Page 524 - My FlipBook

;

52fj

Mr. Blake observes,* " The tooth-powders commonly sold,
consist in a great measure of the cream of tartar, by the use
of which, I have seen the teeth completely deprived of iheir
cortex striatus, and the patients rendered quite miserable ; for
the bony part of the tooth in such cases, becomes sen-ible
to the slightest touch, and also to the slightest changes of
temperature in the atmosphere, or other fluids received into
the mouth. Cream of tartar alone, has been recommended
by Mr. Hunter as a tooth-powder, because, as he says, at
the same time that it acts mechanically, it has likewise a
chemical power, and dissolves this adventitious matter."!
To ascertain the bad effects of cream of tartar as a tooth-
powder, I made the following simple experiment, which will
at once explain how very detrimental the use of it must be,
even in the smallest proportion. I placed a tooth in a solu-
tion of cream of tartar and water, and allowed it to remain
in it for about twelve hours. When taken out, I observed that
the surface of the cortex striatus was quite rough, and ac-
cording as it became dry, it appeared sprinkled over with an
immense number of small crystals, though very few were ob-
servable on the root. The formation of these crystals can be
easily accounted for ; the acid of tartar has a greater affinity
to calcareous earth, than it has to the vegetable alkali, with
which it is combined in cream of tartar ; a double elective
attraction of course takes place when a tooth is immersed
in a solution of it ; the acid of tartar combines with the lime,
and forms a salt nearly insoluble in water, and which is de-
posited in the form of crystals on the body of the tooth
whilst the other portion, the vegetable alkali, and phosphoric

* Blake. History of t Nat. Hist. Part II. page 69.