Background Knowledge: Calcium hydroxide with a pH of almost 12.5 is a strong alkaline substance. In an aqueous solution, dissolution of calcium hydroxide occurs into calcium and hydroxyl ions. Its biological properties include antimicrobial activity, inhibiting resorption of tooth and inducing of repair by formation of hard tissue. Hence it is widely used in several clinical situations.
The capacity of calcium hydroxide to produce an alkaline shift in pH is responsible for its antimicrobial effect. This property will be affected when it is combined with other substances/ vehicles like 2% chlorhexidine, sodium hypochlorite etc, which makes the action last longer.
Therefore this study was conducted to determine the changes in pH of five different types of calcium hydroxide based intracanal medicaments.
Materials and methods: This study assesses the changes in pH when calcium hydroxide is mixed with different vehicles like 2% chlorhexidine, sodium hypochlorite, povidone iodine and also commercially available RC Cal (premixed) and Metapex. It is an in vitro study with time intervals of 24 hours, 48 hours and 1 week.
Results and conclusion: Within the limitations of the study, it is found that calcium hydroxide when mixed with distilled water has given the best results.
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