Bioactive materials undergo hydration by releasing a number of ions during the setting stage. The reaction on the surface of these materials can release and alter the concentration of dissolved ions, which triggers both intracellular and extracellular responses. This process also leads to remineralization. The released Ca2+ ions increase alkalinizing activity, have a bactericidal effect, suppress osteoclast activity, and stimulate fibroblast formation. The present study aimed to analyze Ca2+ ion release from the bioactive materials MTA-Angelus® and Biodentine®. As many as 46 samples (23 MTA-Angelus® and 23 Biodentine®) were prepared (2 mm in diameter and 2 mm in height). Both the materials were immersed in deionized water for 1 h and 48 h followed by measurement of the released Ca2+ ions. An atom absorption spectrophotometer was used to measure Ca2+ ion release. The results were statistically tested using the Kruskal-Wallis test. The Mann-Whitney post-hoc statistic test showed a significant difference between all the groups (p≤0.05). Biodentine® released more Ca2+ ions compared to MTA-Angelus® at the 1h and 48 h measurements. MTA-Angelus® released Ca2+ ions faster than Biodentine®. © Published under licence by IOP Publishing Ltd.