Final answer:
Before dentin bonding, the smear layer must be removed.
Step-by-step explanation:
Before dentin bonding, the smear layer must be removed.
The smear layer refers to a thin layer of debris that is created on the surface of dentin after it is cut or prepared for dental procedures. It consists of microorganisms, dentin debris, and organic and inorganic substances.
Removing the smear layer is important for successful dentin bonding because it allows for better adhesion between the dental material and the dentin surface.