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| Introduction: Here is a sneak peek of what our R&D department has been working on and what we believe can be done with BruxZir Solid Zirconia. While BruxZir Solid Zirconia started as a material for posterior indications, we have slowly begun to use it for select anterior cases. This case is the first time I used BruxZir Solid Zirconia as a full-arch solution on a patient that required a maxillary bridge, replacing all the teeth on just six abutments. |
Figure 1: The male patient presented with a large bridge that had fractured. All of the anterior teeth were missing. You can see it's a yellow high noble gold substructure bridge. It's a really big bridge; in fact, it's a horseshoe (full arch) bridge.
Figure 2: If you were ever going to make a case for using a base metal as a substructure, you would want to do it on a case like this, because it's going to have the highest strength as a framework. It's going to bend the least and the porcelain is going to stay on.
Figure 3: The right way to treat a case like this is to place implants where teeth are missing and then do some smaller bridges. However, the patient wasn't interested in implants. He had the bridge for 10-12 years.
Figure 4: I hadn't been doing many bridges recently. From the time we started doing BruxZir Solid Zirconia, I was looking forward to the day I would find a patient who could use a long span full-arch horseshoe-type bridge. Also, I realize that a big bridge is probably not the best way to restore this clinical situation.
Figure 5: Using the Razor bur from Axis Dental, I cut through the high noble metal, which is really easy to cut through.
Figure 6: It deflects and bends as I turn it back and forth, which makes it very easy to remove that bridge.
Figure 7: As I remove the bridge, you can see we've got some teeth, as well as some questionable posts that are in place and lack of a buildup.
Figure 8: I see the post, but there's no buildup around it; it just kind of disappears down into the canal and provides no height. I'm going in with a small Gates Glidden Drill to try to find the canal next to the post. I want to create some space because I'd like to get this post out and put a proper sized post in deeper in the canal and also attach a buildup.
Figure 9: I couldn't get in there with the Gates Glidden Drill. So, I'm going in for a second with a hand file to verify where the canal is.
Figure 10: I attempt to gauge how long this is and where the post is. I'm not actually doing endo here. The endo is still good in the apical third. I'm just trying to figure out where I can go with the post.
Figure 11: Once I determine where the canal and hole were, I go in with the Gates Glidden and develop it.
Figure 12: Next, I remove the little post.
Figure 13: It's a short, little threaded post.
Figure 14: Then, I go in and reshape the canal, mainly getting some more depth towards the apical, removing a little more gutta percha so we can put a 3M™ ESPE™ fiber post in place.
Figure 15: There you can see the post space is prepared. You can see the threads on the buccal wall of the tooth where the threaded post has been.
Figure 16: Now we've placed our fiber post in place with 3M ESPE RelyX™ Unicem.
Figure 17: You can add a little more material to the top of that.
Figure 18: And then cure it.
Figure 19: Then add a little more material on top of that and cure it.
Figure 20: These are quick cures; 2-4 second cures.
Figure 21: Once we have cured that completely, we go in to do that rough prep.
Figure 22: We want this to look like a tooth at this point. Get a long cylinder and do some occlusal reduction.
Figure 23: This is a difficult way to prep teeth. It's a lot easier to prep a virgin tooth and do the Reverse Preparation Technique.
Figure 24: We've gained a lot in buildup there; we have absolutely gained a lot.
Figure 25: Now we're cleaning some tissue off of the abutment, right in front of that anterior to the cuspid. This is the NV MicroLaser™ from Discus Dental, my new diode laser that I use on a lot more cases than you might expect.
Figure 26: As you would expect in a case such as this, where we need to expose some more clinical crown, I will touch up tissue all the time – especially in anterior cases. A lot of times, I'm trying to make tooth #8 & 9 match, which have different clinical crown lengths because of the position of the gingiva. I use the NV MicroLaser to expose more tooth but still maintain a proper biological width of 3 mm. We're going to need more tooth structure if the patient wants to go the non-implant route.
Figure 27: We're going to be putting a lot of stress on these teeth. When you take six teeth and put a whole arch on top of it in terms of a bridge, that a lot of stress to handle. Six teeth are doing the work of twelve teeth.
Figure 28: In order to have success, it's going to need to grab onto a significant clinical crown. They also need very good bony support as well. Oddly enough, as battered and broken-down as these teeth look, they do have good support.
Figure 29: We are now removing a short stubby post on the other side. You are looking at a "Brady Bunch" split screen because you've already seen how we do this and then clean it out.
Figure 30: There are six teeth left, which we will try to restore in this case.
Figure 31: These are the relined BioTemps®. The first appointment was all about controlling tissue and getting rid of old posts and staring new buildups; I had no intention of taking a final impression at the initial appointment.
Figure 32: One of the hardest things to change in the way I approach dentistry is resisting the urge to take the final impression on a day when we've made significant changes to the periodontal tissues. I have realized, however, that it is too difficult to get a good impression when you are doing all the prepping. Instead, place the BioTemps and let them heal a little bit.
