Uh Oh, I have been buying potentially dangerous stuff again
I have just taken delivery of a Philips/Gendex Oralix AC 65S Dental X-Ray System, complete
I could not resist the unit because it comes with everything except the often missing Collimator tube. Not fussed about that as it is easy to build and of little use in my application anyway (it tightly contains the beam to minimise the X-Ray dose to which the patient is exposed. It is not my intention to ever be in the beam when the unit is operating !
This system design has been around a good many years and is a pretty good basis for experimentation. It is compact, relatively light and simple to operate. Maximum exposure level is safety limited to 3.5 Seconds and normal exposures are up to 2.5 seconds. The head runs at a fixed 65kVp with 7.5mA current through the tube. the output is filtered with aluminium to remove the soft X-Ray content. You can see the filter at the centre of the output port in the attached picture.
These units were originally named the Dens-O-Mat and made by Philips. They went on to be manufactured by the venerable Gendex of Milan, Italy. The controller bears the name Dens-O-Mat yet the head is named the Oralix
Mine is the 65kVp version as already stated and so the ID is '65S'. Such systems still command relatively high prices on the secondary market. You are lucky to get a working one complete will all parts, in the UK, for less than £1000 ($1500). Repairing a faulty Oralix head is not something I would recommend. Messy and difficult. Another bit of good fortune is the fact that the user and service manuals are available for free download on the internet. Good for if/when things go wrong
I won this one for a more budget friendly £237 via an e*ay auction
it was delivered by the seller in a Mecedes so no risk of transit damage. This is something to be considered when buying dental X-Ray heads...... they tend to be fragile and do not travel well if dropped !
The unit that I have purchased is the free standing version so it has a trolley rig that supports the articulated arm and associated X-Ray generator head. Its all counter balanced by strong springs in the arms so the head is light as a feather to move around. I will attach a picture of the full system that I found on the web. I have yet to put my trolley together. It all looks in very good condition and I believe the Oralix head is newer than the rest of the rig. The build date is 2005 yet the box shipping label states 2011. (Old stock ?) Either way, the head is in great condition with no damage.
It goes without saying that a dental X-ray head comes with some serious health and safety issues as there is no beam containment and and no safety interlocks to shut the beam off if a person walks into it by accident. As such, this is not a toy. It has to be used in accordance with Dental X-Ray best practice and this is easily found on the web. The room in which it is deployed must be a controlled space to prevent the innocent wandering in and being irradiated. The beam must not illuminate areas that contain life, including pets. In some cases the room is lead lined to meet this criteria. The user of such equipment must be educated in safe usage of such open site equipment (I am formally trained for using such equipment). The use of such equipment for experimentation can lead to accidental illumination of the user. For this reason I highly recommend that the user is either X-Ray badge monitored or equipped with a quality X-Ray dosimeter that works at <45KeV (Kev is less than kVp due to losses). OK that is the warning bit, I have to say it as these units are potentially bad for your health if misused and I wouldn't wish that upon you dear reader.
I will be taking the covers off of the units but the head is pretty uninteresting as it is basically a lead shielded cylinder with only the connections visible. I shall not be dismantling this perfectly good X-Ray generator any time soon. The control panel is not just a single timer. It contains the 'warm-up' phase pulse generator and a multi setting pre-set timer that can have its timings globally adjusted to suit the patient age and film speed. There is only the controller and the head in this system. No external power supply unit or other messy parts needed.
I intend to use this X-Ray generator in experiments illuminating various X-Ray intensifier screens whilst observing the performance via CCTV. I will also be experimenting with image capture using digital cameras and specialist analogue cameras designed for the task (Ex EOD equipment).
I may also be doing some tests on Geiger Muller tubes and meters but that is a low priority for me.
An open site X-Ray generator can be very useful if you have the correct environs and a suitable mobile detector plate. I lack the latter at the moment so will be developing my own using intensifier and electronic camera techniques.
Pictures of unit (as received) attached.
Aurora