Re[2]: Patient dose from dental radiography

[julian.gibbs@mcmail.vanderbilt.edu]

     You are absolutely correct.  The first paper dealing with doses from 
     dental radiology, published in the 40s, multiplied skin exposure by 
     the number of films in a standard full-mouth series, and came up with 
     a total of nearly 50R.  This is why most of us in the dental field 
     prefer to use effective dose (equivalent).
     
     Julian Gibbs


______________________________ Reply Separator _________________________________
Subject: Re: Patient dose from dental radiography
Author:  radsafe@romulus.ehs.uiuc.edu at +inet
Date:    2/13/97 5:37 PM


julian.gibbs@mcmail.vanderbilt.edu wrote: 
> 
> Dose at skin entry for intraoral dental films is now of the order of 1-1.5 mGy
> (sometimes a bit less) depending on projection and beam energy (dentists
> currently use machines ranging from ca 50 to 80 kVp half-wave rectified and in
> some newer machines 60-70 kVcp).  Skin dose from panoramics is difficult to
> specify because of the changing source-skin distance as the machine traverses 
> its prescribed path.
> 
> Julian Gibbs
     
A good note about EDE (below) vs skin entry, but is EDE for a dental 
x-ray like thinking about the "life-shortening effect" of hitting 
(tapping) your finger with a hammer?  :-)  And since dose is e/mass, as 
Vic Bond, John Cameron and others have often noted, the idea of adding 
them is like thinking about adding 1 hit to each finger as 10 hits to 1 
finger? 
     
     
Regards, Jim Muckerheide
jmuckerheide@delphi.com
     
> ______________________________ Reply Separator 
_________________________________
> Subject: Re: Patient dose from dental radiography 
> Author:  radsafe@romulus.ehs.uiuc.edu at +inet
> Date:    2/13/97 10:38 AM
> 
> May I assume that this is skin entrance dose to the jaw? 
> 
> In Message Wed, 12 Feb 97 13:44:38 -0600,
>   julian.gibbs@mcmail.vanderbilt.edu writes: 
> 
> >     Current consensus estimates for effective dose (in some cases 
> >     effective dose equivalent) from dental radiography:
> >
> >        Full-mouth intraoral (ca 20 films)      40 uSv 
> >        Panoramic                               10 uSv 
> >
> >     These values assume state-of-the-art technology: fast screen/film, 
> >     full collimation and filtration, etc.
> >
> >     For details see White SC, Dentomaxillofacial Radiology 21:118, 1992. 
> >
> >    ====================================================================== 
> >     S. Julian Gibbs, DDS, PhD                           Voice 615-322-3190 
> >     Professor of Radiology                                FAX 615-322-3764 
> >     Vanderbilt University Medical Center
> >     Nashville TN 37232-2675    Internet julian.gibbs@mcmail.vanderbilt.edu 
> >     ====================================================================== 
> **********************************************************************
> William G. Nabor
> University of California, Irvine
> EH&S Office
> Irvine, CA,  92697-2725
> WGNABOR@UCI.EDU
> **********************************************************************