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. 2021 Nov 11;13(22):3902.
doi: 10.3390/polym13223902.

Effects of Color Modifier on Degree of Monomer Conversion, Biaxial Flexural Strength, Surface Microhardness, and Water Sorption/Solubility of Resin Composites

Pipop Saikaew  1 , Patchara Phimolthares  2 , Pheeratas Phitakthanaakul  2 , Panthira Sirikul  2 , Suwannee Mekrakseree  2 , Piyaphong Panpisut  3   4
Affiliations

Effects of Color Modifier on Degree of Monomer Conversion, Biaxial Flexural Strength, Surface Microhardness, and Water Sorption/Solubility of Resin Composites

Pipop Saikaew et al. Polymers (Basel). .

Abstract

Color modifiers can be mixed with resin composites to mimic the shade of severely discolored tooth. The aim of this study was to assess the effects of a color modifier on the physical and mechanical properties of a resin composite. The composite was mixed with a color modifier at 0 wt% (group 1), 1 wt% (group 2), 2.5 wt% (group 3), or 5 wt% (group 4). The degree of monomer conversion (DC) was examined after light curing for 20 or 40 s. Biaxial flexural strength (BFS)/modulus (BFM), surface microhardness (SH), and water sorption (Wsp)/solubility (Wsl) were also tested. The DC of group 1 was significantly higher than that of groups 3 and 4. The increase in curing time from 20 to 40 s increased the DC by ~10%. The BFS, BFM, Wsp, and Wsl of all the groups were comparable. A negative correlation was detected between the concentration of color modifier and the BFS and DC, while a positive correlation was observed with Wsp. In conclusion, the color modifier reduced the DC of composites, but the conversion was improved by extending the curing time. The increase in color modifier concentration also correlated with a reduction in strength and the increase in the water sorption of the composites.

Keywords: biaxial flexural strength; color modifier; degree of monomer conversion; resin composite; surface microhardness; tetracycline-induced discoloration; water solubility; water sorption.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Example of using a composite mixed with a color modifier for restoring a severe tetracycline-induced discolored tooth. (A) A patient willing to restore the fracture of the lower left central incisor using direct resin composite; (B) resin composite mixed with the color modifier (grey shade), which was used to mimic the discolored dentin; (C) final outcome of the composite restoration that exhibits the natural appearance of the discolored tooth.
Figure 2
Figure 2
Schematic illustrating the methods used in the current study.
Figure 3
Figure 3
Representative FTIR spectra of composites before and after curing for 20 and 40 s from each group.
Figure 4
Figure 4
Appearance of specimens after mixing with color modifier.
Figure 5
Figure 5
The linear regression of each property versus the amount of the color modifier.
Figure 6
Figure 6
Representative force–displacement diagram from BFS testing.
Figure 7
Figure 7
The addition of color modifiers reduced the degree of monomer conversion of resin composites.
See this image and copyright information in PMC

References

    1. Enabulele J.E., Chukwumah N.M., Enabulele O. Tetracycline use in children and knowledge of its oral implications among nursing mothers. Pediatr. Dent. J. 2020;30:224–230. doi: 10.1016/j.pdj.2020.08.003. - DOI
    1. Faus-Matoses V., Faus-Matoses I., Ruiz-Bell E., Faus-Llacer V.J. Severe tetracycline dental discoloration: Restoration with conventional feldspathic ceramic veneers. A clinical report. J. Clin. Exp. Dent. 2017;9:e1379–e1382. doi: 10.4317/jced.54359. - DOI - PMC - PubMed
    1. Finkelstein D.L., Calamia J. Restoring Tetracycline-Stained Teeth with Feldspathic Porcelain Veneers. JCD. 2019;35:60–70.
    1. Araujo E., Perdigão J. Anterior Veneer Restorations-An Evidence-based Minimal-Intervention Perspective. J. Adhes. Dent. 2021;23:91–110. - PubMed
    1. Yanikian C., Yanikian F., Sundfeld D., Lins R., Martins L. Direct Composite Resin Veneers in Nonvital Teeth: A Still Viable Alternative to Mask Dark Substrates. Oper. Dent. 2019;44:E159–E166. doi: 10.2341/18-220-T. - DOI - PubMed

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