The invention pertains to a process for the fabrication of dentures for the upper jaw and/or the lower jaw, in which, with a first impression of the upper jaw and a first impression of the lower jaw, a model of each is prepared, the models are fitted together on an articulator, and an individual plate for the upper jaw and/or an individual plate for the lower jaw is prepared on the models and corrected in the oral cavity of the patient, as well as a process for the fabrication of temporary dentures for the upper jaw and/or the lower jaw and the temporary dentures themselves.
In the sense of the invention, dentures for the upper jaw and/or the lower jaw are understood to be a removable prosthesis for the fully toothless upper jaw and/or lower jaw.
In a known process for the fabrication of dentures for the upper jaw and/or lower jaw, initial impressions are made of the upper jaw and the lower jaw, these impressions are used to make plaster models, and the models are shaped in an articulator. When all of the natural teeth are missing from the upper jaw, an individual plate for the upper jaw is prepared on the model; similarly, when all of the natural teeth are missing from the lower jaw, an individual plate for the lower jaw is prepared on the model; or, when all of the natural teeth are missing from both jaws, both individual plates are prepared.
Using a high-grade impression compound, the individual plates are then fitted exactly to the upper jaw and/or the lower jaw in the mouth of the patient.
A wax wall representing the jaw line and equipped with the false teeth is then applied to the corrected individual plate.
Inside the mouth of the patient, the wax wall with the false teeth is fitted to the individual contours of the patient's mouth, wherein an adjustment to the biting plane represented by any teeth remaining in the lower jaw, or in the reverse case any teeth remaining in the upper jaw, is undertaken.
A different reference plane, e.g., the so-called Frankfurter plane, can also be selected.
Subsequently, based on the corrected plate with the adjusted wax wall and the false teeth, the casting mold for the molding of the dentures for the upper jaw or the lower jaw is prepared and the dentures are molded by casting around the false teeth with a high-grade molding compound.
The simultaneous fabrication of dentures for the upper and the lower jaws is much more complicated. The Frankfurter plane, in which the ideal biting plane is located, is then selected as the reference plane from the beginning. To this end, a physiognomy arch with a bite plate is adjusted to the patient's head; the bite plane will lie in the Frankfurter plane following adjustment. Inside the mouth of the patient, the individual plate for the upper jaw and the individual plate for the lower jaw, both prepared on the models, are also corrected using a high-grade impression compound; the corrected individual plates are provided with a wax wall and false teeth, approximately adjusted to the course of the Frankfurter plane, placed into the mouth of the patient and finally adjusted, whereupon, in keeping with the principle of spot-welding, the two wax walls are joined together at selected points by heating the wax; the unit thus formed is then removed from the patient's mouth, the two wax walls are again separated, the casting molds for the dentures are prepared, and the dentures are molded, to include casting around the false teeth positioned in the casting mold.
Even the fabrication of dentures for the upper jaw only or for the lower jaw only is not without its problems and requires precise work by the treating dentist and painstaking effort on the part of the dental laboratory involved.
With the methods known heretofore, it cannot be absolutely avoided that, following completion of the dentures and during the ensuing normal daily wear and use of same, the wearer will experience discomfort and even great pain in the chewing of solid foods (coarse bread, raw vegetables, etc.). The reason therefor is often due to anomalies of the jaws and the remaining teeth caused by long-term tooth deterioration and deformation of the oral cavity as a result of improper oral hygiene over many years, with which anomalies cannot be adequately dealt using methods heretofore practiced. Emergency resolution in the past has often involved reworking the finished dentures or, in many instances, replacing the bothersome dentures with new ones, whereby all too often only slight improvement was realized.
Such complications are particularly likely when a complete set of dentures for both the upper and the lower jaw must be fabricated for a toothless patient.
These difficulties are largely due to the fact that, in the adjusting and fitting of the individual plates, the latter are placed into the patient's mouth for only a short period of time and the patient must open and close his mouth repeatedly, while wax is carefully removed from or added to the wax walls until, based on the impression or the feeling of the patient at the moment, an optimal fit or adjustment has been presumably attained.
It is readily evident that the patient, during this adjusting and fitting work, can err in his momentary impressions and be convinced that an optimal fit has been reached, which then turns out to be in error during subsequent wearing of the finished dentures.
Furthermore, it is not possible in any of these cases to determine in advance of the fabrication of the dentures whether the future wearer of the dentures will be able to chew solid foods. It is likewise not possible to incorporate in advance assurances that the denture wearer will be able to speak without impediment and with optimal enunciation.
The fabrication methods used heretofore have, moreover, a further critical disadvantage: When dentures must be made for the upper jaw, the lower jaw, or both jaws, it is often necessary to pull any teeth remaining in either or both jaws of the patient. Until the finished dentures can be worn, however, a period of time often lasting for several weeks lapses, which period of time is primarily dependent upon the time required for the gums to heal. During this time, the patient wears a clip on the toothless jaws with blinders to mask the absence of the front teeth. During this time, however, the patient can neither speak distinctly nor eat solid food.