US 1763553 A
Description (OCR text may contain errors)
Jin-me l0, 1930. c. B. DENNIS 1,763,553
l METHOD OF AND APPARATUS FOR USE` IN TAKING.
IMPRESSIONS OF EDENTULOUS MOUTHS Filed March2l, 1929 2 Sheets-Sheet l l gwuentoz e 72 n a June 10, 1930.
C. B. DENNIS METHOD 0F AND APPARATUS FOR USE IN TAKING IMPRESSIONS 0F EDENTULOUS MOUTHS Filed March 21. 1929 2 Sheets-Sheet 2 gwuentcf Patented June 1Q, 193() UITED STATES PATENT Norifice CHARLES B. DENNIS, OF CONNEAT LAKE, PENNSYLVANIA i METHOD AND APPARATUS FOR USE IN TAKING IMPRESSIONS OF 'EDENTULOUS MOUTHS Application filed March 21, 19219. Serial No. 348,900.
This invention relates to method of and apparatus for use in taking impressions of cdentulous mouths. j
In the ordinary process of making such impressions as at present practiced, a modeling compound is placed in a tray l and While in position'in the tray is subjected to pressure to cause the modeling compound to conform to the contours of the mouth. It is then removed and the impression covered With a thin batter of plaster of Paris, after Which it is replaced in the mouth, pressure applied thereto and the plaster of Paris allowed to harden. This process is open to objection in that the heated compound compresses and displaces the thin layer of tissue or mucosa covering the maxillal. Use of the plaster layer fails to eliminate this objection and furthermore, the impression is in such close Contact to the tissue that very little space is left for the plaster, making it extremely dicult to separate and producing a rough model.
Accordingly, an important object of the present invention is to provide a method of forming such impressions wherein compression and displacement of tissue during the linal step of formation of the impression is avoided.. and wherein it is possible to construct the impression with the use of a minimuni amount of plaster, thus lessening the discomfort to the patient.
Mv method and apparatus are illustrated in the accompanying drawings, wherein Figure l is a plan view of an impression of an edentulous mouth;
Figure 2 is a section on line Q-Q of Figure l, illustrating the first step in the process of forming an impression;
Figure 3 is asimilar view showing the next sten therein;
Figure 4 is a similar view shoiviugthe third step;
Figure 5 is a sectional. view through the complete impression;
Figure 6 is a plan View of the accessory emploved in carrying out my process;
Fieure 7 is a section on line ure 6.
In accordance With my invention, I first form the compound impression in the usual manner. After formation of the compound impression C, I place thereon a filler consisting of tivo sheets of Wax 10 and ll cut to conform substantially to the modeling compound and having arranged therebetween a separating medium consisting of some thin, flexible material, such as a very fine sheet of rubber, indicated at l2. rlhis filler is heated and pressed into the compound impressionso that it substantially conforms to the shape there of. The compound impression with the filler is then placed in the p at-ients mouth and pressure applied. When removed from the mouth, a Wax impression is provided for which the compound impression acts as a tray. Y
The next step in the process is the removal of the upper Wax sheet 11 and the separat-ing medium 12, this separation being facilitated by the. use of the separating medium which prevents the sheets of the filler from adhering to each other.
Removal of the upper Wax layer or sheet leaves a space of predetermined thickness in the impression over the entire area thereof which may be filled With plaster of Paris be fore th-e impression is again placed in the mouth. Since the space provided is uniform, the thickness ofthe case provided will be uniform and a smooth, finished impression in the plaster can be obtained.
It will be obvious that by employing this method, failures in the formation of impressions may be reduced to a minimum and the Work of the dentist accordingly facili tated and decreased. The Wax sheets l() and ll with their separating media l2 may be sold as a unit in dilferent sizes and shapes as are the ordinary dental trays, j
i lhile I have above consistently referred. to the use of a compound in formino? the original or rough impression, it will, of course, be un derstood that instead of the compound, I can employ Wax or any other suitable substance having the desired `characteristics and I am still assured of having a thin uniform layer of plaster in completing the impression.
While I have above referred to the use of Wax sheet-s, it will, of course, be obvious that in the use of this term, I refer not only to y sheets of actual wax but likewise to sheets of composition material having the same or similar properties. I claim l. The method of taking impressions of edentulous mouths consisting in forming the usual composition impression, superimposing upon this impression a pair of layers o f plastic material having a medium arranged therebetween to facili-tate 'separation thereof, reforming the impression in the layers, removing the outer layer and substituting therefor a substance in a semi-liquid state which hardens as it dries and forming an im- Y pression in said substance.
2. As Van article of manufacture, a filler forv `a composition impression comprising upper and lower layers of lplastic material and a medium between the layers to prevent vthem from adhering to each other so as to'permit the removal of the upper layer after an im` pression has been made in the filler.
3. The method of taking impressions of edentulous mouths consisting in forming an approximate impression, superimposing -upon the approximate impression a plastic materlal, reforming the impression 1n said material, removing the upper portion of said material, and `substituting for :the removed `por- Y f tion of said material a. substance hardenedas it dries and forming'an impression insaid substance. l
4. The method Vof taking impressions of edentulous mouths consisting in forming van approximate impression, superimposing upon the approximate impression a pair of layers of plastic material` of uniform thickness having a mediumarranged therebetween to facilitate separation thereof, reforming the impression .in the layers, removing lthe outer layer ,and substituting therefor' a substance hardening as it dries amdforming an impression in said substance.
5. The methodxof taking impressions .of
ledentulous mouths consisting in forming :an
approximate impression, superimposing upon the approximate impressiona paar ofv layers of wax of uniform thickness having arranged therebetween a thin, flexible sheet of rubber, reforming the impression in the 1ayers, removing the louter layer, superimposing the .casting-material upon ztheimder layer and forming an impression in 4the casting material. i
6. A dental impression o f an edentulous mouth comprising'a composition base lfor-med to approximate the-impressie@ a layer of wax of uniform :thickness superimposed upon the Y composition and likewise approximating-the impression, anda ,uniform plaster .layer upon.
the wafx layer and providing the .exact pression. p.
In .testimony whereof 1I hereunto. afx my signature. v
' Y .CHARLES B. DENNIS.