Surface roughness and color changes of dental PEEK related to staining beverages and cleaning methods

• Published in: Materials today : proceedings Vol. 78; pp. 221 - 226
• Main Authors: Porojan, Liliana, Roxana Toma, Flavia, Diana Vasiliu, Roxana, Matichescu, Anamaria
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 2023
• Subjects: Cleaning; Color stability; Dental PEEK; Staining; Surface roughness; Dental PEEK; Staining; Surface roughness; Cleaning; Color stability
• DOI: 10.1016/j.matpr.2022.10.174
• ISSN: 2214-7853

Considering that the microstructure, texture and surface characteristics are relevant factors that could affect the appearance and resistance of a material, the study aims to evaluate in vitro, the surface roughness development and color changes related to staining beverages and cleaning methods after simulated periods of clinical use. The discoloration processes of PEEK materials are caused by intrinsic or extrinsic factors and still require elucidation. Three types of unmodified or modified PEEK CAD/CAD materials were selected for investigation: Finoframe, Juvora medical and BioHPP-a reinforced material. Four different staining media were involved: hot coffee, black tea, cold juice, and distilled water as control. For staining thermal cycling was performed between a hot coffee/tea bath (55 °C) and a bath filled with distilled water (37 °C), respective between a cold juice bath (5 °C) and a bath filled with distilled water (37 °C). For cleaning, a chemical method and mechanical brushing were selected. Simulated periods of clinical use were taken into consideration. Roughness measurements (Ra and Rz) were done after each period. Color changes (ΔE*) were calculated based on the CIE L*a*b* color system. Statistical analyses were performed, paired t-Test for comparisons between the means and Spearman correlations to assess relationships between roughness and color changes. After staining beverages, a significant decreased in Ra values for all three materials that were immersed in juice and, for B and F in tea, were measured. Perceivable changes have been identified for J in coffee and for B in tea. After brushing, Ra significant decreased for J, in all immersion environments and no perceivable color changes were reported. The chemical cleaning caused a significant decrease in surface roughness values for B and F, in all immersion environments and color changes were perceivable for J in juice. Surface characteristics were affected by staining, mechanical and chemical cleaning; during the study, no marked color changes of PEEK were detected.