochemical Engineering
Keywords and Phrases
Bulk-fill resin composite; Curing time; Micro-hardness; Thickness
International Standard Serial Number (ISSN)
1989-5488
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 National Center for Biotechnology Information, All rights reserved.
Publication Date
01 Jan 2015
