Acquired pellicle is present on the surface of the tooth within seconds of tooth eruption or cleaning. The pellicle is composed of conditioning molecules in the saliva, gingival crevicular fluid, and produced by bacteria present in the oral cavity. Examples of molecules in the pellicle are biologically active proteins and glycoproteins. It is NOT plaque or a biofilm in that acquired pellicle lacks attached bacteria and EPS (extracellular polymeric substances).