BACKGROUNDThis study aimed to develop an orthodontic cement containing chitosan and 2-methacryloyloxyethyl phosphorylcholine (MPC) and to investigate its antibacterial properties and biocompatibility.METHODSChitosan and MPC were incorporated into commercial cement. The enamel bonding strength and biocompatibility of the new cement were evaluated. The antibacterial properties were assessed by examining biofilm metabolic activity and colony-forming units (CFU). An evaluation of the protein repellency of the cement was also conducted.RESULTS The new cement containing chitosan and MPC had clinically acceptable bonding strength. In comparison to the control, the novel cement demonstrated enhanced protein-repellent properties (p < 0.05), inhibited biofilm metabolic activity (p < 0.05), and reduced CFU counts (p < 0.05) without diminishing cell viability in response to cement extracts (p > 0.05).CONCLUSIONSThe synergistic application of chitosan and MPC endows the cement with potent antibacterial abilities, protein repellency, and favorable biocompatibility.