Dr. Nammy Patel, founder of Green Dentistry in San Francisco, California, discusses biocompatible crowns. She is also the author of the best selling book, Age With Style: Guide To A Youthful Smile and Healthy Living.

John Maher: Hi, I’m John Maher. I’m here today with Dr. Nammy Patel, founder of Green Dentistry in San Francisco, California, helping patients recognize the vital connection between dental health and whole body health, and author of the bestselling book, Age With Style: Guide To A Youthful Smile and Healthy Living. Today, our topic is biocompatible crowns. Welcome, Dr. Nammy.

Dr. Nammy Patel: Hi, John. Thank you for having me.

What Does Biocompatible Mean?

John: Sure. So, first of all, what do we mean by biocompatible?

Dr. Nammy: Biocompatible means that they do not have reaction with the body. So, compatibility means that it works well, and bio means biologically sound. So, it basically means that it doesn’t cause any toxic reactions or it doesn’t have any toxic effects in the rest of the body.

John: Okay. And what characteristics specifically does a crown have to have?

Dr. Nammy: Well, the first we always want is that it’s a good fit because if a crown doesn’t have a good fit, it’s not going to last. The second is that it works properly, meaning that the bite is right because, again, if the bite is not right, the crown’s going to break and it’s going to have problems. The next thing that’s really important about crowns is that they look good. We want something that is going to make us happy when we look at it. So, the color is right, the shape is right. If it’s too big and fat, it can cause gum disease. And if it’s too skinny, it can cause gum disease as well and bone loss. So, it’s really important that the crown is done in harmony with the rest of the teeth, and then they’ll… And also, make sure that it looks proper because there is a way that teeth are supposed to look, and specific teeth look differently, like your front teeth look different than your back teeth. And then the last one is that it’s strong enough. Strength is really important because we want to be able to withstand the forces of clenching, grinding, and chewing and have something that’s going to be long lasting.

John: And I believe that we’ve talked about this before where you actually don’t want the crown to be stronger than your other teeth as well because that can cause problems.

Dr. Nammy: Yes, it can. And there are different types of materials that are in crowns, and so the ones that typically cause that breakdown are metal or if there is metal fused to porcelain. And then there’s some porcelains as well that actually wear the natural teeth down if there’s a crown made out of it.

John: Right. So, again, it goes back to that fit. You don’t want to have a crown that’s super strong, stronger than your other teeth, and then maybe as touching those other teeth where it’s able to grind them down and that sort of thing.

Dr. Nammy: Yeah.

Typical Crowns vs. Biocompatible Crowns

John: Yeah. So, what materials were used in typical crowns, and what kinds of issues did those materials cause?

Dr. Nammy: So, the most common one that is used for typical crowns is metal fused to porcelain, and the reason why they did that is because they thought, “Oh, having a metal substructure is going to make this crown so strong that it’s going to last forever.” And the problem with that is that the metal actually causes an oxide reaction. So, what the metal does is the metal actually irritates the gum tissue and it starts creating this black line around the gums and it harbors bacteria, and then you get more cavities around them and you lose gum tissue. So, it starts having a huge problem down the road. And typically, the life cycle is about five years. Then there’s all porcelain crowns and there are porcelain crowns are made in the lab, which are layered. And in between the layers tend to be air bubbles that can chip and crack. And then the material that I really like is a biocompatible ceramics, and I love those because they actually last a really long time and they’re pressed together tightly so you have a really dense, strong natural tooth-like material.

John: Okay. And go into a little bit more detail on what the benefits of those biocompatible ceramics are for crowns.

Dr. Nammy: So, the biocompatible ceramics actually resist bacteria and they actually are the strength of your natural tooth structure, which is really great because then they don’t break as often. And they also don’t cause any of that oxide reaction that we were talking about earlier with some of the older crowns, and the beauty is that they look so natural and so lifelike and they last such a long time and that it’s really wonderful to have materials that can almost replace natural tooth structure.

John: So, they do last a long time. Will I eventually have to come back and get those replaced or will they just last me forever?

Dr. Nammy: To be honest, John, what we find is that my biocompatible crowns are just fine. The cavities that occur are actually on natural tooth structure. So, as far as the actual crown itself, it lasts a lifetime. Where the cavities or where the actual problem occurs is actually on the natural tooth portion of it, and that’s where I tend to find a majority of the reason why we have to redo the crown is because the cavity’s actually underneath the crown or underneath into the natural tooth structure.

John: Right. So, you have a part of your tooth. Your natural tooth is there. And then the crown, as the name sort of indicates is on top of that natural tooth. So, you can still have some problems with the underlying sort of tooth that you might have to take off the crown in order to get to. Is that right?

Dr. Nammy: Mm-hmm. Yep.

John: Okay. Well, that’s really great information, Dr. Nammy. Thanks for speaking with me today.

Dr. Nammy: My pleasure.

John: And for more information about Green Dentistry, visit the website at sfgreendentist.com or call (415) 578-9347.