A novel methodology for controlled-release antimicrobial system in endodontic sealers -

Abstract

Introduction: Current endodontic sealers have limited antimicrobial effect after root canal system obturation that deteriorates over time. Objectives: The aim of this in vitro study was to investigate the ability of a new system to provide extended antimicrobial properties to endodontic sealers by controlled-release of Iodine. Methods: Seven dilutions of Iodine to double distilled water (1:0, 0:1, 1:1, 1:2, 1:4, 1:9, 1:19) were chemically linked to ethyl cellulose particles to form iodine/ethyl cellulose complexes. Two different classes of commonly used endodontic sealers: Calcium Hydroxide based sealer; Sealapex (SA; Sybronendo), and Zinc Oxide-Eugenol based sealer; Pulp Canal Sealer EWT (PCS; Sybronendo) were mixed with the complexes and dispensed into Teflon molds to form sealer discs. Each disc contained 5% by weight iodine/ethyl cellulose complex particles. Samples (n=80) were divided into two groups and suspended in Brain Heart Infusion broth for 24 hours (SP1) and 7 days (SP2). The antimicrobial activity against Enterococcus faecalis was tested by measuring the absorbance values of broth after inoculation for each test group and controIs. Results: Our results confirmed that the antimicrobial efficacy of sealers tested is enhanced by the addition of higher concentrations of iodine in ethyl cellulose complexes when compared to controls. The ability to inhibit bacterial growth is also enhanced over time. (SA) group had statistically significant difference for (1:0) group at SP1 and (1:0, 1:1, 1:2, 1:4, 1:9, 1:19) groups at (SP2) when compared to control. (PCS) had statistically significant difference for (1:0, 1:1, 1:2) groups at (SP1) and for (1:0, 1:1, 1:2, 1:4, 1:9, 1:19) groups at SP2 when compared to control. Negative control groups (0:1) had the highest mean absorbance values. Conclusion: Within the limitations of this study, the addition of higher concentrations of iodine/ethyl cellulose complexes to endodontic sealers results in higher antimicrobial activity over time against Enterococcus faecalis.