A novel binary chlorhexidine-chitosan irrigant with high permeability, and long lasting synergic antibacterial effect.

Objective: Chlorhexidine gluconate (CHX) is an irrigant with a  reasonable antibacterial ability and rather high permeability yet often fails to remove the smear layer. To solve this problem, CHX is upgraded through its complexion with chitosan (CS). Methods: Molar roots are split longitudinally by a rotary diamond saw. Chlorhexidinechitosan (CHX-CS) is made by combination of CHX 2% and CS and adding Glutaraldehyde (GA) as a linker agent, followed by a freezedrying process. Results: For the first time, CHX-CS is synthesized through linking of CHX and CS with GA. Subsequently CHX-CS is fully characterized with FTIR (Fourier transform infrared spectroscopy), SEM (Scanning electron microscopy), DLS (dynamic light scattering), and antibacterial and water wettability tests. Significance: Ournew CHX-CS complex synergically preforms the advantages of both CHX and CS. Specifically, permeability and bactericidal effects of CHX are effectively coupled with CS smear layer removal capacity. Ease of synthesis, biocompatibility, better penetration, higher antibacterial activity, and economic benefits of this complex invite its dentistry and endodontistry applications.