Ellis Classification and Class 4 Composite Prep

Study Notes

Ellis Classification of Fractures

Ellis Class I: Fracture remains confined to enamel.
Ellis Class II: Fracture extends into dentin.
Ellis Class III: Fracture reaches pulp causing pain; typically requires endodontic therapy, such as root canal treatment.

Class 4 Composite Preparation for Teeth #8 or #9

The preparation shape should correspond to the extent of the fracture.
Internal retention should be established in the dentin area.
Continuous bevel marginally at the external cavosurface margin (facial, lingual, incisal, and gingival).
The outline form for Class 4 preparation involves a diagonal fracture covering at least half of the facial width at the incisal edge.
Adhere to the original fracture or decay geometry; do not extend preparation beyond fracture.

Creating the Fracture for Class 4 Composite Preparation

The fracture zone is prepared by removing the discolored area using a tapered diamond bur.
Ensure the gingival part of the fracture aligns just below the proximal contact.

Internal Preparation in Dentin for Class 4

Internal preparation should be confined to dentin for enhanced restoration retention.
Use a #330 pear-shape carbide bur or a #33 1/2 bur, removing dentin to a depth of 1 mm.
Depth measurement can be done with a perioprobe for accuracy.

Beveling Techniques for Class 4 Preparation

Begin beveling on the external facial surface using a tapered diamond bur; avoid extending bevel to internal prep.
Bevel width should be 2 mm on the facial part of preparation; do not attempt gingival margin beveling at this stage.
Continue the bevel on the lingual surface with a width of 1 mm and include the incisal angles.

Beveling the Gingival Margin

Protect adjacent teeth using a steel matrix and wedge before beveling the gingival margin.
Carefully extend the bevel onto the gingival margin after ensuring proper protection.

Class 4 Composite Restoration

Complete the final prep before bonding the restoration; ensure all previous steps are followed meticulously for optimal results.
Post-beveling and internal prep adjustments, finalize the restoration technique in accordance with the established guidelines.

Description

This quiz focuses on the Ellis classification of tooth fractures and the principles of Class 4 composite preparation for teeth #8 or #9. You'll learn about the different classes of fractures and the specific techniques required for effective composite restoration. Test your knowledge on fracture management and dental preparation methods.