ProCeram™ PFMs

One of the most common and more productive procedures performed in a GPs office is crown & bridge, the majority of which is still PFM restorations. ProCeram is our proven industry standard PFM. It can be fused to non-precious, noble or white high-noble alloys. It is our most prescribed PFM for routine crown & bridge casework. ProCeram Case Treatment Plan: Bridges on teeth #4-6 and teeth #12-15; crowns on teeth #7-11; a buildup on tooth #9; and BioTemps Provisionals.

As you look at tooth #9 and #10, notice that we have metal margins showing from the previous PFMs due to gingival recession. Additionally, there is dark root structure on tooth #9, as this tooth has been antidotically treated.

We begin by preparing the anterior teeth. We remove the old PFM restorations, using a diamond for the ceramic and a carbide for the metal.

The crown remover spreads the crowns so that we can easily remove its pieces from the mouth.

We notice that the central incisor is short compared to the lateral.

Because the central incisor is short, we buildup that tooth and cure it into place.

Then we begin prepping the built-up central incisor.

We use a diamond round bur (at high-speed) first to prep the gingival margin. We do this because we still have our tooth landmarks at this point. This is a self-limiting depth cut; this bur will only go as deep as the shank touching the outside of the tooth will allow.

So, what we are doing now is going to look like a smile. We're not going to touch the gingiva, we're going to keep it right at the margin of the gingiva and take it right along the facial until we hit the adjacent tooth interproximally.

We have placed our 2 mm incisal edge depth cuts. Now we'll connect those.

We place our facial depth cuts of 1.5 mm and accomplish that reduction as well.

Now we do our lingual reduction with a football bur.

Then, using the 3M ESPE Sof-Lex disc, we remove any sharp edges from the preparation, especially at the incisal angle.

BioTemps have the reline material inside, and we'll wait for that to get into its doughy stage.

As the BioTemps reline material continues to set, we use a micro-brush to remove excess material from the margins.

We are now finished preparing the anterior teeth. We've relined the BioTemps and placed them on the teeth. Now we will prepare the bridge on the left-hand side of the mouth. This bridge will include tooth #11 and #12 as the anterior abutments. Tooth #13 and #14 will be pontics on the bridge, and the distal abutment for the bridge will be tooth #15.

As with the anterior teeth, we'll begin by breaking the contacts between the teeth.

We're ready to place our gingival third depth cut. This is a very important depth cut. As we look at the models and the impressions that come into the laboratory, this is definitely one area, in addition to occlusal reduction, where dentists have a tendency to under-reduce the preparations.

Another way to place depth cuts is to use a barrel diamond, which is often used in veneer preparations. We'll go ahead and use this, just as an example, on the facial surfaces of the anterior teeth for our axial reduction. Then, we'll use a tapered diamond to connect the depth cuts and ensure we have adequate reduction for the lab technicians.

We have finished our tooth reduction. At this point, we're going to check the occlusal reduction on the tooth. This is Capture Hard Bite, which is sold through Glidewell Direct.

After about 45 to 60 seconds, we'll have the patient open and we'll use some calipers to measure this. We have 1.8 mm of reduction.

This is the STS Diamond set from Brasseler; it stands for shorter-than-short, and they've got very short shanks and short cutting tips as well. This diamond set is perfect for areas where a patient just doesn't have the space to fit a regular-sized diamond.

As per the Two-Cord Impression Technique, we place this first cord. This is an Ultradent 00 cord, and we'll just tease it under the gum tissue. Watch how on the mesial aspect of the preparation you can really see the margin come into view as the gingiva is retracted.

I really like this technique because it allows me to visualize the detail at the margin. So, this first cord will be packed into place and then I will take a red fine diamond and finish the gingival margin.

This is some final finishing of the gingival margin with our fine-grit diamond. You can see the first cord is in place at this point and has retracted the tissue, so we have a clear view of our gingival margin. It's also protecting the tissue. We still do not want to touch the gingiva with this bur at any point.

This is the placement of the second cord, the top cord. This is an Ultradent #1 cord. We tease this under the tissue, where it will remain in place for about seven to 10 minutes, at which time it will be removed and the impression will be taken.

We are painting the captured adhesive on this custom tray, even though it's already perforated just for a little additional hold. I like to use custom trays, whenever we have more than two or three preparations because I know the tray is going to fit perfectly and we end up using less impression material as well.

We are now ready to take the impression. We have re-wet the top cord before we remove it so it doesn't cause any bleeding, if it's happened to it here, to the gingival tissues.

Once the cord is removed, my assistant dries the preparations and syringes the wash material around the preparations. We then insert the custom tray filled with the tray material.

Because we used the Capture Bridge set material, best indicated for multiple preparations, we have a three minute intraoral set time. We are now going to remove the impression, and I will take a quick glance at it here to make sure everything looks good. And it does.

Over the years, one of the common problems I've noticed with these large anterior cases is they'll come back from the laboratory with a canted smile at times, where the incisal edges or the smile line is slanting either to the left or the right.

What we do to make sure this doesn't happen is give a vertical and horizontal stick bite to the laboratory.

So, we'll put some bite registration material on the teeth, then we'll place a horizontal stick line. We'll view the patient with their eyes open, and put the stick parallel to the inter pupil area line.

Then we'll go ahead and place some more bite registration and put a stick right at the patient's midline, right underneath their nose, to give the information about the midline and the horizontal plane to the technician.

Here we are using an occlusal photographic mirror to check the draw on our preparations. I find this works better than a smaller mouth mirror to be able to line up multiple preparations. I know it's a little difficult to see the molar prep, but I can see that it does draw well with the first bicuspid on that side and the two bridge abutments on the other side draw as well.

At the first appointment, we prepared the four anterior teeth.

At the second appointment, we prepared the posterior teeth and the bridges.

So, we have made one single BioTemps unit for all these preparations now and it has been realigned. I will now remove that.

We're going to clean the provisional cement with a Preppies pumice.

We have tried in the restorations and now we're ready to cement them. We place a desensitizer on the teeth; this is Hemaseal and Cide from Advantage Dental Products.

We're now ready to place the final restorations with 3M ESPE RelyX Luting Cement. We're going to start in the anterior, place the central incisors, move onto the lateral incisors. I like to just start in the front so we can start our cleanup in the front as well. That way, if we do have any contact issues that need to be addressed during cementation, we can take care of those in the posterior so that we don't have to change the mesio-distal widths of our anterior teeth.

This case has been cemented, and we'll give the patient two weeks to wear the case, to function with it. At the end of the two weeks, he reports no problems. The inclusion's good, his function's good, his phonetics are good.

Here is an occlusal view of the cemented porcelain-to-metal restorations. You see we got nice arch form. Often times, I'll use this view to site down and look and make sure we have nice facial anatomy. And I can see three distinct globes, for example, on the central incisors. That looks fantastic; the lingual embrasures look good, the facial embrasures look good. I am very pleased with how the crowns look from this view.