Polishing mechanism of light-initiated dental composite: Geometric optics approach
Journal
Journal of the Formosan Medical Association
Journal Volume
115
Journal Issue
12
Pages
1053-1060
Date Issued
2016
Author(s)
Abstract
Background/Purpose For light-initiated dental hybrid composites, reinforcing particles are much stiffer than the matrix, which makes the surface rugged after inadequate polish and favors bacterial adhesion and biofilm redevelopment. The aim of the study was to investigate the polishing mechanism via the geometric optics approach. Methods We defined the polishing abilities of six instruments using the obtained gloss values through the geometric optics approach (micro-Tri-gloss with 20°, 60°, and 85° measurement angles). The surface texture was validated using a field emission scanning electron microscope (FE-SEM). Based on the gloss values, we sorted polishing tools into three abrasive levels, and proposed polishing sequences to test the hypothesis that similar abrasive levels would leave equivalent gloss levels on dental composites. Results The three proposed, tested polishing sequences included: S1, Sof-Lex XT coarse disc, Sof-Lex XT fine disc, and OccluBrush; S2, Sof-Lex XT coarse disc, Prisma Gloss polishing paste, and OccluBrush; and S3, Sof-Lex XT coarse disc, Enhance finishing cups, and OccluBrush. S1 demonstrated significantly higher surface gloss than the other procedures (p < 0.05). The surface textures (FE-SEM micrographs) correlated well with the obtained gloss values. Conclusion Nominally similar abrasive abilities did not result in equivalent polish levels, indicating that the polishing tools must be evaluated and cannot be judged based on their compositions or abrasive sizes. The geometric optic approach is an efficient and nondestructive method to characterize the polished surface of dental composites.
SDGs
Publisher
Elsevier B.V.
Type
journal article