J Korean Acad Conserv Dent.  2008 Jan;33(1):1-8. 10.5395/JKACD.2008.33.1.001.

Surface roughness of experimental composite resins using confocal laser scanning microscope

• Bae JH
• Lee MA
• Cho BH

• KMID: 1986744
• DOI: http://doi.org/10.5395/JKACD.2008.33.1.001

Abstract

The purpose of this study was to evaluate the effect of a new resin monomer, filler size and polishing technique on the surface roughness of composite resin restorations using confocal laser scanning microscopy. By adding new methoxylated Bis-GMA (Bis-M-GMA, 2,2-bis[4-(2-methoxy-3-methacryloyloxy propoxy) phenyl] propane) having low viscosity, the content of TEGDMA might be decreased. Three experimental composite resins were made: EX1 (Bis-M-GMA/TEGDMA = 95/5 wt%, 40 mm nanofillers); EX2 (Bis-M-GMA/TEGDMA = 95/5 wt%, 20 mm nanofillers); EX3 (Bis-GMA/TEGDMA = 70/30 wt%, 40 mm nanofillers). Filtek Z250 was used as a reference. Nine specimens (6 mm in diameter and 2 mm in thickness) for each experimental composite resin and Filtek Z250 were fabricated in a teflon mold and assigned to three groups. In Mylar strip group, specimens were left undisturbed. In Sof-lex group, specimens were ground with #1000 SiC paper and polished with Sof-lex discs. In DiaPolisher group, specimens were ground with #1000 SiC paper and polished with DiaPolisher polishing points. The Ra (Average roughness), Rq (Root mean square roughness), Rv (Valley roughness), Rp (Peak roughness), Rc (2D roughness) and Sc (3D roughness) values were determined using confocal laser scanning microscopy. The data were statistically analyzed by Two-way ANOVA and Tukey multiple comparisons test (p = 0.05). The type of composite resin and polishing technique significantly affected the surface roughness of the composite resin restorations (p < 0.001). EX3 showed the smoothest surface compared to the other composite resins (p < 0.05). Mylar strip resulted in smoother surface than other polishing techniques (p < 0.05). Bis-M-GMA, a new resin monomer having low viscosity, might reduce the amount of diluent, but showed adverse effect on the surface roughness of composite resin restorations.

Keyword

Bis-M-GMA; confocal laser scanning microscopy; filler size; new resin monomer; surface roughness

MeSH Terms

Benzhydryl Compounds
Bisphenol A-Glycidyl Methacrylate
Composite Resins
Fungi
Methacrylates
Microscopy, Confocal
Polyethylene Glycols
Polyethylene Terephthalates
Polymethacrylic Acids
Polytetrafluoroethylene
Viscosity
Benzhydryl Compounds
Bisphenol A-Glycidyl Methacrylate
Composite Resins
Methacrylates
Polyethylene Glycols
Polyethylene Terephthalates
Polymethacrylic Acids
Polytetrafluoroethylene

Figure

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  Figure 1 Confocal laser scanning micrography of EX3 Sof-lex group (× 200).

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  Figure 2 3D image of EX3 Sof-lex group obtained using confocal laser scanning micrography (× 200).

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  Figure 3 Cross-sectional profile obtained from the intersection line in Figure 1 & 2.

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