1. Margin beveling for anterior teeth composites

The preparation of the enamel bevel (3), especially in the approximal-cervical region can be achieved very precisely and without trauma, using the Bevelshape file (with 40 µm granulation.

1.2 Margin beveling for composite slots

Approximal slots, as primary treatment, represent a frequent application. Because they are so short, the strain on them due to mastication is relatively small and they are thus especially suitable for plastically applied composite material. In order to optimize marginal tightness, it is necessary to bevel the approximal enamel edges (of the deeply etched pattern on the vertically cut enamel prism). Studies have shown that beveled edges prepared with the Bevelshape file (40 µm granulation) are significantly better than those obtained with conventional hand instruments.

The lateral enamel lamina (4), which remain in approximal mini-preparations, were removed when beveling was performed with the Bevelshape. In this procedure (5), the non-abrasive concave rear side of the Bevelshape file can be supported on the neighbor tooth and thus "self-stabilized".

In a cross-section of the vertical cavity wall, the small bevel (width approx. 0.4 mm) (6 and 7) corresponds to a non-prominent chamfer preparation.

ðèñ. 8

1.3 Margin beveling for inlays and onlays

In gold restorations, edges beveled with an acute angle have a smaller marginal gap, Even in tight proximal cavities following chamfer preparations, the Bevclshape file in combination with the adjustable EVA head can be used to produce a chamfer preparation. Starting in the central floor of the appro-ximal cavity, the beveling of the cervical step can be enlarged in the buccal and distal directions (8) with the inclined end of the Bevelshape file oriented distally. For beveling the approximal cavity walls, the location of the file can be set individually in the EVA instrument (9), The axial direction of the Bevelshape file should be tilted slightly in the insertion direction of the inlay.

2. Margin finishing in veneer preparations

In preparing for ceramic veneers (flat chamfer preparation), the margins must be clearly defined and smooth. Using the Bevelshape (40 µm and 25 µm granulations), the preparation border can be easily placed at the gingival border (10) and in the approximal space (11) without injury to the neighboring tooth or the gingiva.

3. Crown preparation

3.1. Margin finishing in chamfer preparation

Following piepaialion wilh a torpedo-shaped diamond, I lie dislally coated Bevelshape file (25 µm granulation) should be guided around the looth with a slight pressure towards the curvature (12). A lightly rounded shoulder is thus created. The rear of the file which has no diamond coating can be rested on the tooth stump in order to provide a solid base and sure guidance for the file.

3.2 Beveling a shoulder preparation

When the distally coated Bevelshape file (40 µm and 25 µm granulations) is utilized in this preparation, danger of injury to the marginal gingiva is distinctly less than when torpedo drills are used (13). There is also no risk of injury to the adjacent tooth surfaces even if they are very near. With rotating instruments, the risk of damage to neighboring teeth is distinctly greater. The left side of figure 14 shows a chamfer preparation which has been finished using the Bevelshape file; the right side shows beveling of a shoulder preparation.

Fig.

B40C

B25C

B15C

Beveloshape whole length on one side diamond-coated

Fig.

B40D

B25D

B15D

Beveloshape distal diamond-coated (for crown preparation)