Expert: Jeff Dalin DDS Date: 4/8/2008 Subject: Dental Crowns
Question QUESTION: I had 2 root canals completed about 3 weeks ago on teeth #4 and #5. I have have since gone for a couple of consults with different dentist to figure out which type of crown is best for me. Ideally I wanted an all porcelain crown but I heard that this might be to fragile for these teeth. I was told the best choice for these teeth would be the porcelain fused to metal...my concern with this is that I don't want to see the black line at my gum line. When I expressed this concern to the dentist, he suggested getting a porcelain fused to a "Gold" crown. He said that this would eliminate the black line & is a better crown. Of course the porcelain fuse to gold crown is more expensive, so I was wondering if it's worth the extra money. What do you recommend as the best type of crown for my 2 teeth. Also, I'm concerned about waiting too long to have the crown put on as I only have a temporary filling there now...how long is too long to wait?
ANSWER: all procelain crowns were a little brittle in the past. now we use a zirconium base and bake porcelain over that. these are considerably stronger. i do them on bicuspids and anterior teeth routinely these days. i find that patients are happier with them. is there any more risk of these cracking over a porcelain fused to gold crown? i am not sure if they are any more with the zirconium base. as far as using gold instead of other metals, it does help some. you are doing well to get multiple opinions. ask about the zirconium based porcelain crowns (procera, lava are some of the brand names). it sounds like this is the way you really want to go. good luck,
jeff dalin, dds
---------- FOLLOW-UP ----------
QUESTION: Thank you for your help. If you don't mind, I have some follow up questions. What if they don't use the zirconium based porcelain crowns, would you still recommned "all porcelain" crowns for these teeth? Also, what would make a "Gold Bonded to Porcelain" a better choice than a different metal in terms of preventing the black line. I've read that you cannot bond porcelain to a gold crown as it can withstand the heat need to do...so, this confused me. I also read about getting a metal crown with a porcelain margin to avoid the black line...what are your thoughts on this. Most importantly though is that I don't want to wait too long for fear the my temporary filling will not hold up. I had the temporary put in 3 weeks ago...how long should it hold with causing any problems? Your help is greatly apppreciated. Thank you, Linda
ANSWER: very good questions here.
they have come up with new ways to bond porcelain to all but pure gold. some names here are captek, bio2000 crowns. the gold color does not reflect the darker color from a platinum,paladium gold alloy that is normally used (actually silver colored but does look darker).
as far as timing goes, i would get moving on the crown. the temp should work fine. you just want to get the tooth protected. a root canal tooth is more brittle than a normal tooth.
lastly, make sure when they say they are doing an all ceramic crown that they really are not doing a zirconium based crown like lava or procera. some dentists will call it all ceramic or all porcelain without going into the details. tell your dentist you did some internet research and heard about these zirconium based crowns and wanted to know what he/she thought of them and if they would use it for you.
let me know if you have any other questions.
jeff dalin, dds
---------- FOLLOW-UP ----------
QUESTION: Thank you very much for your quick response. I don't understand what you were explaning about the advantage of using a gold color crown as opposed to platinum or paladium...i got lost in the explanation. How does the gold color prevent from a black line showing at the gumline. What about the crown having a porcelain margin. Also,your last paragraph was conflicting about zirconium based crowns ceramic crowns...do I want a zirconium based crown? Also, what do you think about CERIC crowns? I'm sorry to bother with all these questions, but I greatly appreciate your help!
Answer the normal metal used in porcelain fused to metal crowns is a platinum, palladium, gold alloy. it appears silver in color. when you see it in the mouth it takes on a darker gray, almost black color. these high gold content metals (captek, bio2000) appear pure gold color. if you see them, you do not see that dark grey, black color. it does not show up as much due to the color. doing a porcelain margin helps out immensely. you have to request that.
if i do an all ceramic crown, i ask for a lava or procera crown. this is a zirconium core (like a metal core) with porcelain baked over it. it is strong and it is tooth color (no black lines).
cerec is an all ceramic crown made in office by a CAD-CAM milling machine. these are not the most esthetic looking crowns and do not have a zirconium core. if you google cerec, you will find all sorts of information about them. in fact you can google lava crown and see more about the zirconium crowns.
