RESEARCH AND EDUCATION Effect of mouth rinses on the stainability of monolithic lithium disilicate glass-ceramics with different surface treatments: An in vitro study

Statement of problem. Mouth rinses have been reported to cause tooth surface discoloration. However, information regarding their effect on the stainability of monolithic glass-ceramics with different surface treatments is lacking.Purpose. The purpose of this in vitro study was to assess the effect of mouth rinses on the color change of milled and pressed monolithic lithium disilicate glass-ceramics with different surface treatments. Material and methods. Fifty-six o12x1.5-mm disk specimens were fabricated using 2 different processing techniques: milling and pressing. Each group was subdivided into 2 subgroups according to surface treatments: glazed and polished. Specimens were then immersed in 2 different types of mouth rinse (n=7): chlorhexidine (CHX) and Listerine (LST). Color parameters were assessed using a digital spectrophotometer. Color difference (AE00) was calculated and compared with perceptibility (AE00=0.8) and acceptability (AE00=1.8) thresholds. The data were analyzed using ANOVA and Tukey post hoc tests (alpha=.05).Results. The color difference (AE00) was significantly affected by the type of processing technique, surface treatment, and mouth rinse (P.001) and their interaction (P=.008). All AE00 values were below the selected clinical acceptability threshold (AE00=1.8). Milled groups (AE00=1.13) showed greater discoloration than pressed groups (AE00=0.86). Glazed specimens (AE00=0.70) were more resistant to discoloration than polished specimens (AE00=1.28) and immersion in CHX (AE00=1.09) led to more discoloration than immersion in LST (AE00=0.89).Conclusions. The color of milled and pressed monolithic lithium disilicate glass-ceramics with different surface treatments was affected by using CHX and LST mouth rinses. Glazed lithium disilicate glass-ceramics showed less staining compared with those that were polished. Specimens immersed in CHX showed more discoloration than those immersed in LST. (J Prosthet Dent 2023;130:935.e1-e6)