Prosthetic articulation / by George Wood Clapp.

  • Clapp, George Wood, 1870-
Date:
[1914], ©1914
Catalogue details

Licence: Public Domain Mark

Credit: Prosthetic articulation / by George Wood Clapp. Source: Wellcome Collection.

    36/264 (page 32)
    Figure No. 17. When the compound was pressed up under the lip and cheeks as shown in Figure 13, it was carried higher than the margin of the im- pression will be, in order that it might be trimmed by the action of the muscles. The motions of the cheeks and lip shown in Figure 17 trimmed the margins of the compound, by turning it outward and downward where it interfered with their movements. In doing this, they fre- quently turn it too far downward, and it is necessary to press it inward against the tissues and carry it again a little upward. These ends can be achieved by applying the thumb and forefinger of the left hand to the cheeks and lip, below the upper margin of the tray, and giving them a slight rotary motion, with gentle inward pres- sure. Care must be taken not to pull downward. The tray 1s mean- time held firmly in position by the finger of the right hand in the vault. This massage will also continue the downward movement of the excess compound and turn it beneath the tray. When this massage has been completed, an impression should be sufficiently well adapted to the vault of the mouth and the surface of the ridges so that it will not rock. If it rocks, it must be corrected or remade, since the rocking will invariably lead to trouble. A second method of securing satisfactory impressions of very soft anterior ridges is to cut away the anterior border of the upper baseplate impression as far on either side of the median line as the soft tissue ex- tends and back into the tray as far as the lowest part of the soft tissue. Take the bite with the front cut out. When the bite is complete, thoroughly warm the compound in contact with the soft tissue, over a small flame. Place a new border of compound to approximate the border cut away. Quickly place tray in mouth and have patient close and make lip and cheek movements. Place the inner side of the index finger on the outside of the lip, along the upper margin of the new border and make a gentle but firm pressure inward and downward. This forces the soft tissue backward and conforms the compound to it. As a general thing, an impression which has been carefully taken, this far, will have also enough of what Dr. Greene calls “sticktion’’ to permit its use in the later stages of impression taking.