How to Remove a Front Tooth Crown to Determine the Depth of A Fracture

This patient had a loose front crown that had been incorrectly banging against the lower teeth for years. We needed to determine the extent of the fracture within this tooth to determine whether it could be saved or need extraction and then placement of a dental implant.  This video on how to treat a Crack Under Front Tooth Crown was performed in our NYC Cosmetic Dentistry office.

Hi it’s Dr. Jeff Dorfman at the Center for Special Dentistry in New York City looking at two very mobile front teeth, and you can notice that when the patient has these very worn teeth here and when she closes (bite down, open and bite a few times), you’ll see that these front teeth actually move because when these porcelain crowns were made they were made and hit too much on the back. So what I’m going to do right now is I’m going to slowly take this apart and see where the fracture is in this tooth and see whether this tooth can be saved or not. And I’ll also be adjusting these bottom teeth to reduce the vibration on the upper front teeth which dentists call “fremitus.” And actually what I’m going to do here is I’m going to take a photograph of the bottom front, extra-oral first, I want to photo-document the extent of this. Good, I’m going to adjust this first to eliminate the fremitus, and you can see all the wear on these lower front teeth. Okay that’s really the first thing we need to do. (This will not hurt. You’re okay there, I know. Close.) Okay, you can still see there is substantial vibration of that front tooth—that’s how the crown was made, and it’s wrong. (Close. Open.) Okay, the vibration is now dramatically less; it’s still here though. I’m taking a polishing stone on here right now. Okay camera please, extra-oral. Now we’re going to look at where this break is on the top and how far deep it goes. I’m going to drill off the porcelain. You can see I still have not gotten to the tooth underneath yet. Still haven’t gotten to the tooth yet. You can see that this tooth prep was very, very short. I’m looking to discover the base of the crack in this tooth, and I want to get the porcelain veneer off first. My feeling is that the tooth may be cracked deeper below the gum and that the tooth may not be restorable or fixable, but I want to discover that before making that decision. You can see there is very little tooth here. If you look at where we are so far—let me get an extra-oral picture—you can see there is very little tooth under this crown. A very little amount. There is still porcelain to be removed. I’m going to do intra-oral also please. You can still see there’s porcelain on the occlusal of the prep. Okay, so let’s see a little bit better now. With this finger touching the gum, I don’t feel movement higher up, which is good, but I still see movement here, and I need to see where that fracture is. If I actually take the intra-oral camera, I can photograph it from the palatal side again. (Open a little.) You can clearly see it, right? So the question is where is it, how far does it go below the gum? (Suctions again, both please.) Good, that what we wanted. That’s where we want to be. Let’s get a video shot seeing exactly where we are, and seeing where the movement is. The movement appease to be superficial, which is great news so far! Cautiously great. Let’s see where the cracks are. And get the video camera right in here, come up close, to see if you can see it. And I’m going to see there’s a crack here and there’s a crack here. There’s a crack here and there’s a crack here. And I’m going to wiggle this slightly so you’ll be able to see the discontinuity. Look at that, isn’t that wonderful? That could be—let me take a camera picture of this—if that holds then this is great news. Now were you able to see the wiggle? I’ll just do this one more time and then we’ll see if this can be adjusted. Just focus from this angle if you can. I’ll move the light out of the way so you can see it better. But watch, right around here, see where the wiggle is. That’s wonderful! Let me get the intra-oral camera again. Pick up your chin slightly, because I want to get a picture. It appears that the fracture does not go deep. Alright so let’s just get the video on this. And let me do this. So far that is good news for us. Good news. I think it’s failure of the post. And look! Post is out. Good! That’s great news! So let me get a picture of this, I’m going to put this here. That is really good news. I’m going to take a picture of that. One more. Good, I’ll take another picture here. Let me get a palatal view. I’ll get directly inside. Let me blow air and then we’ll get an extra-oral view. Looks like there is a crack on the mesial side of the tooth—you can kind of see it there on the top, but that is not a deal killer. Even though we have a little bit of a crack on the mesial, I still think the tooth is restorable, which is good news. We’re just going to stop the video, we’re going to get an x-ray to see where we are, but I think that’s pretty good news. So anyway, what we just did, is showed how to disassemble a tooth to discover the extent of a fracture, to determine if the tooth is restorable, meaning savable, or if it needs extraction. My feeling right now, pending an x-ray, is that this tooth might still be restorable and savable. The patient will be happy! We’ll take an x-ray, and if so then we’ll proceed with restoring this tooth. This is Dr. Jeff Dorfman at the Center for Special Dentistry in New York City.