GB2095562A - Dental prosthesis bridge - Google Patents

Description

SPECIFICATION Dental prosthesis bridge, anchoring element therefor and method of producing dental prosthesis bridge The present invention relates to a dental prosthesis bridge, an anchoring elment therefor and a method of producing the dental prosthesis bridge.

It is known with patients whose teeth have been at least partially broken away, for example as a result of an accident, to connect the remaining roots by means of bridges, if necessary directly from root to root, or, where this is still possible, through a combination of such a bridge with crowns, and to build tooth prostheses thereon.

Bridges of this type are conventionally finished in dental laboratories, typically by soldering, welding, or with screws, and this can often make it necessary for there to be a number of consultations between the patient and the dentist, with the bridges being returned to the dental laboratory until the necessary precision is attained.

The present invention has as its object to provide a dental prosthesis bridge that can be built up and installed by the dentist during patient consultation, normally without the need for the assistance and facilities of dental laboratories.

To this end I provide a bridge-like prosthesis supporting or carrying element together with anchorages for its securement in the mouth of the patient.

In one embodiment the carrying elment is bent at at least one end, or is capable of being bent, so as to form an anchoring pin.

This expedient makes it possible, during a patient consultation, to measure the distance between two anchorage locations in the patient's mouth, for example between tooth root and tooth root and crown, and then to select a carrying element of suitable length, having either prefabricated bent regions forming an anchorage at one or both ends, or being bendable to form such anchorages by the dentist after he has made the measurment.

This carrying element can then be anchored on the suitably prepared roots.

In another embodiment the carrying element has a lengthwise bore at at least one end, or is formed as a small tube, so as to provide at least one anchoring opening for receiving one end of a separate anchoring pin.

In this case it is possible to employ prefabricated anchoring pins for use with prefabricated carrying elements, which can be of the same or different lengths. In this embodiment, the prefabricated anchoring pins are insertable at one end into the suitably prepared roots or crowns and at their other end are connectable to the carrying element, so that it is necessary only for the dentist in charge to select the required length of carrying element, or at the most to cut a carrying element to the exact length needed.

Preferably, the anchorages for tooth roots comprise pins and/or small tubes, the latter providing the advantage that, after the tube has been engaged in the root, the root remains accessible through the tube opening upon removal of the prosthesis carrying element.

An extremely simple form of construction of such a dental prosthesis bridge is obtained, in that the carrying element and the anchorages are connectable with one another by means of pin or screw connections, and in the case of pin connections these are preferably further secured by compressing.

Conventionally, the remaining tooth roots must be worked down almost to the level of the gums, to thereby ensure that the bridge can be supported at a certain distance from the gums. Furthermore, it is desirable that the cheming stress be taken up over a relatively large area.

This can be attained in the present invention by the use of supporting elements for the carrying elements.

These supporting elements are preferably formed as collars by means of cast metal root caps, or by means of rings laid around the ring throat into which a plastics filling material is poured. Such rings are preferably formed as tube stubs which are manually deformable so that they can be laid over the roots and can be matched to their form by finger pressure before the filling material is poured in.

The anchorages to crowns preferably comprise tube stubs, pins or bores.

The work of the doctor or dentist in charge may be substantially facilitated in that the anchoring elements for the aforesaid bridge may comprise prefabricated angle pieces that are made of wire and/or tubular material. For the anchoring of bridges at both sides of the eye-tooth region, three-legged anchoring parts may be provided of wire and/or tubular material.

The method of making a dental prosthesis bridge of the type mentioned above is distinguished in that the bridge is preferably assembled directly at the patient from prefabricated modular standard parts.

The invention will now be further described with reference to the accompanying drawings, wherein: Figure 1 is a schematic illustration of a bite region of a patient's mouth showing a bridge in accordance with a first embodiment of the invention to be fastened between two roots; Figure 2 illustrates one form of support for the bridge anchorage in this embodiment; Figure 3 illustrates a further variant of the support; Figures 4a, -b and -c illustrate three further embodiments of bridges in accordance with this invention; Figure 5 illustrates the connection of a bridge of this invention at one end to a root and at the other end to a crown; Figure 6 is a schematic illustration, analogous to that of Fig. 1, with a bridge in place that extends to both sides of the eye tooth region;; Figures 7a, -b and -c illustrate three preferred forms of supports for use between a root and the carrying element of the bridge; Figure 8 is a cross-section through a casting form ring such as can be employed for the support according to fig. 7c; Figure 9 is a schematic illustration of a prosthesis that is fixable upon the carrying element of the bridege with a slider; and Figure 10 is a schematic illustration of one means of mechanical securement between a tubular carrying element and the pin-like anchorage member.

