Introduction Cavity liners based calcium hydroxide present low strength and high solubility that is consider a disadvantage. In order to enhance these properties it was developed a light-cured cavity liner based calcium hydroxide containing resin. Objective The purpose of this study was to evaluate the pH and calcium release of light-cured cavity liners. Material and method There were prepared specimens (n=10) with the Ultra-Blend ® plus, Biocal® (light cured cements) and Hydro C® (control). The samples were stored in 10 mL of distilled water and maintained at 37 °C. After 24 hours, 7, and 14 days, there were analyzed pH and the release of calcium levels. The data were statistically analyzed by ANOVA and Tukey test (α = 0.05). Result The results of pH showed Hydro C > Ultra-Blend plus > Biocal. Biocal presented worst calcium release. Conclusion Light-cured materials present lower calcium release and alteration in pH values.

Introduction If the restoration, that seal the root canal from oral environment, failed or solubilize, the intracanal dressing could be partially removed, decreasing the efficiency of calcium hydroxide (CH). Objective To evaluate the alkalizing potential and calcium ions release of intracanal residues from different medications, in different periods. Materials and method Human incisors were endodontically instrumented and randomly divided (n=10). The root canals were filled with: G1⎯Calcium hydroxide (CH); G2⎯CH with 0.4% chlorhexidine digluconate (CHC); G3⎯CH with camphorated paramonochlorophenol and glycerin (HPG); G4⎯CH was maintained during all experiment, as positive control group (PC) and G5⎯ No medication was performed in the negative control group (NC). The specimens were immersed in distilled water for 7 days. The intracanal dressing was removed from the experimental groups using F1 instrument (Protaper). The teeth were stored in distilled water for 24 hours, 7, 14 and 28 days. pH value and calcium ions released were evaluated and the data were submitted to ANOVA one-way and Tukey tests. Result All experimental groups presented lower alkalizing potential and calcium ions release than PC (P<0.05). No significant difference was found among the experimental groups, regardless of the period (P>0.05). Conclusion The alkalizing potential and calcium ions release of residues from different intracanal dressing, in different periods, were similar and lower than the positive control group, that the medication was maintained inside the root canal, encouraging the replacement of intracanal dressing when the restoration fail.