Decay Under Crowns

Hey all,

Hope you had a good week. IT’S FRIDAY. I find that the weeks are just flying by. Thanksgiving is in 5 weeks. Then, next thing you know, we are planning Christmas parties and taking time off for New Year’s.

I have been really busy lately. I think the added stress of the lecture is weighing on me. I also started a 33 week Bible study where there is homework every night (I say this, but I do the homework all in one day), so between the lecture, Bible study, kids’ sports, college and pro football, I don't have much time for movies and books.

I did just buy the book Red. This is the biography of Sammy Hagar. I don't know why I want to read this book. I have always loved Van Halen. But from what I understand, the Van Halen brothers are a train wreck. I think it is the same reason we loved to watch that VH1 show, Rocumentaries. Great musicians, but all stupid idiots. Like a car accident that you have to look at as you drive. It is so amazing to me how guys can live drunk all the time and still make awesome music. They are so wasted that their managers/publicists have to go and wake them up at 4pm to get ready to go to the GRAMMYs to win Artist of the Year.

Anyway, today I wanted to talk briefly about finding decay under crowns. I do a ton of exams and I have tons of patients that have crowns. How do we reliably examine a crown to know if there is decay under there? And I am here to tell you that, after 16years of practicing dentistry, I still don't know the answer.

A patient is getting their teeth cleaned and I get called to check. I go in there, say hello, and we talk for a couple of minutes. First thing I do is look at the x-rays. I see that they have crowns.

I look very carefully at the margin of the crown on the x-ray. Now, we all know this is a crap shoot. Most of the time, the x-rays show nothing. Sometimes, the x-rays show something but it turns out to be burn-out or a root concavity. I know, for the most part, if there is decay I am going to have to find it in my intra-oral exam.

Then I go to the mouth and do an examination. At our office, the hygienists have some responsibility to help me. During their cleaning, they should get a really good idea of what is going on in the patient’s mouth. While they are cleaning the patient’s teeth, they are also feeling the interproximal margins. They need to let me know where they think an issue might be.

I start my exam and I buzz around. And when I say buzz around, I mean I have a routine. I look at each tooth, occlusal, lingual, then buccal. If I see a crown, I usually am taking my explorer and running it up and down on the margins.

I start feeling around the margins of the crown. If I go up and down, what am I looking for? We all know that if the margin is good and smooth, that doesn't necessarily mean there isn't decay. So a couple of times around the margins I will push in. Seem clean to me. But we all know that decay on the straight buccal and lingual is pretty rare. And if it is there, most of the time it is pretty obvious.

Let me take a second to ask you something. If you did find some decay on the facial, do you make it a habit to just patch it? Or do you see this as a sign that this crown is starting to fail? And if you do patch, to what extent do you patch?

Back to my exam of a crown. I take my explorer and continue up and down into the interproximal space. This is where we all know the poop is going to hit the fan on a crown. This is where you have to assume the problem is going to be. You have to be purposeful in your exam. Push at all the margins, from the buccal, then go to the lingual and push some more. Get that explorer up in there and move it around. Look for anything that is questionable.

Lately, I have been neurotic about interproximal areas. I look at a lot of crowns, and 99.9% of them are fine. So, like always, I start to let your guard down. I just look at the x-rays, fly through the exam and tell the patient how thankful I am that they are here. I tell them I appreciate them and tell them to say hi to the family. Then 4 months later, they come in with pain on the upper left.



But here is the problem: his pain was coming from #14. See, there was decay under that crown as well. For this guy, I just look at my assistant and ask, "How the !@#$%^ does this happen? Did I really miss this? I must have missed this.”

I go into denial mode. I start thinking of why this might have happened. “This guy is impossible to do an exam on. He has a tongue the size of Arizona and cheeks that come over his teeth.” But that is just an excuse. “He is getting older (I think he is close to 81) and his oral flora is definitely changing.” But again, just another excuse.

The next stage is self-doubt. I consider myself a very good dentist. I consider myself a very conscientious dentist and one that is very particular, but I definitely failed in this case.

The elusive decay under crowns. It can make a guy feel very small. Like a failure. How does this happen? I don't have any answers except you have to be at the top of your game ALL THE TIME, and everyone has to work together at your office. It isn’t easy. How is it with you?

It is supposed to be in the upper 60s at night here. Thank God summer is over. Well, it is Friday, so I won't keep you. Have a great weekend.

john