Dental Management

Posted: 20 February 2012

Infection control: Dental unit waterlines (Part II)

Author: Carmel Maher

In part two of her feature on dental unit waterlines, Carmel Maher describes a highly effective system that will virtually eliminate bacteria

The previous article in this series (see end of article for link) looked at the potential dangers attached to the use of contaminated water in the dental surgery. The subject of DUWL contamination has received much attention in recent years and several research papers and clinical articles have highlighted the risks to patients, clinicians and practice staff.

This article will describe how Optident Sterilox can provide potable water for use in dental unit waterlines that use closed bottle systems.

Optident Sterilox is a safe and fast acting effective broad spectrum biocide. It is produced by the conversion of an electrolytic solution into hypochlorus acid, which is reported to be many times more effective than hypochlorite (bleach), when used as a biocide¹.

The super-oxidised solution successfully reduces the level of colony forming units (CFUs) in water, from thousands to virtually zero².

A neatly designed generator (Figure 1), enables this conversion to take place, using electrolysis. The Sterilox generator can be sited on any convenient worktop, and allows the immediate dispensing of Sterilox solution on demand.

In use

Sterilox is a completely safe solution, and does not involve the use of any toxic chemicals. Being non-irritant and non-aggressive, it is not harmful when in contact with the skin. It does not require the use of additional protective clothing, eyewear or equipment and there are no special precautions attached to its disposal.

When using Sterilox in DUWLs, it should be diluted with tap water, (min 2% Sterilox / 98% water). It can then be used in closed bottle dental unit water supplies, initially as a purging agent and afterwards as a method of maintaining a clean, potable water supply (Figure 2).

To achieve successful initial purging of already contaminated DUWLs, it is recommended that concentrated, non-diluted Sterilox solution be used. Sterilox is extremely versatile, and can be used as a disinfecting solution, in which conventional dental impressions can safely be immersed without any adverse effects to their surface or overall stability. A 10% solution can be used, and impressions should remain immersed for 10 minutes (Figures 3 and 4). The solution is also effective as a hard-surface disinfecting agent and can be used in much the same way as proprietary disinfectants.

In the surgery

To create the Sterilox solution, the generator must first be filled with the electrolyte solution. The electrolyte solution has been specifically developed for dental use, and is the only one that should be used. A one gallon container will provide sufficient Sterilox to fill approximately 175-250 DUWL bottles. Having filled the generator, it is only necessary to depress the panel switch at the front of the generator to produce Sterilox solution immediately (Figure 5).

Conversion is effected by use of a proprietary electrochemical cell within the generator (Figure 6). The solution is then collected in a calibrated plastic container, which can assist in measuring correct dilution levels.

It is recommended that the strength of the Sterilox solution be checked regularly using test strips that are dipped into the solution. These are similar to litmus paper and can be checked against a colour comparison chart that will indicate the strength of the solution.

To measure the effectiveness of Sterilox in reducing bacterial contamination, it is suggested that use be made of dip slides. These are available from Optident and allow a simple ‘before and after’ check to be made of the water quality.

Initial checking of DUWL water supplies will invariably show a heavy colony forming unit (CFU) presence, but after initial purging and routine use of Sterilox in the system, they will show virtual elimination of CFUs after only a few weeks.

By using Sterilox dental practitioners can be assured that they can virtually eliminate the risks that are attached to the use of contaminated water supplies in their dental units, therefore contributing to a safer working environment for patients, clinicians and dental practice staff.
 

References

1. Martin MV, Hypochlorus Acid - A new potential for dentistry, Dept. of Clinical Dental Sciences, Univ. of Liverpool, Dentistry, Nov 2003

2. Martin MV, Gallagher MA. An investigation of the efficacy of superoxidised (Optident Sterilox) water for the disinfection of dental unit water lines, British Dental Journal, March, 2005:198(6) pp353-354