Tooth deposits

A clean tooth surface exposed to the oral environment rapidly accumulates an amorphous protein film called pellicle. This deposition has been attributed to the instability of salivary proteins, and to the surface characterics of apatite.

The pellicle is soon colonised by bacteria to form plaque. The initial microorganisms are mainly gram positive cocci. Some of these bacteria synthesise extra-cellular polysaccharides, which enable them to adhere to the pellicle and provide resistance to subsequent displacing forces.