I haven't seen the entire discussion on canker sores, but I
get the impression that most explanations center on cooking.net">food
sensitivities or on herpes virus.  My boyfriend claims that
he never had any canker sores until he met me; I've had them
on occasion (not unusually often) all my life.
   Is is possible that the herpes virus, which is contagious,
causes a greater predilection for cooking.net">food sensitivity?  I.E., both
factors are necessary to cause a sore?  
   Or doesn't anyone really know?

About half the articles I have read on canker sores describe them as
aphthous ulcers and don't mention herpes simplex.  The other half
describe them as herpetic.

What's the current received wisdom on the subject -- are they:

    1.  Always herpetic
    2.  Sometimes herpetic
    3.  Usually herpetic
    4.  Never herpetic

And is there any difference in morphology or natural history between
those that are herpetic and those that aren't.

It strikes me as a non-trivial question, because if canker sores are
always or generally herpetic, then ought one not to take precautions
against infecting others who do not have them and/or {*filter*} partners?
And, for instance, if two individuals who both have canker sores have {*filter*}
sex, do they risk spreading an infection to the {*filter*} region?
--
Sarge Gerbode -- UUCP:  pyramid!thirdi!metapsy!sarge
Institute for Research in Metapsychology
431 Burgess Drive; Menlo Park, CA 94025

Canker sores of the common variety are not herpetic (at least herpes
can't be cultured from them).  I don't think anyone really knows what
they are, whether viral or not.  They do not appear to be contagious.
Stress or biting the lip can precipitate them.  They occur on the
inside of the mouth, whereas herpetic lesions usually occur on the
outside of the lip.  If in doubt, most dentists can tell you which
kind you have (they definitely want to wear gloves to work on someone
with a herpetic lesion, although nowadays, because of aids, most
dentists wear gloves anyhow).  I am not an expert in the field but
have read some about it because I am subject to the canker sores from
time to time.

I think the fact is that no one knows for sure what the answer is to your  
question.  Since canker sores resolve spontaneously in 10-14 days in most  
cases, it commonly is thought that whatever the last treatment was, was the  
cure.  Hence, the genesis of the disease is decided in part by what worked.  
There is a list of probably 100 treatments for canker sores, all of which were  
thought by someone, at some time, to have been effective.  I sure didn't have  
any luck with the Zovirax, or the silver nitrate, or swabbing with merthiolate,  
or tincture of myrrh, or alum in its various forms.  When they're ready to  
leave, they go.  Quite a mystery and won't we all be delighted when some clever  
scientist solves it for us!!

--  
Uucp: ...{gatech,ames,rutgers}!ncar!asuvax!stjhmc!231!80.0!John.Moe