Effect of Silane Coupling Treatment of Filler Surface on Color Stability of Resin Composite

• Published in: The JAPANESE JOURNAL OF CONSERVATIVE DENTISTRY Vol. 60; no. 2; pp. 78 - 88
• Main Authors: IDE Shotaro, YAMAGUCHI Mai, TANAKA Tomohisa, Michael W. MYERS, TOKO Teruo, MANABE Atsufumi
• Format: Journal Article
• Language: English; Japanese
• Published: The Japanese Society of Conservative Dentistry 30.04.2017
• ISSN: 0387-2343
• DOI: 10.11471/shikahozon.60.78

[Abstract] [Purpose] : The purpose of this study was to evaluate the effect of silane coupling treatment on the color stability and surface texture of resin composites. [Materials and Methods] : Two types of experimental light-cured resin composite containing silica particles that were silane coupling treated (SC (+)) or untreated (SC (-)) were used in this study. Each composite material was packed into a ring-shaped stainless-steel mold and photopolymerized. A total of 40 SC (+) specimens and 40 SC (-) specimens were fabricated. The specimens were polished with #600, #1000, #1500, and #4000 silicon carbide paper, and finished with an alumina suspension. Half the SC (+) and SC (-) specimens (20 of each) were thermocycled in rhodamine B solution for 1,000 or 10,000 cycles. The other half were immersed in rhodamine B solution for 24 h, 48 h, 72 h, or 7 days. Opacity value, ΔE*ab, surface roughness, and water absorption were measured after thermocycling or immersion. The surface texture of the specimens was observed by scanning electron microscopy. [Results] : ΔE*ab, surface roughness, and water absorption were significantly higher in SC (-) than in SC (+). There was no significant difference between the opacity values of SC (-) and SC (+) after immersion, but a significant difference was observed after thermocycling in both. SC (-) showed a significant increase in opacity value as the repetition number of thermal cycles increased. [Conclusion] : In SC (-), during thermocycling, gaps formed between the resin matrix and filler due to the deterioration of incomplete adhesion. Water absorption into the gap allowed the dye to penetrate the interior of the composite, as well as the surface, causing discoloration of the bulk composite. Our results suggested that silane coupling treatment of the filler surface is related to the color stability of the resin composite.