![]() Hollow Ground (concave) Bevel: Hollow ground bevel allows more space for bulk of cast metal, a design feature needed in special preparations to improve material’s castability retention and better resistance to stresses. Inlay preparations include of two types of bevel Occlusal bevel Gingival bevel.A lap sliding fit is produced at the gingival margin which help in improving the fit of casting in this region.Bevel results in 30° angle at the gingival margin that is burnishable because of its angular design.Occlusal bevel or Functional cusp bevel.Types or Classification of Bevels based on the Surface they are placed on:Ĭlassification of Bevels based on the two factors – Based on the shape and tissue surface involved and Based on the surface they are placed on –īased on the shape and tissue surface involved: Over inclination of the buccal surface will destroy excessive tooth structure reducing retention.May result in over contouring and poor occlusion.It Can cause a thin area or perforation of the restoration borders.There is another type of Bevel called the Minnesota Bevel or the Reverse Bevel, this bevel as the name suggest is opposite to what the normal bevel is and it is mainly used to improve retention in any cavity preparation It is used only when capping cusps to protect and support them, opposite to an axial cavity wall, on the facial or lingual surface of the tooth, which will have a gingival inclination facially or lingually.Its use is avoided except in cases where it is impossible to use any other form of bevel. It is well reproduced by all four classes of cast alloys, internal resistance and retention features are lost in full bevel. Complete Enamel and Dentinal walls of the cavity wall or floor are included in this Bevel.Internal boxed- up resistance and retention features of the preparation are preserved with Long Bevel. Long Bevel is most frequently used bevel for the first 3 classes of Cast metals. Entire Enamel and 1/2 Dentin is included in the Bevel preparation.This bevel is used mostly with Class I alloys specially for type 1 and 2. Entire enamel wall is included in this type of Bevel without involving the Dentin.This is not used in Cast restorations except to trim unsupported enamel rods from the cavity borders. Beveling which involves less than 2/3rd of the Enamel thickness. ![]() Types or Classification of Bevels based on the shape and tissue surface involved : ![]() It is seen that in Bevels Occlusal cavosurface margin needs to be 40 degrees which seals and protects enamel margins from leakage and the Gingival Cavo surface margin should be 30 degrees to remove the unsupported enamel rods and produce a sliding fit or lap joint useful in burnishing gold. Bevels are given at various angles depending on the type of material used for restoration and the purpose the material serves.ĭefinition of Bevel: “Any abrupt incline between the 2 surfaces of a prepared tooth or between the cavity wall and the Cavo surface margins in the prepared cavity”īevels are the variations which are created during tooth preparation or cavity preparation to help in increased retention and to prevent marginal leakage. Bevels are the angulation which is made by 2 surfaces of a prepared tooth which is other than 90 degrees. ![]()
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