In Fig. 1 there is schematically illustrated a bit region of a patient's mouth, which is not intended to be anatomically correct, wherein front teeth 1 are broken away and tooth roots 3 in the region of the eye teeth have been prepared by grinding them down. In the conventional manner, channels 5 have been bored into the tooth roots 3 by means of standard drills. In this embodiment there is employed as the bridge 7 a wire or small tubular piece which is here bent to a U-shape, either by the manufacturer or by the dentist, to provide anchoring regions 9 at both ends.

The bent anchoring ends 9 are inserted into the previously prepared root bores, where preferably they are secured by cement; or else preferably, and as signified by dotted lines, tubes or pins 11 are inserted into the root bores 5, to which there are then fastened the anchoring regions 9, correspondingly formed as pins or tubes.

Since the actual carrying element 1 3 of the bridge 7 must be held at a distance in relation to the gum, in order for the prosthesis to be subsequently installed, and since the loads developed in chewing upon the anchorages between the regions 9 and the roots 3 must be taken up surfacewise, in addition to the preferred spacing techniques shown in Figs.

7a -e that are still to be described, either supporting collars 1 5 can be provided on the anchoring regions 9, as illustrated in Fig. 2, or, where tubes 11 are inserted into the root bores 5, spacer collars 1 7 can be provided on the tubes, as illustrated in Fig. 3.

In Figs. 4a, -b and -c are illustrated three variants of the bridge basically analgous to Fig. 1, wherein however the anchoring regions and the actual carrying element are not formed in one piece.

According to Fig. 4a the anchorages comprise two pin-like angle pieces 19, which at one end are adapted to be inserted into the root bores 5 analogously to the illustration of Fig. 1, and at the other end are adapted to be inserted into an end of a carrying element 21 in the form of a tube.

In Fig. 4b an angle-shaped anchoring element 23 is formed at one end as a pin for insertion into the roots and at the other end as a tube stub 25 for receiving one end of a pinlike prosthesis-carrying member 27, the latter at its other end being either bent over, to directly form a further anchoring region, as in the embodiment of Fig. 1, or is connected with a second anchoring element formed analogously to the anchoring element 23.

In Fig. 4c is illustrated the possibility of a combination of the embodiments shown in Figs. 4a and 4ab, wherein one anchoring element 29, analogously to that of Fig. 4a, is pin-shaped and bent over at one end, the carrying element 31 has a bore 33 at one end for connection with anchoring element 29 and has a pin 35 at its other end for insertion into an anchoring element 37 formed similarly to the element 23 of Fig. 4b.

In Fig. 5 is schematically illustrated how a tubular carrying element 39 formed analogously to the element 21 of Fig. 4a, is anchored at one end to a crown 41 and at its other end to a root 3 by means of an angle of anchoring element 1 9 analogous to the illustration of Fig. 4a. Obviously, the connection between carrying element and root in this case can alternatively be effected by means of any other one of the variants illustrated in Figs. 1 to 4. In the illustrated embodiment, an anchoring pin 43 received in the other end of the tubular carrying element 39 is either welded or soldered securely to the crown 41, or it is secured to the crown 41 by being threaded at its free end for screwing into a threaded bore 45 provided in the crown , or, again, is pressed into a suitably dimensioned bore in the crown 41.If, however, the crown 41 and the pin 43 are welded or soldered, then this would normally have to be accomplished in a dental laboratory, whereas the use of a screw or insertion connection means that a dental laboratory merely has to prepare the appropriate bore with a standardized measurement and the pin 43 can be screwed in or pressed in by the dentist.

In Fig. 6 a bite region of a patient's mouth is schematically illustrated, analogously to Fig.

1, wherein all of the remaining teeth have been broken away up to the molar roots 3a and eye tooth roots 3b. Here, accordingly, it is necessary to provide bridges that are at an angle to one another at both sides of the eye tooth regions. To this end, a three-legged anchoring element 47 is inserted, one leg of which, as described, is inserted into the eye tooth root 3b and the other legs of which are connected with carrying elements 21 as illustrates in Fig. 4a. It will be understood that the connection between the anchoring element 47 and the carrying elements can be accom plished according to one of the variants illustrated in Figs. 1 to 4, inclusive. Preferably, these three-legged anchoring elements 47 are prepared for the dentist as prefabricated standardized parts, possibly with spacer tongues 11 as shown in Fig. 3.

In Figs. 7athrough 7cthere are illustrated three preferred variants for forming supports between prepared tooth roots 3 and the carrying elements 21 or anchoring elements.

