Microhardness of bulk-fill vs. conventional resin composites polymerized with different curing times in different thicknesses

Ekin Dermanli; Elif Ozturk

doi:10.61139/ijdor.1829950

Microhardness of bulk-fill vs. conventional resin composites polymerized with different curing times in different thicknesses

Abstract

Objective: This study aimed to evaluate and compare the Vickers hardness values of two resin composites at both their top and bottom surfaces. Methods: A bulk-fill resin composite and a conventional composite material were used in this investigation. For each material, five disc-shaped specimens were fabricated with a diameter of 10 mm and thicknesses of either 2 mm or 4 mm. The samples were polymerized from the top surface for either 20 or 40 seconds, resulting in a total of eight experimental groups. Each specimen underwent three Vickers hardness measurements on both its upper and lower surfaces. Microhardness was assessed using a Vickers hardness tester applying a 300-g (2.94 N) load for a dwell time of 15 seconds. The resulting data were evaluated using the Kruskal–Wallis test with Bonferroni adjustment for multiple comparisons. Results: Significant differences were found between the hardness values measured at the top and bottom surfaces in all groups (p<0.05), with the exception of the conventional composite cured for 40 seconds at a 2-mm thickness, where no statistically significant difference was detected (VH_top = 98.1, VH_bottom = 94.4, p>0.05). For both materials, extending the curing time resulted in a statistically significant increase in microhardness at both surfaces (p<0.05). While changes in composite thickness did not influence the top surface hardness (p>0.05), increasing thickness led to reduced hardness values at the bottom surface (p<0.05). Conclusions: The thickness of the material was found to affect the bottom surface microhardness in both the bulk-fill and conventional composites. Additionally, extending the curing duration led to higher microhardness values at both the top and bottom surfaces of the evaluated materials.

Keywords

Supporting Institution

No funding resource is associated with this study.

Project Number

1

Ethical Statement

Not applicable

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Details

Primary Language

English

Subjects

Dental Materials and Equipment, Restorative Dentistry

Journal Section

Research Article

Authors

Ekin Dermanli This is me
0009-0002-7692-4878
Türkiye

Elif Ozturk ^*
0000-0003-1638-2739
Türkiye

Publication Date

December 31, 2025

Submission Date

December 2, 2025

Acceptance Date

December 30, 2025

Published in Issue

Year 2025 Volume: 5 Number: 3

DOI

https://doi.org/10.61139/ijdor.1829950

IZ

https://izlik.org/JA92DG59DG

Cite

RIS / Bibtex

APA

Dermanli, E., & Ozturk, E. (2025). Microhardness of bulk-fill vs. conventional resin composites polymerized with different curing times in different thicknesses. HRU International Journal of Dentistry and Oral Research, 5(3), 189-195. https://doi.org/10.61139/ijdor.1829950

AMA

1.Dermanli E, Ozturk E. Microhardness of bulk-fill vs. conventional resin composites polymerized with different curing times in different thicknesses. HRU Int J Dent Oral Res. 2025;5(3):189-195. doi:10.61139/ijdor.1829950

Chicago

Dermanli, Ekin, and Elif Ozturk. 2025. “Microhardness of Bulk-Fill Vs. Conventional Resin Composites Polymerized With Different Curing Times in Different Thicknesses”. HRU International Journal of Dentistry and Oral Research 5 (3): 189-95. https://doi.org/10.61139/ijdor.1829950.

EndNote

Dermanli E, Ozturk E (December 1, 2025) Microhardness of bulk-fill vs. conventional resin composites polymerized with different curing times in different thicknesses. HRU International Journal of Dentistry and Oral Research 5 3 189–195.

IEEE

[1]E. Dermanli and E. Ozturk, “Microhardness of bulk-fill vs. conventional resin composites polymerized with different curing times in different thicknesses”, HRU Int J Dent Oral Res, vol. 5, no. 3, pp. 189–195, Dec. 2025, doi: 10.61139/ijdor.1829950.

ISNAD

Dermanli, Ekin - Ozturk, Elif. “Microhardness of Bulk-Fill Vs. Conventional Resin Composites Polymerized With Different Curing Times in Different Thicknesses”. HRU International Journal of Dentistry and Oral Research 5/3 (December 1, 2025): 189-195. https://doi.org/10.61139/ijdor.1829950.

JAMA

1.Dermanli E, Ozturk E. Microhardness of bulk-fill vs. conventional resin composites polymerized with different curing times in different thicknesses. HRU Int J Dent Oral Res. 2025;5:189–195.

MLA

Dermanli, Ekin, and Elif Ozturk. “Microhardness of Bulk-Fill Vs. Conventional Resin Composites Polymerized With Different Curing Times in Different Thicknesses”. HRU International Journal of Dentistry and Oral Research, vol. 5, no. 3, Dec. 2025, pp. 189-95, doi:10.61139/ijdor.1829950.

Vancouver

1.Ekin Dermanli, Elif Ozturk. Microhardness of bulk-fill vs. conventional resin composites polymerized with different curing times in different thicknesses. HRU Int J Dent Oral Res. 2025 Dec. 1;5(3):189-95. doi:10.61139/ijdor.1829950