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.

    58/264 (page 54)
    ADAPTING THE UPPER IMPRESSION TO THE Patarat SOFT TISSUES. Figs. Nos. 34 and 35. It is important that the upper impression should be adapted to the soft tissues which overlie the posterior part of the hard palate on either side of the median line as shown in Iig. No. 35A when these tissues are relaxed. Impressions taken with the mouth open, yield models of these tissues in distended positions. When the mouth is closed, these tissues occupy very different positions, and a denture made over a model of their distended positions may fit them so poorly as to cause the nausea described on page 52. If the denture fits these tissues in the relaxed position, it will be stable at all times and will not cause nausea, no matter how long it may be. The impression is adapted to the relaxed position of these tissues by adding compound from a stick over the entire area occupied by these tissues, and while it is very soft, inserting the impression into the mouth, the lower trial plate being in place, and having the patient close the mouth and swallow two or three times. The tongue is automatically carried to the roof of the mouth during swallowing, and this action drives the softened compound into firm contact with these tissues and holds it there until it cools. It may be necessary to add compound in this way two or three times before the added compound blends smoothly with the rest of the palatal surface. ‘Trim the impression to the exact length desired in the finished plate. Then warm the posterior border of the impression again and have the patient swallow a few times. While the jaws are still closed together, the patient’s lips are parted, the upper trial plate is seized with the left thumb and forefinger in the bicuspid regions, and held firmly against the vault, the patient is caused to open the mouth and the right forefinger is passed across the heel of the plate with gentle but firm pressure and the compound is more firmly adapted against the vault and posterior to the tuberosities. The finger pressure may carry the compound to a point which will cause muscle strain. Have the patient immediately close the mouth and swallow. If the compound be not too hard, this will equalize the strain. If the compound hardens before these steps are completed, it should be warmed and the process repeated. The trial plate is now removed from the mouth and the buccal margin of each side over the tuberosities should be warmed deeply, by the aid of a small flame, without changing its form. The trial plate is now quickly replaced in the mouth. The patient is caused to close the jaws lightly in correct bite, and then to exert strong force in biting. This pressure properly “muscle trims” the posterior parts of the buccal margins to the movements of the muscles in this region. This trimming is very important and often prevents mutilation of the tissues due to congestion, or a tendency to force the plate forward in biting.