The impact of intracanal medicaments on crown color, pH, and antimicrobial activity: a comparative study

This study aimed to compare the effects of intracanal medication pastes Bio-C Temp® (BC), UltraCal XS® (UC), and Pure Calcium Hydroxide (CH) on crown color change, pH, and antimicrobial activity. Color change was assessed using the CIEL*a*b* color space system parameter. pH values were measured at 3, 24, 72, and 168 hours. Antimicrobial activity was evaluated using agar diffusion and direct exposure tests. Statistical analyses were conducted using ANOVA, Kruskal-Wallis, and Friedman tests (α = 0.05). After 15 days, BC exhibited significantly greater color variation than the control, and higher L* values at 60 days compared to baseline (p < 0.05). BC demonstrated lower pH values than UC and CH at 3 and 72 hours (p < 0.05). In the agar diffusion test, BC produced a smaller microbial inhibition halo than UC and CH. In the direct exposure test, CH completely inhibited microbial growth, whereas BC showed microbial growth at all evaluated time points. In conclusion, BC resulted in greater crown color change, lower pH, and reduced antimicrobial activity compared to UC and CH.