Marvin Goldmans comment on usefulness of dental x-rays

["Franz Schoenhofer" <schoenho@via.at>]

Schoenhofer
Habichergasse 31/7
A-1160 Wien
AUSTRIA
Tel./Fax: +43-1-4955308
Mobiltel.: +43-664-3380333
e-mail: schoenho@via.at

You wrote:

> 1.	 Since I was at my dentist today, I repeated this story to him and
> asked if insurance companies really require radiographic documentation.
> Answer was no.  Documentation was requested only in cases of payment for
> one therapy strategy vs another which had a different cost.  But never on
> whether dentures were needed for someone gumming their way through life.
> Usually a letter is the only documentation needed.  He never heard of
> requiring an x-ray to document an adental mouth.  I'd never permit it if
I
> was the patient!  Not because of radiation risk, but because of common
> sense.
> 
> 2.	The ranting on low level risks seems never to abate.  We all know
> that the science of molecular biology still has given us no direct proof
of
> cancer risk (and it's only cancer risk in this debate), even though some
> induced genetic and molecular markers in today's literature may be steps
on
> the way to a full understanding of all the mechanistic pathways and steps
> from dose absorption to cancer manifestation.  Nor can anyone with any
> understanding of epidemiology expect that epidemioogical approach can
ever
> show the risk from millirem sized doses even if the ICRP coefficients are
> correct.   When it come to a religious belief level of discourse, rather
> than objectiviely  interpreting a science data set, we all lose
> credibility.
> 
> 	The absence of "bodies in the street" proves nothing when dealing
> with minute probabilistic risks.  For what it's worth, I have no problem
> with the linear, no-threshold hypothesis as a model for regulatory
policy.
> I do have a problem with those who selectively plot data points along a
> straight line and insist that it confirms the linear proportional risk
> coefficient down to the last photon.  Counting "hypothetical bodies" at
> microSv exposures is a way to play with collective doses, but it's not
real
> nor realistic.  Biology  just does not work that way, and in due course
the
> window of insight will open.  Sadly, support for the research to speed up
> the opening of that window is limited, so we may have to be patient. 
Until
> then, I for one am satisfied with the conservative LNT philosophy, but
not
> the further subfractionation of the limits to ridiculous  operational
micro
> compartments.  As for the "true risk", to me at this time, the universal
> curve of risk still looks sigmoid, with the region from about 0.1-0.2 Sv
to
> 1-3 Sv appearing to be fairly linear.  Period!
> 
> 	I realize that each of us has an opinion, that most are not ready
> to change their opinion, and that  if the data were really there, this
> issue might actually be settled, (if an issue can be said to ever be
truly
> settled).  It's not a matter of being an "old man worried that he might
be
> wrong", but whether the cold scientific data are tight enough.  To which
> this old scientist says the data are good, but still not tight enough.
I'd
> welcome seeing an increase in the research dollars rather than
substituting
> an increase in reactive decibels.  But then I'm only one voice.
> 
> Marvin Goldman
> mgoldman@ucdavis.edu
> 
> 
Marvin,

Thanks for this comment, you are not only one voice in this context. Many
scientists dislike the attitude of "green" groups, to make any pSv/y and
uSv/y a catastrophe, but I think (hope) that as many scientists dislike the
attitude to make any mSv, Sv a ridiculous low event, which should almost be
enforced. As long as we have no better insight the opinions of
international (from governments independent) bodies should serve as a
guidance. It is so easy to avoid unnecessary exposure of the average
population and the unnecessary dental x-raying is one of the best examples
for potential of exposure saving. 

A few years ago a German magazine published an investigation about the
number and the quality of x-rays and CT´s taken in different European
countries. The result was clear: in countries where insurances paid most
for x-raying the number of x-rays taken was top. I hope that nobody wants
to justify this with an increased medical need in just these countries. It
might be hard for some radiation protection people, but the dose to the
common population from medical application might not always be related to
radiation protection and medical considerations.

Franz