What about untreated air?
All reputable dental compressor manufacturers have systems that produce air of the standard
required for Dental Air, which is the International Standard ISO 8573-1: 2001
Quality Class 1.4.1.
The main failures experienced in dental practices are attributable to the inadequate capacity
of the air supply and water vapour removal.
Some practices are still using oil lubricated compressors with no or limited filtration and no
or limited moisture removal systems. These air systems are definitely not fit for purpose. Untreated air from
oil lubricated air compressors presents two major areas of concern.
How not to do it.
Firstly there is the quality of air to which the patients and staff members are exposed.
Without treatment, this air can carry a high level of hydrocarbon contaminants, moisture and biological
material (active and inactive). When mean air temperatures are high, bacterial and fungal growth in air lines
and receivers is a consideration. This has two main implications; the effect on the patient and staff
breathing this air and the chemical and biological effects on clinical restorative, preventative and
aesthetically involved procedures i.e. bonding etc. Concerns also arise from the possible introduction of
Legionella sp. and similar type pathogens into the air system from sources developing in warm moist receiver
Secondly, there is the effect of hydrocarbons, particulate matter and water on the functioning
and degradation of the equipment which effects day-to-day reliability and service life.
An obvious question that arises from this information is why use oil lubricated compressor
when oil free compressors eliminate the hydrocarbon contaminants. In our experience, oil free compressors
have a much reduced service life when operating at high ambient temperatures and usually the manufacturer’s
warranties are made void if air intake temperatures are above 40 deg. C (This is often experienced in outdoor
and poorly ventilated enclosures). In the tropics if your compressor is to be housed externally i.e. outside
an air-conditioned air space, then for longevity of service, an oil lubricated compressor is recommended if
you have the space for it and fit the necessary air treatment components.
Your air system should look something like
Pictured is an Oil lubricated rotary scroll air system with refrigerated dryer, suitable air
filtration and a redundant spare compressor on stand by. This type of installation guarantees that there will be no
surgery down time due to loss of air supply.