Stain Susceptibility of Composite Resins: Pigment Penetration Analysis

Abstract

Composite resins are considered the material of choice for esthetic direct restorations, considering both their satisfying esthetic and mechanical properties. The success of composite resin restorations depends highly on their color stability. Discoloration causes color mismatch, consequent patient dissatisfaction, and eventually additional costs for correction/replacement of the restoration. The purpose of this study was to evaluate the degree of pigment penetration within the composite resins, in order to understand how discoloration can be treated properly. Two different commercially available composite resins were compared in the study: a nano-filled composite resin and a non-homogeneous micro-hybrid composite resin. A coffee solution was used to induce staining of the materials. Subsequently, the penetration of the pigments was measured by analyzing the color from the outside to the inside of the specimen. 14 levels were analyzed starting from 0.1 mm to 3.0 mm in depth. The ANOVA test demonstrated a statistically significant difference (p < 0.0001) between test and control groups up to a depth of 1.0 mm for the nano-filled composite and up to a depth of 2.0 mm for the non-homogeneous micro-hybrid composite. The two composite resin materials, subjected to pigmenting treatment, underwent a color variation with different patterns.

Effect of Laser and Conventional Office Bleaching and Polishing on the Color Change of Stained Nanohybrid and Microhybrid Composite Resin

“…Recent studies showed that the penetration of water and pigments was higher in nanohybrid composite resin than in microhybrid composite resin, which was attributed to a lack of complete silanization of nanoparticle clusters and prepolymerized fillers in nanohybrid composite resin. These properties are also seen in Grandio composite resin [24][25][26]. In addition, some researchers have reported that an increase in the size of filler particles increases the composite resin's color stability by decreasing the ratio of the organic filler matrix [26,27].…”

“…Although the present study collected important data on the effects of laser, Sof-Lex discs, and bleaching agents on removing stains from composite resin surfaces. The discoloring solution in the present study (coffee) does not represent all the solutions the teeth might be exposed to clinically [24].…”

Comparative Efficacy of Four Stain Removal Methods for Bleach-Shade Composite Resins after Immersion in Staining Solutions: An In Vitro Study

“…They stated that it could be due to the composition of the resin matrix and the porosity of the nanoclusters and glass fillers. Cinelli et al [ 24 ] concluded that the particles of the nanoclusters are not individually silanized and resulted in more water and pigment infiltration in nanohybrid composite resins.…”

Impact of smoking on resin bonded restorations: A narrative review

“…The choice of composite material used for dental restorations is another factor that can influence their aesthetic stability. Different composite materials vary in their susceptibility to color changes, making material selection a crucial consideration when planning treatments for patients who smoke 12 .…”