Figure 33: The BioTemps have been on the patient for two weeks, and he had a chance to evaluate their size, shape and vertical dimension. Today, on the second appointment a few weeks later, we are going to take our master impression. For the most accurate impression, I use the Two-Cord Technique, where the bottom (#00 cord) goes in first and a 2E cord goes on top of it.
Figure 34: Of course, you will always see me use custom trays because I like the fit and the material savings.
Figure 35: For a case like this, a full-arch case for a roundhouse bridge, you are crazy if you don't use a custom tray. The impression is in place and the preps look good.
Figure 36: Again, this is going to be a full-contour BruxZir Solid Zirconia bridge.
Figure 37" The entire restoration is going to be solid zirconia, so it will be nice and strong. The last thing to do at this appointment is get the bite registration.
Figure 38: I've sectioned the BioTemps into three pieces. The patient bites down on the two posterior segments; with him biting together, we are able to maintain that vertical dimension for the laboratory.
Figure 39: The key to an accurate bite registration is to give the laboratory the correct vertical dimension. The two posterior BioTemps segments stay in place while we express the material onto the anterior preps.
Figure 40: The patient bites together while we wait 60 seconds at his proper vertical dimension.
Figure 41: Next, we remove the BioTemps and, with the anterior bite registration that's already set in place to get the proper vertical dimension, we squirt on the posterior preparations. The patient then bites into the anterior bite registration. Now we have a full-arch bite registration.
Figure 42: The only way to do this is to segment the temporaries so you can maintain the proper vertical dimension. This is for the cases where we're not going to open the bite or close the bite.
Figure 43: We do that when we maintain vertical dimension.
Figure 44: Our temporaries were relined. This is overkill; you don't have to do this. It's the second set of BioTemps that we're putting in.
Figure 45: The reason for a second set is, the longer we have somebody in temporaries the more likely we are to switch them out.
Figure 46: We then cement the BioTemps into place.
Figure 47: My assistant has been sternly talked to about making sure there is no temporary cement left in place. There are many ways to ensure this, with her favorite way being to floss underneath the bridge with knotted floss. She will clean out all the temporary cement and then pull the floss out.
Figure 48: Leaving temporary cement in is a big problem. We've seen cases that look good in the temporary and then we go to try-in the final work, and the problem is we've had some recession.
Figure 49: Here we are trying in the bridge.
Figure 50: There is literally no porcelain on the bridge. It is 100 percent zirconia with no porcelain. Amazing. Does it look as good as a bridge does with porcelain on it? No, and that's not something we have necessarily ever said about BruxZir Solid Zirconia, or even tried to achieve for that matter.
Figure 51: We know that BruxZir Solid Zirconia does not look as esthetic as a PFM bridge, a PFM crown or an all-ceramic crown. But the advantage is that there is no porcelain to chip off. By having the zirconia this thick, we have a super strong framework.
Figure 52: After having tried it into place, we did a couple of adjustments and it now fits.
Figure 53: We put the bridge in using conventional cement (RelyX Luting Plus). It's a resin-reinforced glass ionomer, and I have a lot of confidence in this cement, having cut off a lot of restorations just like this.
Figure 54: Unfortunately, the patient doesn't have any lower molars. Usually, we use cotton, but here I want to use something a little stronger. We have pinewood sticks in place of cotton, and ask the patient to close down as far as he can.
Figure 55: Again, the BruxZir Solid Zirconia bridge doesn't look as good as all-ceramic or PFM restorations. But for an all-zirconia bridge that has literally no porcelain on it, it looks pretty great. It can't rival the best esthetics, but maybe one day it will.
Figure 56: The reason why dentists are flocking to BruxZir Solid Zirconia is its strength. We've said from the beginning BruxZir Solid Zirconia is "more brawn than beauty." We dentists have been looking for something that is strong yet esthetically acceptable.
Figure 57: BruxZir Solid Zirconia is not going to rival IPS Empress®, but when we talk to dentists, their concern is not, "Boy, we need better looking restorations."
Figure 58: They want stronger tooth-colored restorations. In fact, I used to ask dentists: "If we came out with a cast gold that was shade A2, how many of you would use it?" and literally every hand in the room would go up.
Figure 59: Dentists love cast gold for how durable it is. It doesn't break! The fact that it's ugly and unaesthetic is why so many patients are adamant against its use.
Figure 60: This is not a cast gold in shade A2, but it's getting close. It's a step in the right direction. This is a monolithic restoration that is pure zirconia.
Figure 61: Look at that, it's pretty decent. You can tell it's not a BioTemp. Is it the greatest looking full arch bridge you've ever seen in your life? Probably not. Was the patient happy with it? Yes, definitely. In fact, there were questions about doing the lower as well, to match the upper.
