Dual drug release profiles of salicylate-based polymers and encapsulated chlorhexidine as potential periodontitis treatments

Salicylate-based poly(anhydride-esters; SAPAEs) have demonstrated wound healing properties due to salicylic acid (SA) release during polymer degradation. Additionally, the polymers are deformable and self-adhesive due to their low Young’s modulus, lower glass transition temperature ( T g ), and inherent tackiness at body temperature. These properties make them particularly well-suited for therapeutic use in the bacteria-laden environment of the oral cavity. To enhance their therapeutic capabilities, the antiseptic chlorhexidine dihydrochloride was physically incorporated into SAPAEs for dual release of antiseptic and anti-inflammatory upon degradation. This study analyzes the thermomechanical properties of two SAPAE compositions (adipate homopolymer and 50:50 adipate:sebacate copolymer) and the release of chlorhexidine (incorporated at 10% (w/w)) from these polymers. Polymer adhesivity was monitored as a function of chlorhexidine incorporation and in vitro degradation time. Throughout in vitro degradation, the polymer systems had a low Young’s modulus and a T g at or near body temperature. Incorporation of the antiseptic further decreased Young’s modulus and increased both the T g and adhesivity. The release profiles were also evaluated and determined to be similar for the homopolymer and copolymer, although the homopolymer degradation occurred over a longer time period. Overall, the SAPAE systems have favorable properties for periodontal disease treatments by virtue of their controlled degradability, deformability, adhesivity, and release profiles with encapsulated antiseptic.