Greene brothers' clinical course in dental prosthesis : in three printed lectures; new and advance-test methods in impression, articulation, occlusion, roofless dentures, refits and renewals / by Jacob W. Greene.

Greene, Jacob W. (Jacob Wesley), 1839-1916.

Date:: [1914], ©1914

Credit: Greene brothers' clinical course in dental prosthesis : in three printed lectures; new and advance-test methods in impression, articulation, occlusion, roofless dentures, refits and renewals / by Jacob W. Greene. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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$I STILL MORE ABOUT THE JOKER. There are some cases where the lowei- teeth, for one or more reasons, can't be made long enough to provide ample space for a sufficient cut-away for such frictional tongue support, our tongue scallop. In such cases, 1 come to the rescue with a universal, ne plus ultra ''joker. This consists of a narrow, lateral addition to the lingual edge of the lower plate on both sides of the mouth—not in front. By vulcanizing (if a rubber plate) such an extension to the ])late, at right angle with its lingual walls, and then scalloping out some from both the wall and extension, a sufficient tongue* rest can be made, in almost any case, to hold down a lower denture; even if it had no other means of retention. Of course, the extension should be made and the scraping done in tlie wax; never much in the vulcanite plate. However, in swaged or cast metal plates, pro- vision should be made for the joker first in the impression, and conseqeuntli/ on the model; a stunt requiring skill, experience and persistence. ANOTHER REASON FOR THE JOKER. Another Aaluablc advantage in the joker, other than its ])roviding means for tongue force, IS that it adds area to atmospheric contact and thereby helps to give the denture more so=called suction. But beware of adding depth to the plate's edge, which was settled in the impres- sion, in the outstart. (See Index V.) It must extend laterally, and sometimes a little angling upward, to accommodate a roll of soft, moving tissue under the tongue. When the joker is properly adjusted, it sets, in normal cases, do\m onto and into the sublin-$