Evaluation of the Susceptibility to Staining of Artificial Teeth and the Influence of Surface Texture on Staining

抄録

Purpose : This study established a method of evaluating the susceptibility to staining of artificial teeth and clarified whether the surface texture of artificial teeth influences this staining tendency.
Materials and Methods : Conventional resin teeth (R), resin teeth with a special acrylic polymer (FX), conventional composite resin teeth (EF), and composite resin teeth with an enhanced amount of fluor monomer (PX) were used. To evaluate the influence of surface texture on the staining tendency, the following polishing methods were used : no polishing, barrel-polishing and buff-polishing. The surface texture was examined using a scanning electron microscope. To evaluate direct staining, the artificial teeth were immersed for 1 week in curry and fuchsin basic solutions. To assess protein adsorption, they were immersed for 1 week in a human parotid saliva solution and a solution containing bovine serum albumin. They were subsequently immersed in a plaque-disclosing agent for 24 hours and washed in water. Color changes after direct staining and protein adsorption testing were evaluated. Multiple comparison of the color difference values (ΔE^*ab) were evaluated using a Bonferroni test (p<0.01).
Results : Protein adsorption testing showed that EF was remarkably stained for all surface textures. The barrel-polished surfaces were coarser than the other surfaces. EF was remarkably stained compared to the other teeth.
Conclusion : It was demonstrated that the staining tendency of the conventional composite resin teeth is due to their high level of protein adsorption and that protein adsorption testing is a useful evaluation method. Also, it was recognized that surface roughness is an influencing factor on the staining tendency.