Influence of restorative material translucency on the chameleon effect.

Blending of artificial restoration materials to the natural tooth is challenging. Beyond just color, optical properties, particularly translucency, substantially influence the final appearance. The more chameleon effect that the restorative materials exhibit, the more natural looking restorations. The purpose of this study is to investigate the influence of restorative material translucency on the chameleon effect. Five types of resin composite in three different shades as well as one shade of conventional glass ionomer cement were fabricated into disks. To analyze the chameleon effect, glass ceramic blocks were milled to create four wells in each block. The restorative materials were filled into the wells. The color was measured with CIE Lab* every 6 months. Statistical analysis was conducted using Two-Way Repeated Measures ANOVA. The material with the highest translucency was flowable resin composite. The high translucency materials exhibited an immediate chameleon effect, as did the bulk-fill resin composites, which are low translucency. Both high and low translucency materials exhibited a delayed chameleon effect for 3 years, except for the bulk fill resin composites. The translucency of the restorative materials had a 68% positive correlation with their chameleon effect. The age of the restoration is one important factor influencing the color blending.