Tag Archives: damaged CEREC crown

My crown keeps falling off

I had a CEREC crown placed. However, it has come out several times within the last year. Finally, after the fourth time, I consulted a different dentist, who replaced the crown with a zirconia porcelain crown, but it, too, has come out several times. The dentist suggested a full porcelain crown, stating that the cement is adhering to my tooth, but not the crown. He indicated that the all-porcelain crown is rough of the underneath and would, therefore, bond to the cement more effectively. I’m unsure of what my next step should be, but I am tired of the trouble these crowns have caused. What do you suggest I do?

Thank you,
Kodi

Kodi,

The CEREC crown, or same-day crown, is created by a computer in the dental office, the day of your appointment. When prepared and adhesed correctly, the crown will remain permanently affixed to the tooth. The material of which your crown is made is not indicative of how permanent the bond will be. Whether your crown is porcelain, gold, CEREC, or zirconia, all are made to stay permanently.

However, there are two factors that can determine if a crown will stay on permanently or not. They are the bonding strength of the cement, and the shape of the prepared tooth. The most important of these is the shape. If the tooth is prepared with little taper, a crown can be adhered with a weak cement, and it will stay permanently affixed. However, if there is a lot of taper, even some of the strongest cements will have difficulty staying on.

This is not implying that getting a solid bond between the crown and tooth would not solve your problem. The cement’s strength is important. But, when a tooth is prepared with good retention form, the crown will not fall off multiple times in one year. This indicates that your tooth may have been prepared with retention form that is insufficient.

To move forward, it would be a good idea to consult a dentist experienced in placing crowns that will stay on.

This article was brought to you by Gilbert CEREC Crown provider, Dr. Matthew Roper.

What should I do if my CEREC crown broke?

Two weeks ago, I had a CEREC crown done. I was recently eating, when I felt something come loose in my mouth. I came to find out this crown had broken in half. The dentist offered to fix the crown free of charge. While I was thankful for this, I wanted to know why this happened. I want to be sure this was just a fluke circumstance and not an error made by the dentist.

Sincerely,
Randi

Dear Randi,

While this is quite rare, there are some things that may have hinted that something was “off”, like tooth pain, jaw pain, or if the tooth was connecting first when you bit down.

Another possibility is the way the material handled stress, though it is unlikely that this is the case. However, if this were the case, it is possible there was some sort of defect in the material before use, though this, too, is unlikely.

Another thought is if you grind or clench your teeth, this may be the cause. Each tooth has a different threshold in terms of the amount of force it can withstand. This is why some restorations my break, while others do not. If this occurs during the day, practicing relaxation exercises can help. If it’s taking place at night, a night guard will prevent the grinding.

The majority of crowns can handle this to an extent, so you can’t rule out the material used or a mistake made by the dentist. It’s worth having him redo the procedure. It would be good to see what he thinks is the cause. Dentists have restorations fail from time to time. So long as this is not the norm, and he wants to fix the issue, it sounds like you’re in good hands.

This post is brought to you by Gilbert CEREC provider Dr. Matt Roper.

Rough crown

I had a cerec crown put in and on the follow up visit my dentist accidentally damaged it. he said that wouldn’t be a problem because he saved everything on the computer and could just make another one and gave me a temp crown. the problem is the new crown seems rough. i think i remember my first cerec crown being really smooth like glass. i was happy about that because it reminded me of my regualar tooth. do you think my dentist is pulling a fast one on me and not putting a new cerec crown in and just putting some other kind that isn’t as smooth?

Jeremy V. from El Dorado, AR

Jeremy,

No matter what type of crown your dentist puts in, it should be smooth and natural feeling. If it is rough, it is possible your dentist took off some of the glaze when he made his adjustments. Maybe he tried to repair the crown he damaged, in the process removing some of the glaze, instead of making a new CEREC crown.

If you have reason to doubt his ethics, I would get a second opinion about your crown, but don’t tell the second dentist who your dentist is or the dental history of it. Simply ask him what he thinks the crown is made of. This way the dentist won’t be tempted to tell you what he thinks you want to hear. Nor, will he know which dentist you went to and feel some loyalty to a peer with whom he is on friendly terms.

If you don’t doubt his ethics, then I would simply point out that the glaze was damaged somehow and have him re-polish it. That is a simple procedure.

This blog is brought to you by Gilbert dentist Dr. Matt Roper.