Narrator - Sometimes teeth are fractured to the point where a filling is not a long term solution. In that case, a cap or a crown is a much better alternative and will last much longer. And with today’s technology, the crowns are beautiful, much more life-like with a coating of porcelain that will last up to decades. Now this video will show the procedure of preparing for a crown. If you are at all squeamish about seeing a rotating drill or a little bit of blood, then this video may not be for you. But if not, let’s get started with Dr. Richard Gangwisch.
Dr. Gangwisch – Today, our patient came in with a fractured tooth. So we are going to put a crown over it so that way, we will protect the tooth for probably decades. What we are going to do first is take the enamel surface off the tooth. What we use is a diamond bur in a high speed handpiece. The diamonds are industrial grade diamonds that are bound to that cylinder. And as you can see, it takes the enamel away quite effortlessly and quite comfortably for the patient. As you can see, the patient is not flinching at all. They don’t feel a thing; just the vibration. We’ll cut through that enamel quite easily. Everyone thinks that when you do a crown, you grind it down to a tiny little peg, but, as you can tell, there is plenty of tooth there. It’s not as bad as you think. All we are doing is stripping away the enamel surface; about a millimeter and a half of tooth structure just to make room for the beautiful porcelain crown that we are going to place in there. We’ll be in real nice shape once we get to that point. Now you’ll notice that there is an area where the tooth is fractured and you are going to see it come off right now. That is why we like to put crowns over the entire surface instead of repairing the one break so that way we can protect the tooth for years to come. So we go around the tooth and gently take the enamel away. You can see that it comes off very easy for the patient. There is very little vibration so the patient is extremely comfortable. We’ll listen to some of the sounds. [Sounds] What we are going to do is place a porcelain-fused-to-metal crown on the tooth. You get the strength of the metal underneath and the beauty of the porcelain on the top which will look just like a tooth. At this point, we are going to check to see that we have enough clearance so that we have plenty of room for the beautiful porcelain chewing surface. We have a gauge to make sure that we have adequate reduction of the chewing surface. Now we go through and round all of the corners. We want to make sure that we don’t have any problems with internal stresses from sharp angles. So we have to go around and make sure that every corner is rounded. Now, there is an old base that we are taking out here. It was put in previously by a dentist years ago when the original filling was done. We want to make sure that there is no decay under there. We want to make sure all of that is out before we put the crown on. We plan on that crown being there for many years. Once we get that, we want to make sure that we get all of the corners rounded; no internal stresses at all. I’m going to put a little finish line on the edge. It’s going to go just a little bit below the gum line. That way we keep it out of harm’s way. There is less decay problems in those areas. It’s a helpful thing to put it down below the gum line there. Now we are going to have to take an impression to send off to the lab. We have some cord there that we are going to pack underneath the gums. It has a hemostatic agent. That hemostatic agent will stop bleeding. As you can tell, we have a little bit of that once we get up under the gums. So, we’ll go ahead and pack the cord around the entire periphery of the tooth. And that’s going to make it much easier for us to get a good final impression. It’s important to send labs something that is as perfect as possible so that they can do a good job on the finished product. This cord also chemically freezes the gums out of the way so that we can get a good impression around the entire periphery of the tooth. That’s where the margin of the crown is going to be, so it’s important that we get a good seal around that. To get a good seal, you have to have a good impression of that. Now we wait for a few minutes to let the cord do its work. That’s what a finished crown preparation looks like. It’s all nice and rounded. We take the cord out and there is not much in the way of bleeding. That’ll work good for a good impression. What we have is a mixing tip that mixes up a material called polyvinylsiloxane. We’ll squirt that underneath the gum and we’ll go ahead and get a real good impression of that. We have a putty in a tray that we will have the patient bite into. That putty will force that purple impression material under the gum. We’ll get a perfect reproduction of the tooth. As we close into the bite, we are now ready for setting right now. It takes a few minutes for that, so in the meantime we are going to go ahead and start making a temporary crown. What we are doing now is preparing a template. It’s just wax which was made with a mold of this tooth before we cut it down. So now we’ll get that all ready. Everything is set so we are good to go. Here’s the finished impression. This is what we are going to send to the lab. It looks great. We have good detail of all of the edges. Now, we are going to mix up an acrylic material. It’s a plastic, but it is liquid right now. In a minute or so, it will gel and then it will take a few minutes to harden. Now that it is good and hard, what we will do is peel it out of the wax impression. We are going to go ahead and trim that up. It’ll look like a tooth. Now the temporary will basically to take the place of the permanent crown while the permanent crown is being constructed. We’ll check everything; make sure that it fits good. Make sure that it flosses well. Now we have some little marks here where the bite is a little bit heavy. We have to make sure that the bite matches. So we’ll go ahead and take that out and get that adjusted. We want that temporary to be as comfortable as possible during the time that the lab is constructing the permanent crown. So, now we’ll go ahead and get some temporary cement. It’s a sedative cement that allows for some reduction of inflammation. Now what we did is placed it gently onto the tooth and the patient’s going to go ahead and bite that into place. And we let that set for a little bit. We are going to clean all of the remnants of excess cement out, making sure that this is comfortable and not irritating to the gums. The patient doesn’t feel a thing. This is very easy for the patient. The only thing that they have to do is open their mouth and we do the rest of the work. And there we go. We now have a temporary crown in place. And we’ll have a brand spanking new crown ready for her in a couple of weeks and we’ll have that video coming for you next.