A manual of dental mechanics.

  • Coles, Oakley, 1845-1906
Date:
1873
Catalogue details

Licence: Public Domain Mark

Credit: A manual of dental mechanics. Source: Wellcome Collection.

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    which I have mentioned, there is a great lia- bility to the impression to suck, that is, the gum remains adherent to some portions of the mould, and thus gives a false model. Hinds5 composition by becoming very hard in the mouth prevents the possibility of this occurring, and in this way enables the operator to get a true mould; whereas in using wax he would, in all probability, get a false one. Hinds’ composition can be softened like wax in boiling water, and the same treatment should be adopted in manipulating it. Stent’s prepa- ration was brought out earlier than Hind’s, but it requires softening by dry heat to use it to its greatest advantage; the surface also needs coat- ing with grease of some sort when in the tray to get a clearer impression, these are ob- jections, added to which, it is wanting in plasticity. If there are many teeth standing, or a few only in isolated positions, it will require some care lest those materials that possess the property of hardening in the mouth become as troublesome to remove as plaster of Paris. Gutta percha was largely used a few years back, being thought better than wax, and plaster not having been introduced to any extent; it cannot be relied on, as it is apt to shrink, and
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