Water sorption of gingiva-shade composites and its influence on color stability

This study aimed to ascertain the water sorption of three gingival shade esthetic materials and understand the correlation between water sorption and color change when immersed in common food colorants.

Disc-shaped composites were fabricated and subjected to immersion in distilled water, followed by desiccation to ascertain water sorption values. Simultaneously, similarly shaped specimens were fabricated, measured for total color using a spectrophotometer before and after immersion in various colorant solutions. Pearson's correlation was used to ascertain if there was a positive linear relationship between values for water sorption and change in total color.

There was a statistically significant difference in mean water sorption data between the tested composites (p = 0.02, F value = 5.6). No correlation coefficients between water sorption and any tested composites in any colorant solutions were statistically significant (p ≥ 0.05), with the exception of PermaFlow Pink immersed in coffee (r = -0.635, p = 0.05).

All the tested composites exhibited favorable values for water sorption^. Over the studied period, water immersion produced a negligible change in color among all the tested specimens. All composites exhibited changes in color when exposed to food colorants with the largest relative change occurring for immersion in curry. There was no positive correlation between water sorption values and change in color.