(PR19) Quantitative Analysis of Polymerization Kinetics and Cohesive Strength of a Resin-based Liner When Used with Bioceramic Materials

Abstract: Following a perforation repair, a proper seal is essential to a successful outcome. To evaluate the polymerization kinetics and the cohesive strength of a resin-based liner (BC Liner) for bioceramic materials. BC Liner (BCL) in shades White and Blue, and Fuji LC II (Shade A2) were used as control. Degree of conversion (DC) and the maximum rate of polymerization (RpMax) were measured (n=3) at 10 min and after 48 hours. Cohesive strength (CS) and modulus (CM) (n=12) were evaluated using hourglass-shaped specimens in a universal testing machine at 10 min and 48 hours after cure. A VALO LCU (1000 mW/cm2, 20 seconds) was used for the photopolymerization. Statistical analyses were performed using ANOVA and Tukey’s test (α=0.05, β=0.2). BCL had a lower DC and RpMax than the Fuji LC II. At 10 min, no differences were found on the CS between the BCL and Fuji LC II. After 48 hours, the BCL had higher CS than Fuji LC II. BCL had lower CM than Fuji LC II. BCL showed a high CM at 48 hours compared to the 10-minute reading, but both were lower than Fuji II LC. No significant differences were found between BCL White and Blue.

Conclusions: BCL has slower polymerization kinetics and similar CS than Fuji LC II at 10 min. After 48 hours, BCL has higher CS than Fuji LC II. BCL can substitute Fuji LC II as a liner material over bioceramic materials in endodontic treatment to minimize potential leakage.