Types of Bevels and their Uses in Tooth or Cavity Preperation

What is a Bevel ?

Bevels are the anglulation which is made by 2 surfaces of a prepared tooth which is other than 90 degrees. Bevels are given at various angles depending on the type of material used for restoration and the purpose the material serves.

Definition of Bevel: “Any abrupt incline between the 2 surfaces of a prepared tooth or between the cavity wall and the cavosurface margins in the prepared cavity”

Bevels are the variations which are created during tooth preparation or cavity preparation to help in increased retention and to prevent marginal leakage. 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.

Types of Bevels and their uses in tooth or cavity preperation

Types or Classification of Bevels based on the shape and tissue surface involved :

Partial or Ultra Short Bevel:

  • Beveling which involves less than 2/3rd of the Enamel thickness. This is not used in Cast restorations except to trim unsupported enamel rods from the cavity borders.

Short Bevel:

  • Entire enamel wall is included in this type of Bevel without involving the Dentin. This bevel is used mostly with Class I alloys specially for type 1 and 2.

Long Bevel:

  • Entire Enamel and 1/2 Dentin is included in the Bevel preperation. Long Bevel is most frequently used bevel for the first 3 classes of Cast metals. Internal boxed- up resistance and retention features of the preparation are preserved with Long Bevel.

Full Bevel:

  • Complete Enamel and Dentinal walls of the cavity wall or floor are included in this Bevel. It is well reproduced by all four classes of cast alloys, internal resistance and retention features are lost in full bevel. Its use is avoided except in cases where it is impossible to use any other form of bevel .

Counter Bevel:

  • 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.

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 preperation

If we do not use functional Cusp Bevel –

  1. It Can cause a thin area or perforation of the restoration borders
  2. May result in over contouring and poor occlusion
  3. Over inclination of the buccal surface will destroy excessive tooth structure reducing retention

Types or Classification of Bevels based on the Surface they are placed on:

Functions of Gingival bevel:

  1. Removal of Unsupported Enamel Rods.
  2. Bevel results in 30° angle at the gingival margin that is burnishable because of its angular design.
  3. A lap sliding fit is produced at the gingival margin which help in improving the fit of casting in this region.
  4. Inlay preparations include of two types of bevel Occlusal bevel Gingival bevel

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. These bevels are ideal for class IV and V cast materials. This is actually an exaggerated chamfer or a concave bevelled shoulder which involves teeth greater than chamfer and less than a bevelled shoulder. The buccal slopes of the lingual cusps and the lingual slope of the buccal cusps should be hollow ground to a depth of at least lmm.

Functions of Occlusal Bevel:

  1. Bevels satisfy the requirements for ideal cavity walls.
  2. They are the flexible extensions of a cavity preparation , allowing the inclusion of surface defects , supplementary grooves , or other areas on the tooth surface.
  3. Bevels require minimum tooth involvement and do not sacrifice the resistance and retention for the restoration
  4. Bevels create obtuse-angled marginal tooth structure, which is bulkiest and the strongest configuration of any marginal tooth anatomy, and produce an acute angled marginal cast alloy substance which allows smooth burnishing for alloy.

Functional cusp Bevel:
An integral part of occlusal reduction is the functional cusp bevel. A wide bevel placed on the functional cusp provides space for an adequate bulk of metal in an area of heavy occlusal contact.

Latest Comments
  1. narmin

    thanx alot :)

  2. Rose and sharon

    Truly helpful!

  3. Will Baisley

    Polyneuropathy is a pattern of nerve damage which is quite different from mononeuropathy, often more serious and affecting more areas of the body. The term “peripheral neuropathy” is sometimes used loosely to refer to polyneuropathy.

  4. abiraj

    thanks alooooot sir

  5. a rahman a raouf

    is there any pics for counter bevel ??

  6. praveen john

    add something about scalloping bevel

  7. TEJASWINI

    THANK U FOR THE INFO SIR BUT I AM SEARCHING FOR REVERSE BEVEL,IT WILL BE FINE IF ADD A BIT ABOUT REVERSE BEVEL

  8. Varun

    Have updated the post with Reverse Bevel, there is not much info available about it, what I know is that it is used for retention and is also called as Minnesota bevel. Will try to gather more info and update it in the post.

  9. Ali

    Do we give bevel on enamel for a composite restoration?

  10. esha

    What’s the difference between chamfer and bevel?

  11. Varun

    It is useful to give a bevel for composite restorations as well because bevel will remove any unsupported dentin on the tooth surface which can lead to marginal leakage later on.

  12. Nida

    Is there any contraindications for bevel

  13. Varun

    Bevel is contraindicated on the Cavosurface margins of a Class I amalgam restoration as it will lead to fracture as a thin layer of amalgam is brittle and will fracture easily leading to marginal Leakage in future and it is also difficult to polish.

  14. M.bilal anwar

    How can i download it?

  15. Dija

    Do we give bevel in class 2 amalgam restoration?

  16. Varun

    Yes, it is important to give a bevel.

  17. Dija

    At which site we will give bevel in class 2 amalgam restoration?

  18. Syed

    Which instrument is used for gingival margin bevel?

  19. Varun

    For Gingival Margin bevel, we use “Enamel Hatchet

  20. Muhamed Aboelela

    Which one is the most important bevel in inlays please, is it the gingival or the occlusal Bevel ?!

  21. Varun

    There is nothing as most important, both the bevels serve their purpose in the success of a Restoration so both the bevels are required depending on the cavity and the inlay being prepared.
    If the Gingival bevel is not done properly there can be marginal leakage at the gingival level and if the occlusal bevel is not given properly there can be fracture of the restoration leading again to marginal leakage and failure of the restoration.

  22. Muhamed Aboelela

    I came through a question of HAAD exam that says which bevel is the most important in inlay restoration , so am guessing both are important idk how but i think there are two answers that are right .. so thank you so much

  23. Muhamed Aboelela

    am sorry doctor but i would be so thankful if you could help me with some answers , i mean if it won’t disturb you ofcours .. thank you again

Leave a Reply

Your email address will not be published. Required fields are marked *