Conventional Bridges: Tooth Preparation course for Dental Practice

This session will look at the principles of tooth preparation including example preparations for crowns as retainers. The concepts of retention and resistance form will also be covered as well as methods of increasing retention and resistance form with auxiliary retention features.

Learning objectives

By the end of this session you will be able to:

• list the 5 key principles of tooth preparation (as described by Shillingburg 
• describe the principles of retention and resistance form with regard to tooth preparation
• explain the importance of preparation taper with regard to tooth preparations
• describe the different types of marginal finish for varying cast restorations
• describe auxiliary features that can be used to increase retention and resistance form
• apply preparation principles to the preparation of multiple bridge abutments

Full coverage crowns are the retainers of choice for bridges. Occlusal loads are higher than on single crowns and excellent retention and resistance form is needed for long term success. Occlusal load is higher on posterior teeth than anterior teeth and this is relevant to bridge design. In some low stress circumstances, in the interest of preserving tooth structure, a three-quarter gold crown or onlay restoration may be acceptable. The metal occlusal coverage would have to be aesthetically acceptable to the patient.