Dentistry – Apparatus – Having gauge or guide
Patent
1991-01-22
1992-06-30
O'Connor, Cary E.
Dentistry
Apparatus
Having gauge or guide
433 34, 433313, A61C 1900
Patent
active
051258331
DESCRIPTION:
BRIEF SUMMARY
The invention concerns a prosthetic positioning device designed to render portions of prosthetic impressions immobile and to produce prosthetic impressions by one-step pouring.
The technique used until now to make a dental mole consisted of filling the impression with a molding material, then turning it over onto a pile of the same material (most often plaster) or even putting the impression in a standard mold that had been pre-filled with the complementary material.
However, this practice becomes rather delicate when it must be used with a resin-based material that must be poured in liquid form, which makes it impossible to turn the impression over.
At the present time, we therefore resort mainly to a system of different shaped posts or to the technique of milling to make the two parts of the mold immobile.
The post system most often uses single or double posts. Interlocking is achieved by attaching them to the impression by pinning, putting them in position in some liquid plaster and marking the place on the impression, or by using a support plate attached to the impression, as described in French patent 2.157.331. However, these techniques do not make the immobile elements parallel; they are therefore reserved for isolated jobs or those that are not very important.
The milling technique makes it possible to mitigate the fact that the immobile elements are not parallel, which represents a major handicap in making ceramics bridges and doing other precision work. The technique consists of pouring to produce a mold whose base is flat so that milling can be done before the posts, which may be sheathed, are installed. These posts are immersed in a new mold, after the primary mold has been isolated using a layer of varnish.
The elements are then rendered immobile by sawing, as in the technique previously described. In spite of this, the milling technique has many drawbacks: broken plaster, occlusions of sheaths, etc. It involves a heavy investment and precautions that translate into a huge loss of time.
Devices are already known that make it possible to render portions of prosthetic impressions immobile by cutting them with a saw, such as those described in French patent 2.623.081 and the application for European patent EP 0.317.397.A1. These devices are in the form of plug-in or snap-on systems that make it impossible to bring the parts into close enough contact, which causes dislocations when they are unsnapped and causes scraps to fall into the mold joint, which ruins the result; also, in most cases, the impression must be poured in two steps.
A prosthetic positioning device for dentistry is already known that makes it possible to render portions of prosthetic impressions immobile and to pour them in one step, such as that described in the patent of the Federal Republic of Germany No. DE.A.3.103.637, which is characterized by the use of a snap with a spring button to interlock the two elements with an appropriate interface into which conical posts are implanted.
The metal posts sit in cavities of the same size made of the mold material; so these cavities can become receptacles for foreign bodies, which accumulate under pressure and encrust the material, which makes them very difficult to extract and makes it difficult to position the elements in relation to one another and causes wear and tear on the angles, which translates into looseness.
This invention is aimed at remedying these drawbacks. This invention, as it is characterized, solves the problem, which is to produce a prosthetic positioning device for dentistry that makes it possible to pour an impression quickly with materials that may be fluid, like resins; to obtain immobile elements strictly parallel to one another; to withdraw the prosthetic models made of wax or another soft material easily, as well as the elements on which parts made of delicate material like ceramic are mounted, which can crumble and must consequently be handled carefully with great caution; to control the presence of foreign bodies in the device and to be able to eliminate th
REFERENCES:
patent: 3153283 (1964-10-01), Weissman
patent: 3798772 (1974-03-01), Eberhard
patent: 4056585 (1977-11-01), Waltke
patent: 4240605 (1980-12-01), Waltke
patent: 4721464 (1988-01-01), Roden et al.
patent: 4801264 (1989-01-01), Weissman
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