Suction units in dental technology
(German: Absauggeräte in der Zahntechnik)
In the dental laboratory suction units remove
harmful fumes and dust from the air. This also avoids contamination
of materials, equipment and instruments.
Electrically operated extractors are used as single, dual or
multiple units as well as laboratory suction units for use at
many technical workstations or dust-generating machines such as
sandblasters or polishing motors. Suction units are in principle
differentiated between “dry suction” (e.g. for sandblasters) and
“wet suction” (e.g. for dental laboratory turbines). Generally,
the aim is to position the suction as near to the location where the
dust is generated as possible. In addition to the more common
stationary units, mobile versions are also available.
Suction units have the following technical components:
- The motor produces the suction, the intensity of which is
given as “volume flow” (“standard cubic metre” or “standard
litre” per unit of time with standard values for pressure,
temperature and moisture). It is – in particular due to frequent
switching on and off – exposed to high stress, which often
results in only a low service life (= number of operating
hours). Intelligent controls not only allow selection between
continuous operation and operation as required (automatic switch
on with the respective working unit) but also settings to suit
- Depending on the configuration of blower/ventilator in
relation to the motor, the unit is described as a negative
pressure or positive pressure system.
- Extracted particles are gathered in a collector (e.g. in
the form of a dust bag).
- Various filters with several different “filter classes” are
particularly important for keeping the air clean. Coarse and
fine dust filters retain particles with a diameter of between 1
µm and in excess of 10 µm; fine dust filters
(particle size < 1 µm) with a filtration
efficiency of over 99.9% also filter smoke, bacteria and
aerosols. In addition to the mechanical filter function,
active carbon filter also have a
chemical cleaning effect due to adsorption and/or reduction.
- The actual suction is created via a suction hose, suction
tube or suction channel terminating directly at the dental
laboratory workstation from a chamber, which is sealed from the
external environment (e.g. blasting chamber of a sandblaster) or
open, e.g. with a “suction cup”. A suction box that can
be connected to the extractor prevents contamination of the
remaining working environment and enables the suction effect to
be focussed more accurately.