DE20210577U1 - screw anchor - Google Patents

Description

Description Screw anchor

The invention relates to temporary dental prostheses as immediate treatment
for gaps after extraction or implantation

In order to prevent the migration of neighboring teeth and antagonists, as well as damage to the periodontium (periodontal ligament) and to achieve a comfortable chewing situation, a temporary gap filling as quickly as possible after extraction is necessary.

A temporary restoration should be removable (for wound inspection) and inexpensive and quick to produce.

State of the art:

The following options are currently available:

• Interim prosthesis (clasp connection to the neighboring teeth):
inexpensive, relatively quick (approx. 1 day in the laboratory) production,
Disadvantage: Comfort (relatively large, with plastic plate, no stable

support and therefore mobile), aesthetics (braces), removable

Strub JR (1999), Curriculum Prosthetics Volume II, Quintessenz-Verlag, 586-572

• Adhesive prosthetics (adhesive bonds)

Strub JR (1999), Curriculum Prosthetics Volume H, Quintessenz-Verlag, 823-

852

There are two types

&ogr; Adhesive bridges -Maryland bridge:

good aesthetics, good comfort

Disadvantages: high time expenditure (several sessions), high costs,

partial grinding of the neighboring teeth, not removable, not reusable, construction must be destroyed when removed

&ogr; extracoronal adhesive attachments:

good aesthetics, good comfort, no grinding of the neighboring teeth, more stable than adhesive bridges, faster production (approx. 1-2 days in the laboratory)

Disadvantages: Costs, etching and drilling of the neighboring tooth (drill holes cause less damage than grinding with adhesive bridges), not removable, not reusable (anchors are glued in and must be destroyed when removed)

Information material from Crownless Bridge Works Germany, Daimlerstr. 4a, D-47167 Duisburg

&ogr; Immediate implantation after extraction with immediate loading:
Immediate implantation, best aesthetics and comfort,
Disadvantages: very small range of indications: only with residual bone thickness of > 1mm circular around the implant, sufficient primary stability and open healing

The subject of the invention is a temporary dental prosthesis with good aesthetics, good comfort, immediate treatment after extraction (in the same session), cost-effective and easy to manufacture, removable and stable.

According to the invention, this is achieved by using a screw connection and the screw head simultaneously functioning as an extracoronal patrix. The pre-drilling mesial and distal to the tooth gap on the neighboring teeth is made easier using a drilling aid. The screw anchor is anchored in the dentin. The outer layer of the tooth (enamel, laterally approx. 0.5-1 mm thick) is very brittle. This area is therefore drilled out somewhat larger so that the screw does not get a hold here. A soft plastic that does not stick to the screw can be used to seal this area. The prefabricated plastic matrices to match the anchors are placed on top of them and the temporary prosthesis is made directly with plastic using an impression taken before the extraction (the impression is poured with plastic and inserted into the mouth).

The invention means that only one hole is required in the neighboring tooth and the anchor can be screwed in and removed again. Furthermore, the prefabricated matrix ensures that the temporary solution snaps into place and is therefore stable during chewing, but remains removable. The small size (comparable to adhesive bonds) and stability result in increased comfort and the invisible design of the holding elements results in good aesthetics. The simple production means that immediate treatment is possible. This solution is relatively inexpensive due to the reduced work steps and the reusability of the anchors as well as the elimination of adhesives.

An advantageous embodiment of the invention is specified in claim 2. By cutting the matrix to the length of the tooth gap, the rapid design of the temporary solution and stability are improved. This is only possible with two identical anchors in the same position on the neighboring teeth.

Intended areas of application after implantation or extraction are:

• Single tooth gaps with a minimum width of approx. 4 mm possible using a drilling aid

• in the premolar area up to 2 teeth

• in the front teeth area of the lower jaw up to 4 teeth

• Combination with interims, replacing the brackets with screw anchors in the visible area

There will be two sizes. The smaller anchors will be for gaps between the front teeth and the premolar region, and the larger anchors will be for the posterior tooth region. The screw portion is 2mm or 3mm long.

The head of the screw is hexagonal on the larger screws (square on the smaller ones) which also serves as a male part. A plastic die is placed on it and clicks into place easily. The screw will have a self-tapping thread. The diameter of the screw is approximately 0.5-1 mm.

The components:

There must be two types of matrix for each anchor (small and large), so that depending on the position of the screw anchor after screwing in, the matrixes on both sides of the gap are roughly parallel to each other. The temporary restoration can be modelled directly on these plastic matrixes using a self-polymerising material. Two small clips on the edge of the plastic matrixes will snap them into place and provide a secure hold when speaking and chewing.

Additional part:

• Drill, with a stop at 2 or 3 mm and a corresponding increase in diameter to the last 0.5 mm - 0.8 mm - for more intensive preparation in the enamel

• Drilling aid:

Since it will be difficult to insert the angle piece into smaller gaps at the appropriate angle, a drilling aid is necessary. This is placed on the angle piece. It is approx. 1-1.5 mm wide and approx. 1.5-2 cm long. The force is transferred to the drill in the gap via gears or V-belts. It can be sterilized and reused.

Examples of implementation based on figures 1-7:

Fig. 1: Variant 1 of the matrix for the large screw anchor

Fig. 2: Variant 2 of the matrix for the large screw anchor

Fig. 3: large screw anchor with hexagon head as male part

Fig.4: small screw anchor with square head as male part

Fig.5: Variant 1 of the matrix for the small screw anchor

Fig.6: Variant 2 of the matrix for the small screw anchor

The screw is screwed in until the surface or edge is at the top, so that an insertion direction of the provisional prosthesis is achieved via variant 1 or 2.

Fig.7: Drilling aid:

The angle piece is connected via the drive shaft 1. The power is transmitted in parallel via a V-belt or gears approx. 1-1.5 cm. The drill can be inserted into 2. To keep the construction steady, an extension of at least 5 cm is attached to 3.

Claims (3)

1. Screw anchor consisting of a screw with a hexagon or square head that can be screwed into the tooth and a matching matrix for creating dental prostheses, characterized in that the hexagon or square head of the screw can accommodate the matrix and the screw is approx. 2-4 mm long. 2. Screw anchor according to claim 1, the matrix of which is supplied in longer pieces and is cut to the length of the tooth gap. 3. for inserting the screw anchor according to claim 1, drilling aid for drilling holes in the tooth wall characterized by:
the size of approx. 1-2 mm wide and a parallel transmission of the direction of rotation of the angle piece.