According to Fig. 7a, there is inserted into the bore 5 of a root 3 and intermediate support piece 49 that comprises a metal cap 51 with an anchoring pin 53. The metal cap 51 surrounds a bore 54 wherein there is inserted the anchorage 19, which for example is of the kind shown in Fig. 4a. The securement between support 49 and anchorage 1 9 is accomplished, for example, by cementing or by forming the bore 54 as a threaded bore, the pin 1 9 consequently being a threaded pin, or the pin 1 9 being pressed into a correspondingly dimensioned bore 54.As a result of using the support 49, the carrying element 21 is on the one hand held at a desired spacing from the gum by the support 49 and on the other hand its stress is not transferred directly to the pin 53 but instead to the entire surface F of the prepared root.

According to Fig. 7b the support 49 comprises a small tube 55 which is inserted into the root bore 5, the opening of which extends through the cap 51. In this bore there is inserted the anchoring pin which is here illustrated by way of example as a three-legged anchorage 47, and it is securely cemented, screwed or clamped therein. This embodiment, in contrast to that of Fig. 7a. has the advantage that the root later remains accessible through the bore 57, upon removal of the bridge and the anchorage 47.

In Fig. 7c is illustrated a further variant of the support 49 which, in distinction to the variants according to Figs. 7a and 7b, usually can be produced independently of a dental laboratory. According to this embodiment, there is laid around the stump of the root a form ring 59 which can consist, for example, of thin-walled metal tubing, which can be placed around the root and matched to its form by means of the dentist's fingers. Subsequently, the interior of the form ring 59 is filled with, for example, epoxy resin, so as to provide a filling 61. To retain the advantage already explained in relation to Fig. 7b, an anchoring tube 63 can in this case be inserted into the bore 5 before the filling material is poured, the tube projecting above the cap 61 that is produced by the filling material.To ensure that the filling body 61 is securely anchored to the form ring 59, the latter is provided at its inner surface with inwardly projecting anchorages 65 which, according to Fig. 7e can be tongue-shaped or, according to Fig. 8 can be formed as interior ridges 67 on the ring 59.

In Fig. 9 there is illustrated a partially broken away prosthesis 69, to the base of which a slider 71 is fastened, so that the prosthesis can be installed on the carrying element as described.

The plug connections between tube and pins, provided on the anchorage or on the carrying element in several of the illustrated embodiments, may be secured by compressing, as is schematically illustrated in Fig. 10.

As will now be appreciated, it is usually possible for the dentist to assemble the prosthesis bridge of this invention directly in the patient without having to involve a dental laboratory. To this end, there are preferably made available prefabricated structural elements, consisting of standardized anchorages and carrying elements, which the dentist can assemble to match the dimensions required for the patient under treatment.

Claims (11)

1. A tooth prosthesis bridge, comprising a generally rod or pin-like element for carrying a tooth prosthesis, and anchorages cooperating with the ends of said carrying element for the fastening of said carrying element in the mouth of a patient.

2. Tooth prosthesis bridge according to Claim 1, wherein said prosthesis carrying element (13) is , at least at one end, bent or bendable to provide an anchorage.

3. Tooth prosthesis bridge according to Claim 1 or Claim 2, wherein the carrying element has, at least at one end, a longitudinal bore, or is formed as a tube, to provide at least one opening for receiving a separate anchoring pin.

4. Tooth prosthesis bridge according to any preceding claim, wherein the anchorages comprise prefabricated angle pieces.

5. Tooth prosthesis bridge according to any preceding claim, wherein the anchorages comprise pins and/or tubes.

6. Tooth prosthesis bridge according to any preceding claim, wherein the carrying element and anchorages are connectable by means of insertion connections and/or screw connections and with insertion connections are further preferably compressively deformable.

7. Tooth prosthesis bridge according to any preceding claim, wherein supporting elements are provided for the carrying element.

8. Tooth prosthesis bridge according to Claim 7, wherein the supporting elements are in the form of collars or of caps.

9. Tooth prosthesis bridge according to Claim 8, wherein the caps are of cast metal or comprise a ring installable around a root, preferably in the form of a tubular stub providing a mold for receiving a plastics filling material.

1 0. Tooth prosthesis bridge according to Claim 9, wherein the ring has anchors for the plastics filling material.

11. Tooth prosthesis bridge according to Claim 9 or Claim 10, wherein the ring is manually deformable.

1 2. Tooth prosthesis bridge according to any preceding claim, wherein the anchorages comprise bores or pins or tube stubs in a crown.

1 3. Anchoring element for a tooth prosthesis bridge as defined in Claim 1, characterized in that it is formed as an angle piece, of wire and/or tubular material.

1 4. Anchoring element according to Claim 13, characterized in that it is formed as a three-legged piece, of wire or tubular material.

1 5. Process for producing a tooth prosthesis bridge accordingf to Claim 1, characterized in that the bridge is assembled of prefabricated modular standardized parts, directly at the patient.