Step by Step All Ceramic Crown Preparation - T-Bone Speaks

Step by Step All Ceramic Crown Preparation

As a CEREC user we understand the importance of preparation to creating long lasting restorations.  A proper preparation makes marking the margin easier, makes design easier, and ensures enough reduction for material strength.

I wanted to take an opportunity to outline my step by step method of crown preparation.

Here is a photo of the basic burs that I use for a crown prep.  Essentially it’s 3 burs – occlusal depth reduction bur, coarse rough prep bur, and a fine diamond to finalize the prep.

Disposable crown prep burs

Disposable crown prep burs

Step 1.  Using the occlusal reduction bur cut grooves through the entire occlusal surface.  This will ensure a uniform minimum reduction.  I recommend the use of a 2.0mm depth reduction bur.

2.0mm depth cutting bur to reduce occlusal

2.0mm depth cutting bur to reduce occlusal

Step 2.  Using your thin coarse diamond go ahead and cut away the mesial and distal interproximal.  Take your time to avoid dinging the neighboring tooth.

interproximal walls removed

interproximal walls removed

Step 3.  Using the same thin coarse diamond go ahead and reduce the occlusal depth grooves.

reduce the occlusal grooves

reduce the occlusal grooves

Step 4.  Use the coarse diamond to make facial depth cuts.  This bur is 1.4mm in width and burying it a bit more than half way will ensure a 1.0mm axial reduction.  The rough prep is then completed.

facial depth cuts to ensure axial reduction

facial depth cuts to ensure axial reduction

Step 5.  Using the fine diamond go ahead and idealize your margin and smooth your preparation.  A smooth preparation leads to better milling and fit.  The fine diamond is an 856-021 which means the thickness is 2.1mm.  Using a thicker fine diamond allows me to get a 1.0mm chamfer margin.

preparation smooth and margin finalized with fine grit diamond

preparation smooth and margin finalized with fine grit diamond

An extra tip….  We utilize electric hand pieces in our office.  When finalizing our margin I go to 50% speed and I have full control over location and thickness of margin.

***  It is my preference to use disposable diamonds exclusively.  One, it ensures a sharp cutting instrument which will reduce chatter and heat generation.  Secondly, it is hygienic and clean.  Currently (as of August 2014) I am utilizing Microcopy disposable diamonds.

About the Author Tarun Agarwal

Dr. Tarun Agarwal represents the next generation of leadership for the dental profession. As a respected speaker, author and opinion leader, he is changing the way general dentists and their teams practice.

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  • Please note that my preference for non-aesthetic areas is to leave the preparation ‘high and dry’ on the buccal and lingual.

  • Josh Carpenter says:

    Hey T-bone can you please get with the 21st century and make your website mobile compatible so I can read this while I poop in the morning? Thanks!

  • Mike says:

    Hi, Is there a reason why you don’t use a 1.2 mm modified shoulder margin? Isn’t this a ceramic crown?

    • T-Bone says:

      @mike… Personally I prefer a rounded chamfer margin… Typically about .8mm

      This is thick enough for strength but yet allows a nice blending effect of the margin.

  • Reza says:

    Hi Dr. A,

    Do you have the numbers for the 3 burs you use? And do you still use disposable diamond?

    • T-Bone says:

      yes i am using disposable diamonds… we recommend either Meisinger disposables and/or Microcopy disposables…

      coarse 856-014, fine 856-020, and 556 carbide

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