The main measures limiting the spread of the infection at a dental appointment are aseptics and disinfection with antiseptics closely related. Key notions in this sphere are as follows.

Aseptic means the state of being free from disease-causing contaminants (such as bacteria, viruses, fungi, and parasites) or preventing contact with microorganisms.

Antiseptics means all you have to do in order to destroy microorganisms in injury, organs and tissues.

In 1890 at the Xth International Medical Congress in Berlin the basic postulate of asepsis was adopted: all things that come in contact with injury must be sterile.

There are high degrees of pollution and microbial contamination; besides, dental instruments are of rather complex configurations, lots of retention points and locking fasteners. Besides there is a great variety of dental instruments and each one of them has a specific function, structure of materials. That is why the choice of ways and methods of disinfection and sterilization requires a differentiated approach.

Disinfection means destruction of most pathogenic and other kinds of microorganisms (but not spores) by physical or chemical means.

Sterilization means a physical or chemical process that destroys all microorganisms, including spores.

In 1968 E.H. Spaulding suggested dividing all medical products into critical, non-critical and semi-critical items based on the degree of contact they have with patients and their risk of disease transmission. In turn, their risk of disease transmission indicates how they should be cleaned for reuse.

Critical items cut bone or penetrate soft tissue. These instruments carry the highest risk.

Clean and heat-sterilize critical dental instruments before each use.