Architectural organisation

The functioning of a dental surgery requires organisation as well as rigorous ergonomic control. Indeed, it is necessary to organize not only the circulation of the staff and patients but also that of the instruments and other medical equipment. This circulation is much more difficult to manage when the surgery is situated in the midst of a former residential area, modified for professional use.

The circulation of patients must be as simple as possible in order to promote hygiene and asepsis. The existence of a room specifically for surgical procedures facilitates the organisation of the practitioner's work, the patients passing through an « airlock » (or intermediate room) between the waiting area and the treatment room.

Circulation of the medical equipment

It is difficult to avoid conflicting pathways for the sterile medical equipment, the soiled equipment and patients. The ideal objective is to organize a « one way » circulation between the different areas for patients, as well as for the medical equipment that has to be dealt with (decontaminated and sterilised). However, the architectural arrangement of surgeries may not always permit the ideal circulation of patients, soiled equipment and sterile equipment.

In order to achieve a satisfactory asepsis chain, it is necessary to adopt a pathway that can provide an adequate substitute for an ideal circulation (^{Missika and Drouhet, 2001}) :

- the distance that soiled instruments have to be taken between the dental chair and the sterilisation room must be as short as possible. It must be logical and rigidly enforced ;

- at the end of the treatment, all the used instruments are immediately plunged into a decontamination bath containing a standard disinfectant. This can be either directly in the surgery or in an adjoining room ;

- the instruments are then brought to the sterilisation room where they will undergo cleaning and drying (wet room). They will then be prepared for sterilisation (dry room) ;

- storage of the sterile instruments packs should be close to the workstation or dental unit, in drawers or clean cupboards and protected from light.

Control of the environmental infection risk

The concept of risk assessment allows us to classify rooms to a required level to ensure a stringent regime of hygiene.

The risk of contamination by a potential infectious agent depends on of the room in which one is.

In the hospitable environment, different zones are distinguished according to the potential for infection risk (^{Darbord and Dauphin, 1988}). One can establish the same type of classification for the dental surgeries (^{Perrin et al., 1997}).

Classification of zones in the surgery and the treatment required

This classification differentiates three zones as below :

- zone 1 includes the corridors for general circulation, from the entry, to stairs, surgery, waiting room, etc. ;

- zone 2 groups together the sterilisation room and consulting rooms ;

- zone 3 includes the room for surgical interventions and the toilets.

The treatment required for zone 1 is similar to daily domestic cleaning. It is the starting zone for cleaning. Sweeping with a damp mop is undertaken prior to using a detergent.

In zone 2, the treatment required is daily « biological cleaning », alternating between detergents and detergent-disinfectant products.

Finally, for zone 3, the treatment required is also daily (or more frequent) biological cleaning. This biological cleaning must be done before and immediately after surgical interventions. The creation of a room specifically for surgical interventions allows the necessary « rest » time for the disinfectant to act, normally 20 minutes.

When a dedicated room does not exist, surgical interventions are undertaken in a room that is classified as zone 3 and it is advised to reserve a period of time for biological cleaning before and after each surgical procedure. This includes the « rest » period and should by preference be the first hour of the morning.

Realistic biological cleaning

« Biological cleaning » is a method used to reduce the contamination of surfaces and floors. Essentially, it involves zones 2 and 3. Its efficiency depends on five conditions :

- cleaning should progress from clean to dirty and from top to bottom ;

- it should have a mechanical action ;

- it should involve the use of a standard product with a chemical action ;

- the cleaning action should be enhanced with heat ;

- ensure an adequate contact time, according to the product being used.

There are three stages to biological cleaning :

- removal of clinical waste ;

- mechanical and chemical cleaning with a detergent ;

- application of a disinfectant.

BIBLIOGRAPHIE

• Darbord JC, Dauphin A. Hygiène hospitalière. Paris : Édition médicale, 1988.
• Missika M, Drouhet G. Hygiène, asepsie, ergonomie, un défi permanent. Paris : Éditions CdP, 2001.
• Perrin D, Pacaud G, Pône D. Contrôle du risque infectieux en odontologie. Paris : Éditions CdP, 1997.