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]

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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$TWO WAYS TO FIT TRAY. For this we have two methods: the student's method and the practitioner's method. I '11 first give you the student's way. It is to first take a common, hurried impression any old way, and make a hurried model from it; and then fit a tray to this a]j]jroximate model, in- stead of fitting it to the mouth itself; the lat- ter being the practitioner's method. The student's method is, in fact, a good one for even the most experienced, who are willing to take a little extra time, say five minutes, to first get this approximate plaster model. Indeed, it is the preferable way, and becomes the settled one with many of my students in practice. Well, I have a model here before me. We '11 suppose it to have been made by some one of you from a hurried common imi^ression—^^or, as for that, from a good impression (good, but untested and not knozcn to be good). AVe '11 take an old, soft=metal tray and cut it off at the heel so as to be a little shorter than we think our coming plate should be. judging from the model; and then we '11 trim it down at the sides and in front, so as not to be quite as high as we think our plate should be. AVe '11 thus make it seemingly about a full one-eighth of an inch too short and too shallow all around. And we '11 fiatten it down so as to have very little elevation in the center. If we get its rim an eighth of an inch really too low. no harm done; for our impression material will become a rim of itself. Then ^\e want the metal tray a little larger than oiu- model (or mouth), so as to work loose- ly over it; say with a scant eighth of an inch play all around it.$