Why keep dentures in water?

[Ankur]

I've been told that constant hydration/dehydration of acrylic may
result in a dimensional change, but I can't find any evidence to say
whether this happens or whether it is clinically significant. Have
there been any studies? Are there other reasons to keep acrylic
dentures in water overnight?

--
Ankur

[Bill]

"Ankur" <an...@lipidity.com> wrote in message

George Washington's false teeth have not been kept in water and look
at how nasty they look!
http://www.flickr.com/photos/63021824@N00/403876953/

[Steven Bornfeld]

Dimensional change due to dehydration was pretty much accepted as
gospel, and I don't remember ever being given references.
However, it happens that there IS evidence of dimensional change with
dehydration of acrylic resin bases. This study touts the superior
dimensional stability of polycarbonate for denture bases. Too bad
polycarbonate is no longer used in beverage containers due to toxins
leaching out.

http://www.ncbi.nlm.nih.gov/pubmed/14641656

Steve

--
Mark & Steven Bornfeld DDS
http://www.dentaltwins.com
Brooklyn, NY
718-258-5001

[Steven Bornfeld]

That's not bad. They actually look like human teeth. Do they credit
the dentist? Traditionally, it's said that Jonathan Greenwood was his
dentist. But I've heard that one of Washington's sets of dentures may
have been made by Paul Revere.

[Ankur]

* Steven Bornfeld <bornfe...@dentaltwins.com>
> ... there IS evidence of dimensional change with dehydration of
> acrylic resin bases.

Thanks for that reference. That study measured dimensional change
after 7 and 30 days of dehydration, so it seems to support long term
storage in water.

I'm also interested in the effect of leaving it out of water
overnight; if, say, 10 hours a day out of water doesn't cause
significant distortion, then leaving it out might help reduce the
probability of Candida getting into the denture.

I'll investigate some more and post back if I find anything
interesting.

--
Ankur

[Steven Bornfeld]

Don't you think the candida usually comes from the denture into the
water, not the other way around?
Kidding. I actually have had patients who've dried out their dentures
and I honestly can't say I've ever seen significant dimensional change
where retention is affected. But I still tell patients to keep their
dentures wet. And the labs always deliver the finished dentures in a
bag with water in it.