POLYDIMETHYLSILOXANE‐BASED CEMENTS CONTAINING CALCIUM BIOCERAMICS AND BIOGLASSES WITH ENHANCED BIOACTIVITY

Vibrational IR and Raman spectroscopies were successfully used to characterize at a molecular level a calcium bioglass containing commercial cement based on polydimethylsiloxane (PDMS), i.e., GuttaFlow Bioseal, used as root canal sealer in endodontics. Its bioactivity was compared to GuttaFlow 2 (a similar commercial PDMS‐based cement, but without the calcium bioglass) and its doped variants containing 20% w/w dicalcium phosphate dihydrate (DCPD) or hydroxyapatite or a tricalcium silicate‐based cement.Ageing tests in Hank’s Balanced Salt Solution (28 d, 37 °C) showed that GuttaFlow Bioseal was the most bioactive cement, thanks to the formation of a silica‐rich layer with nucleation sites for the deposition of a B‐type carbonated apatite. This phase appeared thicker when the material disk was aged in the presence of a guttapercha cone, i.e., under conditions more similar to those clinically available, with the two materials influencing each other.The doped types of cement showed higher bioactivity than simple Guttaflow 2, suggesting that the particles of the mineralizing agents are spontaneously exposed on the cement surface. However, the hydrophobicity of the PDMS matrix slowed down apatite deposition.