The evaluation of setting time and FTIR spectroscopy of carbonate apatite cement as endodontic sealer

The carbonate apatite (CO₃Ap) cement as an endodontic sealer plays an essential role inendodontics treatment due to its potential to obturate root canal system as one of the most important parts in endodontic treatment. Moreover, the CO₃Ap has the probability of similarities with a composition of root dentin. Recently, the setting time of commercial endodontic sealer has 4 hours to 1 day. Therefore, the aim of this present study is to evaluate setting time and to determine the functional group of the new material composition for endodontic sealer. CO₃Ap cement sealer was prepared by mixing dicalcium phosphate anhydrous (DCPA), vaterite and calcium hydroxide [Ca(OH)₂] with 0.2 mol/L Na₂HPO₄ containing 1% sodium carboxymethylcellulose (NaCMC) and 32 µg thymoquinone, with liquid to powder ratio of 0.6. The setting time was evaluated by Vicat needle method as describe on modification ISO 1566 for zinc phosphate cement. Five compositions of powder ratio were prepared in this study. The set CO₃Ap cement sample was evaluated by Fourier Transform Infrared Spectroscopy (FTIR) to define the functional group of the sample. Setting time evaluation indicated that the average setting time of CO₃Ap cement was 21 minutes of five compositions. The FTIR analyses revealed that the CO₃^2- groups were detected, so the results could determine as B-type CO₃Ap. The CO₃Ap cement was considered fast setting as an endodontic sealer compared to sealers made from other base and proven to have similarities with the components of root dentin.