Comparisons between different groups Table 
Omnichroma
Mean and standard deviation of roughness at baseline, after one day, and after 14 days and comparison between different groups









Means with different superscript letters were significantly different as Means with the same superscript letters were insignificantly different as 
Bar chart representing a comparison between all groups regarding surface roughness at all intervalsComparison between different intervals was performed by using the One-Way ANOVA test, which revealed a significant difference in all groups as At baseline: Omnichroma coffee O1 and Omnichroma distilled water O2 were significantly the lowest with insignificant difference between them (same have letter a), while Venus Peral Coffee V1 and Venus Peral distilled water V2 was significantly the highest with insignificant difference between them (same have letter b).After one day: Omnichroma distilled water O2, Venus Peral distilled water V2 were significantly the lowest with insignificant difference between them (same have letter c), then Omnichroma coffee O1, while Venus Peral Coffee V2 was significantly the highest.After two weeks: Omnichroma coffee O1 and Venus Peral Coffee V1 were significantly the highest with insignificant difference between them (both have the letter a), while Omnichroma distilled water O2 and Venus Peral distilled water V2 were significantly the lowest with insignificant difference between them (same have letter b)